LACTATION CURVES FOR 1ST LACTATION EGYPTIAN BUFFALO

First lactation records of 1538 buffalo maintained at the Animal Produ ction Research Institute farms in 1967 to 1990 were used to determine lactation curves for three lactation lengths: >28 and <150 d, >149 d, and greater-than-or-equal-to 308 d, as well is all records. Daily milk yields were summed by 14-d intervals for analyses. Yields peaked at t he first, fifth, sixth, and seventh periods for >28 and <150 d, >149 d , greater-than-or-equal-to 308 d, and all records. Herd-year-season si gnificantly affected milk yield in all periods. Persistency for all re cords and three groupings (>28 d, >149 d, and greater-than-or-equal-to 308 d in milk) was highest for the greater-than-or-equal-to 308-d gro up (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 buf falo calving in spring and summer for all records, records >28 d, and records >149 d but in summer and autumn for the greater-than-or-equal- to 308 d records. In records greater-than-or-equal-to 308 d, the corre lation coefficient between persistency and milk yield (r = .06) was no t significant but was negative with season of calving (r = -.11).