Today’s commercial laying hens have been selectively bred to produce more than 250 eggs per year. This unnaturally high level of productivity is metabolically taxing, often causing hens to suffer from “production diseases,” including osteoporosis and accompanying bone fractures, and can lead to reproductive disorders. Research suggests that the problem of osteoporosis may be worsening, possibly due to industry’s continuous push toward maximizing productivity. For decades, economic considerations have been valued and emphasized over the welfare of individual birds. An immediate change in priorities is needed to aggressively address welfare problems associated with selective breeding for egg production.
The Humane Society of the United States, "Welfare Issues with Selective Breeding of Egg-Laying Hens for Productivity" (2007). IMPACTS ON FARM ANIMALS. 13.