Comparisons of Bone Characteristics Between Floor and Battery Grown Broilers

RECENT developments in the broiler industry, namely increased labor costs and disease problems, have initiated interest in growing broilers in colony cages and coops. It has been established (Rowland et al., 1968) that caged layers have a lower bone breaking strength than hens on litter in floor pens. This decreased bone strength of caged layers causes down-grading of processed hens which can be of economic significance. Lloyd et al. (1970) reported 22.2 percent bone breakage from broilers grown in plastic coops as compared to 8.6 percent for those grown in floor pens. It has been reported by Trueta (1968) that lack of muscular activity can be a factor in the development of osteoporosis in humans. Rowland and Harms (1970) demonstrated that using pens with wire floors did not decrease either tibia ash or tibia breaking strength; however, breaking strength was decreased for those hens maintained in cages. These workers indicated…