Sperm production of a pony stallion and the treatment of spermatozoa in vitro with special reference to artificial insemination of mares

Abstract

1. The sperm production of a pony stallion kept a constant high level when the collection of sperms was performed regularly three times a week. There was no adverse effect on the stallion or on the quantity and quality of the sperms. There is a negative correlation between the volume of semen and the concentration. The total number ejaculated remains relatively constant; the volume of accessory fluids is more variable.2. The motility of horse spermatozoa after dilution with eight different kinds of chemical media and stored at different temperatures was studied: Glucose-yolk-phosphate dilutor devised by Lamhert & McKenzie and glucose-yolk-tartrate dilutor devised by the author were found to be the best for the preservation of horse sperms at low temperature. There was not much difference between those diluted samples stored for 24 hr. at 10° C. and those slowly cooled to 1° C. Concentration of the semen by centrifuge is definitely beneficial for the preservation of horse sperms.3. Pregnancies were obtained by the insemination of sperms centrifuged and kept at 1° C. for 24 hr. The sperms of one stallion can be used for a great number of mares if artificial insemination is practised. The adoption of new techniques for the determination of the time of ovulation and for the induction of ovulation is suggested for successful artificial insemination of mares.