[kjc]

Choline chloride is an organic compound and a quaternary ammonium salt. Choline chloride is mass produced and is an important additive in feed especially for chicken where it accelerates growth.

Methionine is one of the 10-plus essential amino acids that are required by both the cat and dog... Crystalline DL-methionine has become the standard of the petfood industry... Dietary methionine
Common petfood ingredients rich in methionine include animal proteins such as meat and poultry and their associated protein meals, egg products, marine proteins such as fish and fish meals, corn co-products such as corn gluten meal and brewers dried yeast. Many diets that contain these ingredients are adequate in methionine and do not require any supplementation. For diets that contain minimal amounts of meat proteins, are heavily weighted to vegetable proteins like soy or are low calorie foods diluted with inert ingredients such as cereals and cellulose, there may be a need for supplemental methionine. (http://www.petfoodindustry.com)

Magnesium oxide, or magnesia, is a white solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide).
In medicine, magnesium oxide is used for relief for heartburn and sore stomach, as an antacid, magnesium supplement, and as a short-term laxative. It is also used to improve symptoms of indigestion.

Lecithin is regarded as a well-tolerated and non-toxic surfactant. It is approved by the United States Food and Drug Administration for human consumption with the status "Generally Recognized As Safe." Lecithin is an integral part of cell membranes, and can be totally metabolized, so it is virtually non-toxic to humans. Other emulsifiers can only be excreted via the kidneys.

Taurine, or 2-aminoethanesulfonic acid, is an organic acid. It is also a major constituent of bile and can be found in the lower intestine and in small amounts in the tissues of many animals, including humans.[1][2] Taurine is a derivative of the sulfur-containing (sulfhydryl) amino acid, cysteine. Taurine is one of the few known naturally occurring sulfonic acids.

Zinc sulfate (ZnSO4) is a colorless crystalline, water-soluble chemical compound. The hydrated form, ZnSO4·7H2O, the mineral goslarite, was historically known as "white vitriol" and can be prepared by reacting zinc with aqueous sulfuric acid. It may also be prepared by adding solid zinc to a copper(II) sulfate solution.
Zn + CuSO4 → ZnSO4 + CuIt is used to supply zinc in animal feeds, fertilizers, and agricultural sprays.

Iron(II) sulfate (Iron(II) sulphate) or ferrous sulfate (ferrous sulphate) is the chemical compound with the formula (FeSO4), known since ancient times as copperas. It is most commonly encountered as the blue-green heptahydrate. ... ferrous sulfate is used to fortify foods and to treat iron-deficiency anemia. Constipation is frequent and uncomfortable side effects associated with the administration of oral iron supplements. Stool softeners often are prescribed to prevent constipation.