Badlands RanchSuper20

A plant source of omega-3 fat (alpha-linolenic acid) and fiber, used in about a third of dog foods for coat and stool quality. Dogs and cats convert plant omega-3 to the useful forms inefficiently, so fish oil does the job better. Flax is not a documented common allergen, though some pets tolerate it poorly, most often as loose stool. Fine in a food; not a reason to prefer it over one using fish oil.

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 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.