ApplawsSenior Tuna Fillet & Pumpkin Recipe Mousse

A fish used mostly in cat foods, where its strong flavor is the point. Tuna is a good protein and a source of omega-3 fats. Two cautions apply to tuna fed often: it is higher in mercury than smaller fish, and cats can become fixated on it and refuse other foods. Both cautions apply to the cat eating tuna every day, and much less to tuna as one ingredient in a complete food fed in rotation.

Fish with no species stated. The maker may use whatever is available, so the fish can change between batches. Nutritionally it is a fine protein and often a source of omega-3 fats. The gap is for pets with a known fish allergy, or whose owners are trying to track which protein causes a reaction, because an unnamed ingredient makes that very hard. Named fish such as salmon or whitefish give you that information.

A vegetable used mainly as a source of soluble fiber for stool quality, and for label appeal. Amounts in a complete food are small. Not an allergen of concern and not a meaningful protein or calorie source.

A complete, highly digestible protein, which is why formulators like it. It is also a documented allergen in about 4% of dogs with food reactions. Egg allergy does not implicate chicken meat; the proteins are different. Dried egg product is the same thing with the water removed. A good ingredient for most pets and a fine-print one for the allergic few.

Oil pressed from salmon, added for the omega-3 fats EPA and DHA that support skin, coat and joints. It does the same job as generic fish oil but names its source, which helps if your pet reacts to other fish. Like all fish oils it spoils easily and needs a preservative, usually mixed tocopherols. The levels used in food are a modest supplement, well below a therapeutic dose.

The familiar white potato, used as a carbohydrate source in many grain-free foods. Potato starch binds kibble; potato protein is a concentrated plant protein that lifts the protein figure on the bag. Cooked potato is safe and well digested. Grain-free foods built on potatoes and legumes were part of the FDA's 2018 to 2022 look at diet-associated heart disease in dogs, which did not establish a cause; the agency has not asked for any to be withdrawn.

A small fruit added mostly for its association with urinary health. Cranberry compounds can make it harder for some bacteria to cling to the bladder wall in laboratory studies, but there is no good evidence that the amount in a pet food prevents or treats urinary infections. At label levels, a small amount well down the list, treat it as a minor fruit that adds a little fiber and antioxidants.