The only costs considered in the simulation program are those that are directly related to or caused by the cow itself. Whether the herd has 800 or 200 acres, or automated milking system versus rotary parlour, or sand bedding versus wood shavings are in no way related to the genetics of a particular cow. The cow is credited with milk production, and is billed for feed consumed, vet assistance, labour for milking (milking speed), cost of semen, cost of drugs needed, calving assistance, water consumed, calves produced and sold.
Costs should reflect a commercial dairy herd of a particular size, facilities, labour, and management style. Those factors are assumed to not have any impact on the genetic expression of traits of cows, except through culling and breeding criteria. The absolute values should not be too important compared to their relations to each other (e.g. value of milk produced is 1.2 times cost of feed consumed). The table below has some example values.
Variable | Explanation |
Feed cost (DMI basis) | 0.85 per kg |
Water cost | 0.01 per kg |
Milk price | 0.04374 per kg |
Fat price | 9.92 per kg |
Protein price | 7.16 per kg |
Milking labour | 0.15 per min |
Handling labour | 15.50 per hour |
Manure removal | 0.77 per kg |
Calf price(female) | 1.00 per kg |
Calf price(male) | 0.50 per kg |
Cow price | 1.20 per kg |
Replacement heifer | 1220.00 |
Vet Labour | 325.00 per hour |
Young sire breeding | 25.00 |
Proven sire breeding | 35.00 |
CE slight | 40.00 |
CE assist. | 80.00 |
CE hard | 135.00 |
CE caesarian | 400.00 |
The Canadian LPI formula of January 2009 has been used in the program to rank sires and cows for purposes of matings and cullings. Costs of drugs for diseases and amount of milk lost are given under health issues.