Effects of cage density and cage position on performance of commercial layer pullets from four genotypes

This study was carried out to determine the effects of genotype, cage density and position on the pullet performance of commercial layer chicks housed in cages. Two thousand 1-day-old chicks of Lohman Brown, Lohman White, Isa Brown and Bowans White genotype were housed at 3 cage densities (105.9, 134.8, 185.3 cm²/bird from day 1 to 4 weeks of age; 211.8, 274.5 and 370.6 cm²/bird at 4 to 16 weeks of age) and 3 cage positions (top, middle and bottom rows of the battery). Brown egg layer genotypes were heavier, more uniform and gained more weight with less feed. White egg layers were more sensitive to the effects of treatment. The pullets at the highest density realized optimal final body weight and uniformity with less feed consumption, excluding one genotype. Although the pullets were heavier and most uniform in weight in the bottom row, the feed conversion rate of these pullets was not favorable. Cage density and cage position treatments produced different responses in the different genotypes. It was concluded that if the layer chicks are housed according to their known responses to cage density and position, pullet welfare improves, resulting in better performance.