Taste cats prefer - Nutrition Veterinarians recommend. Iams Canned Cat Foods are slow-cooked with real catfish and broth to provide the taste cats prefer. Each serving is completes and balanced for adult cats with vitamins and minerals for the nutrition veterinarians recommend. Low in Magnesium. Animal feeding tests using AAFCO procedures substantiate that Iams Catfish Formula Cat Food provides complete and balanced nutrition for maintenance.