The Effects of Short or Long Term FGA Treatment with or without eCG on Reproductive Performance of Ewes Bred Out-of-season

摘要: The objective was to evaluate the effects of intravaginal FGA sponges inserted for 4 or 12 days with without eCG on reproductive performance ewes out-of-season. Forty-eight anestrous were assigned in equal numbers four treatments a 2x2 factorial design. Ewes administered May 17 (12-day-FGA-eCG and 12-day-FGA groups, n= each) 25 (4-day-FGA-eCG 4-day-FGA each). All timed end together 29 (day 0, 0 h) at which time withdrawn saline injected. Five fertile rams had been isolated from joined h breeding estrus detection. Blood samples collected compare progesterone (P4) concentrations pregnancy diagnosis. Overall expression occurred 40/48 differed only between 12-day-FGA-eCG (p 0.1) increased gradually thereafter until day 15. Progesterone remained elevated through 19 11/12, 8/12, 9/12 6/12 ewes, respectively, diagnosed pregnant 30 by ultrasonography. Of 34 that became pregnant, 31 lambed 150 following 0. Pregnancy loss 3 two groups did not have treatment No differences lambing rates number lambs born found eCG. overall obtained mating first service 70.8 64.6%, respectively. In conclusion, regimen could adequately replace Application such protocol must be accompanied upon sponge removal.