Effect of Testosterone, Dihydrotestosterone, Estradiol, and Cortisol on the Quality of Fresh and Cryopreserved Stallion Sperm

This study on 40 stallions of various breeds examined the impact of testosterone, dihydrotestosterone, estradiol, and cortisol on the quality of fresh and cryopreserved sperm. It found that higher testosterone levels negatively correlated with both total and progressive sperm motility in both fresh and cryopreserved samples. Conversely, higher estradiol levels positively correlated with sperm survival rates in both conditions. Dihydrotestosterone levels were positively associated with ejaculate volume and total sperm count. Cortisol levels showed no significant correlation with sperm quality. The findings suggest that steroid hormone concentrations should be considered when selecting stallions for sperm cryopreservation.