Effect of passive immunization against synthetic inhibin peptides on estrus response and ovulation rate in Malpura ewes Naqvi S.M.K., Joshi Anil, Gulyani R., Kumar Davendra Division of Physiology, Central Sheep and Wool Research Institute, Avikangar via Jaipur (Rajasthan) India, 304 501. E-mail address: naqvismk@yahoo.co.in. Abstract The objective of the present study was to examine the effect of passive immunization against synthetic peptides i.e., a 30-mer peptide based on the αC [bIα(1–29)-Tyr30] (Group I), a 17-mer peptide based on the αN region [bI-43-Tyr152(153–167)Cys168] (Group II) of the α-subunit of bovine inhibin conjugated to ovalbumin and a control ovalbumin group (Group III) on estrus response and ovulation rate in Malpura ewes. Eighteen adult Malpura ewes were assigned equally to three treatment groups. All the ewes were synchronized for estrus with the use of two doses of PG F2α (PGF) administered at 10 days interval. On day 10 of the second dose of PGF (day 1), 10 ml of ovine immune sera that had been generated by active immunization against 30-mer and 17-mer peptides and serum from control group was injected in the ewes in the treatment Group I, Group II and Group III, respectively. All the ewes were again synchronized for estrus by administering third dose of PGF on day 13 and estrus responses were recorded. Passive immunization did not affect the onset interval and duration of estrus. All the ewes exhibited estrus within 60 h of last PGF injection. The duration of estrus ranged from 24 to 42 h. Ovarian examination performed by laparoscopy on day 3–4 of the estrous cycle, revealed that the ovulation rate in Group I, Group II and Group III were 1.7 ± 0.3, 1.2±0.2 and 1.0±0, respectively. The results indicated that passive immunization against synthetic inhibin peptides did not affect the estrus response in Malpura ewes but relatively higher ovulatory response was observed by administering antisera generated against 30-mer peptide as compared to 17-mer peptide. Top Key words Estrus response, Inhibin, Malpura, Ovulation rate, Passive immunization, Sheep. Top |