The only way for sure that you can tell if it's merek's is by taking him into a lab and have him tested, of course, they prefer to have the chicken alive in which they will cull him. It does seem like it's going forward but He also pulls it back and walks on it. It also looks like he's walking on the back part of his leg not the part where his nails are so he is protecting that leg. Which indicates possible soreness or injury. If he is pulling or stressing when you touch that leg, i would say he injured it. With Mereks they get paralized, they usually don't feel a thing so therefore he would have no reason to pull back. I am not an expert but have had several experiences with leg problems. Right now I have a silkie that got string so tightly wrapped around her feet it cut the circulation off and she is limping something horribly..Here is a video.
My wonderful DH set it up for me. Its a bit shaky and the it has a bit of glare. The first few seconds really shows how shaky he is. After a few minutes though he stopped doing his leg back thing and would not perform for the camera...go figure. You can really see it though in the first few seconds as he walks toward the far wall, then turns around and tries to run back past the waterer. Its the best I can do since he acts like Im a big bad wolf!
Thats Stumpy in the brooder with him. Dont worry, hes not stuck under the roost bar, he just likes to sit there for some reason....maybe its because its by the food.
I really need to know if its Meraks. If it is, Im going to cull and sanitise.
He is 6-8 weeks old, no other symptoms, just the leg problems. He is on vitamins and antibiotics. He gets medicated chick starter. He has not come into contact with anything different than any of the other chicks. The brooder is filled with shavings. The waterer is cleaned every morning. All the chicks have all been fed, handled and treated the same. No symptoms are in any of the other chicks. The others are real close to the same age. All but Stumpy have come from the same breeder. The breeder is not currently having any issues with any of her flock or chicks. Her adult flock free ranges with turkeys. The chicks have only been outside once, about 2 weeks ago on the lawn for about 3 minutes each. They ate nothing. I have not gone to the feed store since getting these chicks, so i doubt i would ahve tracked anything back on my clothing or shoes. I dont know or visit any other chicken owners.
I personally would keep up with the Vitamins and work with him, I don't think antibotics is really going to do anything for him. If he injured it or even if he has Mereks antibotics is going to do nothing for him. So If you want to stop that you can but keep up with the Vitamins. exspecially Vitamin B-2. He will either recover or get worst. If you see that leg going forward to where his is down and can't walk at all, then I would say definitely Mereks and cull him. But right now, since he is using it, I would keep up with the Vitamins... Did I read right that you said the other leg is going backwards? I'm not seeing that in the Video, check out her skin, see under her feathers, does her skin look flaky? Flakiness is another sign of Mereks, in fact from what I know that is one other way how the other chickens get it by inhaling the flaky skin...
Tell me the history, did you hatch her or did you pick her up, if you picked her up from somewhere did you confine for at least a month? How long has she been like this? how long have you had her that is if you picked her up somewhere. If she has Merek and you picked her up from somewhere, usually the move will stress out a chicken and put the disease into overdrive, sort of speeking. How does her poop look like? is there any diarear? Feel her body, does she feel skinny? Does she eat a lot and seem like she's not gaining a pound? This is just some other things you can look for to determine, of course, it's different with every chicken but perhaps this will help you determine if possible Mereks or just an injury... Also check her crop, does she fill it at the end of the day and is it empty by morning, to determine this, try giving her as much food as possible during the day, then when it's bed time take the food away, feel her crop, in the morning when you go to give her, her food for the day feel the crop first... if it's empty that's a great sign her system is working... How much polyvisol are you giving her? For the Vitamin B-2 you can take a pill and drop it in her water the pill will melt, it will make the water yellow but at least you know she's getting a good shot of it.
hope this helps you a little....