Hen keel bone fractures are a serious welfare concern, due to their high prevalence in some cage-free systems. When hens have a keel bone fracture, they show indications of pain, eat and drink less, are lighter in weight, and have reduced egg production efficiency and quality. There have been few research studies exploring the prevalence of keel bone fractures specifically in U.S. commercial systems. In this case study, keel bone data was collected from 3 different U.S. cage free systems (terrace, fienhage, and single-tier). One hundred hens, 50+ weeks of age, were randomly selected from each farm. A trained evaluator assessed each hen using the Welfare QualityTM tool, with modifications to provide further detail of keel damage. In these flocks, the most common keel abnormalities were keel deviations (median= 79), whereas prevalence of fractures (median= 34) was lower than reported in some studies. Additional flocks will be enrolled to explore impacts of potential risk factors, such as housing system, genetic strain and rearing environment
