feed additives

non-nutritive substances added to feeds to improve the efficiency of feed utilization and feed acceptance or be beneficial to the health or metabolism of the animal in some way

they are substances other than nutrients or sources of nutrients

rancidity

when lipoxidase oxidizes double bonds in oil; as a result peroxides are formed and these undergo further reaction to produce toxic and foul-smelling aldehydes and ketones; aka autooxidation

antioxidants

inactivates peroxides and inhibits the chain reactions that cause rancidity to develop

ammoniation

the supplication of ammonia as a mold inhibitor; it causes the destruction of aflatoxin

non-starch polysaccharides (NSP)

polymers of starches in grains which adversely affect animal performance because its high viscosity inhibits nutrient absorption

cellulase

enzymes which digest cellulose, increasing the ability of nonruminants to utilize fibrous feeds 

phytase

organic molecules containing bound phosphorus, which is of low bioavailability to nonruminant animals

bloat

caused by the formation of a stable foam in the rumen, causing rumen gases to accumulate; foam at the base of the esophagus inhibits eructation

defaunating agents

protozoa in the rumen = K.O.

ionophores

antibiotics that inhibit bacterial growth by disrupting the normal transport of mineral ions across the cell membrane of gram-positive bacteria; results in more propionic acid

coccidiosis

a disease caused by protozoa that damage the gut lining

diethystilbestrol (DES)

a synthetic estrogen used as a feed additive for cattle but was withdrawn by the FDA in the 70s; implicated as a carcinogen

growth hormone (bST, pST)

*not* a feed additive; increases growth rate and mil production; as a protein is digested in the gut if fed and would have no biological activity

direct-fed microbials

probiotics; live microbial supplements that may beneficially affect the host animal by improving its GI microbial balance

repartitioning agents

substances that cause a change in the nutrient profile of body tissues, or "repartitioning" of nutrients from fat to protein; aka beta-agonists

zeolites

clay materials used as feed additives which have a similar effect to sarsaponins or yucca extract; binds ammonia and prevents its release into the air

xanthophyll pigments

cause the yellow color of egg yolks and the skin and shanks of broilers; carotenoid pigments similar in structure to beta carotene; no vitamin A activity and no nutritional value