Bison patties contain the whole animal except the heads, hides, bladder and large intestine (manure), hooves, horns (if any). We do not use non-edible bones as these would not be consumed in nature due to their density. Organs make up approximately 8 to 10 % of the patties - this includes lungs, liver, heart, kidneys and the tongue. The omassum from beef is saved for our green tripe patties. On average over all our protiens, patties are composed of 66% muscle meat, 7% bone, 10% organs, 7% blood and 10% fat. Other than the vegetables and fruit in our dinners we DO NOT add anything to our foods. You may supplement as needed. Please ask for a brochure or visit our website for healthcare and supplement products. Like beef, bison is an excellent source of iron. The meat has yellow fat which means it is high in beta carotene. Bison do not marble (put fat in the muscle). The result is more meat (protein) and less fat (calories) per pound. The taste is often indistinguishable from beef, although bison tends to have a fuller, richer (sweeter) flavor. It is not "gamey" or wild tasting. Bison is a good red meat alternative for pets allergic to beef.