Relationship of pen height to bone strength of broilers

Broilers reared in cages have a high incidence of wing breakage during processing. Three trials were conducted to determine the effects of cage dimensions and floor types on bone breaking strength and wing breakage during processing. Broilers were fed commercial-type diets and processed through the pickers at a commercial processing plant or a research facility. Broken bones were detected by palpation, and humeri and tibia were removed. Breaking strength was determined for the humeri and tibia with a testing instrument. Incidence of breast blisters, crooked keels, follicle infection, fleshing downgrades, and slabsidedness were determined in one trial. Cage height was the major factor affecting wing breakage and humerus strength. Incidence of wing breakage for broilers on wire floors with cages .64 m high was not significantly different from that of control broilers reared on litter with ceiling 2.54 m high. Humerus breaking strength was significantly reduced in two of three trials by the .64-m-high ceiling. Cage rearing increased the incidence of crooked keels and feather follicle infections.