Chickens will lay until they no longer have eggs.
How you deal with Flock management, will determine how long you will allow them to live.
We keep quite a few chickens, and if I was to let them all live until they died, I would go bankrupt.
I am sure we will come across a hen or two that we will hang onto at some point, but for the most part,
it makes good business sense to keep them till they about 2 years of age at the most, keeping a new flock growing up to take over at the right time, and stewing the older ones.
One of the reasons I will never keep cochins as our main flock, is because of the much higher cost involved, due to them being such late bloomers, and patchy layers.
I did not research them well, and the person we bought them from led me to believe that they laid early and often
We will always keep a few for brooders though.
We are looking into spiral breeding right now, and contemplating what breeds will work best.
Cute chickens by the way