How to Increase Post-Thaw Semen Quality in Poor Freezing Stallions: Preliminary Results of the Promising Role of Seminal Plasma Added after Thawing

Approximately half of all stallions are considered poor freezers, which means that they produce ejaculate with poor cryopreservation tolerance. Although the quality of the frozen–thawed semen of poor freezing stallions is low, they can carry and transfer desirable traits to future generations via insemination. Therefore, increasing the post-thaw quality of cryopreserved semen from these stallions is an important step in efficient horse breeding. In this study, we aimed to find a way to increase the quality of cryopreserved semen from poor freezing stallions. We studied the effects of different seminal plasma (SP) additions on various functional parameters of spermatozoa. The results show that the addition of different types of seminal plasma positively affects motility and maintains the status of the plasma membrane of poor freezing stallions. Since the percentage of stallions with poor freezability is quite large, future research should target the discovery of specific seminal plasma components that could be used to increase the post-thaw quality of their spermatozoa