The Effect of hCG or Receptal During Diestrous and Proestrous in the Synchronization, Super Ovulation Corpus Luteum (CL) Development in Buffaloes Cows

This study was managed to evaluate synchronization, super-ovulatory responses, corpus luteum (CL) development in buffaloes. Hundred -three cyclic, non lactating buffaloes (Murrah) were hCG versus 2.5 ml of receptal (Hoechst) containing 0.01mg/2.5ml Buserelin injected intra muscularly (Gn-RH) during diestrous and proestrous. In Experiment 1, 55 buffaloes received a vaginal sponge of a 3 mg synthetic progestogene, norgestomet for 14 d to achieved estrus synchronization (day 0), with PG F2? after vaginal sponge removal. 5 days after vaginal sponge insertion, all follicles ?10 mm were ruptured, 14 days after vaginal insertion, buffaloes injected either with 3, 4,5 cc hCG or 2.5 ml of receptal. On day 14, The ovulatory response to5 cc hCG (82%) or 100 ?gGnRH (70%) compared to 3cc hCG (31%) was showing significantly greater response, but not significantly different from that of 4cc hCG (56%). In Experiment 2, days 7after after estrus signs, those buffaloes injected with PGF, and, 36 hr later with hCG or receptal (as in Experiment 1). Buffaloes presented in both experiments ? and ?? were received 75 NIH units of Super-Ov in a descending dose schedule spread over the first 3 days (twice daily) after ovulation (day 0). The ovulation time was most variable among buffaloes given3cc hCG compared to 4, 5 cc hCG or 2.5 ml receptal; only 50% of 5 cc hCG (P < 0.05) injected buffaloes ovulated during the initial 24 hr of estrous sign. Buffaloes injected with 5 cc hCG or 2.5 ml of receptal had larger CL compared to those injected with 3cc hCG . This study concluded that, the diestrous buffalo cows injected with 5 cc hCG their ovulatory response did not differ from that of those injected with 2.5 ml of receptal. Proestrous buffaloes given 5 cc hCG or 2.5 ml of receptal, their ovaries showing larger CL compared to those injected with 3cc hCG. Immediately after first mating each buffalo cow was administered either with 2.5 mL of receptal or 3, 4, 5 cc of hCG to ensure that the buffaloes ovulated. Non surgically embryos collection was done on Days 6 and 7 after buffaloes showing estrus signs (Day0) and then collected embryos were subjected to comparative studies. A majority of buffaloes cows (19/24) exhibited estrus within 8 hr after vaginal sponge removal . The adverse affect of heat stress on the number of CL, unovulated follicles and overall ovarian activity, estrus behavior, super ovulation and embryos quality for summer and winter seasons were recorded for buffaloes during the summer and winter seasons.