62 Impact of Feeding Male Goats with L-Carnitine on Viability of Their Semen Stored at 4 °C for 72 Hours

Abstract

Abstract Goats have the ability for genetic improvement. Artificial insemination (AI) is a significant technique used to increase genetic gain. Low fertility in goats with AI was attributed to semen quality, which can be affected by cooling/freezing procedures. Cooling of spermatozoa causes reduction in viability, and loss of fertility, mainly because of oxidative stress. L-carnitine (LC) is important for fatty acid metabolism and acts as antioxidant. Many studies have reported positive impact of LC on quality of cooled spermatozoa in different species; however, no research has been done on goats. Here, we investigated the impacts of dietary supplementation of LC on the quality of cooled goat semen. Six mature Alpine bucks were allocated into two groups; control (three bucks were fed a regular diet without LC supplementation), and treatment (three bucks were fed the normal diet plus 0.022 g/kg of BW, LC). Bucks were fed their respective diet for sixty days from January to March (non-breeding season). Semen was collected once/week and evaluated for color, consistency, volume and sperm concentrations. Diluted semen was then stored at 4 °C for 72 h. Sperm motility, viability, and membrane integrity were assessed at 0, 24, 48, and 72 h post-cooling. Results showed that colors of samples collected from the two groups were white to yellow, consistency ranged from watery to creamy, and sperm concentrations ranged from 8.1 to 12.2 x 109 sperm/ml. Sperm motility, viability and membrane integrity reduced (P≤ 0.05) in a time dependent manner in both groups. At 72 h, motility decreased by one-half as compared with 0 h (48.9% vs. 91.4% and 32.5% vs. 80.8%, in LC and control groups, respectively). In conclusion, under our experimental conditions, goat spermatozoa can be stored at 4°C for 72 h without severe loss in their quality. LC treatment has less impact on the quality of cooled goat semen.