Apple Cider Vinegar can kill worms in chickens.
Apple Cider Vinegar is a natural and pretty old home remedy for getting rid of worms in chickens.
To use apple cider vinegar to get rid of worms in chickens just add a small amount of apple cider vinegar into the chickens water.
The chickens will drink the water with the apple cider vinegar and when the apple cider vinegar enters the chickens gut the worms will start evacuating out of the chicken.
Whether they die or not they will come out of the chicken because the worms do not like apple cider vinegar or regular vinegar.
You can also cut garlic up in small pieces and add it to the chickens water as well and the garlic when consumed by the chicken will cause the worms to come out of the chicken.
Alternatively you can use worm medicine for your chicken which you can easily get either online or at most pet or farm stores.