These are the dosages for vitamins in treating wry neck for a 2+ lb bird or an adult bird. Just scale back slightly if the duck is smaller.
- Vitamin E: 400 iu once a day
- A squirt of vitamin B complex liquid
- Selenium should also be given to help the duck absorb vitamin E. The dosage is 25 micrograms a week. Do not overdose on the selenium as it is toxic to poultry if given in too high a dosage. You can also supplement selenium naturally in the diet with Cayenne Powder, Oregano, Basil, Parsley, Cloves, Sage, Thyme.
- Some feeds have selenium in them so extra may not be necessary, so check the label on the feed bag to see if selenium is in the feed. I would recommend choosing to either give selenium itself or supplement it naturally, but not both options together. If the feed contains selenium, you may not need to supplement as long as you continue to see improvement in the wry neck.
- Vitamin E and B are tolerated better in poultry and are harder to overdose with so don't worry about those.
- I would also try supplementing with some niacin, like Brewers yeast, in the duck's feed.
- Vitamins and electrolytes might also help (just be sure to adjust the vitamin E and B dosages above if you use a vitamin/electrolyte mix).
I have a goose with wry neck that I have been treating for 2 months now. Wry neck treatments take time and it seems like you have done well so far.
Good luck with treating the wry neck and I hope your duckling feels better soon.