Effect of anti-oestradiol-17B antibodies on the reproductive response of ewes superovulated with PMSG.

A field experiment was conducted to examine the effect of anti-oestradiol-17B antibody titre on the oestrous and ovulatory responses of ewes to low (600 i.u.) or high (1200 i.u.) doses of pregnant mare's serum gonadotrophin (PMSG). Merino ewes were treated with intravaginal sponges and were subsequently used as vehicle-treated controls or were immunized to produce reciprocal anti-oestradiol- 17B antibody titres of 1000. Ewes were then treated with PMSG and the incidence of oestrus and ovulation, ovulation rate, and yield of embryos recorded.