Abomasum

The fourth digestive chamber of the digestive system of most ruminants. The abomasum is located after the forestomachs (rumen, reticulum and omasum) and before the first segment of the small intestine (i.e., the duodenum); It is sometimes referred to as the "true" stomach because of its acid-secreting ability, which is found in most other mammalian species.


Accuracy

The degree with which a measurement matches the actual, true or target value (see also Precision).


Acidosis (rumen)

Condition characterized by a low rumen pH (below 6). The normal rumen function are impeded usually because too much concentrates were fed.


Ad Libitum

A latin word that means "to one's pleasure." In nutrition, ad libitum (abbreviated "ad Lib") refers to feeding management in which animals are fed without restriction. Cows are usually considered fed ad libitum when the refusals (orts) amount to approximately 5 to 10% of what has been offered the day before.


Allometric (equation)

Allometric equations take the general form Y = aMb, where Y is some biological variable, M is a measure of body size, and b is some scaling exponent. See West et al. (2012) for more details.


Allometry

The growth of body parts at different rates, resulting in a change of body proportions.


AMINO ACID

One of the 20 building block units of protein. Amino acids contain both an amino group (NH2) and an acid or carboxyl group (COOH).


AMMONIA (NH3)

A pungent gas. Ammonia is extensively used to manufacture fertilizers and nitrogen containing compounds. Also, ammonia is the end-product of protein degradation by ruminal bacteria.


ANABOLISM:

The part of the metabolism in which metabolites are used in the growth and repair of body tissues.


ANEMIA

A disease due to a deficiency in red blood cells or in hemoglobin that carries oxygen in the blood.


ANTIBODY

Protein released in the blood that is generated in reaction to a foreign protein (antigen) that has entered the body. Antibodies produce immunity against certain micro-organisms or their toxins.


APPETITE

Desire for food that can be quantify by measuring dry matter intake.


ARTIFICIAL INSEMINATION

Reproductive procedure by which semen previously collected from sires, packaged in “straws” and frozen in liquid nitrogen is thawed and manually deposited in the uterus of a cow in estrus, in the hope of conception. Artificial insemination is a technology that allows for genetic improvement based on selection and use of superior sires.(see also Timed Artificial Insemination).


AS-IS BASIS

A method of expressing the concentration of a nutrient in a feed. For example, a feed containing 12% crude protein on a dry matter basis contains 12 g of protein for each 100 g of feed "as-is" (or "fresh"). When feed ingredients are added to a mixer, they are weighted on an "as-is" of "fresh" basis. See also "Dry Matter Basis.


ASH

(see minerals)


BACTERIA

Single-cell organisms living either independently or in close association with other living organisms. Often referred to as microbes or microorganisms because of their microscopic size. Some bacteria are beneficial, but others cause infectious diseases.


Bezoar

A small stony concretion that may form in the stomachs of certain animals, especially ruminants. Bezoars are caused by a buildup of material in the gastrointestinal tract that the stomach can't digest.


BIOLOGICAL VALUE (of a protein)

A measure of protein quality. The percentage of protein in a feed which is not lost in the urine or the feces of the animal. Biological value is a reflection of the balance of amino acids available to the animal after digestion and absorption.


BLOAT

A swelling of the left side of the cow caused by a frothy material which prevents gases of fermentation from being eructed from the rumen. Occurs primarily when cows are grazing certain species of legumes especially, alfalfa. If not treated immediately, bloat can cause death in a matter of hours. More...


BULL (CLEAN-UP)

A bull used for natural mating after mutiple artificial insemination attempts have failed to establish pregnancy.


CALORIE

A unit of heat that can be used to measure the amount of energy in a feed or a ration. A calorie is the amount heat required to raise the temperature of 1 gram of water from 14.5 ° centigrade to 15.5 ° centigrade.


CALVE (to)

(see Parturition)


CARBOHYDRATE

Any of a group of chemical compounds, including sugars, starches, and cellulose, containing only carbon, hydrogen, and oxygen, with a ratio of hydrogen to oxygen of 2:1.


CARBON DIOXIDE (CO2)

A gas produced by combustion or oxidation of organic matter. Carbon dioxide is also produced in large quantities during ruminal fermentation.


CATABOLISM

The part of the metabolism in which metabolites are oxidized for the production of work and heat.


CATALYST

A substance present in small amounts that increases the rate of chemical or biochemical reactions without being consumed in the process.


CELL WALL

Fibrous structure that provides rigidity to the plant. The cell wall is composed of digestible fibrous carbohydrates (cellulose; hemicellulose and pectin) and an indigestible phenolic compounds (e.g., lignin and tannin).


CEREAL

A plant in the grass family (gramineae), the seeds (i.e., grain) of which are used for human and animal food (e.g., maize, rice and wheat).


CHAFF

Glumes, husk, or other seed coverings, together with the plant parts, separated from seeds in threshing or processing.


CLINICAL

Involving or based on direct observation of the patient (a clinical diagnosis). A clinical disease is a disease that can be diagnosed by examination because of signs / symptoms of discomfort, anomalies of the normal state


CONCENTRATE

Feedstuffs usually rich in energy and coming from the part of the plant that accumulate nutrient reserves for an embryo (fruits, nuts, seeds and grains). The word concentrate is also used to refer to the mixture of minerals and other supplements used to feed dairy cattle.


DIARRHEA

Pathologically excessive evacuation of watery feces. Diarrhea may be due to an infectious agent (bacterial infection) or a dietary imbalance.


DIGESTA

The mixture of digestive secretion, bacterial population and feeds undergoing digestion in the gastro-intestinal tract (such as rumen content).


DRY MATTER

That part of the feed which is not water. It is usually determined by the residual weight of a sample placed for a period of time in a drying oven that removes the water from the sample. Usually, the dry matter content of a feed is expressed as a percentage. For example, an hay of 85% dry matter contains 85 g of dry matter for each 100 g of fresh feed.


DRY MATTER BASIS

A method of expressing the concentration of a nutrient in a feed. For example, a feed containing 12% crude protein on a dry matter basis contains 12 g of protein for each 100 g of feed dry matter


DRY MATTER INTAKE

Quantity of dry matter ingested by a cow in a 24 h period. For example, a cow eating 18 kg of grass silage of 33% of dry matter ingest 18 x 0.33 = 6 kg of grass silage dry matter.


EAR (of corn)

The seed-bearing part of a cereal plant. An ear of corn is composed of the grains, the cob, but not the husk, which are removed during harvesting.


ENROLLMENT PLAN

Method used to select cows which are eligible for hormonal treatment (such as Ovsynch). For example, the enrollment plan may be defined by the voluntary waiting period or a negative pregnancy check.


FALSE NEGATIVE

An animal that tests as negative but who is actually positive. The percent of false negative for a test can be calculated as 100 – SENSITIVITY.


FALSE POSITIVE

An animal that tests as positive but who is actually negative. The percent of false positive for a test can be calculated as 100 – SPECIFICITY.


FAT

1. Ester of glycerol and fatty acids. 2. Organic compound containing carbon, hydrogen and oxygen, but as opposed to the carbohydrates, fats have a ratio of hydrogen to oxygen well above 2:1. Fats, as opposed to oils, are solids at room temperature and usually are of animal origin.


FATTY ACID

A chain of carbon terminated by an acid (carboxyl) group (COOH). Fatty acids with less than 4 carbon units are volatile. Fatty acids with 5 to 20 carbon units are usually found as part of fats and oils.


FERMENTATION (in the rumen)

The transformation of carbohydrates in absence of oxygen by rumen micro flora that produces volatile fatty acids such as acetic acid, propionic acid and butyric acid, and gases such as carbon dioxide (CO2) and methane (CH4).


FIBER (dietary)

Nutrient of low energy density present in large quantities in forages. Fiber is composed of structural carbohydrates (cellulose and hemicellulose) and phenolic compounds. Fiber is important for dairy cows because they stimulate rumination and promote a healthy rumen environment for bacterial growth. However, in large amounts in the diet, fiber may fill the rumen, limit intake of energy and constrain milk production.


FIBROUS CARBOHYDRATE

Hemicellulose and cellulose that can be quantify by the neutral detergent fiber procedure.


FORAGE

Feed that stimulate rumination due to their long particle size and their high content in fiber. Generally, forages are composed of the leaves and stems (stalk of plants. The bacterial population of the rumen allows the ruminant to digest forages.


FORAGE TO CONCENTRATE RATIO

Usually expressed as two percentages. The percentage of ration dry matter that is made up of forage and the percentage of ration dry matter that is composed of concentrates. The two total 100. For example a 50:50 forage to concentrate ratio means that a cow eating 20 kg of dry matter of that ration would eat 10 kg of concentrate dry matter and 10 kg of forage dry matter.


FRUCTANS

Is a polymer of fructose molecules generally, but not always, found as "carbohydrate storage in cool season grasses (C3 plants). Tall fescue and perennial ryegrass tend to have the highest levels of fructans when compared to other grasses under the same conditions. Fructan is stored in vacuoles inside cells throughout the plant where it is readily available as needed. In some species of grass the lower part of the stem is a carbohydrate storage organ.


GASTROINTESTINAL TRACT

The stomach and the intestine as a functional unit.


GERMINATE (to)

To begin to or to cause to grow (syn to sprout.


GRAIN

Seed from cereal plants.


GRAMINEAE

Family of plants including rye grass, fescue, brome, timothy and other herbaceous plants often referred to as grass. Cereals are gramineous plants but often, they are considered apart from the grass because they are cropped for the grain rather than the vegetative parts of the plant.


GRASS

Any of the numerous plants of the family gramineae, characteristically having narrow leaves and hollow, jointed stems (e.g., orchardgrass, ryegrass, bromegrass).


HAY

A sun-dried forage. A method of preserving forage by cutting the plant and letting it dry in the sun.


HEAT PERIOD

A period of 9 to 24 hours preceding the ovulation during which cows are receptive to bulls and exhibit a typical behavior of mounting other cows or standing when mounted by other cows (or a bull).


HYDROCHLORIC ACID (HCl)

Strong acid secreted by the abomasum that breaks down chemical bounds and thus contributes to the digestion of feeds.


INTERNATIONAL UNITS (IU)

A unit of measurement of the amount of biologically active vitamin in a feed or required in a diet.


KILO CALORIE (KCAL)

One thousand calories.


LACTOSE

A disaccharide composed of a unit of glucose and a unit of galactose. Also known as milk sugar, lactose is produced commercially from whey.


LAMINITIS

Inflammation of the sensitive vascular tissue of the hoof.


LAXATIVE

A feed or drugs that will induce bowel movements (defecation) and relieve constipation.


LEAF

Structure, usually flat and green that grows from a stem or stalk of a plant and is responsible for photosynthesis.


LIPASE

An enzyme that breaks down fat.


MAINTENANCE (diet)

A diet that supplies the nutrients required to maintain vital functions (heart beat, respiration) and assure a constant body temperature.


MAINTENANCE (state)

A physiological state in which the animal is neither gaining nor losing weight, performing work or expending nutrients for any type of production.


MAMMALS

A class of vertebrate animals distinguished by self-regulating body temperature, hair, and in the female (a) milk producing gland(s).


MASTICATION

To grind or crush (food) with or as if with the teeth to prepare it for swallowing and digestion (Syn: Chew).


MASTITIS

An infammation of the udder (often caused by a microbial infection) resulting in pain and the secretion of milk with a high count of white blood cells (referred to as somatic cell count).


MCAL

Abbreviation for Megacalorie.


MEAL

1. The episodes of feed ingestion throughout the day.
2. The edible seed or other edible part of a grain, coarsely ground (as opposed to flour which is finely ground).


MEAN (Statistics)

The mean of a normal distribution is the most likely value (the value that has the lowest probability of being "wrong"). The mean is the best measure of central tendency of a normal distribution. With a normal distribution, approximately one-half of the samples have values lower than the mean and one-half have values higher than the mean.


MEGACALORIE

One million calories.


METABOLISM

Refers to all of the changes that nutrients undergo after they are absorbed from the digestive tract. Metabolism is divided into anabolism and catabolism.


METABOLITE

A product of metabolism of nutrients.


METABOLIZABLE PROTEIN

In ruminant nutrion, metabolizable protein, often abbreviated MP, is the amount of digestible protein that reach the small intestine, which is the source of amino acids absorbed into the blood. The three main sources of MP include rumen undegraded protein (the dietary protein fraction that has not been degraded in the rumen), the microbial (bacterial) protein synthesized in the rumen from the fermentation process, and the endogenous protein (intestinal digestive enzymes and sloughed cells from the gastro-intestinal tract). The latter source is minimal.


MICROORGANISM

(see Microbe).


MILL (a)

1. A building equipped with the machinery for grinding grain into flour or meal. 2. A device or mechanism such as rotating millstones, that grinds grain.


MINERAL

1. The inorganic chemical elements (e.g., calcium phosphorus magnesium) determined by combusting a sample in a furnace and weighing the mineral residue. 2. Minerals play major roles in numerous metabolic processes. (syn Ash).


MONOGASTRIC

Having one digestive cavity (i.e., one stomach).


Mortality

is incidence of death in a population. It is measured in various ways, often by the probability that a randomly selected individual in a population at some date and location would die in some period of time. Contrast to morbidity.


MULTIPAROUS (cow)

A cow that has given birth more than once.


NET ENERGY OF LACTATION (NEl)

The amount of energy in a feed which is available for milk production and body maintenance. Feeds generally are similar in total energy content but vary widely in the proportion of the total energy which is available for maintenance and milk production. The remainder of the energy in the feed is lost in the feces urine, gas belched form the rumen and excess heat production by the cow. In the cow, it takes 0.74 Mcal NEl to produce 1 kg of milk containing 4% fat and the net energy content of most feed range from 0.9 to 2.2 Mcal NEl per kg dry matter.


NEUTRAL DETERGENT FIBER (NDF)

A measure of the amount of cell wall in a feed determined by a laboratory procedure. Neutral detergent fiber includes cellulose, hemicellulose and lignin.


NON-FIBER CARBOHYDRATE

Carbohydrates that are not part of the neutral detergent fiber, but generally accumulate in the plant as energy reserve (e.g., starch). These carbohydrates usually are more rapidly and more completely digested than the fibrous carbohydrates (syn Non-structural carbohydrate).


NON-STRUCTURAL CARBOHYDRATE

(see non-fiber carbohydrate).


OMASUM

The third stomach of a ruminant between the reticulum and the abomasum. It is characterized by the presence of muscular leaves that may have an absorptive function.


ORGANIC MATTER

Compounds composed of carbon oxygen hydrogen and nitrogen. All living organisms are composed primarily of organic matter. Fats, carbohydrates and proteins are examples of organic compounds.


OVULATION

Release of an oocyte (i.e., egg) from a mature follicle. In dairy cows, ovulation occurs 24 to 32 hours after the first standing event of behavioral estrous. Similarly, ovulation occurs 24 to 32 hours after an injection of Gonadotropin Releasing Hormone; (Gn-RH) administered in the presence of a dominant follicle.


PALATABILITY

The taste and flavor property of a feedstuffs that make them more or less acceptable to be eaten.


PANCREAS

An irregularly shaped gland that secretes pancreatic juice into the duodenum and produces insulin that is released into the blood.


PAPILLAE (reticulo-rumen)

1. Small projections on the inner surface of the rumen and the reticulum wall that increase the surface area of absorption of volatile fatty acids and other end-products of bacterial fermentation.


PAPILLAE (tongue)

Protuberances at the surface of the tongue that detect the taste of a feed.


PARTURITION

The act of giving birth (Syn Calving).


PLACENTA

An organ that develops during pregnancy in female mammals. It lines the uterus and partially envelopes the fetus, to which it is attached by the umbilical cord. Following birth, the placenta, then called the after birth, is normally expelled. The retention of the placenta usually leads to bacterial infection of the uterus called metritis.


POLYGASTRIC

Having more than one digestive cavity; Having a stomach divided into different chambers (e.g., ruminants).


POPULATION (statistics)

The set of individuals, items, or data from which a statistical sample is taken. In statistical terms, a population is defined as a larger set from which samples are obtained.


PREGNANT

Having one or several fetus growing inside the uterus.


PRIMIPAROUS (cow)

1. A young cow that is pregnant for the first time. 2. A cow that has given birth once.


PROTEASE

Digestive enzyme that breakdown proteins into peptides.


PROTOZOAN

Most primitive form of life in the animal kingdom composed of only one microscopic cell.


RADICLE

The part of a plant embryo that develops into the primary root.


REGURGITATION

Reversal of the natural direction in which contents flow through a tube or a cavity in the body. During rumination, rumen contents are regurgitated through the esophagus in the mouth for further mastication.


SILAGE

Method of preservation of fresh forages based on the partial fermentation of the sugars in absence of oxygen. Silage can be made in various silos.


SOMATIC CELLS

(a) Any of the cells of a plant or animal except the reproductive cells. (b) Milk somatic cells are primarily leukocytes (white blood cells) and some epithelial cells shed from the lining of the mammary gland. The leukocytes are derived from blood and consist of macrophages, lymphocytes, and polymorphonuclear cells, primarily neutrophils (PMN). Normal milk does contain somatic cells, and the concentration of these cells is almost always less than 100,000 cells/ml in milk from uninfected/uninflamed mammary quarters.


STALK

The main stem of an herbaceous plant.


STANDARD DEVIATION (statistics)

Standard deviation (SD) is a measure of the dispersion of a set of data from its mean. If the data points are further from the mean, there is higher deviation within the data set. The SD shares the same unit as the mean. The SD is calculated as the square root of variance by determining the variation between each data point relative to the mean. The symbol for standard deviation is σ (the Greek letter sigma). Approximately, in a normal distribution,
38% of all observations are within ± 0.5 SD units of the mean;
68% of all observations are within ± 1 SD units of the mean;
95% of all observations are within ± 2 SD units of the mean;
99% of all observations are within ± 3 SDunits of the mean.


STARCH

Carbohydrate found chiefly in seeds, fruits, tubers, roots, an stem pith of plants notably in corn, potatoes, wheat and rice. Warm season grasses (C4 plants) store starch in chloroplasts in leaf tissue. C4 grasses such as Bermuda Paspalum or Rhodes grasses grown under heat stress may contain considerable starch in leafy tissue. Nutritionally, it is referred to as non-structural carbohydrate as opposed to the carbohydrate found in the neutral detergent fiber of the plant.


STILLBORN CALF

A calf born dead or that dies within 48 hours of birth.


STRAW

The plant residue remaining after separation of the seeds in threshing. It includes chaff.


STRUCTURAL CARBOHYDRATE

(see Fibrous carbohydrate).


SUBCLINICAL

Without clinical manifestations; said of the early stages or a very mild form of a disease, e.g. subclinical disease, infection, parasitism, or when a disease is detectable by biological tests but not by a clinical examination.


Sustainable Intensification

Narrowly defined, SI refers to increase food production from existing farmland in ways that place far less pressure on the environment and that do not undermine our capacity to continue producing food in the future. However, Garnett et al. (2013) added the following four premises underlying SI: (a) The need to increase production; (b) Increase production must be met through higher yields because increasing the area of land in agriculture carries major environmental costs; (c) Food security requires as much attention to increasing environmental sustainability as to raising productivity; and (d) SI denotes a goal but does not specify a priori how it should be attained or which agricultural techniques to deploy.


TANNIN

Highly complex phenolic compounds in plants that may play a role of defense again microorganisms and possible predators (the herbivores). Tannin binds and reduces the availability of proteins and carbohydrates to ruminal microbes.


TASTE

Property of feed detected by some papillae of the tongue and the roof of the mouth resulting in a positive or negative response to further ingestion of the feed.


THYROID GLAND

A two-lobed gland located in the throat and secreting the hormone thyroxin, which regulates the iodine metabolism in the body.


TIMED ARTIFICIAL INSEMINATION

Method of AI breeding in which the timing of artificial insemination (AI) is based on a hormonal protocol that synchronizes the timing of ovulation. This is in contrast to timing insemination based on direct or indirect detection of estrous behavior. Hormonal protocols for Timed AI were developed in 1995 and have been widely adopted by dairy producers for reproductive management.


TOTAL MIXED RATION (TMR)

Mixture of the forages, concentrates, minerals and vitamin supplements of a ration. The total mixed ration has the advantage of offering a balanced ration at each meal rather than on a 24 h basis.


ULTRA-VIOLET:

Ray in sunlight which enables vitamin D to be synthesized under the skin.


Unit of Mass in Metric System

1,000,000,000,000,000  1x1015 petagram (Pg) quadrillion  
1,000,000,000,000  (Million Metric Tons or Megatonnes)1x1012 teragram (Tg) trillion
 1,000,000,000  (Thousand Metric Tons) 1x109 gigagram (Gg) billion
 1,000,000  (Metric Ton) 1x106 megagram (Mg) million
 1,000   1x103 kilogram (Kg) thousand  
 100   1x102 hectogram (Hg) hundred  
 10   1x101 decagram (Dg) ten  
 1    gram    
   0.1 10-1 decigram (dg) tenth   
   0.01 10-2 centigram (cg) hundredth  
   0.001 10-3 milligram (mg) thousandth  
   0.000,001 10-6 microgram (µg) millionth  
   0.000,000,001 10-9 nanogram (ng) billionth  
   0.000,000,000,001 10-12 picogram (pg) trillionth  
   0.000,000,000,000,001 10-15 femtogram (fp) quadrillionth  


UNSATURATED FAT

Fat containing fatty acids that can accept hydrogen atoms to saturate their structure (e.g., oleic, linoleic, linolenic and arachidonic acids).


UREA [CO(NH2)2]

A nitrogen-containing organic compound found in urine and other body fluids. Urea is synthesized from ammonia and carbon dioxide. Urea can be used as fertilizer or as a source of nitrogen in the ration of ruminants.


VEGETATIVE

The parts of plants that are involved in the growth as opposed to the parts of plants involved in reproduction.


VITAMINS

Complex organic substances occurring naturally in plants and animal tissue and essential in small amounts for the proper functioning of numerous metabolic processes.


VOLATILE

Evaporating readily at normal temperature and pressure.


VOLATILE FATTY ACIDS (VFA)

Products of fermentation of carbohydrates (and some amino acids) by the rumen microorganisms. Acetic acid, propionic acid and butyric acid are the primary volatile fatty acids which are absorbed through the rumen wall and used as an energy source by the cow.


VOLUNTARY WAITING PERIOD

The number of days between calving and first attempt to breed a cow. A typical voluntary waiting period is 45 days. However, it may varies from less than 40 to 80 days depending on farmer’s preference and reproductive protocol in place on the farm.