I would be more inclined to give a multi B complex. B12 and thiamine B1 deficiency can certainly cause these problems .
http://www.merckmanuals.com/vet/pou..._poultry/vitamin_deficiencies_in_poultry.html
http://www.merckmanuals.com/vet/pou..._poultry/vitamin_deficiencies_in_poultry.html