EFFECTS OF TEMPERATURE ON THE IMMOBILIZATION AND THE INITIATION OF MOTILITY OF SPERMATOZOA IN THE MALE REPRODUCTIVE-TRACT OF THE DOMESTIC-FOWL, GALLUS-DOMESTICUS

1. 1. The motility of undiluted fowl spermatozoa taken from testis, epididymis and ductus deferens was negligible at 40°C, around the normal avian body temperature. 2. 2. The immobilization was not permanent and motility was restored by decreasing the temperature to 30°C or by suspending in a NaCl/TES buffer with 2mM Ca2+, 2mM HCO-3 or 10% seminal plasma at 40°C. 3. 3. Demembranated spermatozoa taken from testis, epididymis and ductus deferens were also immotile at 40°C. However, these spermatozoa were restored the motility at 30°C except testicular spermatozoa. 4. 4. These results suggest that the capacity of movement of fowl spermatozoa can be readily obtained from testis, but that these spermatozoa are immotile due to temperature-dependent immobilization in the male reproductive tract. 5. 5. Furthermore, it is possible that changes in environmental temperature at ejaculation are one of the important exogenous physiological factors of the initiation of fowl sperm motility. © 1990.