Had a friend bring me a day old chick yesterday that could not bend the knee. It was partially bent but could not be straightened or bent further almost like it was fused. Doesn't appear to be slipped tendon or splayed leg that I have seen in the past. The only other thing to mention is the back of the hock almost has a bruise on it. Chick was hatched on day 21 like this. Eyes were not opened yesterday but are now today. Drinking but not eating. Ideas?