Effect of age, stocking density, genotype, and cage tier on feather score of layer pure lines

Abstract

19 The objective of the study was to investigate the effect of genotype, age, stocking density, 20 and cage tier on the feather score of egg-laying pure lines. The trial was carried out with five 21 white (BLACK, BLUE, MARON, BROWN, and D229) and six brown (RIR1, RIR2, BAR1, 22 BAR2, COL, and LINE54) eggshell lines as classified by the Ankara poultry research 23 institute. In the experiment, 162 chicks were randomly selected from each of the 11 lines 24 thus, a total of 1782 chicks (810 and 972 white and brown layer pure lines respectively). At 25 17 weeks of age, pullets were chosen at random and placed in 3tiered battery type cages. 26 Each tier housed 99 chickens (11 lines; 3 different stocking densities; 3 replications). The 27 stocking density was either 5 birds, 6 birds, and 7 birds per cage cell that corresponded to 720 28