Abstract

Active immunisation of Romney ewes with bovine follicular fluid (bFF) at monthly intervals for 4 months in the breeding season increased monthly mean ovulation rates by 8 to 100%, relative to non-immunised ewes, by increasing the frequency of double ovulations. The increases in ovulation rate were independent of the dose of bFF (from 1 to 10 ml) and whether an aqueous- or oil-based adjuvant was used. Immunisation with porcine FF (1 or 5 ml) did not increase ovulation rates significantly. Active immunisation with an androstenedioned-based immunogen (Androvax), increased the mean monthly ovulation rates 31 to 63% by increasing the frequency of double and triple ovulations. Immunisation with bFF and Androvax together did not increase ovulation rates any more than immunisation with Androvax alone. These results show that active immunisation with bFF can increase ovulation rates in sheep, though generally less effectively than by immunisation with an androstenedione-based immunogen.

PJ, L'Huillier, SR Davis, VR Carruthers, CA Morris, and AM Bryant

Proceedings of the New Zealand Society of Animal Production, Volume 49, , 57-64, 1989