Vocab Flashcards
Abomasum
the fourth compartment of a ruminant’s stomach, which has functions similar to that of the glandular stomach of non-ruminants
Absorption
the movement of nutrients (or other compounds) from the digestive tract (or through other tissues such as the skin) into the blood and/or lymph system
Acetic acid (acetate)
one of the volatile fatty acids commonly found in silage, rumen contents, and vinegar as a result of microbial fermentation
Additive
an ingredient or combination of ingredients added in small quantities to a basic feed mix for the purpose of fortifying the basic mix with trace nutrients, medicines, or drugs
ADF
acid detergent fiber; the fraction of a feedstuff not soluble by acid detergent; roughly comparable to crude fiber plus lignin
Ad libitum
unrestricted consumption of feed or water
Alimentary
having to do with feed or water
Alimentary tract
a term synonymous with the digestive or gastrointestinal tract
Amino acids
the simplest organic structure of which proteins are formed; all have the common property of containing a carboxyl group and an amino group on the adjacent carbon atom
Amino acids, essential
amino acids that must be present in the diet; they include arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine
Amino acids, nonessential
amino acids that are found in common proteins but may be partly or completely synthesized by the animal’s tissues; they include alanine, aspartic acid, citrulline, cysteine, glutamic acid, glycine, hydroxyproline, proline, serine, and tyrosine
Amylase
any of several enzymes that can hydrolyze starch to maltose or glucose
Antibiotic
a substance produced by one microorganism that has an inhibitory effect on another organism
Antioxidant
a substance that inhibits the oxidation of other compounds
Antivitamin
a substance that interferes with the synthesis or metabolism of a vitamin
Anus
the distal opening of the gastrointestinal tract
As fed
as commonly used by the animal
Ash
the residue remaining after complete incineration of 500°C to 600˚C of a feed or animal tissue. Only metallic oxides or contaminants such as soil should remain
Balanced ration (or diet)
a combination of feeds that provides the essential nutrients in the required proportions
Basal metabolic rate
the basal metabolism expressed in kilocalories per unit of body size; the heat production of an animal during physical, digestive, and emotional rest
Beriberi
a deficiency (acute) of thiamine, one of the B-complex vitamins
Bile
a secretion from the liver containing metabolites such as cholesterol and bile acids, which aid in the digestion of fats
Biological value
the efficiency with which a protein furnishes the required amounts of essential amino acids; usually expressed as a percentage
Bomb calorimeter
an instrument used for measuring the gross energy (GE) content of any material that will burn
Butyric acid (butyrate)
one of the volatile fatty acids commonly found in rumen contents and in poor-quality silages
Calorie
the amount of energy required to raise the temperature of water from 14.5°C to 15.5˚C
Calorimeter
the equipment used to measure the heat generated in a system
Carbohydrate
organic substance containing C, H, and O, with the H and O present in the same proportions as in water. Many different kinds are found in plant tissues; some are vital to animal metabolism
Carotene
a yellow organic compound that is the precursor of vitamin A
Catalyst
a substance that changes the rate of a chemical but is not itself used up in the reaction The use of platinum in hydrogenating unsaturated fats is an example
Cecum (caecum)
a blind pouch located at the junction of the small intestine with the colon (the appendix in humans); it is part of the large intestine
Cellulose
a polymer of glucose molecules that is resistant to hydrolysis by most digestive enzymes (except some produced by microorganisms)
Cholesterol
the most common member of the sterol group found in blood and many other animal tissues; not present in any plant tissues
Cholic acid
a family of steroids comprising the bile acids; they are derived from metabolism of cholesterol by the liver
Chyme
a semiliquid material produced by the action of gastric juice on ingested food
Chymotrypsin
a proteolytic digestive enzyme secreted by the pancreas
Coenzyme
an organic molecule required by some enzymes to produce enzymatic activity; vitamin coenzymes include niacin, pyridoxine, thiamine, riboflavin, pantothenic acid, and folic acid
Colon
part of the large intestine; divided into the transverse, descending, and ascending segments
Complete feed
a single mixture used as the only source of food for an animal
Concentrate
any feed containing relatively low levels of fiber (20% or less) and with 60% or more total digestible nutrients (TDN). Opposite of roughage; or a concentrated source of one or more nutrients used to supplement a feed mix
Crude fat
the portion of feed (or other material) that is soluble in ether; also referred to as ether extracts
Crude fiber
the fibrous, less digestible portion of a feed
Crude protein
total ammoniacal nitrogen x 6.25, based on the fact that feed protein, on the average, contains 16% nitrogen; many nonprotein nitrogen compounds may be included
Cud
the solid mass of ingesta regurgitated and remasticated in the process of rumination (synonymous with bolus)
Deamination
removal of the amino group from an amino acid
Defluorination
having the fluorine content reduced to a level that is nontoxic under normal feed use
Degradation
conversion of a chemical compound to one that is less complex
Dextrin
an intermediate polysaccharide product obtained during starch hydrolysis
Diet
a regulated selection or mixture of feedstuffs provided on a continuous or prescribed schedule
Digestibility, apparent
the percentage of a feed or nutrient that is apparently absorbed from the gastrointestinal tract as indicated by intake minus fecal output; it differs from true digestibility in that feces contain substances derived from the body, many microbial products, and various secretions, as well as undigested food
Digestibility, true
the percentage of a feed nutrient actually absorbed from the gastrointestinal tract
Digestion
the process involved in preparing food for absorption
Disaccharide
any of several dimers (contains two simple sugars); for example, sucrose (common table sugar) yields glucose and fructose
Dispensable amino acid
synonymous with nonessential amino acid
Dry matter
the portion of a feed or tissue remaining after water is removed by drying in an oven
Duodenum
the first segment of the small intestine
Emulsifier
a material capable of causing fat or oils to remain in liquid suspension
Emulsify
to disperse small drops of liquid into another liquid
Enzyme
a protein formed in plant or animal cells that acts as an organic catalyst
Ergosterol
a sterol found chiefly in plant tissues; on exposure to ultraviolet irradiation, it becomes vitamin D
Eructation
belching of gas by ruminants as a normal means of expelling gases of fermentation
Esophagus
the passageway (tube) from the mouth to the stomach
Excreta
the products of excretion, primarily feces and urine
Fat soluble
soluble in fats and fat solvents but generally not soluble in water
Feed
any material used as food by an animal; same as feedstuff
Fermentation
chemical changes brought about by various microorganisms
Fibrous
high in content of cellulous and/or lignin (or in cell walls of NDF; neutral detergent fiber)
Fistula
an abnormal passage from some part of the body to another part or the exterior, sometimes surgically inserted
Forage
crops used as pasture, hay, haylage, silage, or green chop for feeding animals
Fructose
a six-carbon monosaccharide; one of the components of sucrose
Galactose
a six-carbon monosaccharide; one of the components of lactose
Gallbladder
a membranous sac attached to the liver of farm livestock (except the horse) in which bile is stored
Gastric juice
a clear liquid secreted by the wall of the stomach; it contains HCl and the enzymes rennin, pepsin, and gastric lipase
Gastrointestinal
pertaining to the stomach and intestine
Glucose
a six-carbon monosaccharide found in the blood and as a component of sucrose and maltose and other sugars
Glycerol
an alcohol containing three carbons and three hydroxyl groups; a component of fat
Glycogen
a polysaccharide found in the liver and muscles as a reserve form of quickly available energy
Goiter
an enlargement of the thyroid gland sometimes caused by an iodine deficiency
Gross energy
the total heat of combustible material burned in a bomb calorimeter
Heat increment
the heat that is unavoidably produced by an animal incidental with nutrient digestion and utilization
Hydrogenation
the chemical addition of hydrogen to any unsaturated compound (double bond), often to fatty acids
Hydrolysis
the chemical process whereby a compound is split into simpler units with the uptake of water
Hypervitaminosis
an abnormal condition resulting from the intake of (or treatment with) an excess of one or more vitamins
Ileum
the third section of the small intestine
Ingest
to take into the mouth
Insulin
a hormone secreted by the pancreas into the blood; it is involved in regulation and utilization of blood glucose
Intestinal tract
the small and large intestines
Jejunum
the middle portion of the small intestine
Kcal
an abbreviation for kilocalorie; 1,000 calories
Ketone
a group of chemicals that includes acetone, acetoacetate acid, and betahydroxy butyric acid; they are produced in excess when carbohydrate metabolism is low and fat is being metabolized for energy
Lactase
an enzyme present in the intestinal juice that acts on lactose to produce glucose and galactose
Lactic acid
an organic acid commonly found in sour milk and silage; it is important in the body during anaerobic glycolysis
Lignin
a biologically unavailable polymer that is a major structural component of the cell wall of plants
Linoleic acid
an 18-carbon unsaturated fatty acid; one of the essential fatty acids; it occurs widely in plant glycerides
Lipase
a fat-splitting enzyme; different lipases are produced by the stomach and pancreas
Lipids
substances that are diverse in chemical nature but are soluble in fat solvents
Lymph
the slightly yellow transparent fluid occupying the lymphatic channels of the body
Macrominerals
the major minerals (in terms of the amounts required in the diet or found in body tissues): calcium (Ca), chlorine (Cl), magnesium (Mg), phosphorous (P), potassium (K), sodium (Na), and sulfur (S).
Malnutrition
an overall term for poor nourishment
Maltase
an enzyme that splits maltose to produce two molecules of glucose
Megacalorie (Mcal)
1,000 kcal or 1 million calories; synonymous with therm
Metabolic size
the body weight raised to the ¾ power (W0.75); a means of relating body weight to heat production of an animal
Metabolism
the sum of all the physical and chemical processes taking place in a living organism
Metabolite
any compound produced during metabolism
Metabolizable energy (ME)
digestible energy minus the energy of the urine and combustible gases from the gastrointestinal tract (primarily methane)
Methane
a major product of anaerobic fermentation of carbohydrates; found in the rumen
Microminerals
the trace elements required by animal tissues that must be in the diet: cobalt (Co), copper (Cu), chromium (Cr), fluorine (F), iodine (I), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), silicon (Si), vanadium (V), and zinc (Zn). Synonymous with trace minerals.
Minerals
as applied to animal nutrition, elements that are essential to the plant or animal and that are found in its tissues
Miscible
capable of being mixed easily with another substance
Monogastric
the simple stomach; often applied to nonruminant animals, but technically a misnomer because ruminants have only one stomach with four compartments
Monosaccharide
any one of several simple sugars
Mucosa
the membranes that line the passages and cavities of the body
Mucus
a slimy liquid secreted by the mucous glands and membranes
NDF
neutral detergent fiber; the fraction containing mostly cell wall constituents of low biological value
Net energy (NE)
metabolizable energy minus the heat increment
NFE
nitrogen free extract; consists primarily of readily available carbohydrates such as sugars and starches; part of proximate analysis
Nonprotein nitrogen (NPN)
any one of a group of nitrogen-containing compounds that are not true proteins that can be precipitated from a solution; ammonia and urea are examples
Nutrient
any chemical substance that provides nourishment to the body
Oil
usually a mixture of pure fats that is liquid at room temperature
Oleic acid
an 18-carbon fatty acid that contains one double bond; it is found in animal and vegetable fat
Omasum
the third compartment of the ruminant stomach
Oxidation
the union of a substance with oxygen; the increase of positive charges on an atom or loss of negative charges
Palmitic acid
a saturated fatty acid with 16 carbon atoms
Pancreas
an organ located near the stomach; it produces pancreatic juice, which is secreted into the small intestine via the pancreatic duct. It is also an endocrine gland that secretes insulin and glucagon, hormones that control metabolism of glucose
Pentosan
a polysaccharide made up primarily of five-carbon sugars; araban and xylan are examples
Pentose
a five-carbon sugar such as arabinose, xylose, or ribose
Pepsin
a proteolytic enzyme produced by the stomach
Propionic acid (propionate)
one of the volatile fatty acids commonly found in rumen contents
Protein
any of many complex organic compounds formed from various combinations of amino acids and, sometimes, other nonprotein components
Proximate analysis
a combination of analytical procedures used to describe feeds, excreta, and other agricultural products
Ration
a fixed portion of feed, usually expressed as the amount of a diet allowed daily
Rennin
a milk curdling enzyme present in the gastric juice of young mammals
Reticular groove
a muscular structure at the lower end of the esophagus that, when closed, forms a tube allowing milk to go directly into the abomasum; sometimes referred to as the esophageal groove
Reticulum
the first compartment of the ruminant stomach
Rumen
the second compartment of the ruminant stomach
Ruminant
any of a group of hooved mammals that has a four-compartmented stomach and that chew a cud while ruminating
Rumination
the process of regurgitating previously eaten feed, reswallowing the liquids, and rechewing the solids (cud)
Satiety
the condition of being fully satisfied with food; the opposite of hunger
Saturated fat
a fat that contains no fatty acids with double bonds
Starch
a polysaccharide that yields glucose on hydrolysis; found in high concentrations in most seed grains
Stearic acid
an 18-carbon saturated fatty acid
Sterol
an alcohol of high molecular weight, such as cholesterol; a basic compound used to synthesize many vital chemicals for both plants and animals
Stomach
the part of the digestive tract in which chemical digestion is initiated in most animal species. It normally lies between the esophagus and the small intestine
Sucrose
a disaccharide (common table sugar) composed of one molecule each of glucose and fructose
TDN (Total Digestible Nutrients)
a value that indicates the relative energy value for a feed for an animal
Thyroxine
an iodine-containing hormone that is produced by the thyroid gland
Triglycerides (fat)
an ester composed of glycerol and three fatty acids
True protein
a precipitable protein rather than any of several nonprotein compounds
Trypsin
a proteolytic digestive enzyme produced by the pancreas
Unsaturated fat
a fat containing from one to three fatty acids that contain one or more double bonds
Urea
the chief end product of protein metabolism in mammals; one of the main nitrogenous constituents in urine; a synthetic product sometimes used as a nitrogen source in rations for ruminants
Urease
an enzyme that acts on urea to produce carbon dioxide and ammonia; it is present in numerous microorganisms in the rumen
Uremia
a toxic accumulation of urinary constituents in the blood due to faulty kidney excretion
Uric acid
a nitrogenous end product of purine metabolism; it is the principal nitrogen-containing component in urine of birds
VFA
volatile fatty acids; acetic acid, butyric acid, and propionic acid
Villi
small threadlike projections attached to the interior of the wall of the small intestine to increase its absorptive surface area (singular: villus)
Viscera
the organs of the great cavities of the body, which are removed at slaughter
Vitamin
one of a group of organic substances that is essential in small amounts for the lives of animals
Vitamins, fat soluble
vitamins soluble in fats. This group includes vitamins A, D2, D3, E (tocopherol), and K
Vitamins, water soluble
vitamins soluble in water. This group includes ascorbic acid (vitamin C) and the B complex: biotin, choline, cobalamin or cyanocobalamin, folacin, niacin, pantothenic acid, pyridoxine, riboflavin, and thiamine
