Keel bone fractures affect up to 80% of commercial laying hens in some systems, causing chronic pain that impairs normal behavior and represents one of the largest unaddressed welfare problems in animal agriculture.
Keel bone fractures cause chronic pain that is clearly detectable through behavioral and physiological indicators. Affected hens spend more time resting, feed less efficiently, and show reduced social engagement. The welfare scale is enormous — potentially hundreds of millions of hens living with untreated chronic pain globally. Diagnosis requires handling every hen, which is practically impossible at scale.