INTERACTION OF STRAIN, DENSITY AND RATION WITH TWO LIGHT SYSTEMS ON BROILER PERFORMANCE

Abstract

Two experiments were conducted to determine the effect of continuous and intermittent (1 hr on and 3 hr off) light treatments and the influence of strain, density and ration on performance of broilers maintained on each light treatment. Three thousand and six hundred broilers of two strains were grown with 0.093 m 2 and 0.047 m 2 of floor space per bird in experiment 1. Three thousand broilers from one strain were grown with 0.093 m 2 of floor space per bird in experiment 2; 600 birds were fed each of five test rations. Body weight, mortality and feed efficiency were calculated in both experiments and slaughter grade was determined in experiment 1. Birds grown on intermittent light had lower mortality and better feed efficiency than those on continuous light. Average body weight at 7 weeks of age was not significantly different for the two light treatments; however, significant interactions were observed for strain × light, density × light and ration × light. Light treatments did not affect the percentage of grade A carcasses at slaughter. Strain and ration had a significant effect on 7-week body weight, as did bird density, in that birds maintained at 0.093 m 2 were heavier and had a higher percentage of grade A carcasses than birds at 0.047 m 2 .