Most chickens do not recover from Mareks symptoms, but it rarely can happen. Calcium and phosphorus in a correct ratio, along with vitamin D3 are important in leg development. Most commercial feeds will have the correct amounts. Layer feed contains 4% calcium which is important in chickens who are laying. All flock or flock raiser feed has 1% calcium which is good for non-layers, roosters, and chicks. Here is a good link to read about calcium and phosphorus:Thanks Eggcessive!
I know video is so much more helpful then words, I don't have anything capable of taking video at the moment, sadly.
So you recommend wait and see. If they recover, do you know how to tell if it was Mareks or something nutritional?
I'll take the opposite stance, I would cull.these new teenagers may have been raised on layer feed from birth, and that much calcium can lead to the same symptoms as not enough calcium, correct?