Efeito do estresse térmico na produção de vacas leiteiras

Abstract

About two thirds of the national territory is located in the tropical zone of the planet, where high temperature and solar radiation predominates, being able to surpass the zone of comfort of the animals, leading to the thermal stress, and consequently affecting the production and the quality of the milk, mainly in cows because they are more sensitive to heat and have greater difficulty in dissipating it. Thus, the objective of this review was to address the main impacts related to thermal stress in milk production and some factors that can be used to minimize these conditions. To control the effects of thermal stress the producer can make use of some strategies of environmental, nutritional management and cooling system. The use of some methods such as natural and artificial shading, diet with lower caloric increment, and use of systems such as ventilator, sprinkler and evaporative panel may prove to be efficient for animals that are subjected to heat. Thus, it is concluded that thermal stress causes several problems to dairy herds and when identified, we can control their effects and minimize economic losses. Several methods to control the effect of thermal stress have proved to be efficient, but the choice of the appropriate method depends on its cost benefit and the specific characteristics of each property.