Welfare Footprint found: ”mortality in cage-free flocks is not inherently higher than those housed in conventional battery cage systems but rather declines as managers gain experience and knowledge over time. When comparisons are made between systems with similar levels of technological maturity, mortality is similar in different systems. [...] It is important to note that lower mortality or longer survival of hens is not necessarily a good indicator of health or welfare. What makes animals suffer is not necessarily what kills them: unhealthy individuals can suffer for extensive periods in caged conditions before succumbing to their fate, if they die at all.”[1]
“Cage-free aviaries were found to be clearly superior to conventional cages and furnished cages even soon after a transition to cage-free environments. Overall, an average of at least 275 hours of disabling pain, 2,313 hours of hurtful pain and 4,645 hours of annoying pain are prevented for each hen kept in an aviary instead of CC during her laying life, and 1,410 hours of hurtful pain and 4,065 hours of annoying pain prevented for each hen kept in an aviary instead of a FC during her laying life.”[2]
Welfare Footprint found:
”mortality in cage-free flocks is not inherently higher than those housed in conventional battery cage systems but rather declines as managers gain experience and knowledge over time. When comparisons are made between systems with similar levels of technological maturity, mortality is similar in different systems. [...] It is important to note that lower mortality or longer survival of hens is not necessarily a good indicator of health or welfare. What makes animals suffer is not necessarily what kills them: unhealthy individuals can suffer for extensive periods in caged conditions before succumbing to their fate, if they die at all.”[1]
“Cage-free aviaries were found to be clearly superior to conventional cages and furnished cages even soon after a transition to cage-free environments. Overall, an average of at least 275 hours of disabling pain, 2,313 hours of hurtful pain and 4,645 hours of annoying pain are prevented for each hen kept in an aviary instead of CC during her laying life, and 1,410 hours of hurtful pain and 4,065 hours of annoying pain prevented for each hen kept in an aviary instead of a FC during her laying life.”[2]
[1] https://welfarefootprint.org/2021/04/21/meta-analysis-mortality/
[2] https://welfarefootprint.org/laying-hens/