Need help, sick goose

[Nuit Etoilee]

I just found one of my adult Toulouse exhibiting neurologic issues. Head tilt and nystagmus.
All of my other geese, ducks and chickens are fine.

 

[Goosebaby]

This could be caused by a number of issues, it could be encephalitis from bacteria or a virus, if that’s the case you may want to get them seen by a vet as soon as possible to determine if it’s something contagious so you can pre treat or vaccinate the others before they come down with it.
Another possibility is poisoning. Lead and zinc overdose can cause neurological conditions, most commonly they lose the ability to walike, in much higher levels of toxicity it will affect the brain, possibly like this but you’ll also be seeing seizures.
Pesticides are another possibility.

Another is a stroke or head trauma, I had a gander that was attacked by a dog and showed similar symptoms for a few days after which he began to improve but didn’t regain control of his eyelid for about two months.

 

[Goosebaby]

You could also give them vitamins, E or A if I remember right can cause neurological problems if they’re too low, too little of the Bs can cause issues too.

 

[Miss Lydia]

Vit E along with selenium, this is the treatment for wry neck or star gazing, but for an adult to start this I'd say a vet would be best for a diagnosis. Could there have been head trauma?