That shouldn’t matter. They have bags of cat and dog food, and then all the other bagged things - chicken feed, seeds, and more.
Number of stores shouldn’t matter . It’s a culture from the top down that waste doesn’t matter
What do they say?
That’s true. Beyond a taste test, horses don’t care of protein comes from soy or peas. Their body cares whether they are getting enough quality protein (so not just protein, but usable amino acids).
Every feed has to have a GA for a set number of required nutrients. There are allowances for each of those, smaller or larger depending on whether it’s a macro or trace nutrient (gm vs mg), and how sensitive general tests are for that nutrient. Some companies add a few to a lot more nutrients to their GA. Some are somehow getting away with not listing a few of them - IME that’s low end, locally milled stuff
They aren’t wrong, necessarily. Purina has “least cost” ingredients in a lot of their feeds, which is not the same thing as choosing different ingredients on a regular basis just for cost. It’s cheaper to have a tag that said “grain products” if your choice of grains varies drastically from one part of the country to another, and to bring the quality oats (for example) 3000 miles away just to keep the same ingredients would raise the cost too much. So, the same tag can be used in different areas. Even then, I have seen 2 different tags for Strategy from different parts of the country
Quality companies test all their main ingredients for aflatoxins, mold (for corn usually), and even nutritional content. Fixed ingredient, but not fixed formula feeds will then adjust the added nutrients to meet the same GA, based on the analyses of the main ingredients.
Fixed formula feeds which still meet the GA use main ingredients that have a tighter set of parameters for variances. Triple Crown is one, and there are some others that I don’t remember. Seminole may be one, not sure about Blue Seal.