I'm pretty sure the key is the omission of cereal/corn fillers in the recipe, but I believe there probably is another reason, too. (I'd tell if I knew.) I'd tried other foods with no fillers before, but still had the same problem, although not quite as pronounced. Maybe it's
the venison and/or the salmon, which could be more easily digested by cats than other proteins. I don't know. Whatever the reason, I buy only Taste of the Wild for my cat when I buy dry cat food. We adopted another cat from the local shelter a few years back, a then one-year old, and switched him from Iams (which the shelter uses) to Taste of the Wild. All good; five years later, he continues to flourish.
No, I'm not an employee, vendor, distributor, or any other person or entity related directly or indirectly to the manufacturer. The stuff is just really good.