Preliminary report on induction of estrus with multiple eCG injections in Colored Mohair goats during the anestrus season

This trial was conducted to evaluate the effectiveness of multiple eCG injections in the induction of estrus and pregnancy in Colored Mohair goats during the anestrus season. It was also aimed to determine total dose of eCG required for induction of estrus. Ten multiparous and lactating goats were used. The goats were randomly divided into two groups and treatments were started on May 22. Group eCG (n = 5) was treated with eCG intramuscularly for 6 days. Daily dosages of eCG from May 22 to May 27 were 300 IU, 200 IU, 200 IU, 100 IU, 100 IU and 50 IU, respectively. Goats in control group received no treatment. Blood samples were taken from animals in each of the two groups just before and after the beginning of the treatments and serum progesterone concentrations were assayed by RIA. Starting on the fourth day after the first treatments, goats were exposed to fertile bucks twice daily for 30 min to detect standing heat. The estrus goats were allowed to be mated by the bucks. Pregnancies were determined 40 days after mating by real-time ultrasonography. One goat on day 5 and three goats on day 7 exhibited behavioral estrus in eCG group (80%) after the first eCG injection. Three of them (75%) became pregnant. None of the goats in the control group exhibited behavioral estrus. Mean serum progesterone concentrations had prominent elevations indicating ovulation in eCG group, but not in control group, after 20 days from the first treatments. Progesterone concentrations of eCG group were significantly different than those of control group on days 20 and 28 (P < 0.05). The results suggest that divided multiple injections of a total 950 IU eCG are effective without progestagen pretreatment in the induction of estrus and obtaining successful pregnancy and live kids in Colored Mohair goats during the anestrus season.