Fertility of Bull Sperm with Added Catalase

Semen, from 44 bulls, that had been extended in glycerinated milk or Cornell University Extender (CUE), each with and without 1 7/ml of added eatalase, was used to inseminate 23,837 first-service cows, to measure the effects of catalase on fertility during storage for four days. CUE resulted in averages of 77.5, 74.8, 68.3, and 69.5% 60-to 90-day nonreturns for Days 1, 2, 3, and 4 of storage, respectively. The comparable averages for glycerinated milk were 73.9, 70.1, 65.9, and 56.2; for CUE with catalase were 78.2, 74.0, 69.8, and 68.1; and for glycerinated milk with catalase were 74.2, 74.9, 69.4, and 61.0.