The long-term productivity of hens housed in battery cages and an aviary

This study examined the long-term effects of housing system on several aspects of laying hen production. At 19 wks of age, 336 White Leghorn hens were placed, 3 birds per cage, into battery cages; 437 birds were assigned to an aviary with communal nests, ambulation areas, and three raised tiers with feeders and drinkers. Family groups were split between the two housing systems. The hens were housed in such a manner for over 3 yr (until the end of the 168th wk of age), with forced molts between 66 and 74 and between 119 and 125 wk of age. Feed consumption and conversion, egg weight, eggshell deformation, and hen-day productivity were assessed monthly in both systems. Although feed consumption and conversion tended to be higher in the aviary throughout the study, these variables differed significantly due to housing system only in Year 2 (P = 0.04). There were no differences in egg weight (P = 0.7), eggshell deformation (P = 0.85), egg cracking during shaking (P = 0.34), total hen-day productivity (P = 0.55), or egg mass produced per hen per month (P = 0.4). Although aviary systems have been criticized for egg losses due to floor laying, only 2.5% of eggs in the current study were laid on the floor in Year 1, and 0.3% in Years 2 and 3; 1.7% across all years. Hen mortality was variable across production and molt periods, and did not differ due to housing system (P > 0.05). The results of this study confirm that hen productivity in well-managed alternative housing systems can compare favorably with that in battery cages.