I brought home the chicks 4days ago and was told they were about 1week old. So they're maybe 1 1/2 - 2 weeks old.
Splayed Legged Chicks - Page 2
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Even though it might not be successful I would treat them. The earlier it is treated the better the chances are. Vitamins always can be a good idea with leg problems. Good luck. Here are a couple of links to help you with the leg hobbles:
The main thing is to figure out if it is really splay leg, and not a slipped tendon which is hardly ever fixable. It's always worth trying.