This study was carried out to investigate the effect of addition of different levels of L-arginine (0, 3, 5, 7 and 10 mM) to improve the poor motile of Holstein bulls spermatozoa. Semen collected from five Holstein bulls once weekly and ejaculates with 45-50% mass motility was pooled. Semen was diluted with Tris- egg yolk extender at 37C° and divided into five parts,1st part without supplement (control), other four parts 2nd , 3rd , 4th and 5th were supplemented with 3, 5, 7 and 10 mM L-arginine respectively. Diluted semen was equilibrated at 4 C° for 4 h, then, filled in 0.25 ml French straws. Straws were kept on liquid nitrogen vapors for 10 min and then plunged and stored in liquid nitrogen at -196C°. Progressive sperm motility, live sperm, abnormal sperm and sperm acrosome integrity were determined post-dilution, equilibration and post-thawing processing.
The results were referred that extenders with concentrations of 5 and 7mM L-Arginine were improved all parameters studied than 3; 10 mM L-arginine extenders and control extender at different cryopreservation processes. The percentage of DNA damage were 20.0, 10.8, 4.40, 3.20 and 9.40 for control and 3, 5, 7 and 10 mM L-arginine extenders respectively. Significant differences in chromatin integrity were observed among control and treatments (P
Conclusively, it could be concluded that adding L-arginine with concentrations of 5 or 7mM to Tris-extender improved the freezability and fertility of poor quality of Holstein bull spermatozoa.