At least this is what I believe. I have applied it to dogs and children and cows.
The problem when applying it to cows is that a cow spends an amazing amount of energy digesting and there is some number of "chews" a cow will make in a day. So, if she is eating rich food, her number of chews will result in a different condition from a cow eating lower quality food.
Violet is definitely eating with more interest since we are offering up an entire round bale for her to sort through and waste at her leisure, but she still is not looking all that great. This is our first year using wrapped bales, but the bales are from the same fellow we got hay from the year before. My guess is that the hay is fine, and my cow is just suffering from being the mother of twins at the end of winter.
People keep telling me that two weeks on grass is all she needs, but we're at least two, and more likely three or four, weeks from being able to graze. We're offering trace minerals, loose salt, and kelp, but I wonder if better hay would help her.
The real answer is to not have a calf in March again. November was fine, June was fine. Next time, I think we'll try for April or May; everyone will still be confined while the calf is very small, but it won't be so long before Violet can get back on grass.