3day old PBB legs

[upper20s]

Hi guys-I'm raising four barred rocks for a friend who bought them locally at a chain store.One leg is laying straight out behind. The joints are usable ,she does have control over when she stands upright to go walking but she trots and then she stumbles she'll stand up shake herself off.friend's first time buying chicks this one is quite a bit smaller than the other ones definitely a runt was picked on cuz there's a little bitty red spot on its head with little white stuff hanging from it I've doctored. I don't know if this is neurological or if because it's a runt it will grow and learn to use its legs?l using vitamin pack mixed with water using it to softener food she's eating very well. My question I always get my chicken shots from the hatchery since this didn't come from a hatchery is it possible for her to have one of the diseases that you guys talked about and if so what do I look for I've had her 24 hours and she's not around my chickens have had all their shots from McMurray.

 

[Wyorp Rock]

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