EFFECT OF HEAT STRESS ON BEHAVIOUR AND PRODUCTIVITY OF DAIRY COW

Abstract

Due to the effects of heat stress, the dairy industry in tropical countries must deal with a number of difficulties. This study presents a novel method for examining the behavioural symptoms of heat stress, including panting, increased respiratory rate, and restlessness. The majority of the cows under study also exhibited other symptoms like refusal to eat and refusal to lie down. The temperature humidity index (THI) is another important indication that was taken into consideration for this investigation. In this study, 150 cross-bred cows were used, and the majority of them displayed behavioural symptoms and decreased milk output as a result of heat stress. The THI level was over the comfort level of 15 farms. The maximum THI index was over 80 and no farms environment were below the THI threshold level, which only points to a hot environment and poor farm management practices. The majority of the cows also had higher rectal temperatures. Currently, heat alleviation techniques include air movement (fans), wetting (soaking) the cow's body surface, high-pressure mist (evaporation) to cool the air in the cows' habitat, and structures made to reduce solar radiation transfer. Finally, producers may now optimize the positive impacts of photoperiod length while reducing negative effects because of a greater understanding of how photoperiod affects cattle.