Superovulation of dromedary camels with eCG: An effective and practical technique

This study was conducted to develop simple superovulation protocols for dromedary camels using eCG. In experiment 1, camels received either 1000, 2000, 3000, 4000, 5000 or 6000 IU eCG. In experiment 2, camels received either 400 mg FSH (Folltropin-V) twice-daily over 5 days or 3000 IU eCG. In experiment 3, camels received 3000 IU eCG either at 2, 3, 4 or 5 days after ovulation induction. Ovarian response and embryo yield were evaluated in all experiments and embryos collected from camels treated with FSH and eCG were transferred to recipients to examine pregnancy rates. The mean number of ovulations (12.6 +/- 1.5 and 13.3 +/- 1.2 vs 3.4 +/- 0.3, 6.2 +/- 0.6 and 9.3 +/- 1.0, respectively) and transferable embryos (4.6 +/- 1.3 and 4.8 +/- 1.0 vs 1.6 +/- 0.2, 2.2 +/- 0.4 and 1.1 +/- 0.4, respectively) with 3000 and 4000 IU eCG doses were higher compared to 1000, 2000 and 6000 IU eCG doses (P < 0.05). Doses of 5000 and 6000 IU eCG resulted in a higher number of unovulatory follicles than other doses (P < 0.05). The FSH treatment resulted in higher number of ovulatory follicles (21.8 +/- 1.3 vs 14.8 +/- 1.7) and ovulations (18.5 +/- 1.1 vs 13.9 +/- 1.4) compared to eCG (P < 0.05). However, the number of transferable embryos and pregnancy rates were similar in these treatments. The timing of eCG treatment after ovulation induction did not affect the number of ovulatory follicles and transferable embryos but eCG treatment at 5 days after ovulation induction reduced the number of ovulations (P < 0.05). In conclusion, the optimal dose of eCG to induce superovulation is 3000-4000 IU and it produces a comparable embryo yield to FSH, and can be administered at 2-4 days after ovulation induction. (C) 2020 Elsevier Inc. All rights reserved.