their is a topic on this page called i just had to rescue them and it talks about how to keep them alive longer.
in normal meat places the cornishX are killed at 4 weeks so you may be able to keep them around longer but i don't think long enough to lay
but the good news is they are very docile and not flity at least
I've heard that if you don't butcher them, they're very prone to health problems due to their growth rate and size. Much like the large breasted turkies, I'd imagine they'd be prone to heart attacks as well, and even if you don't butcher them, probably won't live long enough to lay any eggs. They weren't bred with longevity or egg production in mind, but to be able to provide a lot of meat in a short amount of time. I hope it goes well for you, but don't be surprised if they don't survive very long.
You can do all those things, but they are still not going to live as long as other birds. Best thing to do is raise them for meat and get a couple of others if you want pets. These birds are bred to eat, gain weight and be butchered no later than 12 weeks old, I think that withholding food from them is not particularly humane as they would feel hungry all the time. JMO
the first time i ever raised cornish x's i got a batch of 70 and raised them with my 30 egg hens right from the start. they free ranged daily (after around 4 weeks) and climbed the ramp to their roost with ease. occasionally they would even "fly" up to a distance of 10 feet or so. they lived the life of a normal, happy chicken, not some franken-bird. i had four hens that i did not get around to processing right away so i decided to raise them longer and they turned out to be pretty reliable layers of large, brown eggs. they did not ever end up having heart problems or go down on their legs. they lived a happy life all the way, although they were harvested at around 10 months because it became impractical to feed those hungry girls (and MAN they were big at that time.. they looked like giants among the other hens).
my birds do get ACV as chicks and occasionally as adults... but for other health benefits (i hadn't heard it could prolong broilers' lives..not sure about that..). as far as overeating, they free-ranged the majority of the time and actually chose to NOT camp out in front of the feeder although food was always present during the day. i swear, seems no one told them they were cornish x's.
but yes... for a NORMAL cornish.. they will NEVER live a normal, LONG life. they just simply aren't bred to do so. that doesn't mean they can't live a happy life while they are here!
thanks this helps me a lot i had no idea what they were they are defiantly Cornish cross i free range all my birds and i do not butcher them they are a month old now they only pant when its hot out , when is see them panting i just turn on the fans in the coup.