Effect of environment conditions on milk production in Mitra cow house

Abstract

The objective of this study was to evaluate the effect of thermal environment on the milk during the year of 2004. The experiment was carried in the free stall of the Center of Studies and Experimentation of the Mitra. For the evaluation of the milk productions were used 9 animals of Holstein Frisian breed. For the environment analysis was used the Index of Temperature and Humidity (THI). The data analysis was carried through by ANOVA and using itself the Tukey means comparisons test. The THI values observed in June, July and August months (with higher air temperatures) were included in dangers class and September in alerts class. The higher THI in these months has significant effect on milk production. The decrease in milk production was related to the heat stress during these months. The THI analysis along the year shows that the summer is the only period leading to stress conditions, with negative effect on milk production.