"Natural" additives to feed?

[Anabariful]

What are some natural spices and such that you add to your flock's food and water? How much? How often?

I've heard of apple cider vinegar to water at about 1 tablespoon per gallon and cayenne pepper sprinkled to feed.

 

[JaeG]

You can feed garlic, free choice. Don't mix it into their food or add it to their water as you could put in too much and end up with garlic flavoured eggs. They know how much they need. You can also offer cayenne pepper free choice to avoid giving them too much which can be hard on their digestive tract.

http://naturalchickenkeeping.blogspot.co.nz/2013/06/the-benefits-of-garlic-cayenne-and.html

I've read apple cider vinegar can affect their ability to absorb calcium so it's better kept as a winter supplement. Baking soda can be a good supplement in summer instead.

http://www.the-chicken-chick.com/2012/07/make-raw-apple-cider-vinegar-acv-with.html

I give mine dried kelp for a mineral boost, specifically for the iodine as soils in New Zealand are low in this mineral. I do a pinch per bird.