Just as oxidation can cause rust and deterioration in metals, a similar type of oxidation occurs in feeds and feedstuffs, resulting in rancidity of fats, destruction of vitamins A, D, and E, pigmenters (carotenoids) and amino acids with resultant lowered biological energy values for the diet. If this destruction is allowed to proceed unchecked in a feed, or even in a single ingredient, a lowered feed consumption may result in disastrous nutrient deficiencies. Researchers in a number of fields have been studying the various problems resulting from uncontrolled oxidation and have been developing ways of bringing these oxidation processes under control. It is noted that oxidative rancidity or lipid peroxidation, as contrasted with hydrolytic rancidity, results in a serious decrease in the energy value of a fat or oil.
Undesirable oxidation in feeds may be combatted in several ways. Care should be used to make certain that the ingredients included in the feeds provide adequate margins of safety of vitamins A, E, and other natural antioxidants; e.g., lecithin. The use of unstable fats and oils or other pro-oxidants in the feed should be minimized whenever possible.