The Effect of Temperature on the Survival In Vitro of Rabbit Spermatozoa Obtained from the Vas Deferens

Abstract

1. A technique is described for the investigation of in vitro problems with spermatozoa removed from the vas deferens of the rabbit. The method involves the protection of the spermatozoa by means of liquid paraffin from evaporation of rapid gaseous exchange. 2. The survival of functional integrity (fertilizing capacity) has been shown to be a function of temperature and the effect of temperature has been studied over the range from 45° C. to 0° C. Above body temperature the spermatozoa are rapidly destroyed. At body temperature (40° C.) maximal survival is about 13 hours. As the temperature is lowered survival becomes increasingly prolonged until a maximum of 7 days is reached at 15°C. The curve over the range from 15° C. to 40° C. is only approximately exponential and it is doubtful whether an analogy can be drawn between the effect of temperature on the velocity with which the spermatozoa are destroyed, and the effect of temperature on the velocity of many biological reactions which follow approximately the van't Hoff and Arrhenius questions. Below the optimum temperature (10°-15°C.) the velocity of destruction is acclerated by fall of temperature. 3. The sex-ratio of the resulting offspring is not significantly altered by keeping the spermatozoa outside the body.