Factors affecting standardized milk and fat yields in Alpine goats

R. Browning, Jr., M.L. Leite-Browning and T. Sahlu

Records from 499 lactations of 220 Alpine does were evaluated to test lactation year, lactation number, and litter size effects on 305-day adjusted mature equivalent milk and fat yield was greater (P<0.01) in 1986 (968 kg) than in following years (range 777-845 kg). Fat yield was not influenced by lactation year. Positive (P<0.01)associations were found when phenotypic merits for lactation yield were regressed on birth year and generation. Lactation number affected (P<0.01) milk yields with production highest at second lactation (960 kg) and lowest at seventh lactation (634 kg). Does delivering single kids had lower (P<0.01) coefficient was computed (775 kg) than does delivering twins and triplets (834 and 903 kg, respectively). A positive (P<0.01) coefficient was computed (17.5 ± 4.5 kg litter weight) when milk yield was regressed on total litter weight. Fat yield was similarly affected (P<0.01)by lactation number and litter characteristics. Unique were results showing that litter size and litter weight had positive relationships with lactation yields in does despite the removal of kids at birth.