Dependence of physical characteristics of ejaculate of Polish Landrace boars on the time interval between successive ejaculate collections

Abstract

The aim of the research was to determine the dependence of physical properties of boar ejaculates on the time interval between successive ejaculate collections. The material for the study comprised 1954 ejaculates collected manually from boars used for artificial insemination. For all ejaculates, the ejaculate volume, sperm concentration, percentage of motile spermatozoa, and number of spermatozoa in the ejaculate were determined, and the number of insemination doses per ejaculate was calculated. The boars’ suitability for artificial insemination was evaluated taking into account the effect of the time passed between ejaculate collections. The ejaculate volume and the concentration and number of sperm in the ejaculate were shown to increase with the time elapsed since the previous ejaculate. The number of insemination doses obtained per ejaculate increased as well. Ejaculates with a high sperm count were obtained when the ejaculation frequency was no more than every 4 days. The percentage of spermatozoa with progressive motility increased with the time elapsed since the collection of the previous ejaculate, but only up to 4 days. Further decreases in ejaculation frequency no longer resulted in increased sperm motility.