[Relations of certain indicators of ejaculate quality of breeding boars to seasonal changes in the microclimate in pigsties].

A yearlong evaluation of the semen volume, concentration and number of morphologically abnormal sperms of 1722 ejaculates from 53 boars of Large White, Duroc and Landrace breeds housed in one building was performed. Simultaneously, continuous registration of temperature and of the relative humidity of the sty climate was performed, and the cooling value and the air flow in the sty were determined. In the followed period also the conception rate of sows after the first insemination by semen of the studied set of boars was evaluated. In summer season, at the increased and high temperatures and the relative sty humidity and at the lower air flow, the lowest average volume of ejaculate, the highest average sperm concentration and the minimum average number of abnormal sperms were recorded. In winter season, from the microclimatic viewpoint characterized mainly by the optimum air temperature but by high relative humidity and by excessive air flow, the highest average ejaculate volume with a lower average sperm concentration and with a maximum occurrence of abnormal sperms was recorded. The parametric differences in ejaculate quality in summer and winter seasons were statistically significant, however, their variations did not exceed the spermiologic standard throughout the year. The found decrease in conception rate of sows after the first insemination by the semen of the followed set of breeding boars in warm months is obviously to be attributed to the sows or to the changes of other andrological criteria than those being subject of this study.