Efficacy and Safety of Different Antimycotic Formulas Used in Sheep Frozen Semen Extenders

This study aimed to select a potent and more safe antimycotic as additive to cryodiluents of sheep frozen semen. Semen samples were collected from 6 Barki rams and processed for cryopreservation after adding different concentrations of griseovulvin, clotrimazole, nystatin, fluconazole or amphotricin-B, each alone, to semen diluent. Sensitivity of Candida albicans and Cryptococcus neoformans to antimycotic drugs were studied. Results showed that fluconazole and nystatin (at dose of 2.5, 25 50 mg/L) had no deleterious effect on sheep semen freezability. Higher doses of amphotricin-B and griseofulvin resulted in drastic deterioration of frozen semen quality. Candida albicans and Cryptococcus neoformans were sensitive to fluconazole and amphotricin-B and resistant to lower concentrations of griseovulvin and clotrimazole. Conclusively, addition of fluconazole to sheep semen diluent has a benefit of improving the quality of yeast contaminated sperm with no bad effect on the frozen-thawed semen quality.