http://www.fsis.usda.gov/Science/Chemistry/index.asp

How would I find this weekly list you mention, usuba dashi?

I agree that organic is the way to go. Proof is the weekly list the USDA posts on their website with the consistent violators whose products contain residual antibiotics. Guess who is number one . . . . the conventional milk industry over the meat industry. Still with organic for the sake of your family.

Hormone free and organic is most important, in my opinion. If we're taking about percentages, I've heard that 1 or 2% is actually better than skim, as they have less sugar as opposed to skim, which has more sugar and less fat. But I'm not a milk drinker.