Stress preconditioning of rooster semen before cryopreservation improves fertility potential of thawed sperm

ABSTRACT Avian semen cryopreservation is not as successful as that seen in mammals. This failure is mostly attributed to unique physiological characteristics of poultry semen that make it susceptible to cryo-damages. Utilization of sublethal oxidative stress for preconditioning of sperm, as an innovative approach, improves the cryo-survival of sperm in certain mammalian species. The purpose of this study was to investigate the effects of preconditioning of rooster semen with sublethal oxidative stress [very low concentrations of nitric oxide (NO)] before cryopreservation on the quality and fertility potential of thawed sperm. Semen samples were collected from 20 roosters, twice a wk, and different concentrations of NO [0 (NO-0), 0.01 (NO-0.01), 0.1 (NO-0.1), 1 (NO-1), 10 (NO-10), and 100 μM (NO-100)] were used to investigate the effects of controlled induction of sublethal stress before semen cryopreservation on the thawed sperm performance. A significantly higher (P 0.05) affected by different concentrations of NO. Sperm exposed to NO-1 produced the highest percentage of viable spermatozoa (Annexin−/PI−), which was significantly different from the other samples. Finally, rate of fertility after artificial insemination was significantly higher (P