FDA and rBGH
The FDA says that no test can distinguish between rBGH treated milk and non-rBGH milk. This is because the FDA doesn't have the competence nor purse to use modern scientific techniques such as bioelectric field sensitivity or other cell health measurements and the subsequent effects on their produce.
Ill-helped cows are sicker, require more antibiotics, have a higher body fat ratio, and experience numerous maladies that they pass on in their meat, milk, and cheese, and hopefully not in their DNA.