PREDICTION OF FREEZABILITY ON THE BASIS OF SEMINAL PLASMA ENZYMATIC PROFILES IN MURRAH, FRIESIAN AND CROSSBRED BULLS

Six ejaculates collected fortnightly from each of 5 Murrah, 3 Friesian and 5 triple crossbred bulls were studied for the seminal plasma enzymatic profiles of transaminases (GOT-GPT),phosphatases (AKP-ACP) and lactic dehydrogenase (LDH) during hot summer months in relation to their semen freezability. Statistically highly significant (P<0.01) differences were observed between 3 breeds/species for all the parameters studied except GPT activity. The ratio of GOT-GPT and AKP-ACP also varied between them. Similarly, the bulls within the breed varied significantly for their semen freezability and the seminal plasma profiles of all the 5 enzymes. Murrah buffalo had significantly lower GOT, and higher LDH, AKP and ACP than the cow-bulls, yet the freezability was of intermediate grade between HF and crossbred bulls, Among the cow-bulls, freezability and the activity of LDH and GOT was significantly higher in Friesians and AKP-ACP in the crossbred bulls. Bulls donating good to excellent quality semen ejaculates had AKP-ACP and lower values of GOT-GPT and LDH in their seminal plasma. Thus, the variations in the quality and freezability of semen from the bulls of different breeds/species could be explained on the basis of their seminal plasma enzyme activity.