Influence of Aviary Design on Musculoskeletal Health and Keel Bone Damage in Hy-Line Brown Laying Hens

Bone fractures and keel bone damage as a result of osteoporotic implications on skeletal health due to high rates of egg production are of significant concern in the egg industry. This study was conducted to evaluate the effects of two aviary housing configurations and associated exercise opportunities on musculoskeletal health in laying hens. Two commercial aviary designs were compared: Big Dutchman NATURA STEP (STEP) and Big Dutchman NATURA 60 (N60). Musculoskeletal assessments were performed at 60 weeks of age (n = 180), where measurements included CT imaging and radiography, muscle dissections, tibial and humeral biomechanical properties, and bone ash percentage. Results indicated that hens in the STEP aviary exhibited higher tibial breaking strength, humeral stiffness, and heavier muscle groups compared to the N60 system. However, rates of new and old fractures, as well as rates of deviation, were more prevalent in STEP hens compared to N60 hens. These results indicate that housing system design influences musculoskeletal health in laying hens.