Tiki PetsTopper: Chicken & Duck Liver

The most common protein in pet food, and for dogs one of the most common food allergens, with beef and dairy. If chicken is what your pet reacts to, it hides everywhere: chicken fat, chicken broth, chicken meal, natural flavor. On a label, chicken listed first is weighed with its water still in, so a food leading with fresh chicken often has less chicken protein than one leading with chicken meal. Neither is better; they are different measures.

Organ meat from the named animal, or unnamed when the label just says liver. Liver is one of the most nutrient-dense foods there is, rich in vitamin A, copper, iron and the B group, and most pets love the taste, which is why it is used both as an ingredient and as a flavor coating. For allergies, the species is what matters, and beef liver is beef. Unnamed liver can come from any species and may vary by batch.

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.

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.

A spice added for color and for its curcumin, a compound studied for anti-inflammatory effects. In people and lab animals curcumin is poorly absorbed unless paired with black pepper or fat, and the amounts in a pet food are far below those used in supplement studies. It is safe and gives kibble a warm color, which is most of what it is doing here; the joint and anti-inflammatory claims rest on doses far higher than a food provides.

An extract added in tiny amounts for its antioxidant compounds, and in some dental treats for breath. The caffeine content is the only real question, since caffeine is toxic to pets in quantity; the extract is usually decaffeinated or used in amounts too small to matter. There is no evidence the levels in a pet food produce any health effect. It is a marketing ingredient, safe at food levels.