Biochemical appraisal of a milk diluent for semen

Abstract

1. A study was made of the effects of a milk diluent on bull, ram and boar spermatozoa. Respiration and fructolysis of spermatozoa were used as the two main criteria of sperm activity. The milk diluent was a standardized and commercially available milk product, consisting of sterilized and homogenized milk, supplemented with milk fat.2. The rate of oxygen uptake measured manometrically in the presence of air was increased by the addition of the milk diluent throughout the entire incubation period. Fructose utilization was assessed by the rate of lactic-acid production. The rate of the anaerobic lactic-acid formation was higher in the presence of the milk diluent during the later stages of incubation.3. The effect of the milk diluent on sperm respiration was most striking in experiments with the sperm-rich portion of boar ejaculate obtained by fractionated collection. A somewhat less marked effect was observed with bull semen, and in ram semen the effect was comparatively weak.