The Activity of Ram Spermatozoa

Abstract

1. Concentrated suspensions of active ram spermatozoa exhibit periodic changes in their electrical properties when these are measured in an a.c. bridge. 2. Suspensions containing immobile or feebly active spermatozoa do not exhibit this phenomenon. 3. The frequency of the changes has the following characteristics: (a) It is maximal when the suspension is fresh, and declines to zero after some 60 min. at 37° C. (b) It can be maintained for about 20 min. at a high level by the addition of phosphate buffer. (c) It is susceptible to changes in temperature, the Q10 between 16 and 36° C. being about 2. 4. A tentative hypothesis is put forward that these electrical changes are caused by the spontaneous, reversible aggregation, or ‘turbulent wave formation’, which is characteristic of active and concentrated suspensions of ram spermatozoa; and that they are due to the position of the spermatozoa in the measuring apparatus rather than to any intrinsic changes in the electrical properties of individual spermatozoa. 5. As the frequency and intensity of the wave formations are thought to be proportional to sperm motility, there is a possibility that the electrical changes might be used as an objective and physical measure of sperm motility. 6. Certain advantages and disadvantages in measuring the activity of the sperm suspensions by this method are discussed.