Impact of microclimatic conditions on sperm production in Czech Holstein bulls: A correlational study

<br />In this study, the influence of microclimatic conditions in different seasons of the year (including the hottest months) on the quantitative and qualitative characteristics of ejaculates of Czech Holstein bulls was assessed. Bulls were kept in the facility with no forced ventilation or air conditioning. To determine the influence, the temperature-humidity index (THI) was calculated based on the microclimatic parameters measured directly in the facility with the animals. Bull sperm was obtained using an artificial vagina on five occasions throughout the year, in different seasons of the year including the hottest months. Semen was assessed for its volume, sperm concentration, and motility by CASA, as well as cellular viability by using flow cytometry. In the present study no statistically significant positive correlations between values of THI and sperm degradation were observed. Obtained preliminary results give grounds to believe that Czech Holstein bulls produced high-quality sperm during the summer, the hottest months of the year.