You also really have to ask about the meaning of "grassfed beef". I live in Wyoming, where every rancher claims his meat is "grassfed", and wholesome and healthy. But...
If you question them about winter feeding, they admit that they supplement with cake in the winter. And it is medicated, hormone enriched, "nutritionally balanced" (that means full of extracted nutrient blends and chemicals).
Most ranchers don't really know what is in that cake, or if they do, they've been brought up on the common ranching tradition that if it is made for cows, and the cows don't die from eating it, that it must be good and people are silly if they complain about eating cows that have been fed the stuff. And the ranching lobbies, and feed company lobbies work hard in Washington making sure that cows do not have to be raised with the same regulations that chickens do (not that chicken is a whole lot safer, but hormones and "non medical" antibiotic use is forbidden - though they put other stuff in medicated feeds for chickens). They like how things are done, and do not ever want to have to change it, so they proudly claim that their cattle is grassfed, and never mention to you that they cake them - if you see where they are raised, you see only the pasture they want you to see.
The antibiotics in that supplemental feed makes me prone to fungal infections. It is responsible for the superbug e coli that got me sick two weeks ago (which didn't come from my raw milk, or my homegrown chicken eggs, or my manure fed home vegetables, or my home butchered duck or rabbit - it came from a bottle of contaminated nationally branded dairy product from factory farmed dairy cattle fed medicated feed, in a USDA inspected facility). And BTW, I am NOT immune compromised in any way, I rarely get sick, and when I do, it is about half as bad as other people with the same thing - can't imagine how bad that e coli would have been for a normal person, I think they'd have been hospitalized with dehydration.
The RBGH (recumbent bovine growth hormone) causes serious hormonal imbalances in girls and women, and minor ones in adolescent boys, because of the way that it interacts with our pituitary gland. If you are having hormonal imbalances, go to 100% organic animal products (or look for RBGH free meat and dairy) and it is likely to get better (even though "organic" products still aren't 100% clean, they are usually better than the regular stuff).
The artificial hormones in beef and dairy can cause heavy menstrual periods (I use the term "heavy" to mean "HEEAAAVYY"), ovulation problems, pregnancy implantation failure, cell regeneration (that means "healing") problems, PMS issues, and many more.
So, no Wyoming "grassfed" beef for me unless I know for certain that it has not been fed cake at all. Colorado, Texas, Kansas, etc, all follow the same rules.
Sort of like Taco Bell's meat - as long as it is mostly grass, not mostly corn, it's "grassfed".
Funny thing, I've mentioned that cake to a couple of people locally who claimed that they were getting the healthiest meat available and they knew it didn't have medication or hormones in it because they were buying it right off the range. They all but accused me of lying - yet when I asked the rancher they bought their beef from, he said, "Sure, we feed them supplemental cake in the winter, everybody does." Sure enough, every rancher I ask says the same thing. Difference is, I ASKED, the other people did not!
And the only reason I KNEW this, is because my son worked on a local ranch, and talked about caking them in the winter. So I asked what was in that cake. He asked, was told, so I knew what everybody does, but nobody talks about to the customer.