Hen Mortality in Intensive Systems: Welfare Significance of Flock Death Rates

Mortality rates in laying hen flocks are both a welfare indicator and a production metric. Understanding what drives mortality helps identify welfare problems and target improvements.

Key Facts

Mortality rates in commercial laying hen flocks typically range from 2 to 15 per cent over a laying cycle
Mortality can be caused by injurious pecking, infectious disease, respiratory problems, and heat stress
Mortality due to injurious pecking indicates underlying welfare problems including crowding and enrichment deficiency
High mortality in cage-free systems compared to conventional cages has been used to argue against welfare improvements
However, higher cage-free mortality often reflects management failures that are preventable with appropriate care
Vaccination, biosecurity, and management interventions can reduce infectious disease mortality significantly
Monitoring mortality by cause enables targeted intervention rather than accepting preventable deaths as normal

Welfare Considerations

Flock mortality is a welfare indicator that deserves attention as a signal of underlying problems rather than as an acceptable production statistic. When mortality from injurious pecking is elevated, it indicates that the flock is experiencing conditions that drive redirected aggression, requiring investigation of enrichment, stocking density, and management factors. When infectious disease mortality is elevated, it points to biosecurity failures and vaccination gaps. The argument that cage-free systems have higher mortality than caged systems is technically accurate in some contexts but reflects management failures rather than inherent problems with cage-free housing. Well-managed cage-free flocks with appropriate enrichment, biosecurity, and stockperson training achieve mortality rates comparable to or better than conventional systems.

What You Can Do

Support egg certification schemes that require mortality monitoring and reporting as welfare indicators
Advocate for cause-specific mortality analysis rather than simple total mortality as a welfare metric
Learn about the welfare implications of different mortality causes in laying hen flocks
Choose egg products from producers with documented low mortality and transparent reporting
Support research into mortality reduction in cage-free systems through management optimisation