THE EFFECT OF COLLECTION SEASONS ON THE SEMEN QUALITY OF HOLSTEIN-FRIESIAN BULLS

Abstract

The study, which included 9 Holstein-Friesian bulls from the Livestock Center of the PKB Corporation, analyzed the impact of the ejaculate collection season on certain semen properties (ejaculate volume, sperm concentration, sperm motility in native ejaculate, sperm dilution, number of doses of one ejaculate and mobility of spermatozoa after thawing). For the purposes of this analysis, data for the three-year (2011-2013) and one-year period (2014) were used. In the three-year period, based on 621 ejaculates of three bulls, the average values for examined properties were calculated and the season's impact on these properties analyzed. The results show that the ejaculate collection season had a very significant effect (p<0.001) on the sperm motility in native ejaculate, and a significant effect (p<0.05) on the level of dilution of ejaculate and the mobility of spermatozoa after thawing. In the single-year period, based on 326 ejaculates from 9 bulls, the average values of the studied properties were calculated, and the influence of the season was also analyzed. The ejaculate collecting season showed a very high impact (p<0.001) on the mobility of spermatozoa after thawing, but no significant effect was found on other properties (p> 0.05).