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GLOSSARY

-Abomasum: true stomach of the ruminant.

-Alkali, base: Chemical compound, either inorganic or organic with a high pH value. Acids have completely contrasting and low pH levels. Caustic soda (NaOH) is a strong inorganic base alkali, ammonia (NH3) is a weak organic base alkali. Their strength characterises their aptitude to neutralise an acidic environment and vice-versa.

-Amino acids: basic unit of proteins; they have at least an amine and an acidic function.

-Ammonia pool: ammonia in the rumen which is available for the microorganisms.

-Ammonia nitrogen: nitrogen contained in the ammonia.

-Anaerobic: taking place in the absence of oxygen, referring to a microorganism. The microorganisms in the rumen live in an anaerobic environment.

-Angady: the name in Madagascar given to a very deep digging spade with a narrow, straight and long blade which is curved inwards rather like guttering pipe and has a short handle; used for digging irrigation dikes, trenches, holes, …

-Appetite: stimulation to satisfy hunger, desire for food.

-Armako: A Danish company which has perfected a method to treat straw by injecting ammonia with a tractor-mounted fork with hollow prongs, connected to a reservoir of ammonia. The bale of straw, normally round, is then pushed, inside a plastic sheath, like a sausage, by means of a special device that unrolls the sheath around the bales.

-ATP; adenosine triphosphate: molecule storing the energy needed for metabolism of the animal.

-Bagasse: fibrous residue left after juice extraction from cane sugar by pressing.

-Banco: mixture of clay and chopped straw used (in the Sahel) for making sun-dried bricks or used as a cement for constructing traditional style buildings.

-Belly, paunch or rumen: see“Rumen”.

-Brewer's spent grain: made up of the barley residues from the brewery industry, which are rich in digestible cell matter.

-Ca(OH)2: slaked lime, calcium hydroxide (a less strong alkali base than NaOH (caustic soda) but stronger than NH3 (ammonia)) which is made by adding water to quick lime (CaO).

-Calabash: fruit almost completely round and serving as a traditional receptacle after extracting the pulp and drying it.

-Capacity of Intake (often wrongly called “appetite”): this describes the amount of feed which will be voluntarily ingested by the animal. It is a characteristic which applies to an individual animal and depends upon its species, race, physiological condition, … It depends upon the rate by which it expends energy, hence its level of production. It is expressed in Units of Encumbrance (UE see § 533).

-Catalytic: this is said referring to a constituent, a substance (catalyst), which helps a process or a reaction (chemical, biochemical, …).

-Cell walls: the cellular membrane is made up of a number of vegetal constituents (cellulose, hemicelluloses, substances based on pectin, lignin). The cell walls become increasingly more lignified as the plant matures. Straw is made up of cell wall material which is highly lignified.

-Cellulase: see also “enzyme” and “hydrolysis”. An enzyme which “breaks” or “slices” the cellulose molecule into shorter chains through the action of cellulolysis.

-Cowpea: a variety of bean, Vigna unguiculata. Known as “niébé” in French, an ouolof word.

-Crude Protein (CP); total nitrogenous matter, equivalent to N x 6.25: the ensemble of the nitrogenous constituents of the feed: proteins, free amino acids, amides, nitrates, … They contain on average some 16 % of nitrogen. CP is thus the product of the nitrogen content multiplied by 6.25 (i.e. 100/16).

-DCP; Digestible Crude Protein: the amount of crude protein ingested, reduced by the amount which is excreted in the faeces. The DCP content of a feed is calculated by multiplying the crude protein content (CP) by the apparent digestibility of the nitrogen (§ 532).

-Degradability (of the dry matter, the dietary nitrogen, …): the proportion (of the dry matter, the dietary nitrogen, …) which is degradable by the rumen's microbe population.

-Degradable dietary nitrogen: nitrogen from the dietary crude protein which can be degraded in the rumen (and the reticulum) or used directly by the microbial population of the rumen.

-Digestibility: the (apparent) dry matter digestibility (DMD) or the organic matter digestibility (OMD) of a feed material is the proportion of its dry matter or of its organic matter which disappears in the digestive tract.

-Digestibility “in situ” or “in sacco”: measurement method which allows estimation of the digestibility of a feed by introducing a sample contained in a small nylon bag suspending it in the rumen of an animal carrying a fistula (§ 53).

-DM: Dry Matter (content): the dry components of feed after this has been oven dried at a temperature which alters them as little as possible (40 to 80°C) and for sufficient time (24 to 48 hours) until a constant weight is obtained. The DM content of a forage represents the ratio of its dry to its fresh weight (expressed as a percentage).

-Encumbrance (of the rumen): forages cause an effect of encumbrance during their digestion in the rumen where they are retained to be reduced to particles of a size which is sufficiently small to break through the omasal reticular orifice (ORO). This is measured by the amount of DM present in the rumen. The encumbrance of a forage is greater when digestion is slow (old forage, lignified cell matter) (§ 132).

-Enzyme (old name: diastase): a soluble organic substance which acts as a catalyst in a biochemical reaction. The enzymes which are most frequently mentioned in this text are the digestive enzymes (cellulase, proteases, amylases, …) which assist the hydrolysis of the feed components (cellulose, proteins, starch, …).

-Exothermic, endothermic: said of chemical or biochemical reactions which either give off heat (exothermic) or absorb heat (endothermic).

-Faeces: solid excrement (dung, droppings). They are made up of feed components which have not been digested, bacteria and endogenous constituents (originating from the organism of the animal, such as cells which become detached from the digestive tract, secretions from the digestive process, …).

-Folds, omasum: the third of the pre-stomach compartments which leads to the abomasum.

-Heteropolymers: complex molecular chains made up from various polymers.

-Honeycomb stomach, reticulum or reservoir: see “Reticulum”.

-Hulled rice: rice which has had the husk removed (sometimes called “decorticated” rice).

-Hydrocarbons: binary compounds made up from carbon and hydrogen. Petrol is a hydrocarbon.

-Hydrolysis: rupture of a chemical bond by attaching water molecules, assisted by the enzyme hydrolase which acts as a catalyst. Ureolysis is the reaction of hydrolysis of the urea molecule in the presence of water, assisted by the catalytic action of urease, a ureolytic enzyme (produced by ureolytic bacteria).

-Hygroscopic: showing a tendency to absorb moisture (affinity).

-Ingestibility (a made-up word): the amount of forage ingested which reflects its aptitude for voluntary ingestion when it is provided as a feed (§ 533). Ingestibility is a special characteristic of the forage; it is measured on a group of animals with similar ingestion capacity so as to compare forages in a manner independent to the animal. It is expressed in Units of Encumbrance (UE). It depends also on the palatability of the forage.

-IU; International Units: an internationally standardised system of units for quoting the concentrations of vitamins.

-IVD; “in vitro” Digestibility: measurement method which allows estimating the digestibility of a feed by the action of the rumen juices on a sample introduced into a tube maintained outside the rumen (“bain-marie”) but under similar physical and chemical conditions to those in the rumen (temperature, pH, anaerobic atmosphere) (§ 53).

-Licking (pecking): livestock often adopt the habit of licking each, sometimes until skin is removed. This is owing to a deficiency in feed supplies. In aviculture, one notices a similar tendency for the birds to peck each other, pulling out their plumes.

-Lignin: a huge three-dimensional molecule made up of three basic phenol units. It incrusts the thin walls of cell matter and impedes their degradation by the microbial population in the rumen and in the large intestine.

-Metabolic weight (P0.75): liveweight raised to the power 0.75. This translates the fact that the needs for maintenance and the capacity of intake vary according to the body surface rather than liveweight. It allows comparison of feed needs and ingestion capacity of animals of different weights.

-Metabolism: the ensemble of the chemical and biochemical transformations which are achieved by the animal's organism.

-Mobilisation, storage, body reserves: physiological process depending upon nutrition and hormones which allows the animal alternatively to call upon its body reserves when the intake of nutritional elements is less than its requirements for maintenance and production, or to store them as fat when this is in excess of these same requirements.

-MVS; Mineral Vitamin Supplement: a feed supplement made up mainly of minerals, the major elements, trace elements and a vitamin supplement.

-NaOH: caustic soda, sodium hydroxide, a strong alkali base.

-NH3, NH4OH: chemical formulae for ammonia and aqueous ammonia, respectively.

-Nomadism: non-sedentary pastoral mode of life for which livestock management constitutes the main resource. Nomadic populations are itinerant, following seasonal patterns but not necessarily returning to the original point of departure (in contrast to “transhumance” when they do).

-Non protein nitrogen, NPN: nitrogen from the dietary crude protein which is not in the form of proteins: freed amino acids, amides … Urea represents an industrial source of NPN.

-Olive cake: cake made from the residue left after extraction of oil from olives made up from the pulp and the kernels.

-Omasum, folds: the third of the pre-stomach compartments which leads to the abomasum.

-ORO; Omasal Reticular Orifice: orifice connecting the reticulum with the omasum.

-Oses (hexoses, pentoses, …): simple carbohydrates with six atoms of carbon (C) for the hexoses (eg. glucose), and five C for the pentoses (eg. xylose).

-Paddy rice: rice which has not had the husk removed.

-Palatability, acceptability: the whole combination of the physical characteristics (bearing of the plant, sharpness, …) and the chemical characteristics (smell, taste, …) which affect the appetite of the animal.

-Paunch, belly or rumen: see “Rumen”.

-PCV (Plastic): polyvinyl chloride, a plastic material used for making thin sheet and covering which is often used in agriculture (Chapter 3, Treatment with ammonia).

-PDI: “Protéines vraies réellement Digestibles dans l'Intestin grêle” i.e. true Protein truly Digestible in the small Intestine (§12) (INRA, 1988).

-PDIA (by-pass N): “Protéines Digestibles dans I'Intestin d'origine Alimentaire” i.e. dietary protein undegraded in the rumen, but truly digestible in the small intestine (INRA, 1988).

-PDIM: “Protéines Digestibles dans l'Intestin d'origine Microbienne” i.e. microbial true protein which is truly digestible in the small intestine (INRA, 1988). They are PDI originating from proteins formed by the microbial population in the rumen (and the reticulum).

-Pecking (licking): seen above all in aviculture where, owing to a deficiency in feed supplies, the birds peck each other, pulling out their plumes. Other livestock adopt similar habits and may lick each other until skin is removed.

-Peptide: molecule made up through the assembly of a small number of molecules of amino acids.

-pH: coefficient based on the concentration of H+ ions in a solution or an environment which characterises the acidity or the alkali base of this solution or environment. This is acidic if the pH is less than 7, alkaline (or basic) if it is greater than 7, a neutral solution or environment having a pH of 7 (§ 132).

-Phenols (substances, acids, units,…): having a benzene cluster containing hydroxide (an OH bond).

-Polymers: molecular chains made up of a sequence of identical and simple molecules.

-Polysaccharides (polyosides in French): complex carbohydrates, polymers from oses.

-Pounding rod: a hand tool consisting of a heavy mass at the end of a rigid stake and equipped with two handles which is used to bed down paving stones or to compact soil, materials, etc… It may be used for compacting multinutrient blocks in their moulds.

-Precursors (for the glucose, for microbial synthesis, …): the raw material (substances, molecules,…) needed for the synthesis of substances which will be used by the animal.

-Quality labels (plastic sheeting): indicating the quality (strength, thickness, …) which is guaranteed by the manufacturer. A sheet labelled 150 μm is guaranteed to have a thickness of 150 μm (microns).

-Reservoir, reticulum, or honeycomb stomach: see “Reticulum”.

-Reticulum, reservoir, or honeycomb stomach: the second compartment of the three pre-stomachs, much smaller than the rumen from which it leads. It is within the combination of the reticulum and the rumen where the microbial digestion of the feed takes place.

-Rumen, paunch or belly: first of the three pre-stomach compartments of ruminants which is by far, the most important.

-Séko: traditional matting made by weaving leaves from dry grasses (generally made from Andropogon gayanus). Commonly used in the Sahel region.

-Tannin: a non cell wall polymer made up of various phenols.

-TDN; Total Digestible Nutrients: the American system for quantifying the energy value of feed. It is equal to the sum of the Digestible Crude Protein (DCP), the Digestible Crude Fibre (DCF), the Digestible Nitrogen Free Extracts (DNFE) (carbohydrates) and the Digestible Ether Extracts (DEE) (lipids), this last component being multiplied by a factor of 2.25. The calculated value then can be expressed as: TDN (g/kg DM) = DCP + DCF + DNFE + 2.25 × DEE

-TLU: Tropical Livestock Unit (Unité de Bétail Tropical or “UBT” in French); a bovine with a standardised liveweight of 250 kg.

-Trace elements: minerals which only occur in very low concentrations in living beings (Fe, Zn, Mn, Cu, Co, I, Mo, Se). The minerals occurring in higher concentrations are known as the major elements (P, Ca, Mg, Na, K, Cl, S).

-Transhumance: seasonal movement of flocks and herds in the search of feed. (Not to be confused with “nomadism”).

-UBT: unité de bétail tropical (Tropical livestock unit or TLU in English): a bovine with a standardised liveweight of 250 kg.

-UF; Feed Unit: the amount of Net Energy (NE) contained in one kg of a reference sample of barley (870 g of DM). In the French system (using these units), one may distinguish between a Feed Unit for Milk (UFL) destined for milk production (NE for Milk) (where 1 UFL = 1.70 Mcal of NE for Milk) and a Feed Unit for meat production (UFV) (where 1 UFV = 1.82 Mcal of NE for Maintenance and Meat); this latter UF component is for maintenance and growth of an animal being fattened at a production rate of 1.5 (the ration of 1.5 being that of the production requirements as compared to those for normal maintenance).

-Urease: see “Enzyme” and “Hydrolysis”. The enzyme which “breaks” or “splits” the urea into aqueous ammonia and carbon dioxide (CO2).

-VFA; volatile fatty acids: the main end products due to fermentation of the carbohydrates in the rumen. The most important are acetic, propionic and butyric acids.


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