Effect of repeated dual superovulation using FSH and PMSG+FSH on ovulatory response in Murrah buffalo

The current experiment was conducted to determine the ovulatory response of Murrah buffaloes subjected to repeated therapeutic doses of FSH and PMSG+FSH in two successive periods. Three elite, multiparous, Murrah buffaloes, 80 to 120 days postpartum, were included in multiple-ovulation embryo transfer (MOET) schedule. The estrus was synchronized with one injection of prostaglandin. Superovulatory treatment was started from day 10 of induced estrus after ablation of dominant follicle of over 10 mm diameter, using 5.0 MHz convex-array intravaginal transducer using a B-mode scanner with aspiration assembly. Study was undertaken in two consecutive periods so each animal was treated with PMSG+FSH in first superovulation period and FSH on the Second period after short interval period (14 day cycle). For FSH treated, Folltropin was administered in a twice-daily descending dose schedule (0–5, 5–4, 4–3, 3–2, 2–2 ml; 20 mg/ml, total dose 600 mg of FSH. For PMSG+FSH treated, an injection of PMSG (1000 IU) was given in the evening of day 10 followed by dose 400 mg FSH and schedule as of FSH treated group from the evening of day 11. All donors received prostaglandin injection on day 13 in morning and evening. Donors were inseminated with frozen thawed semen of proven bull on Day 15 a.m. and p.m. and Day 16 a.m. Nonsurgical embryo collection was carried out on Day 5 post-insemination. There were no differences between the mean numbers of follicles in the same buffaloes treated with PMSG+FSH or FSH at any time throughout the experimental period. At AI, similar numbers of corpora lutea were observed for PMSG+FSH and FSH. On the day of flushing, almost similar mean numbers of corpora lutea counted in PMSG+FSH and FSH treated buffaloes In conclusion, ovarian response in Murrah buffaloes treated with PMSG+FSH or FSH for two superovulatory periods were nonsignificantly different.