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.


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.


ANABOLISM:

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


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.


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.


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.


BILE

A liver secretion that is necessary for proper digestion of fats.


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...


BROWSE

The part of leaf and twig growth of shrubs, woody vines, and trees that is available for animal consumption.


BUFFER

A chemical substances, such as sodium bicarbonate, that can maintain the pH of the rumen content around neutrality (pH = 6 to 7). The pH is maintained by neutralizing the volatile fatty acids and other organic acids produced by ruminal fermentation.


BULL (CLEAN-UP)

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


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.


COB

The central core of an ear of corn.


DIGESTIBILITY (Coefficient of)

A measure of the proportion of a feed that is digestible. The digestibility of a nutrient is often measured as the difference between the amount of nutrient ingested minus the amount of nutrient excreted in the feces, expressed as a percentage of the nutrient ingested: 100 x (intake - excreted)/intake.


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


EMBRYO

An organism, animal or vegetal, at its early stage of development.


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.


HEMOGLOBIN

An iron rich protein found in the red blood cells which function as a carrier of oxygen and carbon dioxide.


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.


MICROBE

Animal or vegetal organism of microscopic dimension (syn Microorganism).


MORBIDITY

Morbidity is an incidence of ill health. It is measured in various ways, often by the probability that a randomly selected individual in a population at some date and location would become seriously ill in some period of time. Contrast to mortality.


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).


OBESE

extremely fat.


PALATABILITY

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


RHIZOBIUM

A type of bacteria that live in association with the roots of legume plants and make the nitrogen of the air available to the plants.


STILLBORN CALF

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


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.


SYMBIOSIS

The intimate living together of two dissimilar organism in any of various mutually beneficial relationships.