"March 22, 2010: Test results are back on samples believed to be "Nutro Natural Choice Chicken Meal and Rice" cat food, and "ProPlan Beef & Barley" and "Orscheln's Oatmeal for Seniors" dog foods.
It is the view of pfpsa.org that Nutro is the most dangerous and poorly formulated pet food on the market today. Zinc was detected at levels 9 times that recommended by the National Research Council. The ratio of calcium to phosphorus isn't even close. Calcium came in at 32,000 parts per million and phosphorus at 21,000 ppm. Various sources give slightly different figures for the correct calcium to phosphorus ratio, but they are all close to 8-9 parts phosphorus for every 10 parts calcium. In addition to calcium levels being 15 times higher than needed for good health, the ratio is 6.5 parts phosphorus to 10 parts calcium.
The cat affected is about one year old, was kept indoors only, and had been eating Nutro for about five days. Blood and urine tests indicated liver and possibly kidney problems, all of which have apparently cleared up since the pet owner stopped feeding the food. In addition to the mineral screen, we also tested for aflatoxin and vomitoxin, both of which came back non detected. We are currently considering running additional tests on the food and will provide additional information if it becomes available.
It has also come to our attention that the previously reported PetAg milk replacer problems are ongoing and that the milk formula is continuing to kill baby animals. With kitten season coming up, this is a product to avoid for anyone involved in rescue work." http://www.pfpsa.org/news.html