Yup, they are meat birds...and their body cavity does not grow as fast as their meat.
So the liver, kidneys & heart remain smallish compared to the enormous amount of flesh they will develop.
We raise ours as soon as the weather gets decent, since the Cornish X has few feathers.
They went out on free range & were therefore forced to eat grasses.
I then fed them a scoop of feed mornings & a scoop evenings consisting of Flockraiser or similar 20 % protein or higher.
As they develope more flesh, faster than average laying birds, these Cornish need a higher % protein feed.
To keep them lean & active, I rationed their feed intake & removed the feeder after 20 minutes, otherwise the gluttons will park their butts at the feeder 24/7 and never move out of their own poo.
Our birds dressed very nicely with much tender felsh and hardly any fat and fantastic flavor no commercial poultry has, that due to the free range.
So, end of March, we get out 50 "CornBalls" and raise them in the brooder til about mid April when I can no longer stand the poopy dudes...and out they go to a "grow out" pen with high soft new spring grasses.
At 8 weeks we butcher most all but smallish cockerels.
At 10 weeks we butcher the hens.
Good eating all year long.