Effect of stimulation with a gonadotropin mixture on reproductive outcome in nulliparous ewes bred during seasonal anestrus and early breeding season.

To evaluate the effect of gonadotropic stimulation on the reproductive response of nulliparous acyclic female sheep during mid-anestrous and early breeding season, fall-born ewe lambs of mixed breeding (N=191; ∼7 months old; study 1) and yearlings (Dorset X Texel (DT), N=120, study 2) were assigned randomly during May to July to be either pre-treated with progesterone using CIDR-g (0.3g of progesterone) devices for 5 days or to also receive gonadotropins (240IU eCG and 120IU hCG, 3mL i.m.