HEAT LOSS FROM BROILER CHICKENS SUBJECTED TO VARIOUS AIR SPEEDS AND AMBIENT TEMPERATURES

Abstract

Although the use of tunnel ventilation is expanding, there remains some ambiguity about heat loss experiencedby broiler chickens at air speeds in the range commonly used with tunnel ventilation. A wind tunnel-type habitathousing up to 500 broilers was created and instrumented to measure heat loss from the broilers subjected to a variety ofair speeds and ambient temperatures. Treatments included ambient temperatures of 29, 32, and 35C (85, 90, and 95F)and air speeds of 61 to 183 m/min (200 to 600 ft/min) in 30 m/min (100 ft/min) increments. Results indicate that as airspeed increases, broilers experience increases in sensible heat loss and corresponding decreases in latent heat loss. Thesum of the two (total heat loss) tended to remain constant with increased air speed. A general decrease in sensible heatloss accompanied by a general increase in latent heat loss was observed as temperature was increased.