Bovine Semen Metabolism. II. Influence of Sperm Concentration and Initial Fructose Level on Fructolytic Activity

Abstract

A multiple regression study of 70 semen samples showed that both sperm concentration and initial fructose level of semen samples influenced the amount of fructose utilized by bovine spermatozoa. A highly significant multiple correlation (R = 0.63) was found on an ejaculate-in-bull basis between them and fructose utilization in 60 minutes. The addition of fructose to semen in a 30-sample split-ejaculate study, so that the mean initial fructose level was increased from 3.94 to 7.19 mm/ml, resulted in an increase in 60-minute utilization from 2.00 to 3.23 mg. In neither study did the sperm concentration or the initial fructose level have any effect on the fructolysis coefficient (Ku), which is a measure of rate of fructolysis based on first-order rate principles. Adjustment by regression formula for the influence of both sperm concentration and initial fructose level on fructose utilization was proposed. Application of this formula to 60-minute utilization data in the fructose addition study resulted in the adjustment of the fructose and control means to equal fructose utilizations. It is suggested that the fructolysis coefficient and the adjusted fructose utilization are 2 measures of fructolysis which may be useful in the comparison of semen sample quality, and in the detection of factors, other than sperm concentration and fructose level, which influence fructolysis.