Aim: The present study was conducted to evaluate the quality of rooster sperm at 5°C after treatment with a diluent containing coconut water, fructose, and chicken egg yolk and stored the semen sample at 5°C.

Materials and Methods: Ten semen samples from 10 healthy roosters were subjected to four different treatments. For the treatments, 0.2 ml fresh semen with a sperm concentration of 5.2X10⁹ cell/ml was mixed with T0 (no diluent), T1 (0.34 ml coconut water and 6 μl fructose), T2 (0.274 ml coconut water, 0.12 ml egg yolk, and 6 μl fructose), and T3 (0.34 ml egg yolk and 6 μl fructose) solutions. Each treated solution was stored at 5°C and evaluated both macroscopically and microscopically. Macroscopically, semen volume, pH, and sperm concentration were evaluated. The microscopic sperm characteristics examined included total motility (i.e., rapid, medium, or slow), progressive and non-progressive motility, viability, and spermatozoa abnormalities noted at different storage times. The results showed that spermatozoa motility was under 40%.

Results: The results indicated that sperm viability significantly affected (p<0.05). The highest mean value of sperm viability on day 7 of storage was found after treatment with the T2 solution (46.100±0.5677%). Similarly, spermatozoa abnormalities were significantly lower after treatment with the T2 solution (6.680±1.702%).

Conclusion: The addition of a diluent containing coconut water, egg yolk, and fructose helped in the better preservation spermatozoa motility, as well as viability for up to 7 days when the semen samples were stored at 5°C.

Keywords: chicken, coconut water, diluent, egg yolk, sperm quality.