COSTS OF MILK HARVEST IN DAIRY-CATTLE - IMPLICATIONS FOR DIRECT SELECTION AND COW CULLING

Labor and machine costs of milking were derived from data on Holstein and Jersey cows to determine their importance for direct selection and culling. The labor cost of milking Holsteins ranged from $.16 to $.27/day for milk yields when labor was valued at $4.50/h. Machine stripping comprised about one-third of this labor cost. Effects of lactation number for labor and machine costs were small, $.05 and $.02/day, for cows of same yield and stage of lactation. Standard deviations of labor and machine costs of milking Holstein cows were $13.39 and $7.25/305-day lactation. Variation in labor or machine costs was insufficient to warrant direct selection for improved economy of milking. Parity of cow could contribute to a decision to cull in extreme cases of low production and high labor and/or machine requirements but is otherwise inconsequential. © 1979, American Dairy Science Association. All rights reserved.