Broiler production under varying population densities

The influence of population density on the growth performance and stress level of Hubbard x Hubbard chicks of equally mixed sex was studied. Six hundred and sixteen birds were housed under .05, .07, .09, or .11 m2 per bird (four replicates per density) from 0 to 7 wk. There were no treatment effects on feed conversion at 6 or 7 wk. Birds housed at .07, .09, and .11 m2 per bird had similar 7-wk BW and carcass weights, all significantly higher than birds housed at .05 m2 per bird. Under .05 m2 per bird, a higher percentage of breast blisters and ammonia burns (30%) was observed than at other densities. The 7-wk heterophil to lymphocyte ratios of birds raised at .09 and .11 m2 per bird (.42 and .45) were significantly higher than those at .05 and .07 m2 per bird (.28 and .30). Lowered BW and decreased carcass quality of birds raised at .05 m2 per bird suggested that these birds were stressed. However, decision analysis of economic potential indicated that the optimum profit potential per square meter was .05 m2 per bird for Maximax and Equally Likely decisions and .07 m2 per bird for the Maximin decision.