ADAPTATION OF BROILER CHICKEN BREEDERS TO COLONY CAGE ENVIRONMENTS

Abstract

Dwarf and non-dwarf broiler breeders were compared for adaptability to colony cages in terms of productive and reproductive performance. Generally, the results indicated that the dwarfs possess a better adaptability to colony cages than the non-dwarfs. This study also demonstrated that a significant difference in fertility existed among pairs of males performing natural matings in cages. Such a result suggests that depending on the heritability of the trait, specific strains of males could possibly be developed through selection practice to improve the decreased fertility resulting from the use of colony cages, where this would be accomplished through the development of genotypes to perform in cages. The interaction between genotype (non-dwarf vs. dwarf) and environment (pen vs. cage) was found to be highly significant for egg production and feed conversion. The dwarfs were inferior to the non-dwarfs in the pens by 7.6% in hen-day egg production but superior to the non-dwarfs in the cages by 3.2%.