生物学と医学

概要

Estrus induction and fertility response in anestrus mares with exogenous progesterone releasing device (CIDR-B) during late breeding season

Kumar R, *Phogat JB, Mann JS, Singh U, Sharma AK

The present study was conducted with 25 lactational anestrus mares during late breeding season (July/August) dividing randomly in Treatment (n=15) and Control Groups (n=10). In Treatment Group, a progesterone releasing intra-vaginal device (CIDR-B) was inserted in the vagina and placed in situ for a period of 12 days and on the day of removal PGF2 (3 ml Ilerin i/m) was injected. In Control Group, no treatment was given. Blood samples were collected for progesterone estimation at the time of CIDR-B insertion (day 0), day 4 and 8 after CIDR-B insertion, on the day of CIDR-B removal (day 12), on the day of covering and day 12 after covering. At corresponding days, blood samples were also collected from Control Group. After CIDR-B removal, the reproductive performance of mares was recorded up to 20 days in terms of estrus induction response and pregnancy rates. In mares, which were having initial basal progesterone levels (1.64  0.19 ng/ml) on the day of device insertion, the levels significantly (p