Increasing sperm production and improving cryosurvival of semen in aged Thai native roosters as affected by selenium supplementation.

OBJECTIVE

Aging roosters typically exhibit subfertility with decreasing semen quality, furthermore Thai native roosters reared in rural areas are raised for a longer duration than their usual lifespan. The present study therefore aimed to assess the effect of selenium supplementation as an antioxidative substance in diets to improve the semen cryopreservation of aged roosters.

METHODS

Semen samples were collected from young (n = 20) and aged (n = 20) Thai native roosters (Pradu Hang Dum) at 36 and 105 weeks of age when starting the experiment, respectively. They were fed diets either non-supplemented or supplemented with selenium (0.75 ppm). Fresh semen quality and lipid peroxidation of fresh semen was evaluated before cryopreservation using the traditional liquid nitrogen vapor method. Post-thaw sperm quality and fertility potential were determined.

RESULTS

Advancing age is unrelated to decreasing fresh semen quality (p>0.05). However, lipid peroxidation in rooster semen depended on age, and the malondialdehyde (MDA) concentration increased in aged roosters (p<0.05). Selenium supplementation in diets significantly decreased the MDA concentration and increased the sperm concentration (p<0.05). In contrast, cryopreserved semen was affected by advancing rooster age, and selenium influenced sperm quality (p<0.05). Younger roosters had higher post-thaw sperm quality and fertility potential than aged roosters (p<0.05). Likewise, diet selenium supplements improved post-thaw sperm quality and fertility compared with the non-supplement group.

CONCLUSION

Rooster's age does not influence the rooster sperm quality of fresh semen, while sperm cryotolerance and fertility were greater in young roosters than in aged roosters. However, sperm of aged roosters could be improved by dietary selenium supplementation.