The thermal environment inside of a finishing phase swine barn has great influence on the success of swine production. This environment can be characterized by the black globe temperature and humidity index (BGHI), that represents the air temperature, humidity, wind speed and radiation. Due to the small number of Brazilian reports on this specific subject, this experiment was performed to verify the effect of one kind of evaporative cooling system on the thermal comfort of the animal in a swine barn, during the 98/99 summer at Patos de Minas, MG, Brazil. Two constructions were used, divided in 36 barns, each one with 15 animals, 110 to 150 days old. Along a side of one barn, four cooling devices were installed, with a ventilation system connected to a sprayer, to form an evaporative cooling system (ECS). The other barn did not have any cooling system being a control unity (COS). The ECS provided an improvement of the environmental thermal conditions, reducing the index of black globe temperature and humidity inside the building, from 83.5 to 82.4, during the critical period of the day (2 p.m.). The ECS provided also an improvement of the food conversion, from 3.27 to 2.88, and a tendency of a substantial weight gain, from 0.97 to 1.02 kg per day.
ventilation; thermal environment; thermal comfort
