Effect of different cooling systems on lying time of dairy cows in cubicles with separated manure solids bedding / Vplyv rozdielnych systemov ochladzovania na dobu lezania dojnic ustajnenych v leziskovych boxoch podstielanych separovanym kalom hnojovice

The aim of this study was to investigate the changes of lying time and other behaviour manifestations of dairy cows during usage of different cooling systems of animals. Alternative hypothesis was presumption, that the lying time of cows in lying cubicles with applied two different cooling systems are indifferent. The sprinkling system was used to animal cooling in group S in summer time. In group SV was disposable sprinkling system and diagonally rotated ventilators. Activities and the rest of animals were evaluated in 10 minute intervals using a camera system for 24 hours. Data obtained was tested by nonparametric Kruskal-Wallis one-way ANOVA and multiple comparison test for detecting of significant differences in the behaviors between groups of cows. There was found positive effect of animal enhanced cooling using sprinkling system with increased air movement by ventilators. It reflected in significant prolongation of whole lying time and shortening of time, when animals were standing. It resulted from final values of investigated behaviour manifestations of dairy cattle within 24 hour period that animals in group SV with sprinklers and ventilators lay in stalls longer than in group S with sprinklers, but without ventilators (10.76 h*[d.sup.-1]*[cow.sup.-1] vs. 7.71 h*[d.sup.-1]*[cow.sup.-1], P