Effect of two different FSH doses on superovulatory response and embryo production in Sahiwal cows

The aim of the present study was to determine the effect of two different doses of FSH on superovulatory responses in Sahiwal (Bos indicus) cattle. Twelve normal cycling pluriparous Sahiwal cows and weighing between 350 and 420 kg were superstimulated using two different doses of Folltropin-V. Prior to superstimulation, Sahiwal cows were administered estradiol-17? (2 mg, i.m.) with placement of intravaginal progesterone releasing device (TRIU-B) at the random stage of the estrous cycle. On the day 4, cows were administered Folltropin-V @100 in the group 1 and 200 mg of NIH FSH PI in the group 2, divided into 8 tapering doses given at 12 hourly intervals. Prostaglandin F2? analogs (PGF2?) was administered at day 6 and day 6.5, and TRIU-B was removed with the last FSH injection. All cows in both the groups were inseminated twice at 12 and 24 h of LH treatment. Daily ultrasonography was performed to record the size and number of follicles and superovulatory response. No significant difference in number of small follicles (?7 mm) was present at the time of initiation of superstimulatory treatment in both the groups (23.3±3.93 vs. 22.3±1.17, p>0.05). Following superstimulatory treatment, the average number of small follicles reaching ovulatory size (>10 mm) were 18.0±4.04 and 19.2±1.11, respectively, p>0.05 and did not differ significantly. Similarly, total embryos and transferable embryos recovered also did not differ between the group 1 and the group 2 (9.0±4.02 vs. 10.7±2.78, p1>0.05, and 3.5±1.26 vs. 3.3±1.84, p2>0.05, respectively). Results of the present study showed that there is no significance difference in superovulatory response, embryo recovery & number of transferable embryos between Sahiwal cows superstimulated using 100mg or 200 mg of FSH in Sahiwal cows. Keywords: FSH, superstimulation, embryo production M.V.Sc.