Abstract:
The freezability of semen collected during the low (May-July) and the peak (September-November) breeding seasons from 18 Nili-Ravi buffalo bulls of young (3-4 years), adult (6-8 years) and old ( 12- 15 years) age groups was studied. After extension in lactose.:..fructose-egg-yolk-glycerol extender, semen samples were frozen and stored in liquid nitrogen. Post-thaw motili�y and liveability of spermatozoa were higher (p < 0.05) in adult than in young and old bulls and during the peak than the low breeding season. Sperm abnormalities in frozen-thawed semen fr<)m hulls of young, adult and old groups differed significantly (p < 0.05), and were higher (p < 0.05) during the low than the peak bretX!ing season. GOT and GPT activities in fresh, diluted and frozen-thawed seminal plasma from young and old bulls were higher (P < 0.05) than that of adults. GOT and GPT activities in seminal plasma of fresh, diluted and frozen-thawed semen were higher (p < 0.05) in the low than the peak breeding season. Due to freezing, GOT activity in seminal plasma of young, adult and old bulls increased by 29. 80, 2 1. 12 and 38. 15%, respectively. The corresponding values for GPT activity were 16.22, 16.33 and 40.74%. It was concluded that the semen freezability was better in adult buffalo bulls than young or old hulls, ami during the peak than the low breeding season.