Effect of royal jelly on bovine sperm characteristics during post–thaw incubation in vitro

Abstract

Cryopreserved bovine semen is generally considered to have lower fertility compared to fresh semen. The reduction arises from both a lower post–thaw viability and a possible sublethal dysfunction of the surviving sperm population. The present study was conducted to observe the effect of royal jelly (RJ) on motility, viability and acrosome integrity of spermatozoa during post–thaw incubation. Frozen–thawed semen samples were washed and incubated at 37°C in Tris buffer containing 0.1, 0.2, 0.3, 0.4, 0.5% RJ or none (control). Sperm motility, viability and acrosomal integrity were assessed at 0, 0.5, 1, 1.5 and 2 h. The percentages of sperm motility, viability and intact acrosome were higher in Tris buffer containing 0.4% RJ compared to control (p < 0.05). After 2 h of incubation the percentages of motility, viability and intact acrosome of spermatozoa, respectively, were 52.3; 52.5 and 19.8% in 0.4% RJ containing buffer. Results indicate that the addition of 0.4% RJ in the incubation media was able to maintain better quality and longevity of spermatozoa. Royal jelly may be used as a semen extender to improve sperm quality and fertility.