Prediction Time of Ovulation of Etawah Grade Goats after Synchronization by Short Term Controlled Internal Drug Release

Abstract

Fourteen Etawah crossbred goats with BCS 3 and body weight around 30 to 40 kg were used in these studies.The study of onset estrous and duration of estrous used 10 head of Etawah crossbred goats (n=10). The study was aimed to determine the concentration of estradiol and LH used 4 head Etawa crossbred goats (n=4). All does were synchronized using implant intravagina Controlled Internal Drug Release (CIDRg, Pharmacia & Upjohn Pty Limited, NSW) in ten days and injected by prostaglandin F2 (125 μg Cloprostenol, Juramet®, Jurox, Australia) at 48 hour before CIDR removal. Estrous was detected using vasectomy buck. Respons of estrous was 100 %. Onset of estrous was 26.59±0.98 h and duration of estrous was 35.6± 2.6 h. Mean concentration of estradiol on estrous period range between 32.22 ± 22.23 pg/mL to 89.91 ± 92.84 pg/ mL, the highest concentration was 89.91 ± 92.84 pg/mL at 42 h after CIDR removal or at 16 h after onset of estrous. LH surge occurs at 45 h, 48 h and 51 h after CIDR removal with the concentration of LH were 9.9± 9.1 ng/mL; 4.5± 4.0 ng/mL; and 18.2± 9.1 ng/mL respectively. Follicle diameter before ovulation in Etawah crossbred goats was 11.41 ± 1.67 mm. In conclusion, it can be predicted that time of ovulation in Etawah crossbred goats occurs from 51 h to 62 h after CIDR removal or from 25 h to 36 h after onset of estrous. Keywords : Etawah Crossbred Goats, Estrous Synchronization, CIDR-g, Estradiol, LH