Though they are typically slaughtered as young as 42 days old, with proper care large breed chickens can live much longer than that. Females typically live 6-8 years and males typically live 4-7 years, but there have been individuals who have lived to the the ripe old age of 10! However, due to the way they have been bred, they are predisposed to certain health challenges. It is important to understand these challenges and keep them in mind when caring for these amazing beings.
Cornish Cross and other large breed chickens (referred to as “broilers” by the meat industry) have been selectively bred by humans exclusively for the purpose of increasing their body mass and growth rates to make them more efficient to raise and slaughter in vast numbers while increasing overall profitability to large scale farming operations. Cornish crosses now reach industry “slaughter weight” after only 42 days. The industry is actively trying to speed up this growth rate, which will only create more health challenges for them in the future.
This genetic propensity towards rapid growth contributes to a variety of devastating health challenges, especially leg and joint problems and heart failure. A 2008 study of over 50,000 chickens discovered that, by 40 days of age, over 27% of the chickens had impaired walking capability and 3.3% were nearly unable to walk.