The effect of bovine interferon-alpha I1 on pregnancy rate in heifers.

摘要: Bovine interferon-alpha I1 (bIFN-alpha) may be useful for enhancing fertility in sheep and cattle because it has extensive sequence homology with ovine bovine trophoblast protein-1 and, like those proteins, extends corpus luteum lifespan. To test the effectiveness of bIFN-alpha to enhance fertility, several experiments were performed which inseminated heifers given i.m. injections approximately at time embryo-mediated signals that result maintenance luteum. In Exp. 1, 20 mg daily from d 14 17 tended (P less than .07) have lower pregnancy rates 110 112 gestation (36/75; 48% vs 43/72; 60%). Similar results obtained 2 when received a single injection 40 or placebo 13 after estrus; 42 39/104 (38%) 47/98 (48%) placebo. 3, gradually increasing doses 11 19, such regimen had been shown reduce number experiencing hyperthermia injection. Pregnancy 42/95 (44%) 62/111 (56%) Across all three experiments, .01) treated (117/274; 43%) (152/281; 54%). conclusion, these demonstrate that, under administration systems used, does not increase rate, but rather tends it.