Reproductive efficiency of Egyptian buffaloes in relation to oestrous detection systems

A total of 57 buffalo cows were divided into two groups and subjected to different intensities of oestrous detection. In the first group (G1), oestrus was checked at 6-h intervals, four times daily starting at 0600 h as compared to twice daily in the second group (G2) at 0800 h and 1500 h. The year was also divided into two seasons: cool from November to April; and hot from May to October. Ovulatory activity was monitored by measuring progesterone concentrations in blood serum. Samples were obtained every 3 or 4 days post-partum until conception was confirmed. More frequent detection practices produced shorter intervals for all of the reproductive parameters. Calving interval was less for cows in G1 in the cool season (363.5±16.0 vs. 400.3±14.3 days) than in the hot season (387.0±15.3 vs. 441.5±14.3 days). Oestrous detection efficiency was higher (P<0.01) in G1 in both seasons. Season of calving produced a significant effect (P<0.05) on the number of services per conception. The cool season calvers had better reproductive performance than cows calved during the hot season.