Does royal jelly have a reproductive effect on progesterone-treated goats?

Abstract

Introduction: Some methods for inducing/synchronizing oestrus and ovulation in goats require the injection of equine chorionic gonadotrophin (eCG). The objective of this study was to determine whether royal jelly (RJ) can be a subs-titute for eCG in CIDR-treated dairy goats. Methods: Sixty-six primiparous goats received the CIDR device for twelve days in April. The eCG group (n=22) was injec-ted with 200 IU of the gonadotropin when the intravaginal device was removed; the RJ group (n=22) received a daily intramuscular injection of 1 g of RJ during the period of CIDR treatment; the CIDR group (n=22) did not receive any additional treatment. A fourth group (Con, n=20) was used as control and received no treat-ment at all. Oestrus response, ovulation and fertility were recorded. Results: The oestrus percentage was higher in eCG (95%, p<0.05) than in the remaining groups (RJ, 41%; CIDR, 36% and Con, 0%) and occurred at shorter intervals (eCG, 35±2.3; RJ, 66±4.6; CIDR, 59±2; h±se; p<0.05). Ovulation was higher in eCG (91%, p<0.05), and RJ and CIDR were not different between them (50% vs 41%, p>0.05). No ovula-tion was recorded in the Con group. The percentage of fertile and birthing animals after 148-158 days was greater in the eCG (91%, p<0.05) compared to other groups (RJ, 36%; CIDR, 36%, Con, 0%), whereas it was not different between the RJ, CIDR and Con groups (p>0.05). Conclusion: There was no evidence of a reproductive effect of RJ on progesterone-treated goats.