Influence of Bacterial Contamination and Antibiotic Sensitivity on Cryopreserved Sperm Quality of Indian Red Jungle Fowl.

Aims: Bacterial contamination may occur in feces during collection and processing of semen. Bacteria not only compete for nutrients with spermatozoa but also produce toxic metabolites and endotoxins and affect sperm quality. The aim of the present study was to investigate the effect of antibiotic supplementation on the sperm quality of Indian red jungle fowl, estimation and isolation of bacterial species and their antibiotic sensitivity. Materials and Methods: Semen was collected and initially evaluated, diluted, and divided into six experimental extenders containing gentamicin (2.5 µg/mL), kanamycin (31.2 µg/mL), neomycin (62.5 mg/mL), penicillin (200 U/mL), and streptomycin (250 µg/mL), and a control having no antibiotics were cryopreserved and semen quality was evaluated at post-dilution, post-cooling, post-equilibration, and post-thawing stages (Experiment 1). A total aerobic bacterial count was carried out after culturing bacteria (Experiment 2) and subcultured for antibiotic sensitivity (Experiment 3). Results: It was shown that penicillin-containing extender improved semen quality (sperm motility, plasma membrane integrity, viability, and acrosomal integrity) compared with the control and other extenders having antibiotics. The bacteria isolated from semen were Escherichia coli, Staphylococcus spp., and Bacillus spp. Antibiotic sensitivity results revealed that E. coli shows high sensitivity toward neomycin, kanamycin, and penicillin. Staphylococcus spp. shows high sensitivity toward streptomycin, neomycin, and penicillin. Bacillus spp. shows high sensitivity toward kanamycin and penicillin. Conclusions: It was concluded that antibiotics added to semen extender did not cause any toxicity and maintained semen quality as that of untreated control samples, and penicillin was identified as most effective antibiotic. It is recommended that penicillin can be added to the semen extender for control of bacterial contamination without affecting the semen quality of Indian red jungle fowl.

Cryopreservation of Indian red jungle fowl (Gallus gallus murghi) semen with polyvinylpyrrolidone.

The Indian red jungle fowl is a sub-species of the genus Gallus native to South Asia; facing high risk of extinction in its native habitat. During cryopreservation, permeable cryoprotectants like glycerol are usually employed and we previously showed encouraging results with 20% glycerol. Because bird spermatozoa contain very little intracellular water, the possibility of replacing an internal cryoprotectant by an external one is opened. In the present study, we tested the replacement of internal cryoprotectant glycerol by the external cryoprotectant Polyvinylpyrrolidone (PVP). PVP is a non-permeable cryoprotectant and keeps the sperm in glassy state both in cooling and warming stages without making ice crystallization within the sperm cell. We evaluated the effect of various levels of polyvinylpyrrolidone (PVP) on Indian red jungle fowl semen quality and fertility outcomes. The qualifying semen ejaculates collected from eight mature cocks were pooled, divided into five aliquots, diluted (37 °C) with red fowl semen extender having PVP [0% (control) 4% (w/v), 6% (w/v), 8% (w/v) and 10% (w/v)]. Diluted semen was cryopreserved and stored in liquid nitrogen. The whole experiment was repeated/replicated for five times independently. Sperm motility, plasma membrane integrity, viability and acrosome integrity were recorded highest (P < 0.05) with 6% PVP at post-dilution, cooling, equilibration and freeze-thawing. Higher (P < 0.05) no. of fertile eggs, fertility, no. of hatched chicks, percent hatch and hatchability was recorded with 6% PVP compared to control. It is concluded that 6% PVP maintained better post-taw quality and fertility of Indian red jungle fowl spermatozoa than glycerol and can be used in routine practice avoiding the contraceptive effects of glycerol.