Improving Ovulation and Conception Rates in Oestrus Synchronized and Artificially Inseminated Water Buffaloe Cows by Immunization Against Inhibin

This study aims to improve conception rate of water buffalo cows by immunization against inhibin. Eleven multi-parity buffaloes cows were i.m. immunized with inhibin immunogen (2 mg of inhibin a subunit protein in mineral oil adjuvant), and another 13 animals served as adjuvant treated controls. Following Ovsynch treatment, inhibin-immunized cows showed stronger expression of oestrus (72% vs 30%, P<0.05), and had more developing follicles, higher number of corpora lutea (0.9 +/- 0.1 vs 0.5 +/- 0.1, P<0.05), than did the control animals. In addition, 40 days after artificial insemination, the conception rate was markedly higher in immunized group than that of in the control group (45.5% vs 15.4%, P > 0.05). These results indicated that immunization against inhibin, through promoting development and functions of ovarian follicles and corpora lutea (CL), apart from oocyte and embryo qualities, may improve reproductive performance or conception in water buffalo cows.