for nerve impulse transmission, muscle contraction, and cell signaling. Many minerals only present in minute amounts in the body, including selenium, copper, and molybdenum, act as helpers in a wide variety of enzymatic reactions. The table below lists the AAFCO nutritional profiles for cat foods along with the roles of vitamins and minerals in cat nutrition according to the National Research Council. Many nutrients can cause a variety of deficiency symptoms in cats, and the skin is a vital organ that is susceptible to dietary changes in minerals, protein, fatty acids, and vitamins A and B. Cats show dietary inadequacies in their skin through excess or inadequate oil production, and skin toughening. This results in dandruff, redness, hair loss, greasy skin, and reduced hair growth. Arginine Cats are unusually dependent on a constant supply of the amino acid arginine, and a diet lacking arginine causes marked weight loss and can be rapidly fatal. Arginine is an essential additive in cat food because cats have low levels of the enzymes which are responsible for the synthesis of ornithine and citrulline in the small intestine (specifically, for pyrroline-5-carboxylate production). Citrulline would typically go on to the kidneys to make arginine, but because cats have a deficiency in the enzymes that make it, citrulline is not produced in adequate quantities to make arginine. Arginine is essential in the urea cycle in order to convert the toxic component ammonia into urea that can then be excreted in the urine. Because of its essential role, deficiency in arginine results in a buildup of toxic ammonia and leads to hyperammonemia. The symptoms of hyperammonemia include lethargy, vomiting, ataxia, and hyperesthesia, and can be serious enough to induce death and coma in a matter of days if a cat is being fed an arginine-free diet. These symptoms appear quickly because diets devoid in arginine will typically still contain all of the other amino acids, which will continue to be catabolized by the body, producing mass amounts of ammonia that very quickly build up with no way of being excreted. Zinc Zinc's connection to skin and coat health is due to its influence on regulating cellular metabolism. Zinc also supports proper immune function and suitable activity within the inflammatory response. Deficiencies result in disorders of the skin and poor immune functioning. When zinc is supplemented in diets, skin scaliness decreases. Dietary sources include poultry, red meat, and eggs.