DS 825 Ruminant Nutrition Physiology DS 825 Ruminant Nutrition Physiology Glossary

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.

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

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

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).

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.

(see minerals)

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

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

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

A polymer - long chain- of glucose units. Cellulose is the most abundant organic matter in the world. It is a major component of plant cell wall. Ruminant can use cellulose as an energy source because of fermentation by bacteria in the rumen.

The thick and yellowish secretion collected from the mammary gland at the first milking after calving. The colostrum is low in lactose but normally high in total solid (24%). It is rich in fat, proteins and antibodies that help the new born calf to fight infectious diseases. The secretion collected from the second to the eighth milking is referred to as "transition milk" because of it intermediate composition between colostrum and whole milk.

A measure of the concentration of matter per unit of volume (e.g., g/l or kg/m3)

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

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.

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

The nutritive tissue of a plant seed, surrounding and absorbed by the embryo.

A measure of the concentration of energy in a feed or a ration usually expressed as a unit of energy (megacalorie or megajoule) per lb of dry matter or per kg of dry matter.

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.

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.

The unborn young.

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

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.

A sweet sugar occurring in many fruits and honey.

The stomach and the intestine as a functional unit.

A six carbon sugar which is the building block of starch and cellulose. Glucose is rapidly fermented into volatile fatty acids by ruminal bacteria.

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

A type of carbohydrate similar to cellulose except that it contain not only glucose but also other 6 carbon sugars and also 5 carbon sugars.

Outer envelop, usually green, of fruits and seeds, as around an ear of corn (syn hull).

Decomposition of a chemical compound by reaction with water.

The arrangement of flowers on a stalk that characterizes a plant species.

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

A condition characterized by a lack of appetite, especially for concentrates and an abnormally high concentration of ketone bodies (e.g., acetone, hydroxy-butyrate) in the blood. Ketosis or acetonemia occurs when the cow mobilizes large amounts of body reserves in early lactation.

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

Inflammation of the sensitive vascular tissue of the hoof.

A sedimentary rock, chiefly calcium carbonate (CaCO3), containing variable amounts of magnesium. It is used as building stone, but also as a source of calcium in ration of animals.

An enzyme that breaks down fat.

Protein coated packages that transport fats in the bloodstream

One of the 20 amino acids constituting the building blocks of proteins. Animals have a high requirement for lysine, and it is often deficient in proteins of plants.

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

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

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

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).

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.

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

Inflammation of the uterus.

(see Microbe).

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

A cow that has given birth more than once.

(see non-fiber carbohydrate).

extremely fat.

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.

This is a German word that refers to leftovers of a meal. In dairy nutrition the orts is the amount of feed refused from a daily offering. In dairy nutrition research, orts must be sampled and analyzed in order to calculate with precision the consumption of dry matter and nutrients by the cow. Orts expressed as a percent of dry matter offered is a criteria to determine whether an animal was fed ad libitum (Syn: refusals).

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

A digestive enzyme found in the gastric juice that breaks down proteins into peptides.

The process by which the chlorophyll of plants converts carbon dioxide and water into simple sugars with the simultaneous release of oxygen.

To free from coarseness; to refine.

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

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.

1. The degree with which a measurement is reproducible, that is, yielding similar results when repeated (see also Accuracy).
2. the number of significant digits to which a value has been reliably measured.

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

Digestive enzyme that breakdown proteins into peptides.

The passage connecting the stomach (abomasum) to the duodenum.

A deficiency disease resulting from a lack of vitamin D or lack of sunshine exposure, characterized by defective bone growth.

see diarrhea.

The movement of a material from one place to another. Secretion is often required to move a material to the place where it can be excreted. Examples of materials secreted include all materials excreted (see Excretion above), plus enzymes, hormones and saliva. The organs that play a role in secretion include all those involved in excretion, plus the digestive glands like salivary glands, pancreas, liver and gallbladder and endocrine glands like the thyroid gland, pituitary gland, and ovaries and testes.

A fertilized and ripened plant ovule containing an embryo capable of germinating to produce a new plant.

The probability that a test is positive, given that the animal has the disease (See also specificity).

The clear yellowish fluid obtained upon separating the clotted whole blood into its liquid and solid (red and white blood cells) components.

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.

Structure constructed to help preserving forages as silage. Different types of silos includes: Tower silo, oxygen limiting silo, trench silo, etc.

A cavity formed by a bending or curving; a dilated passage.

(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.

The probability that a test is negative, given that the animal does not have the disease (see also sensitivity).

A ring-like muscle that maintains constriction of a bodily passage or orifice and opens upon relaxation.

To grow or to develop quickly (syn to germinate).

The main stem of an herbaceous plant.

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.

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.

The main upward growing axis of a plant, usually above the ground and in direction opposite of the roots.

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

Fodder; mature-cured stalks from which seeds have been removed, such as stalks of corn or stalk of sorghum without heads.

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

(see Fibrous carbohydrate).

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.

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.

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

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.

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.

Digestive enzyme secreted by the pancreas and responsible for the break down of peptide bonds of proteins. Some plants contain a trypsin inhibitor that prevent trypsin from functioning properly.

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

Particles that carry cholesterol and fat throughout the bloodstream. These particles are released from the liver into the bloodstream. They are similar to chylomicrons which originate from the gut because they both carry cholesterol and triglycerides which are gradually released in the bloodstream to be absorbed by body cells along the way. In the process of losing triglycerides, the VLDLs grow smaller and turn into LDLs (Low Density Lipoprotein) which have lost all their triglycerides.

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

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.