LAUSR

The study was conducted to investigate the effect of L-Carnitine supplementation in Tris - egg yolk (TEY) diluents to optimize the quality of P asundan bull liquid semen. S emen samples were collected from three P asundan bull s (6 – 7 years old) using an artificial vagina. Semen samples were evaluated macroscopically and microscopically , semen having ≥70% progressive motility, ≥500×10 6 ml -1 sperm concentration and ≤ 20% sperm abnormalities were divided into 5 equal part. Each part was diluted with TEY and supplemented with 0 mM (control), 1 mM, 2 mM, 3 mM and 4 mM L-Carnitine. Liquid semen was stored at 5 °C. Sperm motility was evaluated every 12 h objectively using Computer Asissted Sperm Analysis (CASA ) until progressive motility reached 40%. The best diluent was demonstrated by progressive motility (PM) by TEY supplemented with 1 mM L-Carnitine (43.08±0.49 % ) that remained up to 108 h compared to the control group (43.63±0.70 % ) that remained up to 72 h (P<0 . 05). In conclusion, 1 mM L-Carnitine in TEY was the best concentration for  preservation of P asundan bull semen stored in the liquid form.