Effect of royal jelly as supplementation in feed on sperm progressive motility and histology of testis for rabbits.

Royal jelly (RJ) was applied as a supplement in feed to examine its impact on rabbit buck fertility. The aims were to evaluate the effect of RJ on sperm progressive motility and on histology of testis in rabbits. Twenty male rabbits were divided into four groups, each consisting of five bucks: Control (0mg), T1 {100mg RJ/kg body weight (BW)}, T2 (200mg RJ/kg BW), and T3 (300mg RJ/kg BW), with dietary treatment administered for 8 weeks. Sperm progressive motility (%), testis weight (g) and diameter of seminiferous tubule (µm) were measured. T1 group showed significantly higher (P<0.05) sperm progressive motility and seminiferous tubule diameter compared to the other groups, while an excessive concentration of RJ had a negative impact on the sperm quality, potentially because its components may result in an imbalance in redox reactions due to antioxidative activity. It is concluded that an appropriate dose of RJ improved the reproductive characteristics, but the results do depend on the dose administered to the rabbit. [ABSTRACT FROM AUTHOR]