Len wants to know about animal nutrition: >> That's my question. What part of the diet supplies the calcium? Grass? >> And what about carnivores? Do they eat enough bone of prey animals to get >> calcium? <snip> >That wasn't my question. My question was how do animals get by, not >people. Can't anyone answer this question without talking about people? > >Len Hi Len, As a pediatrician with a Masters Degree in Nutrition (obtained from the University of Illinois, where most of the nutrition research involves animal nutrition rather than human nutrition) maybe I can answer your question: You're right--cows get their calcium from the greens that they eat, and carnivores get calcium from the bones that they eat. Carnivores such as dogs actually EAT bones--it's a big part of their natural diet. They don't just chew the meat off and scrape the marrow (unless it's a very large, thick bone, like a femur); they crunch up, swallow, digest and pass ALL the bones of a bird or rabbit or young animal. I can vouch for this, because my dog eats bones. Raw bones, including chicken, lamb, duck and beef, have made her healthier than she ever was. (Not to mention the beautiful shiny white teeth and fresh breath she regained after starting on bones.) People can get a lot of calcium from dairy products, and if they are of northern european descent, they can do this fairly comfortably. If no dairy is consumed, there are lots of other places to get calcium. Another factor in calcium requirements is the calcium to phosphorus ratio. Meat has a lot of phosphorus in it, and eating this greatly increases your calcium needs. True carnivores get by by eating the bones, which humans rarely do. Vegetarian humans don't get as much phosphorus, and don't need as much calcium. The relationships between nutrients can be just as interesting as the nutrients themselves. Julia Winter M.S. M.D. General Pediatrician who studied Nutritional Sciences (Alumnus of UIUC's Med Scholar Program)