Morphological changes in chicken and turkey spermatozoa incubated under various conditions

The viability and morphology of undiluted and diluted chicken and turkey spermatozoa were compared when incubated at either 41, 25, 15, or 5 C for 0 (control), 3, or 6 hr. Increasing the incubation time to 6 hr, raising the incubation temperature to 41 C, or both resulted in higher numbers of dead spermatozoa in semen from both species. Conversely, dilution (1:5 with Beltsville Poultry Semen Extender) of chicken or turkey semen resulted in a significant (P less than .05) decrease in the number of dead spermatozoa as compared to their respective undiluted counterparts, especially in samples incubated at 41 C. Turkey semen exhibited a somewhat lower percentage of dead spermatozoa, bent spermatozoa, and sperm tail coiling than did chicken semen incubated under similar conditions. No significant (P greater than .05) differences were observed in chicken and turkey semen samples when measuring other sperm cell abnormalities regardless of incubation conditions. These results indicate selective species differences in sperm morphological changes in response to incubation temperature, incubation time, and semen dilution.