Not all feeds contain antibiotic or arsenic. Just like human food better look at the ingredients label. If you can't figure it out, better not eat or feed it. Garbage in - Garbage Out! Organic Feed is not always the answer. Just because Organic doesn't mean quality.
Here's a recipe for home made feed: Cracked corn and cracked wheat (non Gmo) (Hutterites sell it), Alfalfa meal and/or ground peas, about half the mix.for protein and trace elements. Free Choice Oyster Shell. Mix in some Livestock salt with Minerals or order some Poultry Base Mix from WolfKill or other supplier. A little flax , canola, meal is also good. For young chicks add fish meal for more protein. Offer birds produce and fruit scraps, lawn clippings and meat scraps if chem free. Only give what they clean up right away. Kelp for trace elements. This is what we fed our birds before we got a grinder-mixer for doing large qty.'s
PS: If you have a barn or corral area with a lot of flies and other bugs, free ranging chickens are great for pest control.
The ingredient to look for on the label of your chicken feed is roxarsone. This is the arsenic based additive you want to avoid. You can buy meat, vegetables and eggs from Rocky Ridge Ranch at the Millwood and South Perry Farmers' Markets. The picture is of Gary's laying hens on the ranch.