Does natural honey act as an alternative to antibiotics in the semen extender for cryopreservation of crossbred ram semen?

ABSTRACT

Antibiotics are added to semen extenders to take care of heavy microbial load, however, their continuous use poses a constant threat of developing antibiotic resistance by the common microbes present in the semen. Our hypothesis was that natural honey, having antibacterial activity and rich in fructose could replace the use of antibiotics and fructose in the semen extender. Twenty-four ejaculates from six crossbred rams were obtained and extended with tris-based extender without (control) and with honey at 2.5% (T1), 5% (T2) and 7% (T3). Sperm quality was measured in terms of percentage sperm motility, live sperm count, intact acrosome and hypo-osmotic swelling test (HOST) reacted spermatozoa. The semen samples at post-thaw were also evaluated for total viable count (colony forming units/ml). At post-thaw, control exhibited significantly (P<0.05) higher sperm motility in comparison to T2 and T3. The percent of live sperm count, intact acrosome and HOST reacted spermatozoa were significantly higher (P<0.05) for control than all other treatment groups at post-thaw. Among treatment groups, T1 maintained significantly higher (P<0.05) percentage of live sperm count, intact acrosome and HOST reacted spermatozoa than T2 and T3. The total viable count at post-thaw was significantly lower (P<0.05) for control than all the treatment groups. In conclusion, honey cannot be used as an alternative to antibiotics to take care of heavy microbial load in semen, however, levels up to 2.5% may be supplemented to semen as an energy source.