Animal Nutrition Terminology
Abomasum- The fourth stomach compartment of the ruminant; the true stomach
Ad lib- As much as desired; abbreviation for ad libitum
Additives- Materials added to food to help manufacture and preserve it and to improve its nutritive
value, palatability, and eye appeal
Alfalfa- A pasture or hay crop perennial having compound leaves with three leaflets
Alternate grazing- Hanging pastures or ranges so that the forage grows back before it is grazed again
Amylase- An enzyme secreted by the pancreas and delivered to the small intestine that aids in the
digestion of starch
Average daily gain- The calculation of an animal’s post weaning gain figured by dividing the weight
gain by the days on feed
Balanced ration- The daily allowance of livestock or fowl feed
Basal feed- A feed used primarily for its energy content
Bile- A digestive fluid produced by the liver
Bloat- An excessive gas accumulation in the rumen, abomasum, stomach, or cecum
Bolus- A rounded mass of food
Bone Meal- The product of drying and grinding animal bones, not previously steamed under
pressure, and used as a stock feed
Bunker silo- A silo for storing silage, consisting of a wide trench constructed in the side of a hill
from which surface water has been diverted
By-pass protein- A protein that is heat or chemically treated so that it does not get altered in the
ruminant stomach
By-Product- A product of significantly less value than the major product
Carbohydrate- Any of certain organic chemical compounds of carbon, hydrogen, and oxygen,
which include sugars and starches
Cecum- The proximal part of the large intestine that forms a pouch
Cholesterol- One type of lipid that circulates in the blood; it plays an important role in the
synthesis of bile, sex hormones and vitamin D
Chop- Animal feed of coarsely crushed or finely ground cereal grains
Chyle- A milky fluid consisting of lymph and triglyceride from the digestion of food
Chyme- A semi-fluid, creamy substance resulting from the digestion of food by gastric juice
Cloaca- A common passageway for fecal, urinary, and reproductive systems in birds
Colic- Severe abdominal pain; technically means pertaining to the colon
Colon- The part of the large intestine located between the cecum and rectum
Colostrum- The first milk-like substance produced by the female after parturition; it is thick, yellow
and high in protein and antibodies
Complete ration- A single feed that fulfills all of the nutritional requirements of an animal except for
water
Concentrate ratio- The amount of concentrates in comparison to the amount of other feeds fed
Concentrate- A type of feed that is high in total digestible nutrients and low in fiber (high energy
feed like grain)
Conformation- The shape and body type of an animal
Constipation- A condition of prolonged gastrointestinal transit time, making the stool hard, dry
and difficult to pass
Continuous grazing- Grazing for the entire grazing season
Coprophagia- The ingestion of fecal material; eating stool
Corn-fed- Designating an animal or fowl fattened on corn prior to marketing
Cottonseed- The seed of cotton after the lint has been removed. It is a source of cottonseed
oil, the residue being used as a stock feed
Creep feed- A high energy feed that is fed to young animals in special feed devices so that adult
animals cannot gain access to the feed
Crop- A product of a harvest obtained by labor, from natural production or wild growth
Crop pasture- A sown crop that is normally harvested but may be used for pasture if necessary, as
oats, wheat, soybeans, etc
Crude fiber- The parts of feeds containing the cellulose, lignin, and other structural carbohydrates
as determined by the proximate analysis
Crude protein- A measure or estimate of the total protein in a feed determined by multiplying
the total nitrogen content by 6.25
Crumbles- Crushed pellets of feed
Cud- Regurgitated food particles, fiber, rumen fluid, and rumen microorganisms by ruminants
Cud chewer- A ruminant
Cured forage- Dry range grasses, harvested or standing, slightly weathered, nutritious, and palatable
stock feed
Defecation- Movements of the bowels
Dehydration- A condition of excessive loss of body water or fluid
Diarrhea- Abnormal frequency and liquidity of fecal material
Diet- The type and amount of food and drink habitually ingested by a person or an animal
Dietary fiber- The generic name for plant materials that are resistant to the action of normal
digestive enzymes
Digestible energy- The proportion of energy in a feed that can be digested and absorbed by an
animal
Digestible nonnitrogenous nutrient- The total digestible nutrients less the digestible protein in a
foodstuff
Digestible nutrient- That portion of a nutrient that can be digested and absorbed into a human or an
animal body
Digestible protein- The proportion of protein in a feed that can be digested and absorbed by an
animal. Usually 50 to 80 percent of crude protein
Digestion- The process of breaking down foods into nutrients that the body can use
Digestive tract- The mouth, esophagus, digestive organs, stomach or stomachs, crop, gizzard, and
the small and large intestines and anus
Displaced abomasum- A disease of ruminants in which the abomasum dilates and migrates either to
the left or right of its normal position
Dry- To cause a pregnant cow to stop giving milk shortly before she delivers her calf
Dry matter- The total amount of matter, as in a feed, less the moisture it contains
Duodenum- The proximal portion of the small intestine; located between the pylorus and jejunum
Emaciation- Marked wasting or excessive leanness
Emulsification- The breakdown of large fat globules into smaller parts
Enrich- To add a substance or vitamin to food products
Epiglottis- The lid-like cartilage covering the larynx
Eructation- Belching or raising gas orally from the stomach
Esophagus- A collapsible tube that leads from the oral cavity to the stomach
Essential amino acid- Any of the amino acids that cannot be synthesized in the body from other
amino acids or substances or that cannot be made in sufficient quantities for the body’s use
Fat- The tissues of an animal that bear an oily or greasy substance
Fattening- The feeding of animals or fowls so that they put on fat
Feces- Solid body wastes expelled through the rectum
Feed additives- Material added to livestock feed that is not a nutrient but enhances the growth
efficiency of the animal
Feed bunk- A forage and grain feeding station
Feed conversion ratio- The rate at which an animal converts feed to meat
Feed energy utilization- The percentage of energy obtained from a feed that is used for an animal’s
bodily functions
Feed out- To prepare animals for market by fattening
Feedlot- A confined area where an animal is fed until it is slaughtered
Feedstuff- One of, or a mixture of, the substances that form the nutrients and are not normally fed
by itself but is mixed with other feedstuffs to formulate a feed
Filler- The nonessential matter in a manufactured or mixed feed
Finishing- The increased feeding of an animal just prior to slaughter
Fitting cow ration- Ration fed to cows that are being prepared for exhibition, sale or calving
Flatulence- Excessive gas formation in the gastrointestinal tract
Folic acid- A B vitamin found in the leaves of leguminous and other plants, in yeast, liver meal,
and wheat.
Forage- That portion of the feed for animals that is secured largely from leaves and stalks of plants,
such as the grasses and legumes used as hay
Forage crops- Those plants or parts of plants that are used for feed before maturing or developing
seeds
Forage feeds- Bulky type feeds composed largely of pasture grasses, hays, silage
Forage legumes- Any of the legume plants that are grown or used largely as forage for livestock,
such as alfalfa and clover
Fortified- Designating a product to which amounts of a vitamin, as vitamin A or vitamin D have
been added
Free-choice feeding- A type of feeding routine whereby feed, water, salt, etc., are provided in
unlimited quantities and an animal is left to regulate its own intake
Free-ranging- Allowing animals, especially poultry, to roam freely and eat as they wish without any
sort of confinement
Fresh manure- recently excreted animal dung whose direct contact can be harmful to plant tissues
because of rapid chemical and fermentive changes that take place
Gastric- Refers to the stomach
Gastrointestinal- The digestive tract
Gizzard- The muscular posterior stomach in birds
Grain-fed- Designating animals, such as cattle, which are being or have been fattened for market
largely by the use of grain feeds
Grass- Cattle marketed directly off grass pastures and not grain-fed
Grazing- Feeding available to animals on ranges and pastures
Green chop- Green forage that is cut with a field chopper and hauled to lots or barns for livestock
feed in lieu of pasturing
Guaranteed analysis- In feed label or tags, a listing of certain nutrients, usually crude protein,
crude fiber, fat, and ash, guaranteeing a minimum or maximum percentage of each in the
feed
Hair ball- The hair an animal has swallowed that has gathered in the stomach in the form of a ball;
common in the stomach of cats and in the rumen of ruminants
Hand feeding- A type of feeding routine whereby an animal is fed measured amounts of food, water,
salt, etc. at fixed intervals
Hard feeder- An animal that stays in a thin condition even though well fed
Hardware disease- A condition found in ruminants in which metal objects, such as wire, nails and
screws, are swallowed with feed, and because of their weight, lodge in the reticulum
Hay- Any leafy plant material, usually clover, fine-stemmed grasses and sedges, alfalfa, and other
legumes, that has been cut and dried principally for livestock feed
Hay belly- A term applied to animals having a distended barrel due to excessive feeding of bulky
rations, such as hay, straw or grass
Haylage- Forage that could have been cut for hay but is stored with a higher moisture content than
hay, and with less moisture than silage
Herbivore- An animal that is able to sustain life by only eating plants
Impaction- An obstruction of an area usually with feed that is too dry
Inert ingredient- A substance in a feed, pesticide, etc. that does not act as a feed, pesticide, etc.
Ingest- To eat, or take in food for digestion by way of the mouth
Intestine- The part of the digestive tract between the stomach and anus
Iron- A metallic element that is an essential constituent of blood hemoglobin where it functions to
transport oxygen
Jejunum- The middle portion of the small intestine; located between the duodenum and ileum
Keratin- A fibrous protein that composes hair, epidermis, and nails
Ketone- A by-product of fat metabolism
Lactation- The process of forming and secreting milk
Lactose-A white crystalline disaccharide made from whey and used in pharmaceuticals, bakery
products, and confections
Laxative- A mild medicine used to relieve constipation
Lean to fat ratio- The amount of lean meat in a carcass compared to the amount of fat
Legume- Roughage plants that have nitrogen-fixing nodules on their roots; e.g. alfalfa and clover
Light feeder- An animal that is being fed for maintenance and normal growth but not for quick
finish or fattening
Lipase- A fat-digesting enzyme
Live weight- The gross weight of a live animal as compared with the dressed weight after slaughter
Liver- Secretes bile and performs certain metabolic functions
Loose hay- Hay stored in the hay mow or stack without chopping, baling, or compressing
Maintenance ration- The amount of feed needed to support an animal when it is doing no work,
yielding no product, and gaining no weight
Malabsorption- The impaired uptake of nutrients from the intestines
Malnutrition- An unhealthy condition resulting from either poor feed or lack of feed
Mash- A ground feed or cereals and malt
Masticate- To chew; to prepare food for swallowing and digestion
Meat- The edible flesh of an animal
Metabolism- The processes involved in the body’s use of nutrients
Metabolizable energy- The total amount of energy in feed less the losses in feces
Milk-fed- Designating animals largely on dairy products
Milk replacer- A powder that, when mixed with water, is fed to young animals as the milk portion of
their diet
Mineral- A chemical compound or elements of inorganic origin
Mineral mixture- Any feed containing salt, limestone, phosphates, minor elements
Monogastric- An animal with one stomach compartments
Niacin- A vitamin of the B-complex group
Night stool- A rabbit’s nocturnal feces that are looser than normal and contain vitamins and
nutrients that the rabbit consumes
Nitrogen-free extract- The portion of a feed made up primarily of starches and sugars
Nonessential amino acid- Amino acids that can be synthesized by the animal’s body
Nutrient- A substance that favorably affects the nutritive processes of the body; a food
Nutriment- Nourishment; nutritious substances; food
Nutrition- The sum of the processes by which an organism utilizes the chemical components of
food through metabolism to maintain the structural and biochemical integrity of its cells
Nutritive additive- An additive that has some food value such as a vitamin or mineral
Nutritive ratio- In animal feeds, the ratio or proportion between the digestible protein and the
digestible nonnitrogenous nutrients found by adding the digestible carbohydrates plus the
digestible fat multiplied by 2.25 and dividing the sum by the digestible protein
Nutritive value- The relative capacity of a given feed to furnish nutrition for livestock
Obesity- Excessive fat accumulation in the body
Omasum- The third compartment of the ruminant stomach. Contains a mass of suspended, parallel,
rough-surfaced leaves that grind ingesta to a fine consistency
Omnivore- An animal that sustains life by eating plant and animal products
Palatability- The degree to which a feed is liked or acceptable to an animal
Pancreatic juice- A secretion by the pancreas containing ferments that contribute to digestion of
foods
Pasture- An area for grazing animals
Pasture rotation- The practice of moving the herd from one field to another after a few days of
intensive pasturing
Paunch- Another name for the rumen
Pelleted feed- A pill-like or cubical type of animal feed made by forcing the loose, bulky, or dusty
feeds into small, uniform pellets by the use of grinding, molding, and compressing
machinery
Pelleted hay- Hay that has been highly compressed by passing through a pelleting machine
Pepsin- A digestive enzyme secreted by glands in the stomach
Peptide- A compound made up of a series of amino acids
Protein- Any of a large number of complex, organic compounds of amino acids that have a high
molecular weight and are essential to all living organisms
Proventriculus- Inflammation of the glandular stomach that often occurs in growing chicks reared in
confinement and occasionally in adult fowls
Rate of growth- The rate at which a young animal increases weight and height
Ration- The amount of consumed by an animal in a 24-hour period
Ration of maintenance- The feed necessary to maintain the body of an animal
Rectum- The distal portion of the large intestine
Regurgitate- The return of swallowed food into the oral cavity
Reticulum- The most cranial compartment of the ruminant forestomach. Has a honeycomb-textured
lining
Roughage- A type of feed that is high in fiber and low in total digestible nutrients (examples: pasture
and hay)
Rumen- The largest compartment that serves as a fermentation vat of the ruminant fore-stomach,
also called the paunch
Rumen magnet- A smooth oblong magnet that is placed in the rumen to collect small metal objects
that are swallowed by the animal during grazing
Ruminant- A cud-chewing animal that has a fore-stomach that allows for fermentation of ingesta
Rumination- A series of digestive functions in ruminants that includes regurgitation, remastication,
and re-swallowing of regurgitated food
Saliva- A secretion from glands in the oral cavity that moistens food, aids in bolus formation, and
contains small amounts of digestive enzymes
Salt- Sodium chloride, a white crystalline compound occurring abundantly in nature as a solid or in
solution
Scour- To cleanse the bowels of an animal by purging
Scratch feed- The grain part of a ration for poultry that consists of cracked or whole grain or a
mixture of such grains
Secretin- A hormone produced in the intestine (duodenum) that controls the secretion of the
pancreatic juices or enzymes
Silage- A type of roughage feed that is produced by fermenting chopped corn, grasses, or plant parts
under specific moisture conditions to ensure preservation of feed without spoilage
Silo- A pit, trench, aboveground horizontal container, or vertical cylindrical structure of relatively
air-tight construction into which green chops, such as corn, grass, legumes, or small grain
and other feeds are placed and converted into silage for later use as a livestock feedstuff
Spoilage- Hay or forage that has been improperly cured or stored
Starter- The first food provided for young animals
Stomach- The digestive pouch at the distal end of the esophagus that mechanically and chemically
breaks down food
Stool- Fecal material from the digestive tract
Supplement- A feed or feed mixture that is relatively richer in a specific nutrient than the basic feed
ingredients in the ration to which it is added
Sweetfeed- Food that consists of grains and pellets mixed with molasses to increase palatability
Taste- The flavor of a product as determined by placing the substance in the mouth
Thiamin- A member of the vitamin B complex
Total digestible nutrients- All the nutrients consumed by an animal that are digested and used;
generally applied to proteins, carbohydrates and fats
Trace- To follow the course of nutrient elements in plants or animals
Triglyceride- One type of lipid that circulates in the blood
Trypsin- One of the principal proteolytic enzymes of the pancreatic secretion in people and animals
Turgor- The degree of fullness or rigidity due to fluid content
Ungulate- Animals with hooves
Urea- The end product of protein metabolism found in urine, blood, and lymph
Vegetarian- An herbivorous animal or person
Vent- The opening of the cloaca; the anus of a bird
Ventriculus- The muscular stomach of birds; also called the gizzard
Vigor- Healthy growth; having high energy
Vitamin- An organic substance, classified as either fat or water soluble, that performs specific and
necessary functions in relatively small concentrations in an organism
Watering- Furnishing water for the consumption by animals
Wean- To make a young animal cease to depend on its mother’s milk
Zinc- A metallic chemical element; one of the micronutrient elements in soils, essential for both
plant and animal growth