I really should have up-dated this at three weeks, but I haven't had the time. Sorry.
At three weeks the chicks averaged 14oz each. Currently the chicks are four weeks old, and average 1lb 8oz each.
All 20 chicks are still alive and perfectly healthy. They still can fly up and perch on the saw-horse that I'm using to hang they're light on, using a normal light now. Droppings are "normal", I'm using pine shavings with straw over the top as bedding. They still don't have any feathers under their wings. Only fluff and pin feathers along the keel bone and their heads.
I'm still feeding/providing light 24/7, and feeding the 30% Game Bird Startena for their whole ration. I got a bag of 20% Flock Raiser to mix with the 30%, but haven't started mixing it yet. The chicks have eaten though about 65lbs of feed (feeder has never been empty since I stopped the 12 on 12 off).
I'd really like to know how big your Cornish X chicks are at four weeks? Is it time to start removing feed and turning off the lights at night? Is it time to start mixing the feed? What changes would you make if these were your chicks? Anything else I should be feeding? Would a little Calf Manna be okay to mix with their feed? What do/feed you do to finish them (a little corn)?
I learned pretty early that the Cornish crosses are much more relaxed and easier to deal with during handling/examinations etc if I hold them in a cupped while they lay on their backs. They look really similar to this picture. before too long their feet stick out straight and they start to fall asleep. They look like they are in the winter olympics trying out for the luge. LOL. It's almost a tonic immobility position for them, similar to a pressure point on sharks noses that when pressed turns them into pussy cats.
When I'm done handling them, I put them back in the brooder in the same position and they can sleep for hours like that before they get hungry or thirsty and get up. It's about the only "cute" thing I've found with Cornish Crosses.
The similarities between the Cornish X and Shark,... That's going to lead to some unpleasant dreams.