evaluating the effects of guanidinoacetic acid supplement on rooster spermatozoa freezability

the aim of the current study was to evaluate the effects of the guanidinoacetic acid (gaa) supplement on the semen freezability of broiler breeder roosters. experiments were performed with twenty ross commercial strain broiler breeder roosters in four treatments and five repeats in a complete randomized design. roosters were fed a diet containing 0% (control), 0.06%, 0.12% and 0.18% gaa supplement for eight weeks. semen samples were collected weekly by abdominal massage. in order to equilibrate the temperature, semen samples were diluted with an extender and placed inside the refrigerator at 5 ° c. samples were then packed into straws, exposed to nitrogen vapor and finally moved into liquid nitrogen containers. after freezing-thawing, the total and progressive motility, viability, morphology and membrane integrity of spermatozoa were assessed. the mean of total motility at the 0.12% and 0.18% levels were significantly higher than that of other groups (p