Impact of royal jelly to improve reproductive performance of male rabbits under hot summer conditions

Abstract

[EN] To alleviate the deleterious effect of heat stress during summer conditions on male rabbits’ reproduction, 40 V Line adult rabbit bucks (on av. 8 mo old) were divided into 4 experimental groups and exposed to temperatures ranging from 23 to 36°C. Bucks in the 1st, 2nd, 3rd, and 4th group were supplemented with 0, 50, 100 or 150 mg of Chinese royal jelly (RJ)/kg twice per week, respectively, over a 20-wk period. Semen quality and blood biochemical constituents were evaluated. RJ at any dose exhibited a significant increase (P<0.05) in rabbits’ sperm concentration, total sperm output, sperm motility, live sperm and normal sperm compared to the untreated controls. Plasma total protein, albumin, globulin, glucose and high density lipids (HDL) concentrations were significantly (P<0.05) boosted in the RJ groups compared to the controls. In contrast, RJ treatment resulted in a significant (P<0.05) reduction in plasma total lipids, triglycerides, cholesterol and low density lipids (LDL) concentrations. Treatment with RJ significantly boosted (P<0.05) testosterone concentration in the RJ groups to reach 110, 120 and 128%, respectively, of the control group. Improved kidney and liver functions were observed in the RJ bucks groups where plasma creatinine, urea concentrations, aspartate aminotransferase and alanine aminotransferase enzyme activities were significantly (P<0.05) decreased by RJ treatments. Treating bucks subjected to heat stress by different RJ doses increased (P<0.05) total antioxidant capacity to 106, 111 and 115% of basal, but significantly reduced (P<0.05) malondialdehyde and thiobarbituric acid reactive substances compared to the untreated. It was concluded that Chinese royal jelly supplementation for heat-stressed male rabbits can counteract summer infertility and improve their physiological status.