Fertilitily of frozen equine semen with addition of pentoxifylline

Abstract

Equine reproduction has increasingly sought to maximize the use of semen through artificial insemination, using semen diluted fresh, cooled and frozen. However, there are still many challenges in the use of these three modalities, which include the manipulation, conservation and deposition of semen in the female's reproductive tract. Pentoxifylline has been studied as an enhancer of sperm motility, acting as a phosphodiesterase inhibitor, increasing levels of intracellular cAMP, a molecule involved in the generation of energy by sperm. However, it is not clear whether improved sperm motility translates into better fertility rates after artificial insemination. Therefore, this study aims to assess fertility of frozen semen with the addition of pentoxifylline. For the experiment, two stallions and two treatments will be used (control and treated with pentoxifylline). For this, the semen will be frozen with BotuCrio® extender, in 0.5 ml straws. Eleven estrous cycles will be used for each treatment and stallion, with a total of 44 artificial inseminations (2 stallions x 2 treatments x 11 A.I.). After thawing, 7.18 mM (1.9 mg / mL) pentoxifylline will be added to the semen of the treated group. Analyzes of sperm motility by the CASA system, as well as collection of semen samples to perform sperm morphology (DIC). The data obtained from the experimental procedures will be analyzed using the Statistical Analysis System for Windows SAS® software, version 9.3 (SAS, 2005). Thawed semen containing pentoxifylline is expected to show better fertility results after artificial insemination.