Breedcow Dynama - User contributions [en]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-06-22T00:09:50Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator. The information about the feed quality can be found either on the product label, from the feed provider, or by contacting a ruminant nutritionist or beef extension officer.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms. If a target end weight is known then enter the mid point weight between starting and ending weight.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varies from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator (Figure 4), a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
#The first step is to enter data into the first two yellow entry cells:
#:*Firstly, enter the total amount of weight the animal needs to gain on the prescribed feed, measured in kilograms. E.g. 40kg desired weight gain to meet a market.
#:*Secondly, the ramp up time for the feed is optional to use, it is for when the ration being fed requires gradual introduction over time before ramping up to the full ration intake to avoid problems like acidosis in the animals. Thi

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-04-28T22:25:32Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator. The information about the feed quality can be found either on the product label, from the feed provider, or by contacting a ruminant nutritionist or beef extension officer.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms. If a target end weight is known then enter the mid point weight between starting and ending weight.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator (Figure 4), a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
#The first step is to enter data into the first two yellow entry cells:
#:*Firstly, enter the total amount of weight the animal needs to gain on the prescribed feed, measured in kilograms. E.g. 40kg desired weight gain to meet a market.
#:*Secondly, the ramp up time for the feed is optional to use, it is for when the ration being fed requires gradual introduction over time before ramping up to the full ration intake to avoid problems like acidosis in the animals. This ramp up time is entered in days, where 0 means no ramp up required.
#The tool then calculates a number of outputs for mature and growing stock using the LWG results (Figure 3) from the LWG calculator and the data entered in step 1:
#:*Days taken to gain the desired weight gain if fed on full diet (i.e. when ramp up time = 0)
#:*Days taken to gain the desired weight gain including the ramp up time (i.e. when ramp up time = greater than 0)
#:*The effective LWG per day in kilograms adjusted for the extra time fed in ramp up time (i.e. if ramp up = 0 then effective LWG will be the same as in the LWG calculator, and if ramp up = >0 then the effective LWG will be lower then what is in the LWG Calculator.

[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided, or calculated information including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter (DM): component of the feed left after drying.
*Dry matter digestibility (DMD): the level of digestibility on a dry matter basis, expressed as a percentage.
*Metabolisable energy (ME): the part of dietary energy remaining after losses in faeces, urine and rumen gasses.
*Maintenance metabolisable energy requirement (MEm): the ME required for an animal to maintain current bodyweight.
*Megajoules (MJ): the units in which energy is measured.
*Dry matter intake (DMI): the amount of dry matter eaten by an animal, expressed as a percentage of bodyweight.

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:45:01Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 80:20 grain (80%) to roughage/grass (20%) after a ramp up time of 14 days to avoid acidosis.'''

In this example there are two different feeds, the grain ration and the roughage/grass portion.

There are two correct ways to approach this scenario.
*The first way, which will be used in this example, involves the user entering the information for each feed separately and save each scenario in the LWG calculator summary section, then use the Feed cost calculator to calculate the combined diet LWG and feed consumed.
*The second way is to enter the information of the combined diet as one scenario by using weighted averages of the information about each feed.

Begin the scenario by typing in the description box an identifiable title ''i.e. steers 480-580kg (Diet 80:20 grain and roughage) GRAIN portion''

#Start entering the data starting with the '''''Primary inputs''''', listed below.
#*Metabolisable energy (ME): The grain ration in this example has a ME of 11.32MJ/kg of dry matter. Enter 11.32 in the cell.
#*Animal live weight (W): The starting weight is 480kg and target weight is 580kg so enter the mid point of 530kg to reflect an average weight over the time.
#*Dry matter digestibility (DMD): The grain portion of the ration has a DMD of 89%
#*Animal age in years: In the example the animal is approximately 3 years old.
#The next step is the '''''Secondary inputs''''', listed below, most of these often do not need to be changed between scenarios but check to make sure.
#*Standard reference weight (SRW) or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#*K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#*Average walking distance to water, measured in kilometres (km)
#*S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#*GF: availability of green forage, measured in tonnes per hectare (t/ha)
#*M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#*SR: current grazing density, measured in animals per hectare
#*Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#*T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#*SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#*B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:43:26Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 80:20 grain (80%) to roughage/grass (20%) after a ramp up time of 14 days to avoid acidosis.'''

In this example there are two different feeds, the grain ration and the roughage/grass portion.

There are two correct ways to approach this scenario.
*The first way, which will be used in this example, involves the user entering the information for each feed separately and save each scenario in the LWG calculator summary section, then use the Feed cost calculator to calculate the combined diet LWG and feed consumed.
*The second way is to enter the information of the combined diet as one scenario by using weighted averages of the information about each feed.

Begin the scenario by typing in the description box an identifiable title ''i.e. steers 480-580kg (Diet 80:20 grain and roughage) GRAIN portion''

#Start entering the data starting with the '''''Primary inputs''''', steps 1 to 4 listed below.
#*Metabolisable energy (ME): The grain ration in this example has a ME of 11.32MJ/kg of dry matter. Enter 11.32 in the cell.
#*Animal live weight (W): The starting weight is 480kg and target weight is 580kg so enter the mid point of 530kg to reflect an average weight over the time.
#*Dry matter digestibility (DMD): The grain portion of the ration has a DMD of 89%
#*Animal age in years: In the example the animal is approximately 3 years old.
#The next step is the '''''Secondary inputs''''', steps 0 to 0 listed below, most of these often do not need to be changed between scenarios but check to make sure.
#*SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#*K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#*Average walking distance to water, measured in kilometres (km)
#*S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#*GF: availability of green forage, measured in tonnes per hectare (t/ha)
#*M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#*SR: current grazing density, measured in animals per hectare
#*Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#*T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#*SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#*B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:43:05Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 80:20 grain (80%) to roughage/grass (20%) after a ramp up time of 14 days to avoid acidosis.'''

In this example there are two different feeds, the grain ration and the roughage/grass portion.

There are two correct ways to approach this scenario.
*The first way, which will be used in this example, involves the user entering the information for each feed separately and save each scenario in the LWG calculator summary section, then use the Feed cost calculator to calculate the combined diet LWG and feed consumed.
*The second way is to enter the information of the combined diet as one scenario by using weighted averages of the information about each feed.

Begin the scenario by typing in the description box an identifiable title ''i.e. steers 480-580kg (Diet 80:20 grain and roughage) GRAIN portion''

#Start entering the data starting with the '''''Primary inputs''''', steps 1 to 4 listed below.
#*Metabolisable energy (ME): The grain ration in this example has a ME of 11.32MJ/kg of dry matter. Enter 11.32 in the cell.
#*Animal live weight (W): The starting weight is 480kg and target weight is 580kg so enter the mid point of 530kg to reflect an average weight over the time.
#*Dry matter digestibility (DMD): The grain portion of the ration has a DMD of 89%
#*Animal age in years: In the example the animal is approximately 3 years old.
#The next step is the '''''Secondary inputs''''', steps 0 to 0 listed below, most of these often do not need to be changed between scenarios but check to make sure.

#*SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#*K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#*Average walking distance to water, measured in kilometres (km)
#*S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#*GF: availability of green forage, measured in tonnes per hectare (t/ha)
#*M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#*SR: current grazing density, measured in animals per hectare
#*Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#*T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#*SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#*B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:42:07Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 80:20 grain (80%) to roughage/grass (20%) after a ramp up time of 14 days to avoid acidosis.'''

In this example there are two different feeds, the grain ration and the roughage/grass portion.

There are two correct ways to approach this scenario.
*The first way, which will be used in this example, involves the user entering the information for each feed separately and save each scenario in the LWG calculator summary section, then use the Feed cost calculator to calculate the combined diet LWG and feed consumed.
*The second way is to enter the information of the combined diet as one scenario by using weighted averages of the information about each feed.

Begin the scenario by typing in the description box an identifiable title ''i.e. steers 480-580kg (Diet 80:20 grain and roughage) GRAIN portion''

#Start entering the data starting with the '''''Primary inputs''''', steps 1 to 4 listed below.

#*Metabolisable energy (ME): The grain ration in this example has a ME of 11.32MJ/kg of dry matter. Enter 11.32 in the cell.
#*Animal live weight (W): The starting weight is 480kg and target weight is 580kg so enter the mid point of 530kg to reflect an average weight over the time.
#*Dry matter digestibility (DMD): The grain portion of the ration has a DMD of 89%
#*Animal age in years: In the example the animal is approximately 3 years old.

#The next step is the '''''Secondary inputs''''', steps 0 to 0 listed below, most of these often do not need to be changed between scenarios but check to make sure.

#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:39:51Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 80:20 grain (80%) to roughage/grass (20%) after a ramp up time of 14 days to avoid acidosis.'''

In this example there are two different feeds, the grain ration and the roughage/grass portion.

There are two correct ways to approach this scenario.
*The first way, which will be used in this example, involves the user entering the information for each feed separately and save each scenario in the LWG calculator summary section, then use the Feed cost calculator to calculate the combined diet LWG and feed consumed.
*The second way is to enter the information of the combined diet as one scenario by using weighted averages of the information about each feed.

Begin the scenario by typing in the description box an identifiable title ''i.e. steers 480-580kg (Diet 80:20 grain and roughage) GRAIN portion''

Start entering the data starting with the '''''Primary inputs''''', steps 1 to 4 listed below.

#Metabolisable energy (ME): The grain ration in this example has a ME of 11.32MJ/kg of dry matter. Enter 11.32 in the cell.
#Animal live weight (W): The starting weight is 480kg and target weight is 580kg so enter the mid point of 530kg to reflect an average weight over the time.
#Dry matter digestibility (DMD): The grain portion of the ration has a DMD of 89%
#Animal age in years: In the example the animal is approximately 3 years old.
#:The next step is the '''''Secondary inputs''''', steps 0 to 0 listed below, most of these often do not need to be changed between scenarios but check to make sure.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:38:27Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 80:20 grain (80%) to roughage/grass (20%) after a ramp up time of 14 days to avoid acidosis.'''

In this example there are two different feeds, the grain ration and the roughage/grass portion.

There are two correct ways to approach this scenario.
*The first way, which will be used in this example, involves the user entering the information for each feed separately and save each scenario in the LWG calculator summary section, then use the Feed cost calculator to calculate the combined diet LWG and feed consumed.
*The second way is to enter the information of the combined diet as one scenario by using weighted averages of the information about each feed.

Begin the scenario by typing in the description box an identifiable title ''i.e. steers 480-580kg (Diet 80:20 grain and roughage) GRAIN portion''

Start entering the data starting with the '''''Primary inputs''''', steps 1 to 4 listed below.

#Metabolisable energy (ME): The grain ration in this example has a ME of 11.32MJ/kg of dry matter. Enter 11.32 in the cell.
#Animal live weight (W): The starting weight is 480kg and target weight is 580kg so enter the mid point of 530kg to reflect an average weight over the time.
#Dry matter digestibility (DMD): The grain portion of the ration has a DMD of 89%
#Animal age in years: In the example the animal is approximately 3 years old.
The next step is the '''''Secondary inputs''''', steps 0 to 0 listed below, most of these often do not need to be changed between scenarios but check to make sure.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:37:53Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 80:20 grain (80%) to roughage/grass (20%) after a ramp up time of 14 days to avoid acidosis.'''

In this example there are two different feeds, the grain ration and the roughage/grass portion.

There are two correct ways to approach this scenario.
*The first way, which will be used in this example, involves the user entering the information for each feed separately and save each scenario in the LWG calculator summary section, then use the Feed cost calculator to calculate the combined diet LWG and feed consumed.
*The second way is to enter the information of the combined diet as one scenario by using weighted averages of the information about each feed.

Begin the scenario by typing in the description box an identifiable title ''i.e. steers 480-580kg (Diet 80:20 grain and roughage) GRAIN portion''

Start entering the data starting with the '''''Primary inputs''''', steps 1 to 4 listed below.

#Metabolisable energy (ME): The grain ration in this example has a ME of 11.32MJ/kg of dry matter. Enter 11.32 in the cell.
#Animal live weight (W): The starting weight is 480kg and target weight is 580kg so enter the mid point of 530kg to reflect an average weight over the time.
#Dry matter digestibility (DMD): The grain portion of the ration has a DMD of 89%
#Animal age in years: In the example the animal is approximately 3 years old.

The next step is the '''''Secondary inputs''''', steps 0 to 0 listed below, most of these often do not need to be changed between scenarios but check to make sure.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:28:25Z

Daisy:

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:24:31Z

Daisy:

Example one: Feed-on steers 480 to 580kg

2021-04-13T04:22:57Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-04-13T04:11:32Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator. The information about the feed quality can be found either on the product label, from the feed provider, or by contacting a ruminant nutritionist or beef extension officer.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms. If a target end weight is known then enter the mid point weight between stating and ending weight.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator (Figure 4), a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
#The first step is to enter data into the first two yellow entry cells:
#:*Firstly, enter the total amount of weight the animal needs to gain on the prescribed feed, measured in kilograms. E.g. 40kg desired weight gain to meet a market.
#:*Secondly, the ramp up time for the feed is optional to use, it is for when the ration being fed requires gradual introduction over time before ramping up to the full ration intake to avoid problems like acidosis in the animals. This ramp up time is entered in days, where 0 means no ramp up required.
#The tool then calculates a number of outputs for mature and growing stock using the LWG results (Figure 3) from the LWG calculator and the data entered in step 1:
#:*Days taken to gain the desired weight gain if fed on full diet (i.e. when ramp up time = 0)
#:*Days taken to gain the desired weight gain including the ramp up time (i.e. when ramp up time = greater than 0)
#:*The effective LWG per day in kilograms adjusted for the extra time fed in ramp up time (i.e. if ramp up = 0 then effective LWG will be the same as in the LWG calculator, and if ramp up = >0 then the effective LWG will be lower then what is in the LWG Calculator.

[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided, or calculated information including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter (DM): component of the feed left after drying.
*Dry matter digestibility (DMD): the level of digestibility on a dry matter basis, expressed as a percentage.
*Metabolisable energy (ME): the part of dietary energy remaining after losses in faeces, urine and rumen gasses.
*Maintenance metabolisable energy requirement (MEm): the ME required for an animal to maintain current bodyweight.
*Megajoules (MJ): the units in which energy is measured.
*Dry matter intake (DMI): the amount of dry matter eaten by an animal, expressed as a percentage of bodyweight.

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-13T03:58:51Z

Daisy:

Example one: Feed-on steers 480 to 580kg

2021-04-12T05:14:39Z

Daisy:

Example one: Feed-on steers 480 to 580kg

2021-04-12T04:48:39Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: The yellow cells are for inputs and can be adjusted, while the rest are interim functions or calculated outputs.''

----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 90:10 grain to roughage after a ramp up time of 14 days.'''

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-12T04:46:31Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: The yellow cells are for inputs and can be adjusted, while the rest are interim functions or calculated outputs.''

The [[LWG Calculator]]

----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 90:10 grain to roughage after a ramp up time of 14 days.'''

----

Follow these links for more examples of using this calculator:

[[Introduction to the LWG Calculator: the functionality, assumptions & definitions]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Example one: Feed-on steers 480 to 580kg

2021-04-12T04:38:43Z

Daisy:

Copy the example scenario (''Example one: Feed-one steers 480 to 580kg'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: The yellow cells are for inputs and can be adjusted, while the rest are interim functions or calculated outputs.''

The [[LWG Calculator]]

----
'''Example one describes taking feed-on steers through from 480 to 580kg live weight on a grain ration. The diet is fed on a ratio of 90:10 grain to roughage after a ramp up time of 14 days.'''

Example one: Purchasing PTIC cows for trading

2021-04-12T04:33:58Z

Daisy:

Copy the example scenario (''Purchase of PTIC cows for trading'') from the examples list and open the scenario, this will illustrate how the program may be used in the following example.

''Note: The yellow cells are for inputs and can be adjusted, while the rest are calculated outputs.''

The [[Cowtrade]] program allows for the input of ''Standard weight of one Adult Equivalent'' and ''Extra Adult Equivalents for cow weaning a calf'', the default values being 455kg and 0.35 respectively, see figure 1. One [[Adult_equivalent|Adult Equivalent]] is a non-lactating animal of average 455kg liveweight carried for a year. It is generally unnecessary to change these values unless the user is using a different Adult Equivalent convention for comparing grazing pressure and they wish to tailor it to their requirements. If the analysis period is less than the duration of pregnancy plus five months, a proportional value for the adult equivalent rating of the calf is calculated.

[[file:Cowtrade2.JPG|center|frame|Figure 1 - Cowtrade AE's]]

----
'''Example one describes pregnancy tested in calf (PTIC) cows being purchased early in July and sold in June of the following year. The calves have an average birth date of November and are to be sold as weaners through the local yards. Cows are to be sold to the abattoirs.'''

The steps below take the user through the data entry displayed in Figure 2.

#Begin by entering the ''Start date for the analysis'' (usually the date the stock are purchased), ''Expected calving date'', expected future ''Sale date for adults'', ''Sale date for progeny'', ''Weight of breeders at start and sale'', ''Weight of progeny at 5 months and sale''. Sale can be either a normal sale, or a transfer at valuation of weaner or breeder back into the herd. These dates and weights are used mainly to calculate adult equivalents.
#When entering the ''Starting value/head of group'' for purchased cattle this should be their landed value. For a destocking analysis assessing breeders already in the herd, the net value that would be achieved if that animal were to be sold should be used, there are calculators in the Cowtrade program which will help the user calculate these values, they are located below the scenario summaries in the web page.
#''Sale values'' may be entered as per head net values, or may be calculated from weights, price per kilogram and selling and transport costs using the calculators at the bottom of the web page. Explanation and examples for the use of the calculators can be found in the [[Cowtrade_calculators|Cowtrade calculators page]].
#Enter the ''Interest rate for Gross Margin after interest'', this should be viewed as the opportunity cost, especially if using business funds rather than borrowed funds.
#Enter the appropriate ''Weaning rate from breeders'' and ''Death rate'' on stock classes.
#Enter expected ''Husbandry cost'' for the stock classes based on the duration of the analysis.

[[file:Cowtrade3.JPG|frame|center|Figure 2 - Cowtrade data entry]]

----

The results of the analysis, as displayed in Figure 3, can be found to the right of the yellow input cells and summarised in a column below the inputs section on the web page. The results can be saved by clicking the ''Save'' button at the bottom of the summary column and renamed by typing in the yellow box beside description of the group.

The results calculated include adult equivalent ratings for breeder and progeny over the time held, and gross margin (per unit, per adult equivalent, and as a percent of livestock and expenses capital). The results of the example indicate the purchase of PTIC cows has a positive gross margin (gross margin after interest is $156.21/AE/year) and may be profitable depending on what the alternative uses of the feed resource may be. The results of the analysis are much more useful and meaningful once compared to alternative uses of the feed resource, modelled in Bullocks or a different scenario in Cowtrade. When doing this you would pick the most profitable scenario that is feasible to do with the feed available.

[[file:Cowtrade4.JPG|center|frame|Figure 3 - Cowtrade results output]]

----

The results of the analysis can be further tested for their sensitivity to sale price increments in the section at the very bottom of the web page, below the calculators section. See Figure 4 for sensitivity tables. In the table it can be seen that small variation in the sale price of either breeder or progeny can significantly impact returns from the venture.

[[file:Cowtrade5.JPG|center|frame|Figure 4 - Price sensitivity tables]]

----

Follow these links for more examples of using Cowtrade:

[[Example two: Assessing a drought feeding option]]

[[Example three: Wet season trading cows and calves]]

Example one: Feed-on steers 480 to 580kg

2021-04-12T04:11:27Z

Daisy: Created page with "Step 1"

Step 1

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-25T05:27:00Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator (Figure 4), a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
#The first step is to enter data into the first two yellow entry cells:
#:*Firstly, enter the total amount of weight the animal needs to gain on the prescribed feed, measured in kilograms. E.g. 40kg desired weight gain to meet a market.
#:*Secondly, the ramp up time for the feed is optional to use, it is for when the ration being fed requires gradual introduction over time before ramping up to the full ration intake to avoid problems like acidosis in the animals. This ramp up time is entered in days, where 0 means no ramp up required.
#The tool then calculates a number of outputs for mature and growing stock using the LWG results (Figure 3) from the LWG calculator and the data entered in step 1:
#:*Days taken to gain the desired weight gain if fed on full diet (i.e. when ramp up time = 0)
#:*Days taken to gain the desired weight gain including the ramp up time (i.e. when ramp up time = greater than 0)
#:*The effective LWG per day in kilograms adjusted for the extra time fed in ramp up time (i.e. if ramp up = 0 then effective LWG will be the same as in the LWG calculator, and if ramp up = >0 then the effective LWG will be lower then what is in the LWG Calculator.

[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided, or calculated information including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter (DM): component of the feed left after drying.
*Dry matter digestibility (DMD): the level of digestibility on a dry matter basis, expressed as a percentage.
*Metabolisable energy (ME): the part of dietary energy remaining after losses in faeces, urine and rumen gasses.
*Maintenance metabolisable energy requirement (MEm): the ME required for an animal to maintain current bodyweight.
*Megajoules (MJ): the units in which energy is measured.
*Dry matter intake (DMI): the amount of dry matter eaten by an animal, expressed as a percentage of bodyweight.

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-25T02:16:02Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator (Figure 4), a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
#The first step is to enter data into the first two yellow entry cells:
#:*Firstly, enter the total amount of weight the animal needs to gain on the prescribed feed, measured in kilograms. E.g. 40kg desired weight gain to meet a market.
#:*Secondly, the ramp up time for the feed is optional to use, it is for when the ration being fed requires gradual introduction over time before ramping up to the full ration intake to avoid problems like acidosis in the animals. This ramp up time is entered in days, where 0 means no ramp up required.
#The tool then calculates a number of outputs for mature and growing stock using the LWG results (Figure 3) from the LWG calculator and the data entered in step 1:
#:*Days taken to gain the desired weight gain if fed on full diet (i.e. when ramp up time = 0)
#:*Days taken to gain the desired weight gain including the ramp up time (i.e. when ramp up time = greater than 0)
#:*The effective LWG per day in kilograms adjusted for the extra time fed in ramp up time (i.e. if ramp up = 0 then effective LWG will be the same as in the LWG calculator, and if ramp up = >0 then the effective LWG will be lower then what is in the LWG Calculator.

[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter (DM): component of the feed left after drying.
*Dry matter digestibility (DMD): the level of digestibility on a dry matter basis, expressed as a percentage.
*Metabolisable energy (ME): the part of dietary energy remaining after losses in faeces, urine and rumen gasses.
*Maintenance metabolisable energy requirement (MEm): the ME required for an animal to maintain current bodyweight.
*Megajoules (MJ): the units in which energy is measured.
*Dry matter intake (DMI): the amount of dry matter eaten by an animal, expressed as a percentage of bodyweight.

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-25T02:06:52Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator (Figure 4), a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
#The first step is to enter data into the first two yellow entry cells
#:*Firstly, enter the total amount of weight the animal needs to gain on the prescribed feed, measured in kilograms. E.g. 40kg desired weight gain to meet a market.
#:*Secondly, the ramp up time for the feed is optional to use, it is for when the ration being fed requires gradual introduction over time before ramping up to the full ration intake to avoid problems like acidosis in the animals. This ramp up time is entered in days, where 0 means no ramp up required.
#The calculator then calculates

[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter (DM): component of the feed left after drying.
*Dry matter digestibility (DMD): the level of digestibility on a dry matter basis, expressed as a percentage.
*Metabolisable energy (ME): the part of dietary energy remaining after losses in faeces, urine and rumen gasses.
*Maintenance metabolisable energy requirement (MEm): the ME required for an animal to maintain current bodyweight.
*Megajoules (MJ): the units in which energy is measured.
*Dry matter intake (DMI): the amount of dry matter eaten by an animal, expressed as a percentage of bodyweight.

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-25T02:05:11Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator (Figure 4), a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
#The first step is to enter data into the first two yellow entry cells
#:Firstly, enter the total amount of weight the animal needs to gain on the prescribed feed, measured in kilograms. E.g. 40kg desired weight gain to meet a market.
#:Secondly, the ramp up time for the feed is optional to use, it is for when the ration being fed requires gradual introduction over time before ramping up to the full ration intake to avoid problems like acidosis in the animals. This ramp up time is entered in days, where 0 means no ramp up required.
#The calculator then calculates

[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter (DM): component of the feed left after drying.
*Dry matter digestibility (DMD): the level of digestibility on a dry matter basis, expressed as a percentage.
*Metabolisable energy (ME): the part of dietary energy remaining after losses in faeces, urine and rumen gasses.
*Maintenance metabolisable energy requirement (MEm): the ME required for an animal to maintain current bodyweight.
*Megajoules (MJ): the units in which energy is measured.
*Dry matter intake (DMI): the amount of dry matter eaten by an animal, expressed as a percentage of bodyweight.

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-24T22:27:41Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator, a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter (DM): component of the feed left after drying.
*Dry matter digestibility (DMD): the level of digestibility on a dry matter basis, expressed as a percentage.
*Metabolisable energy (ME): the part of dietary energy remaining after losses in faeces, urine and rumen gasses.
*Maintenance metabolisable energy requirement (MEm): the ME required for an animal to maintain current bodyweight.
*Megajoules (MJ): the units in which energy is measured.
*Dry matter intake (DMI): the amount of dry matter eaten by an animal, expressed as a percentage of bodyweight.

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-24T22:09:11Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).
#LWG mature: Mature stock live weight gain per day in kilograms, LWG mature = (MEI - MEm) / ME requirement for 1kg of gain
#LWG growing: Growing stock live weight gain per day in kilograms, LWG growing = ER / (0.92 x EBG)

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator, a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter digestibility (DMD):
*Metabolisable energy (ME):
*Maintenance metabolisable energy requirement (MEm):
*Dry matter intake as a percent of body weight (DMI):

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-24T22:03:09Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator, a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''
[[file:Growing_time_calc.PNG|center|frame|Figure 4 - Growing time calculator]]
----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter digestibility (DMD):
*Metabolisable energy (ME):
*Maintenance metabolisable energy requirement (MEm):
*Dry matter intake as a percent of body weight (DMI):

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

File:Growing time calc.PNG

2021-03-24T22:01:57Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-24T21:59:11Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator, a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''

----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range, approximately 3.
*Dry matter digestibility (DMD):
*Metabolisable energy (ME):
*Maintenance metabolisable energy requirement (MEm):
*Dry matter intake as a percent of body weight (DMI):

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-24T02:38:50Z

Daisy:

==Summary==
This page will explain what the tools are able to do, how to use them, the information required and definitions of of technical terms. The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
'''This section describes the inputs and outputs of the LWG Calculator, a tool which estimates the potential live weight gain an animal will experience given user provided nutritional and animal information.'''

The calculator begins with a section called '''''Primary Inputs''''' (Figure 1), it requires the user to fill out the first four yellow input cells. These are the most important data entry cells and will be needed for any scenario in the LWG calculator.
#ME: metabolisable energy of the feed measured in megajoules per kilogram (MJ/kg) of dry matter as fed.
#W: the current animal live weight, measured in kilograms.
#DMD: the dry matter digestibility of the feed as fed, entered as a percentage.
#Animal age measured in years, e.g. 18mths = 1.5, with a maximum value of 6.0 when exp(-0.03A)=0.84

The following section, '''''Secondary Inputs''''' (Figure 1), contains several yellow data entry cells, most of which do not need to be changed from the default values. If the user wishes to adjust theses inputs this section will explain the variables and how to do this.
#SRW: standard reference weight or the expected mature weight of the animal where skeletal development is complete and the animal is in body condition score 3, measured in kilograms. The default value here is 660kg, this is the recommended SRW for a Brahman or Brahman cross castrated male, the SRW for the same female animal is 550kg, and for the entire male is 770kg.
#K: a constant value representing the cattle breed, enter 1.2 for ''B. indicus'', 1.4 for ''B. taurus'' breeds, or an intermediate value 1.2-1.4 for cross breeds.
#Average walking distance to water, measured in kilometres (km)
#S: enter a constant value of 1.0 for females and castrates (steers, heifers, cows, bullocks), and enter 1.15 for entire males (bulls)
#GF: availability of green forage, measured in tonnes per hectare (t/ha)
#M: the fraction of dietary intake provided by milk (M = 1 + 0.23 x DE from milk, minimum value of M = 1), enter 1 for a weaned animal. This tool is not designed to be used for unweaned stock.
#SR: current grazing density, measured in animals per hectare
#Ecold: additional energy expenditure from cold stress, measured in megajoules (MJ). This occurs when the ambient temperature is below the animal’s lower critical temperature, e.g. at maintenance nutrition, a store animal's lower critical temperature in dry still air is -16 degrees Celsius. In northern Australian grazing systems the Ecold value can be set to 0.
#T: terrain constant, enter from 1.0 to 2.0 as terrain varied from level to steep.
#SD: threshold for grazing density, enter the value 5 for cattle (animals/hectare)
#B: the approximate birth weight of the animal, measured in kilograms. Cattle have a birthweight of approximately 35kg.

[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

Following the primary and secondary inputs section in the tool there is a '''''Functions''''' section (Figure 2). This section is a locked display of the interim calculations that go into the resulting mature and growing stock estimated daily live weight gains. It is not necessary for the user to go through or understand all this information, however, some of the variables are useful to know, e.g. dry matter intake per day (kg) is useful to know for feed budgeting.
#M/D: the megajoules of ME per kilogram of feed dry matter, M/D = 0.172 x (DMD x 100) - 1.707
#km: net efficiency of ME used for maintenance, km = 0.02 x M/D + 0.5
#H: horizontal equivalent of distance walked in kilometres, H = T x ((MIN(1,SR/SD) / (0.057 x GF + 0.16) + walking distance to water))
#MEgraze: additional energy expenditure from grazing, MEgraze = ((0.00258 x DMI x(0.9 - DMD) + 0.0026 x H) x W) / km
#Kg: the term describes the efficiency of use of ME for growth, Kg = 0.043 M/D
#L: the level of feeding, L = MEI / MEm
#R: adjustment rate for gain or loss, R = L - 2
#ER: energy retention, ER = kg x (MEI - MEm)
#Z: the proportion of mature size where 1.0 is maturity, Z = W / SRW
#N: the upper limit to normal weight, N = SRW -(SRW - B) x EXP(-0.35 x T x SRW^-0.27)
#RC: the relative condition of the animal, RC = W / N
#CF: the condition factor for non-lactating animals, CF = IF(RC>1,RC x (1.5 - RC) / 0.5,1)
#I: potential animal feed intake in kilograms of dry matter per day, I = 0.025 x SRW x Z x (1.7 - Z) x CF
#EBG: empty body weight gain, EBG = (6.7 + 1 x R)+(20.3 - 1 x R)/(1 + EXP(-6 x (Z - 0.4)))
#T: animal age in months, T = animal age x 12
#DMI: dry matter intake per day as a percentage of live weight, the calculator uses the approximate DMD of the feed and weight of the animal to look up the most likely DMI from animal intake tables published in The Nutrition EDGE Workshop Notes by Meat and Livestock Australia.
#EVG mature: energy content of EBG, EVG mature = 0.92 x (9.4 + 13.8 x W / SRW)
#ME requirement for 1kg of live weight gain: ME 1kg LWG = EVG mature / kg
#DMI per day on feed: the dry matter intake per day on the feed in kilograms, DMI kg/day = W x DMI, if this value is greater than the potential intake (I) then it equals I
#MEI: total ME intake per day on the described feed, MEI = ME x DMI per day on feed
#MEm: ME requirement for maintenance, MEm = K x S x M x ((0.26 x W^0.75) x EXP(-0.03 x Age)) / km + 0.09 x MEI + MEgraze + Ecold

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

The final section of the LWG calculator is the '''''LWG Calculator Results''''' (Figure 3).

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]
----
===Growing time calculator===
'''This section outlines how to use the Growing Time Calculator, a tool that uses the LWG information from the calculator and user inputted desired weight gain and ration ramp up time to calculate days to gain weight.'''

----
===Feed cost calculator===
'''This section outlines how to use the Feed Cost Calculator, a standalone tool using user provided information or calculated from the other tools including, feed cost, LWG, animal intake, and days fed to calculate cost and quantity of feed consumed for a time on the diet.'''

==Definitions==
*Standard reference weight (SRW): the live weight of an animal when skeletal development is complete and the condition score is in the middle of the range.
*Dry matter digestibility (DMD):
----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-24T01:59:08Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-24T00:02:13Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:48:51Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:47:42Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:42:36Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:38:57Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:32:47Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:26:25Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:23:53Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T23:10:08Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T22:26:30Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T21:50:57Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T21:44:24Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T00:31:33Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T00:17:52Z

Daisy: /* Functionality */

==Summary==
The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality of the tools==

===LWG Calculator===
[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]

===Growing time calculator===

===Feed cost calculator===

==Definitions==

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T00:17:13Z

Daisy: /* LWG Calculator */

==Summary==
The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality==

===LWG Calculator===
[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

[[file:LWG_calc_functions.PNG|center|frame|Figure 2 - LWG Calculator functions]]

[[file:LWG_calc_results.PNG|center|frame|Figure 3 - LWG Calculator results]]

===Growing time calculator===

===Feed cost calculator===

==Definitions==

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

File:LWG calc results.PNG

2021-03-23T00:15:51Z

Daisy:

File:LWG calc functions.PNG

2021-03-23T00:15:32Z

Daisy:

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T00:04:16Z

Daisy:

==Summary==
The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality==

===LWG Calculator===
[[file:LWG_calc_inputs.PNG|center|frame|Figure 1 - LWG Calculator input cells]]

===Growing time calculator===

===Feed cost calculator===

==Definitions==

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]

Introduction to the LWG Calculator: the functionality, assumptions & definitions

2021-03-23T00:02:45Z

Daisy:

==Summary==
The tool is broken down into three parts:
#'''[[LWG Calculator]]''', This is the main tool which results in an estimated live weight gain for an animal on a certain type of feed.
#'''Growing time calculator''', This tool calculates the time it takes for an animal to put on an entered amount of weight using the results from the LWG Calculator.
#'''Feed cost calculator''', This tool can be used alone or using results from the other two tools to calculate feed quantity consumed and the cost.

''Note: Data can be entered or changed in the cells with a yellow background, while the results are displayed in the locked blue cells.''
==Functionality==

===LWG Calculator===
[[file:LWG_calc_inputs.JPG|center|frame|Figure 1 - LWG Calculator input cells]]

===Growing time calculator===

===Feed cost calculator===

==Definitions==

----

Follow these links for more examples of using this calculator:

[[Example one: Feed-on steers 480 to 580kg]]

[[Example two: Top up steers for the boat 260 to 330kg]]

[[Example three: Production feeding heifers 250 to 320kg]]