Motility and Fertility of Spermatozoa as Affected by Increased Ambient Temperature

Exposing male rabbits to a temperature of 110° F. at a relative humidity of 30 to 40 percent for one hour did not affect the motility of spermatozoa in most cases. Fertility tests were made in six different trials, each including semen from one heat-treated rabbit and from one control. The treated rabbits exhibited no decrease in percentage of spermatozoa showing forward movement for one month after treatment. The effect of heating on the ratio of fertilized to unfertilized ova in test females was significant with some recovery by 21 to 30 days after treatment. It is concluded that increased ambient temperature may affect male fertility without bringing about any apparent depression of sperm motility.