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Ruminant Livestock
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Ruminant Livestock

Using the Livestock Analysis Model

LAM TOC | LAM Introduction | Using the LAM | LAM Tutorial

System Requirements
Download the .zip File
Open the File to Start
Setting Production Targets
Production Characteristics
Characteristics for Estimating Methane Emissions Factors
Results
References


System Requirements

LAM was developed using Quattro Pro 5.0 for Windows and Excel 5.0 for Windows. To run LAM, MS Excel 5.0 or later is required.


Download the .zip File

The file livestock.zip should extract to LAM_101.XLS.


Open the File to Start

To use LAM, start Excel and open the LAM file. The model has been set to only allow entry in those cells in which the user can provide input.


Setting Production Targets

Exhibit 1 displays the screen for setting production targets. First, set the overall production targets for milk, meat, and draft power (measured as the number of head of draft animals). Then, spread the production targets into the various possible sectors using percentages (i.e., 0.50 would be 50%). You may enter a brief name for each sector. The following sectors may be used:

  • Milk Sectors: Four separate milk sectors may be defined, each with its own target and characteristics. For example, separate sectors may be defined for: peri-urban cows; rural cows; peri-urban buffalo; and rural buffalo.
  • Draft Sectors: Two separate draft sectors may be defined, each with its own target and characteristics. For example, separate sectors may be defined for: bullocks and buffalo.
  • Meat Sector: A single meat producing sector may be defined.

The overall targets are initially spread among the relevant sectors. For example, the milk target is spread among the milk sectors. However, all sectors can contribute to the production of all three products, depending on the production characteristics defined for each.

Exhibit 1: Setting Targets

In this example, milk and meat production targets are set, and the draft target is zero. The milk target is allocated to a single sector: Milk_1, with the label entered by the user as Urban. The meat target is allocated to the single meat sector. Because we have set the total draft production target to zero, it is not necessary to change any draft variables in the model. For example, the screen below shows draft production as split between two sectors, but each sector is producing 50% of zero. LAM will calculate a herd size and methane emissions of zero for the draft sector.

Exhibit 1: Setting Targets

Set Production Targets by Livestock Sector and Product

Product

Target

Milk Production (1000 tons/yr)

68,000.0

Draft Production (1000 Head)

0.0

Meat Production (1000 tons/yr)

9,000.0

Distribution of Production Targets by Sector

(Each Row Must Equal 100%)

Milk_1

Milk_2

Milk_3

Milk_4

Draft_1

Draft_2

Meat

Total

Sector Label (Optional) ==>

Urban

Rural

Blank

Blank

Temp

Tropic

All

Milk Production (1000 tons)

100%

0%

0%

0%

NA

NA

NA

100%

Draft Production (1000 Head)

NA

NA

NA

NA

50%

50%

NA

100%

Meat Production (1000 tons)

NA

NA

NA

NA

NA

NA

100%

100%

 


Production Characteristics

Exhibit 2 displays the screen for entering the production characteristics of each livestock sector. These characteristics are divided into the following categories:

  • Cows: Milk Production: This section is used to define the milk production characteristics. The percent of milk that is produced for target is the milk used to meet the milk production target for human consumption. In this example, only cows in the four milk sectors are listed as producing milk for humans to meet the target. In fact, all sectors can produce milk for humans.
  • Bulls: Ratio to Cows: This section lists the number of bulls per cow for the milk and meat sectors. This ratio is not needed for the draft sector, which is driven (in part) by the need to produce bulls for draft power.
  • Draft Power Definitions: This section defines the animals that can be used as draft power. In this example, 95% of the adult males are usable as draft and 50% of the non-bred adult females are usable as draft in the draft sectors only. "Wet" (lactating) bred females and "dry" (non-lactating) bred females may also be considered for draft use, but are set to zero in this example. Young animals (non-adults) are not counted as draft animals. Although this example only defines animals in the draft herd as providing draft power, the relevant animals in all sectors can be defined to provide draft power.

Exhibit 2: Production Characteristics

Milk_1

Milk_2

Milk_3

Milk_4

Draft_1

Draft_2

Meat

Urban

Rural

Blank

Blank

Temp

Tropic

All

Cows: Milk Production

Milk per lactation (tons)

6.80

6.80

6.80

6.80

0.90

0.90

1.74

Length of lactation (days)

305

305

305

305

200

200

200

Intercalving interval (days)

365

365

365

365

600

600

365

Percent of Cows that are Bred

100.0%

100.0%

100.0%

100.0%

75.0%

50.0%

90.0%

Percent of milk produced for target

100.0%

100.0%

100.0%

100.0%

0.0%

0.0%

0.0%

Bulls: Ratio to Cows

Bulls per cow

0.02

0.02

0.02

0.02

N/A

N/A

0.07

Draft Power Definitions

Pct adult males usable as draft

0%

0%

0%

0%

95%

95%

0%

Pct non-bred females usable as daft

0%

0%

0%

0%

50%

50%

0%

Pct "wet" females usable as daft

0%

0%

0%

0%

0%

0%

0%

Pct "dry" females usable as daft

0%

0%

0%

0%

0%

0%

0%

Meat Production Characteristics

Adult Male carcass wt (1000 kg)

0.300

0.300

0.300

0.300

0.180

0.180

0.300

Adult Female carcass wt (1000 kg)

0.250

0.250

0.250

0.250

0.150

0.150

0.200

Slaughter male carcass weight (1000 kg)

NA

NA

NA

NA

NA

NA

0.300

Slaughter female carcass weight (1000kg)

NA

NA

NA

NA

NA

NA

0.250

Transfer Young to Meat Sector? (1=Yes)

1

1

1

1

1

1

NA

Maximum Years in the Herd: Adults, Replacements, Young

Yrs in herd -- adult males (Max = 10)

8

8

8

8

10

10

8

Yrs in herd -- adult females (Max = 10)

5

5

5

5

10

10

8

Yrs in herd -- repl males (Max = 4)

1

1

1

1

4

4

1

Yrs in herd -- repl females (Max = 4)

1

1

1

1

4

4

1

Yrs in herd -- young males (Max = 4)

1

1

1

1

1

1

1

Yrs in herd -- young females (Max = 4)

1

1

1

1

1

1

1

Yrs to slaughter for slaughterstk (Max = 4)

NA

NA

NA

NA

NA

NA

0.4

Annual Mortality Rates

Annual death rate -- adult males

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

Annual death rate -- adult females

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

Annual death rate -- repl males

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

Annual death rate -- repl females

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

2.0%

Annual death rate -- young males

5.0%

5.0%

5.0%

5.0%

5.0%

5.0%

5.0%

Annual death rate -- young females

5.0%

5.0%

5.0%

5.0%

5.0%

5.0%

5.0%

Adult Male Cull Rate

2.0%

2.0%

2.0%

2.0%

0.0%

0.0%

10.0%

Adult Female Cull Rate

30.0%

35.0%

35.0%

35.0%

0.0%

0.0%

10.0%

Annual death rate -- slaughter stock

NA

NA

NA

NA

NA

NA

1.0%

  • Meat Production Characteristics: This section lists the carcass weights of the relevant animal types at slaughter. Adult males and females may be slaughtered in all sectors, and young animals grown specifically for meat production may be slaughtered in the meat sector. The adult animals are counted toward the meat target when they are culled and when they reach their maximum age. Animals lost due to other causes of death are not counted toward the meat target.

    In addition to the carcass weight, this section is used to indicate if "excess" young from a given sector are "transferred" to the meat sector for use in meeting the meat production targets. For example, it is often the case that the dairy sector produces more male calves than are needed in the dairy sector. These "excess calves" may be transferred to the meat sector and grown for slaughter. Transferring these excess young to the meat industry is indicated by a putting a one for this input. Putting a zero for this input causes the number of excess calves to be estimated in the dairy sector, but no additional computations are made for them. These calves, for example, may be exported or may be used to meet a deficiency in calves in another sector, such as the draft sector.
  • Maximum Years in the Herd: Adults, Replacements, and Young: This section defines the ages of the three animal types. By grouping the animals by level of development, the model can better represent animal populations in different areas of the world, where animals may mature at different rates. The LAM user can define the age categories by entering the "years in herd" for each. Generally, "young" animals may not be fully weaned and often experience rapid growth, "replacements" are weaned animals that are not fully mature and do not produce much draft or milk, and "adults" are fully mature animals. In this example, the animals grow relatively quickly, so that they are considered as "young" for one year and "replacement" for one year. After they are replacements, they are considered adults. The number of years it takes to grow to slaughter weight (following being young) is also listed. In this example, the meat animals are slaughtered at 1.4 years of age (1.0 years as young, and 0.4 years being grown for slaughter). The LAM user will be able to specify the methane emission characteristics for each of the age groups on the methane characteristics sheet.
  • Annual Mortality Rates: The annual mortality rates are used to simulate the loss of animals due to reasons other than for slaughter. Annual death rates are given for each animal type. These rates are considered when simulating the size of the population needed to meet the production targets. Additionally, cull rates for male and female adults are listed. The culled animals contribute to the meat targets, while the loss due to death from other causes does not.

 


Characteristics for Estimating Methane Emissions Factors

Exhibit 3 presents the data required to estimate methane emissions. Most of the information needed to estimate emissions is derived from the production characteristics, such as: milk production; percent bred; and definition as a draft animal. Several key inputs must be provided for each animal type in each sector. The following is required:

  • Weight: The average annual weight for the animal type is needed. This weight is a key input for estimating emissions. It is the principal driving factor for estimating feed intake, and is also used to estimate weight gain. Care must be taken to ensure that the weights used in this input table are consistent with the carcass weights used in the Production Characteristics input table.
  • Feeding Situation: The feeding situations are defined in LAM and the IPCC/OECD Emissions Inventory Guidelines (1994). In this example, the dairy animals are all stall fed. Other possible values are pasture/range fed and grazing over very large areas. These values are entered into LAM using a number code, which is shown in Exhibit 4.
  • Feed Digestibility. The feed digestibility also has an important impact on the methane emissions estimate. Typical values range from 50 percent for poor quality rangelands to over 75 percent for grain-fed slaughter animals. Typical values will be in the range of 60 to 65 percent for most animal types.
  • Methane Conversion Factor: The methane conversion factor defines the portion of gross energy intake that will be converted to methane. The IPCC/OECD Emissions Inventory Guidelines (1994) provide "standard assumptions" to use for this factor. A value of 6.0 percent is commonly used for most well fed animals. Young animals, who nurse for a portion of the year, will generally have a lower value, such as the 3.0 percent shown in the example. These values are entered into LAM using a number code, which is shown in Exhibit 4.

Exhibit 3: Characteristics for Estimating Methane Emissions Factors 

Methane

Feeding

Feeding

Feed

Methane

Methane

Sector

Emissions

Weight

Situation

Situation

Digest

Conversion

Conversion

Sector

Name

Animal Type

(kg/hd/yr)

(kg)

(1-3 above)

Selected

(%)

(1-8 above)

Selected

Milk_1

Urban

Adult Males

54.5

650

1

Stall Fed

60

1

6.0%

Milk_1

Urban

Adult Females

114.8

550

1

Stall Fed

65

1

6.0%

Milk_1

Urban

Repl Males

64.0

350

1

Stall Fed

60

1

6.0%

Milk_1

Urban

Repl Females

53.0

300

1

Stall Fed

60

1

6.0%

Milk_1

Urban

Young Males

14.5

200

1

Stall Fed

65

6

3.0%

Milk_1

Urban

Young Females

12.9

200

1

Stall Fed

65

6

3.0%

Milk_2

Rural

Adult Males

54.5

650

1

Stall Fed

60

1

6.0%

Milk_2

Rural

Adult Females

114.8

550

1

Stall Fed

65

1

6.0%

Milk_2

Rural

Repl Males

64.0

350

1

Stall Fed

60

1

6.0%

Milk_2

Rural

Repl Females

53.0

300

1

Stall Fed

60

1

6.0%

Milk_2

Rural

Young Males

14.5

200

1

Stall Fed

65

6

3.0%

Milk_2

Rural

Young Females

12.9

200

1

Stall Fed

65

6

3.0%

Sectors Milk_3 and Milk_4 are omitted from this exhibit.

Draft_1

Temp

Adult Males

59.4

400

1

Stall Fed

60

1

6.0%

Draft_1

Temp

Adult Females

44.5

300

1

Stall Fed

60

1

6.0%

Draft_1

Temp

Repl Males

29.3

250

1

Stall Fed

60

1

6.0%

Draft_1

Temp

Repl Females

20.3

150

1

Stall Fed

60

1

6.0%

Draft_1

Temp

Young Males

10.6

100

1

Stall Fed

60

6

3.0%

Draft_1

Temp

Young Females

7.1

75

1

Stall Fed

60

6

3.0%

Draft_2

Tropic

Adult Males

59.4

400

1

Stall Fed

60

1

6.0%

Draft_2

Tropic

Adult Females

46.3

300

1

Stall Fed

60

1

6.0%

Draft_2

Tropic

Repl Males

29.3

250

1

Stall Fed

60

1

6.0%

Draft_2

Tropic

Repl Females

20.3

150

1

Stall Fed

60

1

6.0%

Draft_2

Tropic

Young Males

10.6

100

1

Stall Fed

60

6

3.0%

Draft_2

Tropic

Young Females

7.1

75

1

Stall Fed

60

6

3.0%

Meat

All

Adult Males

63.7

650

2

Pasture/Range

60

1

6.0%

Meat

All

Adult Females

71.0

450

2

Pasture/Range

60

1

6.0%

Meat

All

Repl Males

69.3

330

2

Pasture/Range

60

1

6.0%

Meat

All

Repl Females

49.0

330

2

Pasture/Range

60

1

6.0%

Meat

All

Young Males

17.7

200

2

Pasture/Range

60

6

3.0%

Meat

All

Young Females

17.7

200

2

Pasture/Range

60

6

3.0%

Meat

All

Male Slaught

26.5

550

1

Stall Fed

75

5

3.5%

Meat

All

Female Slaught

22.2

500

1

Stall Fed

75

5

3.5%


Note: The methane emissions value is calculated in the model. The values for "Methane Conversion Selected" can be changed by editing the methane conversion factors table on the Methane Characteristics page. Sectors Milk_3 and Milk_4 are omitted from this exhibit.

Exhibit 4: Feeding Situation and Methane Conversion Number Codes

Summary Inputs and Coefficients

Feed Table: Add'l NE required to get feed

1

Stall Fed

0.0%

2

Pasture/Range

17.0%

3

Large Areas

37.0%


Methane Table: Assumed methane conversion of GE

1

Good Quality Feed

6.0%

2

Medium Quality Feed

6.5%

3

Poor Quality Feed

7.0%

4

Very Poor Quality

7.5%

5

Feedlot

3.5%

6

Young (Nursed)

3.0%

7

Milk Fed

0.0%

8

User Defined

6.0%


The number to the left of the appropriate feeding situation or methane conversion factor is entered into the Characteristics for Estimating Methane Emissions Factors Table for each animal type. If needed, additional methane conversion rates can be defined.


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