Hello, I want to ask what do you mean by neurological? Are you referring to Marek's disease. My cockerel isn't getting any better, making me think he doesn't have a vitamin deficiency. I noticed that he can't clean himself (clean his feathers), he tries but he can't. He now can't stand on his feet very well, he is starting to fall on his back and can't get back up. I notice that he leans on his left side and falls to his back. Leans more on his head and his tail facing upwards than the usual. Is this Marek's disease? His droppings don't have blood or anything out of the usual sometimes a bit runny but nothing out of the ordinary. He doesn't want to eat the chick starter feed nor drink water. However, he does eat food like spaghetti, green beens, etc. Strangely doesn't eat egg. Do you have a clue on what it could be besides vitamin deficiency? I feel like he might not make it.