MaxboneDog Food Freeze Dried Duck grain-free gluten-free

A poultry protein, fattier and richer in iron than chicken. As with other fresh meats, the wet weight pushes it up the list; duck meal is the dried form. Duck is a different family of bird from chicken and turkey, which is why it is used as a novel protein, though pets that react to chicken sometimes react to duck as well.

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.

Broccoli florets or stems, dried and added in small amounts for fiber, vitamins and antioxidants. It is safe for dogs and cats at food levels. Very large quantities contain compounds that can irritate the gut, which matters for a dog raiding the vegetable drawer. A fraction of a percent in kibble is nowhere near that, and it does not change the food's nutrition in any measurable way.

A fruit added for fiber, a little natural sweetness and antioxidants. Apple flesh is safe for dogs and cats. The seeds contain a trace of a cyanide-forming compound, which matters for a dog eating whole apples and is far below any concern at the amounts of pomace or dried apple in a food. Apple pomace is what remains after juicing and is mostly fiber. In either form it appears in small amounts and does not change the nutrition of the food in a meaningful way.

A root vegetable used as a carbohydrate source, especially in grain-free foods. It supplies energy, fiber and beta carotene and is well digested by dogs. There is no good evidence it beats rice or oats nutritionally, though it is a reasonable choice for pets that do poorly on grains. Like any starch, a food that lists it high is a starch-heavy food.

A fruit added in small amounts for antioxidants and a bit of fiber. Blueberries are safe for dogs and cats, and the pigments that color them are the same ones linked to antioxidant activity in people. In a complete food they appear well down the list in small amounts, so they are a modest extra and should not decide which bag you buy.

A vegetable that contributes a little fiber and beta-carotene and a lot of label appeal. In dry food it is usually present in small amounts well down the list. It is not an allergen of concern and not a meaningful protein or calorie source. Fine to see; not a reason to choose one food over another.

Oil pressed from whole fish, usually menhaden, herring or sardine, added as the source of the omega-3 fats EPA and DHA. Those fats support skin, coat, joints and brain development, and a food that names fish oil is delivering them in the form pets use directly. It goes rancid quickly, so look for a preservative named alongside it, usually mixed tocopherols. The species is rarely stated, which matters only if your pet reacts to fish.