Peripheral Progesterone Level and Times to Estrus and Ovulation in Female Dromedary Camels Treated with CIDR-eCG-hCG Programs

Abstract

This study was conducted to characterize serum progesterone (P4) profiles during CIDReCG- hCG superovulatory program and to investigate the effect of time of eCG administration on the superovulatory response in dromedary camels. Controlled internal drug release (CIDR) was inserted intravaginally for 14 days in eleven dromedary females. Two days before CIDR withdrawal, group 1 (n=6) received 3000 iu eCG im, group 2 (n=5) received the same dose at CIDR withdrawal. All received 1500 iu hCG two days after CIDR withdrawal (d+2). Animals were observed for estrus and mated with a fertile male. Serum was obtained for progesterone. The ovaries were examined using ultrasound. An increase in serum P4 was observed within 20min of CIDR insertion with peak level attained by 4h (P<0.0001). There were no differences in P4 between group 1 and 2. Estrus and ovulation occurred nonsignificantly earlier in group 1 (4.8±0.9d and 8.2±1d) than in group 2 (6±0.7d and 9±1d), respectively. Number of corpora lutea by d+14 did not differ between group 1 (4.6±0.7) and group 2 (5.2±1.5). In conclusion, early administration of eCG did not hasten estrus or ovulation or the function of the CLs in super-stimulated female dromedaries compared with its administration at the time of CIDR withdrawal. These data may help in designing fixed time superovulation programs in dromedary camels.