Age-parity-season adjustment factors for milk and fat yields of dairy goats.

Dairy Herd Improvement records from 1976 through 1981 were used to obtain dairy goat age-parity-season adjustment factors for milk and fat yields. Only records from purebred and American Alpine, Nubian, Saanen, and Toggenburg does were used. Nubians were analyzed separately from other breeds. Factors were calculated for two parity groups, two seasons, and two regions. Mixed model equations were used to remove effects of doe, breed, and year. Only lactations of at least 120 days were used. Resulting curves showed maximum production between 24 and 50 mo of age. Does from the northeastern United States reached maximum production earlier than does from western states.