A heat balance model for cattle in tropical environments

[摘要] - An equation based on heat transfer theory was presented to estimate the rate of heat loss from cattle exposed to a tropical environment, specified by the air temperature, humidity, solar radiation, and wind speed. The animals' variables (sweating rate, rectal temperature, respiratory rate, surface temperature, haircoat color, and body weight) were considered together with environmental variables (air temperature and humidity, solar radiation, wind speed, and globe temperature). The equation allows the prediction of (a) the metabolic heat production level necessary to balance heat losses under specified environmental conditions; (b) the combination of environmental factors that provide a determined heat flux between a given animal and its environment.

[学科分类] 兽医学

[关键词] cattle;model;thermoregulation     IntroduçãoExiste crescente interesse em modelos que descrevem a termorregulação de animais domésticos;visando sobretudo a previsão ou estimação das reações dos mesmos em ambientes específicos