| Popis: |
First lactation records of 1538 buffalo maintained at the Animal Production Research Institute farms in 1967 to 1990 were used to determine lactation curves for three lactation lengths: >28 and 149 d, and ≥308 d, as well as all records. Daily milk yields were summed by 14-d intervals for analyses. Yields peaked at the first, fifth, sixth, and seventh periods for >28 and 149 d, ≥308 d, and all records. Herd-year-season significantly affected milk yield in all periods. Persistency for all records and three groupings (>28 d, >149 d, and ≥308 d in milk) was highest for the ≥308-d group (1.02 vs. .85 for >149 d, .57 for >28 d, and .47 for all records). Herd-year-season of calving significantly affected persistency in all records and the three subset groupings. Persistency was higher for buffalo calving in spring and summer for all records, records >28 d, and records >149 d but in summer and autumn for the ≥308 d records. In records ≥308 d, the correlation coefficient between persistency and milk yield (r = .06) was not significant but was negative with season of calving (r = –.11). |
