Membrane integrity, mitochondrial activity, ATP content, and motility of the European catfish (Silurus glanis) testicular spermatozoa after freezing with different cryoprotectants

The extent of cellular damage was investigated after freeze-thawing of the European catfish testicular sperm with various cryoprotectants. The best pr otection was given by dimethylacetamide (10 and 15%) in a sucrose solution. Under these conditions, the percentage of cells with an intact membrane wa s high (90%), and the protection of the activity of the mitochondria was me dium (47%). It was shown that the addition of dimethylacetamide largely inc reased the ATP content of the spermatozoa. It is suggested that this phenom enon is a decisive factor for the freezing resistance of European catfish t esticular spermatozoa in the presence of dimethylacetamide (60% motility af ter thawing versus 90% before freezing). (C) 1999 Academic Press.