Rooster Behavior and Laying Breeder Performance in Natural Mating Cages as a Function of Different Rearing Management

Natural mating colony cages are crucial in poultry breeding, yet breed-specific management requires further investigation. We evaluated the effects of sex ratios, stocking densities, and cohabitation age on Lohmann Pink-shell breeders' performance. A total of 6126 birds were randomly allocated to experimental groups with varying ratios (1:8-1:13), densities (582-748 cm²/bird), and cohabitation ages (120/140 days), each containing six replicates. We monitored male mating frequencies at 50 weeks in 1:8 and 1:10 ratio groups. All 120-day-old groups showed delayed production onset and superior male weight compliance (<i>p</i> < 0.01), with reduced egg breakage and increased healthy chick output (<i>p</i> < 0.01). Lower stocking densities (748/694 cm²/bird) showed lower breakage rate and uniformity than 582 cm²/bird (<i>p</i> < 0.05). The 1:10 sex ratio achieved optimal egg production and fertilization rate (<i>p</i> < 0.05). Male mating peaked between 16:00 and 18:00. Optimal parameters were 120-day age of cohabitation, 694 cm²/bird density, and 1:10 sex ratio, providing theoretical guidance for natural mating colony cage development in layer breeding.