Credit to Mark's Daily Apple for this post.
Here is a short clip from the article. It's a prioritizing of purchasing chicken.
"Here’s how I’d prioritize the options.
1.Pastured – It’s harder to come by and pricier than organic, but the poultry offers more nutritionally through extra nutrients like vitamin E, folic acid and B-12 as well as more omega-3s. Even though pastured chicken might not be labeled antibiotic-free, it’s likely the farm doesn’t use medication. It’s extra work to pasture birds, which indicates a greater commitment on the farmer’s part. Plus, the chickens are less likely to need antibiotics when they live on a natural diet with plenty of space.
2.Organic – Although pastured chicken provides nutritional extras, organic poultry at least ensures that you’re not getting a dose of pesticides, arsenic, and antibiotics with your dinner.
3.100% Vegetarian Feed - If a chicken isn’t pastured, the non-vegetarian part of the feed is likely animal by-products. Need I say more?
4.Antibiotic-Free – This one’s probably self-explanatory.
5.Free Range – Sure, free range can mean a lot of things, but it at least suggests there was some opportunity for movement and a slightly healthier/more humane living environment. It’s a tough call but probably better than fully conventional. This is a case where it’s especially helpful to know the farmer/company and the particulars of their practice.
6.Conventional – Regardless of where you live, you should be able to find poultry that ensures vegetarian feed. Personally, I’d suggest staying away from chicken that can’t promise that much. That said, as with other meats, if conventional is all you can afford or have access to it’s better than no meat at all. Just eat the leaner cuts, since toxins concentrate in fat."
Happy shopping!