Efficiency of effect of high ambient temperatures on food utilisation in male broilers

The effect of ambient temperatures above 28 degrees C on the efficiency of food utilisation were studied in 7 consecutive flocks of male broilers, grown in a cross-ventilated controlled environment poultry house. The best correlation between the food:gain ratio and temperature was obtained when the latter was expressed as degrees-h (Th), that is, the aggregate of the differences between the ambient temperature and 28 degrees C, measured hourly. The equation: Food:gain ratio = 2072 + 0.125 X Th, demonstrates clearly the negative effect of high temperatures on food:gain ratio in broilers. It might be helpful for the broiler industry when evaluating the need for and planning of cooling devices for poultry houses.