Use of coenzyme Q-10 to improve the pregnancy rate in sheep

Abstract

One of the factors responsible for less pregnancy rates is the use of frozen semen in sheep due to the oxidative stress created by the process. The aim of this experiment was to test the effects of adding coenzyme Q-10 (CoQ10) to the seminal extender on sperm quality and the pregnancy rate of sheep. In this study, ejaculates from eight Dorper rams of reproductive age were used and tested in four treatments: Control (pure BotuBov®), C1 (175 µM of CoQ10), C3 (350 µM of CoQ10), and C7 (700 µM of CoQ10). Samples were collected in triplicate from each animal, and sperm analysis was performed by CASA after thawing at 0 h and 2 h. The samples were also analyzed by flow cytometry for plasma and acrosomal membrane integrity, stability, lipid peroxidation, mitochondrial potential, and superoxide anion production. In total, 198 ewes were inseminated by laparoscopy and divided into two groups: control (n=98) and C7 (n=100). Pregnancy diagnosis was performed at 30 days. Coenzyme Q10 proved to be safe for semen cryopreservation, not altering sperm kinetic values between the groups post-thawing. In flow cytometry, the C1 and C7 groups achieved a better index of plasma membrane integrity and membrane stability (P<0.05). A increased pregnancy rate was observed in C7 (52 %) compared to the control (38 %). In conclusion, coenzyme Q10 assists in the cryopreservation process, protecting the sperm cell and improving pregnancy rates in ewes.