Cryopreservation and fertility trials of Clarias batrachus spermatozoa

Abstract

A protocol of cryopreservation for the spermatozoa of Asian catfish Clarias batrachus based on chemical and biochemical parameters was developed. Tris and BWW buffers were used in combination with 3 cryoprotectants (dimethyl sulphoxide, glycerol and methanol) in different concentrations. The egg yolk was used as a part of extending medium. Among the 2 extenders tried, tris gave better results (89.30% motility). The fertilization percentage ranged between 5-20% with tris-glycerol (8%) providing 20% fertilization. The chemical analysis oftesticular tissue showed the concentrations of different elements as sodium 853.60±0.75 ppm, potassium 329.00±0.51 ppm, calcium 59.95±0.23 ppm, magnesium 30.25±0.07 ppm and zinc 9.74±O.07 ppm. The concentrations ofglucose, ascorbic acid, LDH and MDH was 55.92±1.07 mg/g, 39.85±0.42 I-tg/g of testicular tissue, 312.30±5.28 unit/mg protein/min and 196.18±2.97 unit/mg protein/min respectively.