TuckersSalmon-Pumpkin Raw Frozen Diet

An amino acid cats cannot make in sufficient quantity and must eat, or they develop heart disease and blindness. It is in every complete cat food by law of nutrition, not by choice. Dogs make their own, but it is added to many dog foods as a precaution after a federal investigation into diet-associated heart disease in dogs. Its presence on a dog food label is a good sign, not a warning.

A zinc source. Zinc is essential for skin, coat, immunity and wound healing, and deficiency shows up first as crusty skin. Some Arctic breeds absorb it poorly and need more. Sulfate and oxide are inorganic; proteinate or chelate is bound to protein, which brands present as better absorbed. Any of them is normal. Not an allergen.

A fat-soluble antioxidant that protects cells and the fats in the food itself. It is in nearly every complete food, both as a nutrient and, under the name mixed tocopherols, as the natural preservative that keeps fat from going rancid. Deficiency is rare in pets eating a complete diet. Nothing to worry about on a label, and a sign the maker is preserving with vitamin E rather than synthetic chemicals.

A calcium source, the same compound as limestone or chalk. Meat is low in calcium and high in phosphorus, so foods add calcium to keep the two in balance, which matters for bone and for large-breed puppies in particular. Routine and safe. Not an allergen.

A manganese source. Manganese is needed in tiny amounts for bone, cartilage and enzyme function. Sulfate is the inorganic form; proteinate is the mineral bound to protein. The choice between them is a marketing distinction more than a health one for a healthy pet. Expected, safe, not an allergen.

A copper source. Copper is essential in small amounts for blood, connective tissue and coat color. Some veterinary nutritionists have questioned whether modern dog foods carry more copper than dogs need, and a few breeds (Bedlington Terriers, Labradors among them) are prone to storing it in the liver. For most pets it is a routine additive. If your dog has a diagnosed liver condition, copper level is worth a vet conversation.

Vitamin B5 in its stable added form (the d- prefix just names the active version). It is needed to turn fats and carbohydrates into energy. Widely available in meats and grains, topped up to guarantee the level. Safe, expected, and irrelevant to allergies.

Essential for vision, skin and immune function. Cats cannot convert the plant form (beta-carotene) into vitamin A the way dogs can, so cat food must carry the preformed vitamin. It is fat-soluble and stored in the liver, so very high doses over time are harmful, which is why the amount is regulated. Normal on any complete food.

Dogs and cats cannot make useful amounts of vitamin D from sunlight, so it has to be in the food. It governs calcium and bone health. It is also one of the few vitamins where too much is dangerous: excess vitamin D has caused pet food recalls. The amount is regulated and the presence of D3 on a label is expected. What matters is that the maker gets the dose right, which is a quality-control question, not an ingredient question.

Needed for nerve function and making red blood cells. It occurs naturally only in animal tissue, so it is added to almost every food to guarantee the level. Water-soluble, so excess passes out in urine. Cats and dogs with chronic gut disease can run low even on a good diet, which is a vet conversation rather than a food choice.

An iodine source. Iodine runs the thyroid, and pets cannot get enough without it being added. Calcium iodate and potassium iodide are the common forms and do the same job. Whether dietary iodine plays a role in the overactive thyroid common in older cats has been studied without a clear answer. A normal line on any complete food.

Vitamin B2, used to turn food into energy. Present in meat and dairy but partly lost in cooking, so manufacturers top it up. Water-soluble and safe at the levels used in food. Its presence tells you the food was formulated to a complete nutrient profile, not that anything unusual is going on.