[Addition of methyltestosterone to bull semen. 1. Effect on metabolism of spermatozoa]

Added to bull semen preserved by deep freezing, methyltestosterone at a concentration of greater than or equal to 1 mg per ml diluted semen reduced the respiratory rate, glycolysis, lactate index of spermatozoa and the rate of radiosodium exchange through the spermatozoal membrane. The mode of action is discussed.