Explanations for keel bone fractures in laying hens: Are there explanations in addition to elevated egg production?
The current article served to provide the most up to date information regarding the causes of keel bone fracture. While elevated and sustained egg production is likely a major contributing factor towards fractures, new information resulting from the development of novel methodologies suggest complimentary causes which should be investigated. We identified four broad areas (Age to first egg, Late ossification, Underlying disease states, Inactivity leading to reduced bone strength) that could explain variation and increased fractures independent or complimenting elevated and sustained egg production including: the age to first egg, late ossification of the keel, predisposing bone disease, and inactivity leading to poor bone health. We also specified several topics that future research should target including: continued efforts to link egg production and bone health, examination of non-commercial aves and traditional breeds, manipulating of age at first egg, a detail histological and structural analysis of the keel, assessment of pre-fracture bone condition, and the relationship between individual activity patterns and bone health.