64 Effects of L-Carnitine Dietary Supplementation on the Quality of Buck Semen Collected During non-Breeding Season

Abstract

Abstract Artificial insemination (AI) has potential impact on goat breeding. Reduced fertility in goats following AI is mostly associated with semen quality, which is influenced by breed, collection methods, freezing procedures, and the male diet. L-carnitine (LC) plays an integral role in sperm metabolism by supplying energy through β-oxidation to enhance sperm motility. L-carnitine is also important for fatty acid metabolism and acts as an antioxidant. Positive impact of dietary supplementation with LC on sperm quality and fertility has been reported in many species; however, no studies have been conducted on goats. The objective was to evaluate the effects of dietary supplementation of LC on the quality of goat semen collected by electroejaculation during non-breeding season. Six mature Alpine bucks were randomly assigned into two groups, namely control (three bucks were fed a regular diet without LC supplementation), and treatment (three bucks were fed the normal diet plus 0.0022 g/kg of BW, LC). Each feeding trial last for 60 days from January to March (the non-breeding season). Semen was collected from the bucks once/week by electroejaculation and evaluated for its physical characters. Sperm motility, concentrations, viability, membrane integrity, and abnormalities were also examined. Results showed that colors of the samples collected from the two groups were white to yellow and the consistency ranged from watery to creamy. Percentage of live spermatozoa (69.7%) was greater (P≤ 0.05) in LC group than control (50.1%). However, no significant differences (P > 0.05) were observed in semen volume, sperm concentration, motility, abnormalities, and membrane integrity between the two groups. In conclusion, supplementing bucks LC during non-breeding season enhanced sperm viability. Further experiments are in progress to evaluate the effects of LC on reproductive variables and the levels of reproductive hormones such as testosterone, FSH, and LH in the blood of male goats.