Effect of different extender formulations on acrosomal maintenance of buffalo spermatozoa frozen in milk, tris and sodium citrate dilutors
Kumar, S.; Sahni, K.L.; Mohan, G.
Indian Journal of Animal Sciences 63(12): 1233-1239
1993
ISSN/ISBN: 0367-8318 Accession: 009827546
Percent normal acrosome (PNA) decreased significantly in citrate dilutors when compared to milk and tris, both at prefreeze and post-thaw level. Maximum damage to acrosome was recorded after pre-freeze stage (at chilling temperature). Almost all the types of abnormalities increased during freezing but most of the abnormalities were of swollen and ruffled type. Minimum loss to PNA at prefreeze level was found in milk dilutor containing 6% glycerol, 5% yolk and 1% fructose, whereas citrate buffer containing 9% glycerol, 5% yolk and 2% raffinose resulted maximum loss to PNA. After freeze thawing maximum loss to PNA was recorded in citrate containing 6% glycerol, 5% yolk and 1% sucrose, and minimum in tris control containing 7% glycerol, 5% yolk and 1% sugar (common table sugar containing 99.8% sucrose). Addition of fructose in milk reduced the loss in PNA. But other carbohydrates did not impart this effect. Addition of more than 1 carbohydrate was harmful. A definite role of type and level of carbohydrates, and level of yolk and glycerol as cryoprotectant in the extender formulation was observed. Higher yolk and glycerol level were not beneficial in maintenance of normal acrosome during freezing.