Feed phosphates
Encyclopedia
Inorganic Feed Phosphates
Inorganic feed phosphates (IFP) are inorganic salts of phosphoric acid
. The use of inorganic feed phosphates is necessary to meet the phosphorus
requirements for animal production: to ensure optimal growth, fertility
and bone development.
. About 80% of the animals phosphorus is located here, co-precipitated with calcium
(Ca) in the form of hydroxy-apatite complex (Ca10(PO4)6(OH)2), where it acts not only as a support system but also as a reservoir of phosphorus. In the soft tissue
s, phosphorus is a major component of the cell
s, membrane
s and body fluids. But also plays an important role in the energy supply. In addition phosphorus acts as a buffer, is involved in phospholipid
s and fatty acid
s transfer, in the formation of amino acid
s and in makes part of DNA
and RNA
. Therefore, phosphorus is indispensable for live and animals cannot live without.
. Large deposits exist in Russia
, USA
, North Africa
, China
, where they are obtained mostly by open cast mining. Over 85% is used in fertiliser production and only less than 7% in feed phosphate production. Two types of deposits exist; of volcanic and of sedimentary origin.
These crude phosphates cannot be used by animals directly but must be converted into a form which can be digested by the animal. In addition, the undesired impurities must be removed or lowered towards an acceptable level. The starting point of industrial feed phosphate production is technically pure (ortho) phosphoric acid (H3PO4) which is obtained from the apatite
in a wet chemical process.
and worldwide are calcium phosphate
s in different forms (mono-, di- and monodi-calcium phosphates) but also magnesium phosphate
s, sodium phosphates and even ammonium phosphate
s are used in animal nutrition
. The end-product quality depends on the treatment and production process. Due to different chemical compositions of the different feed phosphate sources, large differences do exist in their phosphorus availability for the different animal species
. However phosphate from the same source, produced by the same process, using the same raw materials, show consistent phosphorus availability, which can be measured in biological assays.
during the process, to avoid degradation of orthophosphate into other unavailable phosphate forms. Impurities which are naturally occurring in the used raw materials must also be considered. But also feed hygiene and good manufacturing
practices should be complied with at all stages.
In addition calcium and vitamin D
levels must be optimized because phosphorus metabolism
is closely linked to these and symptoms of deficiency can be intensified if not taken into respect properly.
levels, followed by withdrawal of calcium and phosphorus from the skeleton. Loss of appetite and reduced productivity are common in all animal species. A poor feed conversion efficiency and a lowered live weight gain
are well known production related indicators. Other deficiency includes reduced fertility in cattle, but also reduced milk yield (milk contains on average 1 g of P per kg), stiffness and in extreme cases even enlarged joints or deformed bones and lameness. Other well known symptoms are In layers reduced egg yield and, in case of chicks, reduced hatchability, together with cage layer fatigue syndrome. Also for all species osteomalacia
and reduced fertility are possible. All these symptoms are more or less irreversible, resulting in economical losses for the farmer.
and metabolism differ substantially between ruminant
and non-ruminant (monogastric
) species. In pig
s, most phosphorus is absorbed from the small intestine
-jejunum
, duodenum
- in the form of ortho-phosphate where its solubility is greatest. The phosphorus is then transported across the gut wall. The kidney
plays the major regulatory role in controlling phosphorus levels, any excess is excreted primarily via the urine
. In poultry
available phosphorus solubilises in the gizzard
where it becomes available for absorption also in the duodenum and jejunum.
Ruminants have a digestion system whereby micro-organisms in the rumen
produce enzyme
s breaking down and thereby making available phosphorus from plant material. Phosphorus from plant sources is therefore better suited to ruminants’ but is still utilized to a lesser extent than phosphorus provided by inorganic sources. The ruminant needs for phosphorus is dictated by the needs of the microbial population in the rumen, with the phosphorus being necessary for cellulose
digestion and protein synthesis. The main source is phosphorus recycled by the saliva
, a peculiarity of ruminants’. Phosphorus is mainly absorbed in the small intestine and homeostasis
is achieved by excretion
of phosphorus with the faeces.
s originates from the vegetal feed materials to compose these feeds. However, up to 80% of the phosphorus present in vegetal feed materials is in the form of phytate. Unfortunately, and in contrast to ruminants, poultry and pigs lack the enzyme necessary to break down this phytate-phosphorus. Therefore, phosphorus digestibility of plant phosphorus varies between 6% and 50%, and it is assumed that at least two thirds of the organic phosphorus in the diet is unavailable for pigs and poultry. That’s why normally phosphorus in the form of high quality inorganic feed phosphates has to be supplemented to diets of high producing farm animals.
s closer to the requirements. This can be carried out by, amongst others, the use of highly digestible feed materials including the use of high quality inorganic feed phosphates. High quality inorganic feed phosphates are supplemented to make up the deficit between requirements and allowances.
Inorganic feed phosphates (IFP) are inorganic salts of phosphoric acid
Phosphoric acid
Phosphoric acid, also known as orthophosphoric acid or phosphoric acid, is a mineral acid having the chemical formula H3PO4. Orthophosphoric acid molecules can combine with themselves to form a variety of compounds which are also referred to as phosphoric acids, but in a more general way...
. The use of inorganic feed phosphates is necessary to meet the phosphorus
Phosphorus
Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...
requirements for animal production: to ensure optimal growth, fertility
Fertility
Fertility is the natural capability of producing offsprings. As a measure, "fertility rate" is the number of children born per couple, person or population. Fertility differs from fecundity, which is defined as the potential for reproduction...
and bone development.
Importance
The importance of phosphorus (PO43-) is reflected in the number of metabolic functions in which the element takes part. By far the greatest portion of phosphorus is devoted to maintain and support the skeletonSkeleton
The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...
. About 80% of the animals phosphorus is located here, co-precipitated with calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
(Ca) in the form of hydroxy-apatite complex (Ca10(PO4)6(OH)2), where it acts not only as a support system but also as a reservoir of phosphorus. In the soft tissue
Soft tissue
In anatomy, the term soft tissue refers to tissues that connect, support, or surround other structures and organs of the body, not being bone. Soft tissue includes tendons, ligaments, fascia, skin, fibrous tissues, fat, and synovial membranes , and muscles, nerves and blood vessels .It is sometimes...
s, phosphorus is a major component of the cell
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
s, membrane
Biological membrane
A biological membrane or biomembrane is an enclosing or separatingmembrane that acts as a selective barrier, within or around a cell. It consists of a lipid bilayer with embedded proteins that may constitute close to 50% of membrane content...
s and body fluids. But also plays an important role in the energy supply. In addition phosphorus acts as a buffer, is involved in phospholipid
Phospholipid
Phospholipids are a class of lipids that are a major component of all cell membranes as they can form lipid bilayers. Most phospholipids contain a diglyceride, a phosphate group, and a simple organic molecule such as choline; one exception to this rule is sphingomyelin, which is derived from...
s and fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
s transfer, in the formation of amino acid
Amino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
s and in makes part of DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
and RNA
RNA
Ribonucleic acid , or RNA, is one of the three major macromolecules that are essential for all known forms of life....
. Therefore, phosphorus is indispensable for live and animals cannot live without.
Production of Inorganic Feed Phosphates
Phosphates occur widely in nature mostly as phosphate rock or fluorapatiteFluorapatite
Fluorapatite, often with the alternate spelling of fluoroapatite, is a mineral with the formula Ca53F . Fluorapatite is a hard crystalline solid. Although samples can have various color , the pure mineral is colorless as expected for a material lacking transition metals...
. Large deposits exist in Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
, USA
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, North Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
, China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, where they are obtained mostly by open cast mining. Over 85% is used in fertiliser production and only less than 7% in feed phosphate production. Two types of deposits exist; of volcanic and of sedimentary origin.
These crude phosphates cannot be used by animals directly but must be converted into a form which can be digested by the animal. In addition, the undesired impurities must be removed or lowered towards an acceptable level. The starting point of industrial feed phosphate production is technically pure (ortho) phosphoric acid (H3PO4) which is obtained from the apatite
Apatite
Apatite is a group of phosphate minerals, usually referring to hydroxylapatite, fluorapatite, chlorapatite and bromapatite, named for high concentrations of OH−, F−, Cl− or Br− ions, respectively, in the crystal...
in a wet chemical process.
| Example of phosphoric acid production Wet process phosphoric acid is prepared by adding sulfuric acid Sulfuric acid Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates... (H2SO4)to apatite or tricalcium phosphate rock resulting in the following reaction: 3 H2SO4 + Ca3(PO4)2 + 6 H2O ↔ 2 H3PO4 + 3 CaSO4•2H2O Wet-process acid has to be purified by removing fluorine Fluorine Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic... and other undesirable elements to produce feed-grade phosphoric acid. |
Different types of inorganic feed phosphates
Depending on the process and on other mineral sources used, different types of inorganic feed phosphates can be produced. The majority of the inorganic feed phosphates used in the EUEuropean Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
and worldwide are calcium phosphate
Calcium phosphate
Calcium phosphate is the name given to a family of minerals containing calcium ions together with orthophosphates , metaphosphates or pyrophosphates and occasionally hydrogen or hydroxide ions ....
s in different forms (mono-, di- and monodi-calcium phosphates) but also magnesium phosphate
Magnesium phosphate
Magnesium phosphate is a general term for salts of magnesium and phosphate appearing in three forms:* Magnesium phosphate monobasic * Magnesium phosphate dibasic * Magnesium phosphate tribasic...
s, sodium phosphates and even ammonium phosphate
Ammonium phosphate
Ammonium phosphate is the salt of ammonia and phosphoric acid. It has the formula 3PO4 and consists of ammonium cations and phosphate anion. It is obtained as a crystalline powder upon mixing concentrated solutions of ammonia and phosphoric acid, or on the addition of excess of ammonia to the...
s are used in animal nutrition
Animal nutrition
There are seven major classes of nutrients: carbohydrates, fats, fiber, minerals, protein, vitamin, and water.These nutrient classes can be categorized as either macronutrients or micronutrients . The macronutrients are carbohydrates, fats, fiber, proteins, and water...
. The end-product quality depends on the treatment and production process. Due to different chemical compositions of the different feed phosphate sources, large differences do exist in their phosphorus availability for the different animal species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
. However phosphate from the same source, produced by the same process, using the same raw materials, show consistent phosphorus availability, which can be measured in biological assays.
| Example of a calcium feed phosphate production Phosphoric acid is neutralized by means of calcium oxide Calcium oxide Calcium oxide , commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline crystalline solid at room temperature.... or – carbonate Calcium carbonate Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,... or a mixture thereof. Dicalcium phosphate: H3PO4 + CaO + H2O ↔ CaHPO4 + 2 H2O Monocalcium phosphate: 2H3PO4 + CaO + H2O ↔ Ca(H2PO4)2.H2O + H2O Or : Based on dicalcium phosphate Monocalcium phosphate: H3PO4 + CaHPO4 +2H2O ↔ Ca(H2PO4)2.H2O + H2O Depending on the used qualities the resulting product are more or less pure di- or monocalcium phosphates. |
Quality
Consistent phosphorus availability relies on strict quality controlQuality control
Quality control, or QC for short, is a process by which entities review the quality of all factors involved in production. This approach places an emphasis on three aspects:...
during the process, to avoid degradation of orthophosphate into other unavailable phosphate forms. Impurities which are naturally occurring in the used raw materials must also be considered. But also feed hygiene and good manufacturing
Manufacturing
Manufacturing is the use of machines, tools and labor to produce goods for use or sale. The term may refer to a range of human activity, from handicraft to high tech, but is most commonly applied to industrial production, in which raw materials are transformed into finished goods on a large scale...
practices should be complied with at all stages.
Phosphorus requirements
All animals require phosphorus and for most production animals these requirements are well established. Normally a number of variable factors such as performance level and breed differences are taken into account. On top of this, a safety margin is added to this to deal with variations within one flock or herd. Dietary allowances at the end take into account the availability of phosphorus within the diet and meet the requirements through supplementation with inorganic feed phosphates.In addition calcium and vitamin D
Vitamin D
Vitamin D is a group of fat-soluble secosteroids. In humans, vitamin D is unique both because it functions as a prohormone and because the body can synthesize it when sun exposure is adequate ....
levels must be optimized because phosphorus metabolism
Metabolism
Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...
is closely linked to these and symptoms of deficiency can be intensified if not taken into respect properly.
Preventing deficiencies
Because of possible phosphorus deficiencies in farmed animals, phosphorus is supplied in the form of inorganic feed phosphates. Consequences of deficiencies are known and well documented. The initial effect is a fall in blood plasmaBlood plasma
Blood plasma is the straw-colored liquid component of blood in which the blood cells in whole blood are normally suspended. It makes up about 55% of the total blood volume. It is the intravascular fluid part of extracellular fluid...
levels, followed by withdrawal of calcium and phosphorus from the skeleton. Loss of appetite and reduced productivity are common in all animal species. A poor feed conversion efficiency and a lowered live weight gain
Weight gain
Weight gain is an increase in body weight. This can be either an increase in muscle mass, fat deposits, or excess fluids such as water.-Description:...
are well known production related indicators. Other deficiency includes reduced fertility in cattle, but also reduced milk yield (milk contains on average 1 g of P per kg), stiffness and in extreme cases even enlarged joints or deformed bones and lameness. Other well known symptoms are In layers reduced egg yield and, in case of chicks, reduced hatchability, together with cage layer fatigue syndrome. Also for all species osteomalacia
Osteomalacia
Osteomalacia is the softening of the bones caused by defective bone mineralization secondary to inadequate amounts of available phosphorus and calcium, or because of overactive resorption of calcium from the bone as a result of hyperparathyroidism...
and reduced fertility are possible. All these symptoms are more or less irreversible, resulting in economical losses for the farmer.
Phosphorus metabolism
The mechanisms of phosphorus digestionDigestion
Digestion is the mechanical and chemical breakdown of food into smaller components that are more easily absorbed into a blood stream, for instance. Digestion is a form of catabolism: a breakdown of large food molecules to smaller ones....
and metabolism differ substantially between ruminant
Ruminant
A ruminant is a mammal of the order Artiodactyla that digests plant-based food by initially softening it within the animal's first compartment of the stomach, principally through bacterial actions, then regurgitating the semi-digested mass, now known as cud, and chewing it again...
and non-ruminant (monogastric
Monogastric
A monogastric organism has a simple single-chambered stomach, whereas ruminants have a four-chambered complex stomach. Examples of monogastric animals include omnivores such as humans, rats and pigs, carnivores such as dogs and cats, and herbivores such as Horses and rabbits. Herbivores with...
) species. In pig
Pig
A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...
s, most phosphorus is absorbed from the small intestine
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...
-jejunum
Jejunum
The jejunum is the middle section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms middle intestine or mid-gut may be used instead of jejunum.The jejunum lies between the duodenum...
, duodenum
Duodenum
The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms anterior intestine or proximal intestine may be used instead of duodenum...
- in the form of ortho-phosphate where its solubility is greatest. The phosphorus is then transported across the gut wall. The kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
plays the major regulatory role in controlling phosphorus levels, any excess is excreted primarily via the urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
. In poultry
Poultry
Poultry are domesticated birds kept by humans for the purpose of producing eggs, meat, and/or feathers. These most typically are members of the superorder Galloanserae , especially the order Galliformes and the family Anatidae , commonly known as "waterfowl"...
available phosphorus solubilises in the gizzard
Gizzard
The gizzard, also referred to as the ventriculus, gastric mill, and gigerium, is an organ found in the digestive tract of some animals, including birds, reptiles, earthworms and some fish. This specialized stomach constructed of thick, muscular walls is used for grinding up food; often rocks are...
where it becomes available for absorption also in the duodenum and jejunum.
Ruminants have a digestion system whereby micro-organisms in the rumen
Rumen
The rumen, also known as a paunch, forms the larger part of the reticulorumen, which is the first chamber in the alimentary canal of ruminant animals. It serves as the primary site for microbial fermentation of ingested feed...
produce enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
s breaking down and thereby making available phosphorus from plant material. Phosphorus from plant sources is therefore better suited to ruminants’ but is still utilized to a lesser extent than phosphorus provided by inorganic sources. The ruminant needs for phosphorus is dictated by the needs of the microbial population in the rumen, with the phosphorus being necessary for cellulose
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....
digestion and protein synthesis. The main source is phosphorus recycled by the saliva
Saliva
Saliva , referred to in various contexts as spit, spittle, drivel, drool, or slobber, is the watery substance produced in the mouths of humans and most other animals. Saliva is a component of oral fluid. In mammals, saliva is produced in and secreted from the three pairs of major salivary glands,...
, a peculiarity of ruminants’. Phosphorus is mainly absorbed in the small intestine and homeostasis
Homeostasis
Homeostasis is the property of a system that regulates its internal environment and tends to maintain a stable, constant condition of properties like temperature or pH...
is achieved by excretion
Excretion
Excretion is the process by which waste products of metabolism and other non-useful materials are eliminated from an organism. This is primarily carried out by the lungs, kidneys and skin. This is in contrast with secretion, where the substance may have specific tasks after leaving the cell...
of phosphorus with the faeces.
Phosphorus from other sources
The majority of the phosphorus in animal feedAnimal feed
Animal feed may refer to:*Compound feed, commercial pelleted food produced in a feed mill and fed to domestic livestock*Fodder, food given to domestic livestock, including plants cut and carried to them*Forage, growing plants eaten by domestic livestock....
s originates from the vegetal feed materials to compose these feeds. However, up to 80% of the phosphorus present in vegetal feed materials is in the form of phytate. Unfortunately, and in contrast to ruminants, poultry and pigs lack the enzyme necessary to break down this phytate-phosphorus. Therefore, phosphorus digestibility of plant phosphorus varies between 6% and 50%, and it is assumed that at least two thirds of the organic phosphorus in the diet is unavailable for pigs and poultry. That’s why normally phosphorus in the form of high quality inorganic feed phosphates has to be supplemented to diets of high producing farm animals.
Accurate nutrition
The key to answering the phosphate issue in animal feeding is to formulate dietDiet (nutrition)
In nutrition, diet is the sum of food consumed by a person or other organism. Dietary habits are the habitual decisions an individual or culture makes when choosing what foods to eat. With the word diet, it is often implied the use of specific intake of nutrition for health or weight-management...
s closer to the requirements. This can be carried out by, amongst others, the use of highly digestible feed materials including the use of high quality inorganic feed phosphates. High quality inorganic feed phosphates are supplemented to make up the deficit between requirements and allowances.