ENZYME LEAKAGE DURING CRYOPRESERVATION OF RAM SPERMATOZOA

Spermatozoal motility and enzyme leakage during cryopreservation of ra m spermatozoa was evaluated in the presence and absence of antifreeze proteins (AFP). Loss of spermatozoal motility due to the cryopreservat ion process was reduced by 10% in the presence of AFP. Samples of the diluted semen at various stages of the cryopreservation process were a ssayed for aspartate transaminase (AST), alanine transaminase (ALT), a lkaline phosphatase (ALP), acid phosphatase (ACP) and lactate dehydrog enase (LDH). The levels of AST, ALT and ACP were low in ram spermatozo a and were not considered suitable for the objective measurement of sp ermatozoal damage. ALP leaked during the cooling and freezing process, whereas LDH leakage was prevalent during cooling, freezing and post-t haw incubation of spermatozoa. Changes in ALP and LDH could be used as marker enzymes in the development of semen processing protocols and o f semen diluents.