Use Low Ozone Dosages has Positive Effects on the Cooling and Cryopreservation of Equine Semen

Abstract

The aim of this study was to determine an ozone dosage capable of inducing pro-oxidation, and to verify its action on sperm cells during the process of cooling and cryopreservation of equine semen. In this study, we evaluated the ozone concentrations of 2µg/mL,15µg/mL, 30µg/mL e 60 µg/mL added in equine semen cooling and freezing extenders. Samples were evaluated for sperm kinetics patterns, function of sperm structures and lipid peroxidation. In the experiment, the concentration of 15 µg/mL showed higher total and progressive motility when comparing to control (60.3±3 and 40.7±3.4 vs. 54.9±4 e 35.0±4.4, respectively, P < .05) at M24 of cooling; The concentration of 2 µg/mL showed higher percentage of intact plasma and acrosomal membrane when comparing to control at M24 (51.1±3.6 vs. 46.1±3.9, P < .05), M24 after 30 minutes of incubation (43.4±3.1 versus 32.4±2.6, P <.05). The concentration of 2 µg/mL showed higher percentage of intact plasma and acrosomal membrane (P <.05) comparing to control at moments M0 (43.5±5.0 vs. 36.3±3.5), M30 (41.0±3,7 vs. 35.3±2,9) e M60 (39.0±7.0 vs. 31.4±5.4). Thus, it can be concluded that low doses of ozone can lead to a positive response in the sperm kinetics patterns and sperm structures after sperm storage at low temperatures. Higher concentrations (30 and 60 µg/mL) were harmful in the cooling and cryopreservation of equine semen.

Keywords: Lipid peroxidation; Spermatozoa; stallion.