ascorbic acid/ascorbyl palmitate:
These are both forms of vitamin C. Ascorbyl palmitate is sometimes used in pet foods as part of a natural preservative system, because by itself it is a weak preservative.

beta-carotene:
Beta-Carotene is an antioxidant. Research has shown that death cell occurs due to the process of oxidation, which is caused by what are called "free radicals". Antioxidants such as beta-carotene neutralize these free radicals and the oxidation process is stopped. Beta-Carotene may also protect against certain cancers, cataracts and heart disease. Carrots and sweet potatoes are good source of beta-carotene.

biotin:
This B-vitamin is included in most diets for most pets. It is found in the intestinal tract and helps prevent dermatitis. It is essential for normal metabolism of fat and protein.

calcium carbonate:
Calcium carbonate is a mineral used to provide calcium.

calcium iodate/potassium iodate:
Two sources of the essential trace mineral iodine, both of which are highly available.

calcium pantothenate/pantothenic acid:
These two compounds are often used as sources of the B-vitamin pantothenic acid. Calcium pantothenate is usually the preferred form because of its stability. Calcium pantothenate mainly converts fat into energy.

choline chloride:
A source of the nutrient choline. Choline helps regulate body acid balance and helps the liver clean waste from the body.

cobalt carbonate - B12:
Cobalt carbonate is a source of cobalt. When consumed the microorganisms in the gastrointestinal tract use the cobalt to make vitamin B12.

copper proteinate/copper sulfate:
Two compounds which are used as a source of copper. The copper from copper proteinate is highly available while the copper from copper sulfate is less so. A trace mineral found in all body tissues. It works in respiration, synthesis of hemoglobin and production of collagen. It is also an antioxidant and helps prevent oxidation of fatty acids.

dicalcium phosphate:
A mineral supplement which contains 20% calcium and 18% phosphorus. The phosphorus is essentially 100% available.

ferrous (iron) proteinate/ferrous sulfate:
Two compounds which are used as a source of iron. The iron from ferrous proteinate is highly available while the iron from ferrous sulfate is less so. It provides oxygen to blood and helps digestion of fatty acids.

folic acid:
Folic acid is another B-vitamin that is added to most pet foods. It helps form red blood cells and break down amino acids.

manganese proteinate/manganese sulfate/manganous oxide:
Three compounds which are used as a source of manganese. Manganese proteinate is an antioxidant. It slows down process of aging, activates many enzymes and helps utilize fatty acids.

niacin/niacinamide:
While the B-vitamin niacin is present at high levels in most grains, unless properly treated, most of the niacin in these ingredients is in a bound form and hence unavailable to the pet. For this reason most manufacturers supplement their diets with one of these two forms of niacin. It helps process protein, carbohydrates, and fat and promotes healthy nervous and brain function.

potassium chloride:
A potassium supplement typically found in pet food. It contains 40% potassium and 60% chloride. It is important in helping the pet maintain proper acid-base balance.

pyridoxine hydrochloride:
Pyridoxine hydrochloride is the most common form used when supplementing pet foods with the B-vitamin pyridoxine. Pyridoxine is very important in helping the pet metabolize protein.

riboflavin:
Riboflavin is used to supply the diet with vitamin-B complex. It helps promote growth and helps assimilation of carbohydrates and amino acids.

sodium selenite:
A source of the trace mineral selenium. Since animals require only about 0.1 parts per million of selenium, sodium selenite does not contribute any significant amounts of sodium. Helps regulate the body's water balance.

thiamin mononitrate/thiamin hydrochloride:
These two compounds are both forms of thiamin or vitamin B-1. The mononitrate form is typically more stable than the hydrochloride form. Thiamin is easily destroyed by high heat, so most dry foods and all canned foods should be supplemented with additional thiamin.

tricalcium phosphate:
A mineral supplement which contains 38% calcium and 20% phosphorus. The phosphorus is essentially 100% available.

vitamin A, vitamin D, and vitamin E
These supplements are added to almost all pet foods as a vitamin source. Vitamin A is sometimes labeled as vitamin A-acetate, vitamin D as cholecalciferol, and vitamin E as d-alpha-Tocopherol acetate . All of these fat soluble vitamins are required in the diet, although diets containing liver are often not supplemented with vitamin A, because liver is an excellent source of vitamin A.

vitamin B-12 supplement/cyanocobalamin:
Although usually referred to on labels as vitamin B-12, this B-vitamin is sometimes called by its chemical name cyanocobalamin. Vitamin B-12 is only found in animal based ingredients, and most animals obtain enough vitamin B-12 from the microbes in their gut. Animals on antibiotics may require supplemental vitamin B-12.

zinc proteinate/zinc sulfate/zinc oxide:
Three compounds which are used as a source of zinc. The zinc from zinc proteinate is highly available and is important for proper maintenance of hair, skin, bones, muscles and blood. It also helps digestion and reproduction.