Well my thoughts are (and I'm no scientist) a broiler chicken isn't a normal chicken. In about 8 weeks they are almost too big to walk. So in 5-6 months how could they lay a egg to hatch? My thoughts are that is a GMO bird? I don't know just my thoughts? And I've been wrong before. I would just like to get back to something close to what God made.
I'm still not totally clear what you are after. GMO can mean different things to different people. For many of us that means messing with things at the DNA level with gene splicing and such. In spite of a lot of misinformation on the internet and other places, that does not apply to any chicken. None. Nada. It is just not true.
Some plants that produce the food we feed our chickens have been modified by gene splicing. To avoid those you need to feed them non-GMO feeds.
The Cornish X and the chickens that lay eggs commercially have been developed by selective breeding. Around the 1950's scientists who studied genetics were able to develop the Cornish X meat birds by choosing the parents and grandparents wisely. This was long before gene splicing. I'm not sure when the egg laying hybrids were developed but it was the same idea. The geneticists carefully selected which chickens got to breed and were able to develop these specialists.
By selective breeding they were able to develop meat birds and egg laying birds that were as good as you could get. They had great food to meat or egg conversions. If they gained weight any faster their bodies couldn't handle it and would break down. Or if they laid more or larger eggs the egg quality was bad or the hens had health issues because hens just could not handle it. They did not need any expensive gene splicing to produce a more productive chicken. The meat birds are so efficient that they need to be butchered at a certain size or their bodies will break down. Similarly the commercial egg layers tend to have more health problems, especially if they are overfed.
The parents of the Cornish X are kept from growing so large they cannot mate or live long enough to lay eggs by restricted feeding. They need to be fed enough of the right nutrients to keep them healthy and laying plenty of good hatching eggs without them getting too big. It is a really exact science that the professionals have mastered. Most of us can't do that very well at all.
All chicken breeds have been created by selective breeding. The reason barred rocks are black barred is that they were selectively bred to be barred and black instead of having some other color or pattern. The reason Leghorns lay white eggs is that they were selectively bred to lay white eggs. This type of thing has been going on since chickens were first domesticated thousands of years ago. People learned if they hatch eggs from their best egg layers those offspring tended to be good egg layers. If they bred for size they made better meat birds. Different breeds of dogs, cattle, and practically all other domesticated animals were developed the same way, selective breeding.
You are not going to find a chicken as God made them unless you can get hold of the wild jungle fowl chickens were domesticated from. You probably would not be very happy with them. They do not lay many eggs and they are really small, not much meat on them. It would be like eating a bantam chicken.
If you are talking about selective breeding producing a GMO chicken you are not going to find that in any chicken or really any domesticated plant or animal you eat. They have all been selectively bred. If GMO to you means gene splicing at the DNA level get any chicken and feed it non-GMO foods.
I know this is long and your eyeballs are probably rolling in their sockets by now. But I think you and many other people out there have some pretty strong misconceptions about this whole business. If I have been clear enough maybe you can now make an informed decision.
