How's it all work?

[animalspooker]

Considering raising meat chickens, but would like to have them hatch chicks before the slaughter so I don't have to buy new chicks every time. My question is how exactly do they lay and sit on their eggs? Well, I know how they do that, but how many eggs will a hen sit on, and do they stop laying once they-start sitting? Will they sit on each other's eggs? Will some sit and some refuse? Where can I find answers to these questions?

 

[countrygoddess]

That probably won't work unless you keep some as breeders because slaughtering generally happens before they start laying. Also, you'll have to get something other than Cornish X because they really can't breed naturally. There are all kinds of breeds that are super-tasty as table birds. One of my very favorites that I pulled from my freezer was an Ameraucana cockerel (I hatched chicks to add to my laying flock so of course had a bunch of cockerels as a result). We also very much enjoyed one of Blue/Black Marans we processed and the carcass was really good-sized at 20 wks (over 4 pounds). Salmon Faverolles are very good, as are Dorkings.

 

[ChickenCanoe]

If you're using Cornish/Rocks (the predominant market broiler) as your meat bird, it won't work.
If you're using a heritage type bird, for example Dorking, Australorp, Java or Brahma , it can work.
Some breeds tend to go broody some rarely do.
A broody hen won't lay eggs once she sets. That would cause some embryos to die when she leaves the nest to care for the first chicks. They lay a clutch, hormones change, egg laying ceases and she goes into the broody trance.

Cornish aren't setters and IME neither are Rocks.
Cornish/Rocks aren't meant to live more than 7-12 weeks - too soon to lay or breed.
They are created from a male line (white Cornish) and a female line (white Rocks) so therefor won't breed true even if they live long enough and are agile enough to copulate. Then the hens probably won't go broody. Most Cornish cross in the world come from 7 mega corporations.

If you want a renewable meat bird, best bet is to breed a heritage type bird possessing good meat characteristics and have an incubator or keep a few broody breed hens. i.e. silkies, cochins, etc..
The number they sit on depends on the hens' size. A silkie my be able to cover a half dozen large eggs, while a LF cochin perhaps a dozen or more. They absolutely sit on each other's eggs so once a hen goes broody, it's important to mark the eggs so you can remove volunteers. When multiple hens are broody, they'll steal each others eggs so separating broody hens is the best practice.

Broodiness is a hormonal change. You can't force it and most breeds have had broodiness bred out of them.