I've listened to some pasture Pig Farmers talk proudly about not feeding their pigs "Animal by-products". I don't get it. Aren't pigs omnivores? Even if you're not feeding pigs animal by-products, aren't they eating animals in the field? A mouse, rat, rabbit, bird, chicken eggs, etc, the pig may come across in the pasture? What's the big deal about not feeding your pig part of the natural diet of an omnivore? Or am I just simply misunderstanding the phrase "animal by-products"?