Temperature and the growth of broilers

Abstract

SummaryLinear and non-linear regression equations were fitted to the data obtained from 17 published papers and one unpublished report. The growth, food intake, food conversion ratio and body composition of the birds kept at different temperatures was expressed as a percentage of the performance of the broilers kept at 21°C. Over the whole range of the data examined (7.2-37.8°C) the growth and food intake responses of the mixed sex flocks are curvilinear. Within a range of 7.2-21°C there is a linear response with growth and food intake decreasing by 0.12% respectively for each degree rise in environmental temperature. The rate of decline in growth rate is greater in males than females.Total carcass fat and abdominal fat increases by 0.8% and 1.6% respectively with each degree rise in temperature. Carcass moisture declined with increasing temperature but there is no significant effect on carcass protein (expressed as % of liveweight).