Reproductive performance of Iraqi buffaloes. I. Pattern of female reproduction.

In a buffalo herd at Amara Buffalo Breeding Station between October 1975 and October 1976 various features were investigated of the reproductive performance of heifers. The average age of the heifers was 22.01 at first estrus, 22.50 at ovulation, 26.05 at conception, and 38.8 months at calving. Estrus occurred at an average interval of 72.7 days after calving. Extended post-partum anestrus for more than 90 days was observed in 26.8% of the animals studied. The average length of the calving interval was calculated as 408 days. 67.3% of the calvings took palce between June and October.