Effect of Diluent Composition on Survival and Fertility of Bovine Spermatozoa Stored in Carbonated Diluents

Abstract

Tne concentration of each constituent of the carbonated illini variable temperature (IVT) diluent, which utilizes the principle of metabolic inhibition by CO2 and other substances was studied as to the effect on survival and fertility of bovine spermatozoa. The IVT diluent normally contains 0.21 g potassium chloride, 0.30g glucose, 0.30g sulfanilamide, 100,000 IU penicillin, and I00,000[mu]g streptomycin per 100 ml H2O. Carbonation is accomplished by bubbling CO2 through the diluent for 10 min. after which 10% egg yolk is added. Changes in potassium chloride or sulfanilamide concentration had little effect on spermatozoan survival. An increase in glucose concentration to 0.067 M resulted in better sperm livability. Little difference was noted in sperm survival in diluents with 5, 10, or 20% egg yolk during storage at 26.5 C whereas at 5 C, 20% egg yolk permitted longer sperm survival. Tne addition of catalase together with higher levels of egg yolk and glucose, greatly increased survival. When the sodium bicarbonate concentration was increased to 0.10 M in a diluent containing 0.067 M glucose and 15% egg yolk and the storage ampules were flushed with CO2, 47% live sperm were found after 60 days of storage at 5 C. This diluent also resulted in an increase in fertilizing capacity during one week of storage as compared to the fertility of semen in the unmodified diluent.