CHEMICALLY REACTIVE BINDER FOR ANIMAL FEED

Abstract: The present invention relates to a novel binder combination for pelletized and compressed animal feed. This binder comprises a chemically reactive mixture of a reactive phosphate source plus a reactive metal oxide, hydroxide, or salt.

Description: BACKGROUND OF THE INVENTION The present invention provides a novel binder combination for pelletized and compressed animal feed. This binder comprises a chemically reactive mixture of a reactive phosphate source plus a reactive metal oxide, hydroxide, or salt. In recent years, pelleted animal feed has become a dominant factor in feeding of both monogastric and ruminent animals. There are several advantages to feeding pelleted feeds: (1) pelleted feed prevents selective feeding on those ingredients in the formulation which are more palatable and thus more desirable to the animal; (2) pelleting of the feed ration prevents segregation of the varying size and density constituents which are inherent in animal feeds; (3) pelleting animal feed results in higher bulk density, which is advantageous for both shipping and handling, resulting in maximum load efficiency and reduced storage requirements; (4) pelleting also increases nutritional utilization of the feed components, thus increasing conversion rate of the feed formulation. Feed pelleting is, as commonly practiced, an extrusion type thermoplastic molding operation in which finely divided particles of a feed ration are formed into compact, easily handled pellets. To improve the strength and durability, and to reduce fines produced during the pelleting process, several feed binder additives have been recommended. One of the commonly used ingredients for such purpose is molasses. However, this product tends to reduce lubrication of the feed ingredients through the die of the pelleting equipment, resulting in decreased production rates and increased energy costs. Additional materials which have been recommended and used as binders, or binding agents, for pelleting animal feeds include clays, in particular bentonite clay and attapulgite clay, lignin sulfonates, a by-product of the paper pulping industry; and gums, such as natural cellulose gum combinations. In addition, such products as sodium carboxymethylcellulose have been used to increase pellet quality. The clays and lignin sulfonate products are normally employed as binding agents at rates of from 1.5 percent to 3.5 percent by weight. Nutrient value of such products, however, particularly the clays, is minimal, so considerable volume is used in the formulation with little or no contribution to nutritional value. Gums are normally used at much lower concentrations; in the range of 0.05 percent to 0.2 percent, by weight. However, the cost of such materials often precludes their use, particularly at higher, more effective concentrations. PCT Patent Application WO82/01463 describes animal feed blocks which consist essentially of finely divided calcium oxide and molasses. In an alternative embodiment this mixture can be used to bind granular feed particles into pellets by molding. US Patent US-A-4,160,041 describes the use of a combination of a metal oxide and a soluble phosphate to solidify liquid feed ingredients such as molasses. UK Patent GB-A-2,047,066 describes the use of alkali metal silicates as a binder in animal licking blocks or agglomerates. Phosphoric acid, magnesia and molasses are mentioned as optional ingredients. US Patent US-A-4,182,755 describes an animal feed composition containing a metal chloride. A phosphate is optionally present. UK Patent Application GB-A-2,063,255 describes, inter alia, extruded animal feed pellets comprising fermented ammoniated condensed whey and a calcium salt; this mixture can also be used as a binder for moulded blocks of animal feedstuffs. Phosphoric acid or ammonium polyphosphate may also be present. SUMMARY OF THE INVENTION The present invention provides an extrusion-pelletized animal feed composition comprising a mixture of solid feed ingredients and a binder therefor (said mixture optionally containing some molasses), said binder comprising a reaction product formed in the feed composition from 0.1 percent to 5.0 percent by weight of the total feed composition of a reactive phosphate source selected from phosphoric acid, ammonium polyphosphate, monoammonium phosphate, diammonium phosphate, monopotassium phosphate, dipotassium phosphate, monosodium phosphate, monocalcium phosphate, disodium phosphate, and combinations thereof, and from 0.25 percent to 5.0 percent by weight of the total feed composition of a reactive metal source selected from magnesium oxide, aluminum oxide, potassium oxide, calcium oxide, magnesium calcium oxide, magnesium hydroxide, aluminum hydroxide, potassium hydroxide, calcium hydroxide, calcium sulfate, magnesium potassium sulfate, magnesium sulfate, potassium sulfate, calcium chloride, magnesium chloride, magnesium carbonate, and combinations thereof. DESCRIPTION OF PREFERRED EMBODIMENTS Various preferred features of the invention will now be described. The chemically reactive feed binder composition of this invention is composed of a reactive phosphate source, which is phosphoric acid, ammonium polyphosphate, monoammonium phosphate, diammonium phosphate, monopotassium phosphate, dipotassium phosphate, monosodium phosphate, monocalcium phosphate, disodium phosphate, or combinations of the above, plus a reactive metal source. The reactive metal source is a reactive metal oxide selected from magnesium oxide, aluminum oxide, potassium oxide, calcium oxide and magnesium calcium oxide (dolime); or an hydroxide selected from magnesium hydroxide, aluminum hydroxide, potassium hydroxide, and calcium hydroxide; or a metal salt capable of reacting with a reactive phosphate, hereafter called "reactive metal salt", selected from calcium sulfate, magnesium potassium sulfate, magnesium sulfate, potassium sulfate, calcium chloride, magnesium chloride, calcium carbonate and magnesium carbonate; or combinations of such reactive salts, oxides, and hydroxides. Several factors concerning the phosphate source are important in utilizing the material as one component of this chemically reactive feed binder composition. The first such factor is purity of the phosphate material. The material should be an approved feed grade product and be of a purity level that will meet minimal feed grade requirements. Higher purity, such as technical grade or food grade, is also appropriate for such use and usually yields a higher concentration of the phosphate of choice, allowing use at proportionally lower concentrations. An additional factor important in the proper choice of phosphate material is particle size. Appropriate particle size can range from not greater than minus 16 mesh, U.S. Sieve Scale, and preferably not smaller than minus 325 mesh. The preferred size range is from 100 mesh to 325 mesh. The most reactive phosphate source for this invention is orthophosphoric acid as its rate of reaction with the other components of the feed binder is highest. Due to phosphoric acid's corrosive qualities and problems in handling, however, as well as considerations of introduction into the pelleting process, a solid form of reactive phosphate is most desirable. To this end, monoammonium phosphate offers the desirable reactive qualities and handling characteristics required. In addition, feed grade, technical grade and food grade forms of this material, suitable for animal feeding, are readily available. Although each of the previously listed solid phosphate sources is useful in developing a cohesive bond for animal feed pellets, the monoammonium phosphate represents the most cost efficient material choice, and is a recognized animal feed product. Monoammonium phosphate can be manufactured by the reaction of purified phosphoric acid with ammonia. The purified acid is obtained from two primary sources. Thermal or furnace acid is manufactured by burning molten white phosphorus in air and condensing the phosphorous pentoxide combustion gases in water. The second source of purified acid is from solvent extraction of phosphoric acid from impurities in wet process phosphoric acid. Wet process phosphoric acid is obtained by acidulation of apatite ore with sulfuric acid. A new process disclosed in U.S. patent US-A-4,325,927 teaches production of technical grade monoammonium phosphate directly from the reaction of impure wet-process phosphoric acid and ammonia. The phosphate source, expressed as phosphorus (P), is used in this invention at levels of from 0.10 percent, by weight, to 5 percent, by weight, of the total feed formulation. The most preferred levels of use are from 0.20 percent to 2.0 percent of the total feed formulation, expressed as P. The reactive metal oxide, hydroxide or reactive salt should be a material which is animal feed approved and which exhibits a particle size of from 16 mesh, U.S. sieve scale, to 325 mesh. The most desirable sizing is from 100 mesh, U.S. sieve scale, to 325 mesh. Of the reactive metal oxides, hydroxides and salts suitable for this invention, magnesium oxide and calcium oxide are most suitable, as they contain a high level of nutrient value, and when manufactured to proper specifications of surface area and sizing, offer a high degree of reactivity. A suitable high purity magnesium oxide, for purposes of this invention, is the product of reacting magnesium chloride solution, for example seawater or magnesium chloride brine, with lime (CaO) or dolomitic lime (MgO:CaO), to precipitate insoluble magnesium hydroxide which is then calcined to between 1200°F and 2100°F (between 649°C and 1149°C), usually in a multiple hearth or rotary kiln. This results in a magnesium oxide product with a B.E.T. surface area of between 10 square meters per gram and 120 meters square per gram. Alternatively, magnesium oxide with approximately the same surface area specifications can be produced commercially by calcining natural magnesite (MgCO₃). Calcium oxide is the product of calcination of calcitic limestone (CaCO₃). Calcitic limestone can be calcined by various methods. For example; in a shaft kiln, in an indirect gas fired kiln, in a mixed feed kiln, in a parallel flow regeneration kiln, or in a rotary kiln, usually at from 1600°F to 2100°F (871°C to 1149°C). The calcium oxide useful for this invention would exhibit a B.E.T. surface area from one square meter per gram to 2 square meters per gram. The amount of reactive metal oxide, hydroxide or salt which is utilized in the invention is from 0.25 percent to 5 percent, by weight, of the full feed formula expressed as the metal oxide. The most preferred level is from 0.5 percent to 2.0 percent, by weight, expressed as the metal oxide. The two components of the feed pellet binder system, the reactive phosphate source, and the reactive metal oxide, hydroxide, or reactive salt or combination of metal oxide, hydroxide and reactive salt, are admixed to obtain a uniform blend of materials. The ratio of phosphate, expressed as P, to the metal oxide, hydroxide, or reactive salt, expressed as the metal oxide, can range from 1:5 to 5:1. However, the most preferred ratio for this admixed combination is from 1:3 to 3:1 P to metal oxide. The blended ratio of phosphate source and reactive metal oxide, hydroxide or reactive salt, or combination, is then added to the total feed formulation prior to mixing and pelleting. Alternatively, the desired ratio of phosphate source to metal oxide source, hydroxide or equivalent metal salt, can be admixed separately into the entire feed formulation which is to be pelleted, providing that sufficient mixing is available to completely disperse the metal oxide, hydroxide or metal salt component, or combination, and the phosphate component, completely throughout the feed mixture prior to pelleting. In the feed pelleting process, various feed ingredients chosen from the list comprising, but not limited to, dehydrated alfalfa, barley, beet pulp, blood meal, brewers grain, buttermilk citrus pulp, coconut meal, corn, corn cob and meal, corn gluten feed, corn gluten meal, corn oil meal, cottonseed meal, distillers grain, distillers solubles, fish meal, hominy, kafir corn, kafir head chop, linseed meal, meat scrap, milo maize, milo head chop, molasses, oats, oat hulls, oat screening, peanut meal, rice bran, rice polishings, soybean meal, wheat, wheat-mids, wheat flour, wheat bran, whey, bone meal, urea, plus others are uniformly mixed. In addition, minerals and mineral supplements and various drug and drug combinations may also be incorporated. In the practical application and use of this invention, the novel chemically reactive feed binder combination is added to the formulation containing various ground feed ingredients, minerals, vitamins and drug additives. The complete mixture is usually blended in a ribbon mixer or vertical mixer in two or three ton batches. Each batch is then delivered to overhead bins above the pellet mill. The mixture of feed ingredients, or meal mixture, flows by gravity into a flow rate regulator called a feeder, which provides a constant feed rate to the conditioning chamber. In the conditioning chamber, the entire meal mixture is subjected to steam prior to the actual pelleting step. Most liquids which may be introduced into the formulation, such as molasses, are also added through the conditioning chamber. Steam conditioning supplies moisture for lubrication, and partly gelatinizes starches. Steam addition at this point in the process also aids in solubilizing the phosphate component and soluble salt component of this invention, thus increasing the rate of reaction of the binder components. The amount of total moisture which is contained in the feed mixture is normally raised to a level of from 12 percent to 16 percent, by weight, of the feed formulation, as a result of liquid and steam addition. The temperature of the mixture is raised by 50°F to 150°F (28°C to 83°C) above ambient temperature as a result of steam addition, which also increases the rate of reaction of the binder ingredients. Pelleting of the feed is next accomplished by gravity flow of the steam conditioned feed ingredients, now called mash, into the pellet mill die chamber. In the die chamber, usually two or three rollers push the softened mash through holes in a circular die. Typically, the hole diameter of these dies is 9/32 inch to 1/4 inch (7.15 to 6.35 mm). Knives positioned outside the die cut the densified pellet to proper length. Alternative die types may produce pellets of variable shapes including cubes, squares, and large diameter round pellets. Typically, the formed pellet temperature ranges from 150°F to 210°F (65.6°C to 98.9°C). Hot pellets are usually cooled by forced air through vertical cooling systems to near ambient temperature. By the use of the binder of this invention, namely the selected phosphate source in combination with at least one of the group consisting of metal oxides, hydroxides, or reactive metal salts, uniformly mixed with the feed prior to the steam conditioning step, a significant increase in pellet durability is attained. In addition, a significant reduction in fines, typically as measured from the pellet cooler after pelleting, is also attained. Although the entire mechanism of the invention is not fully understood, it is believed that the reactive phosphate source, when added at the levels specified above, exothermically reacts with the reactive metal oxide, hydroxide, or reactive salt, or combination thereof, when supplied as directed, to produce a metal phosphate cement-type compound which sets and strengthens the pellet, improves pellet durability, and reduces fines. For example, in the particular instance of the binder being comprised of magnesium oxide and monoammonium phosphate, the resulting cohesive bond is thought to be primarily magnesium ammonium phosphate. It is also possible that the reactive phosphate under particular feed conditions additionally reacts with other components of the total feed formulation which may become soluble during steam addition and thus available for reaction to complement the primary cohesive binding of the described invention. The scope of the disclosed invention, however, does not depend upon such additional, or secondary reaction, to be fully effective. An additional significant aspect of this invention is the feed nutrient value which is contained in the chosen binder ingredients. Phosphate, for example, is a widely recognized essential element for proper nutrition in a variety of animal feeding programs. Providing phosphate from a source which is both chemically reactive for feed binding purposes and, at the same time, available as a feed nutrient, eliminates the necessity of adding an additional phosphate source for nutrient value only, such as, traditionally, dicalcium phosphate or defluorinated phosphate. In the same vein, oxides, hydroxides and salts as used in this binder provide such needed minerals as magnesium, sodium, potassium and calcium for nutrition, as well as providing the reactive metal component to assure proper binding ability. EXAMPLE I The following dairy concentrate was prepared by mixing in a horizontal ribbon mixer for three minutes. No pellet binding agent was added. Formulation 1. Percent Grain Sorghum 47.55 Soybean Meal 22.25 Wheat Bran 25.00 Limestone 1.00 Salt 0.5 Dicalcium Phosphate 2.7 Vitamin Premix 1.0 100.0 The prepared meal was pelleted through a 1/4 X 1-1/2 inch (6.35 x 38.1 mm) pellet die. Pellets were collected and cooled to ambient temperature. A Pellet Durability Index (PDI) value was determined by tumbling 500 grams of sample for 10 minutes at 50 RPM in a dust tight enclosure. The testing enclosure consists of an enclosed box 12 inches (30.5 cm) on a side by 5 inches (12.7 cm) deep rotated about an axis which is perpendicular to and centered on the 12 inch (30.5 cm) sides. A 2 inch (5.08 cm) by 9 inch (22.9 cm) angle iron is positioned along one of its 9 inch (22.9 cm) sides to a diagonal of one of the 12 inch (30.5 cm) by 12 inch (30.5 cm) sides of the enclosure. A door placed in one of the sides of the enclosure is convenient for introducing and retrieving sample. To provide additional stress to the pellets being tested, five 5/8 inch (15.9 mm) size plated steel hex nuts were added to the pellets before tumbling. After tumbling, fines were determined by screening the sample on a wire sieve with openings just smaller than the nominal pellet diameter. The whole pellets remaining were weighed and a durability value calculated as follows: A similar formulation was also prepared, substituting phosphoric acid for the phosphate source of Formulation 1, and magnesium oxide added to the specification as stated above. Additional limestone was also added to complete the calcium requirement. Formulation 2. Percent Grain Sorghum 45.25 Soybean Meal 22.25 Wheat Bran 25.00 Limestone 2.87 Salt 0.5 Vitamin Premix 1.0 Phosphoric Acid 2.3 Magnesium Oxide 0.86 100.0 Both a pellet durability determination and a recycle fines determination were made on each of these formulations as reported below: Pellet Durability Index (PDI) Percent Recycle Fines Formulation 1 85.6 4.2 Formulation 2 93.8 3.0 PDI values exhibited a 9.6 percent increase in pellet durability for Formulation 2 in which the chemically reactive binder ingredients were used, compared to Formulation 1, in which no binder addition was used. Fines were also reduced by 28.5 percent in Formulation 2 compared to Formulation 1. EXAMPLE II Under plant conditions, six tons of each of the following dairy formulations were mixed and pelleted. In Formulation 4, monoammonium phosphate of the specification described above, and magnesium oxide of the specification described above, were substituted for the bentonite clay binder addition of Formulation 3. Formulation 3. Percent Corn 15.68 Peanut Meal 5.5 Wheat Middlings 45.0 Gluten Feed 5.0 Molasses 5.0 Dry Distillers Grain 2.5 Bentonite 2.5 Limestone 2.5 Barley 5.0 Soy 4.62 Calf Manna 2.5 Magnesium Oxide 0.25 Magnesium Potassium Sulfate 1.25 Soda 1.25 Aurocrumbs 0.175 Ruminent Premix 0.5 Mixing Salt 0.75 Ruminent Trace Mineral 0.25 100.0 Formulation 4. Percent Corn 15.68 Peanut Meal 5.5 Wheat Middlings 46.3 Gluten Feed 5.0 Molasses 5.0 Dry Distillers Grain 2.5 Monoammonium Phosphate 0.95 Magnesium Oxide 0.5 Limestone 2.5 Barley 5.0 Soy 4.62 Calf Manna 2.5 Magnesium Potassium Sulfate 1.25 Soda 1.25 Aurocrumbs 0.175 Ruminent Premix 0.5 Mixing Salt 0.75 Ruminent Trace Mineral 000.25 100.0 Manufactured pellets were sampled from tile cooler for each six ton run and Percent Durability Index values and percent recycle fines from the cooler were determined as outlined in Example I above, except that 10 hexhead 5/8 inch (15.9 mm) steel nuts were used to supply additional stress to the pellets during tumbling. Percent Durability Index (PDI) Percent Recycle Fines Formulation 3 84.2 1.92 Formulation 4 91.3 .66 PDI values for this comparative example exhibit an increase in pellet durability of 8.4 percent for Formulation 4 with the reactive binder of this invention compared to Formulation 3 with bentonite clay at 2.5 percent as a binder. Recycle fines were reduced by 65.6 percent in Formulation 4, compared to Formulation 3. EXAMPLE III Under plant conditions, eight tons of each of the following 20 percent protein high energy dairy formulations were mixed and pelleted. In Formulation 6, monoammonium phosphate of the specification described above, and magnesium oxide also described above, were substituted for a lignin sulfonate based binder additive of Formulation 5, as well as replacing most of the defluorinated phosphate. Additional limestone was also added to balance the calcium. Formulation 5. Percent Wheat Middlings 6.36 Molasses 3.5 Corn 46.75 Soybean Meal 23.25 Defluorinated Phosphate 2.0 Salt 0.75 Limestone 1.75 Magnesium Potassium Sulfate 0.85 Dairy Flavor 0.04 Corn Distillers Grain 2.5 Lignin Sulfonate 2.0 Peanut Meal 5.0 Barley 5.0 Mineral Premix 0.25 100.0 Formulation 6. Percent Wheat Middlings 7.13 Molasses 3.5 Corn 46.75 Soybean Meal 23.25 Defluorinated Phosphate 0.61 Salt 0.75 Limestone Ground 2.92 Magnesium Potassium Sulfate 0.85 Dairy Flavor 0.04 Corn Distillers Grain 2.5 Magnesium Oxide 0.5 Monoammonium Phosphate 0.95 Peanut Meal 5.0 Barley 5.0 Mineral Premix 0.25 100.0 Manufactured pellets were sampled from the cooler for each eight ton run and Percent Durability Index values and percent recycle fines from the cooler were determined as outlined in Example I above, with ten hexhead 5/8 inch (15.9 mm) steel nuts used to supply additional stress to the pellets during tumbling. Percent Durability Index (PDI) Percent Recycle Fines Formulation 5 73.2 2.01 Formulation 6 84.1 1.02 PDI values for this comparative example, using a lignin sulfonate based binder in Formulation 5 compared to a reactive phosphate and magnesium oxide binder of this invention in Formulation 6, exhibit an increase in pellet durability of 14.9 percent for Formulation 6. Additionally, fines were reduced in Formulation 6 by 49.2 percent. EXAMPLE IV Under plant conditions, six tons of each of the following 20 percent protein high energy dairy formulations were mixed and pelleted. In Formulation 8, monoammonium phosphate and magnesium oxide were substituted for the binder combination of bentonite clay and Pel-Aid "M" (manufactured by Rhodia Inc.) of Formulation 7. Most of the defluorinated phosphate was also replaced. Additional limestone was added to balance the calcium. Formulation 7. Percent Wheat Middlings 7.46 Molasses 3.50 Corn 46.75 Soybean Meal 23.25 Defluorinated Phosphate 2.00 Salt 0.75 Limestone 1.75 Magnesium Potassium Sulfate 0.85 Dairy Flavor 0.04 Corn Distillers Grain 2.50 Pel-Aid "M" 0.05 Bentonite Clay 0.85 Peanut Meal 5.0 Barley 5.0 Mineral Premix 0.25 100.0 Formulation 8. Percent Wheat Middlings 7.13 Molasses 3.5 Corn 46. 75 Soybean Meal 23.25 Defluorinated Phosphate 0.61 Salt 0.75 Limestone 2.92 Magnesium Potassium Sulfate 0.85 Dairy Flavor 0.04 Corn Distillers Grain 2.5 Monoammonium Phosphate 0.5 Magnesium Oxide 0.95 Peanut Meal 5.0 Barley 5.0 Mineral Premix 0.25 100.0 Manufactured pellets were sampled from the cooler for each six ton run and Percent Durability Index values and percent recycle fines from the cooler were determined as outlined in Example I above, with ten hexhead 5/8 inch (15.9 mm) steel nuts used to supply additional stress to the pellets during tumbling. Percent Durability Index (PDI) Percent Recycle Fines Formulation 7 73.7 2.30 Formulation 8 87.5 1.31 PDI values for this comparative example, using bentonite clay and Pel-Aid "M" as binders in Formulation 7 compared to a reactive phosphate and a reactive magnesium oxide binder in Formulation 8, exhibit an increase in pellet durability of 18.7 percent in Formulation 8. Additionially, fines were reduced in Formulation 8 by 43.0 percent. EXAMPLE V Under plant conditions, a minimum of two tons of each of the following 22 percent protein dairy formulations were mixed and pelleted. In Formulation 10, monoammonium phosphate and magnesium oxide as described were substituted for bentonite clay and Benti-Boost (manufactured by Hess & Clark) of Formulation 9. In addition, the monoammonium phosphate replaced all of the defluorinated phosphate of Formulation 9. Additional limestone was added to Formulation 10 to balance the calcium. Formulation 9. Percent Wheat Middlings 7.5 Soy Meal 30.6 Potassium Chloride 1.5 Peanut Meal 5.0 Limestone 2.5 Defluorinated Phosphate 1.5 Ruminent Premix 1.0 Salt 1.25 Corn 32.55 Barley 10.0 Sodium Bicarbonate 1.25 Magnesium Potassium Sulfate 0.25 Bentonite 2.5 Benti-Boost 0.1 Molasses 2.5 100.0 Formulation 10. Percent Wheat Middlings 7.5 Soy Meal 32.25 Potassium Chloride 1.5 Peanut Meal 5.0 Limestone 3.5 Ruminent Premix 1.0 Salt 1.25 Corn 32.55 Barley 10.0 Sodium Bicarbonate 1.25 Magnesium Potassium Sulfate 0.25 Monoammonium Phosphate 0.95 Magnesium Oxide 0.5 Molasses 2.5 100.0 Manufactured pellets were sampled from the cooler for each run and Percent Durability Index values and percent fines from the cooler were determined as outlined in Example I above, with ten 5/8 inch (15.9 mm) plated steel hexnuts used to supply additional stress to the pellets during tumbling. Percent Durability Index (PDI) Percent Recycle Fines Formulation 9 81.8 .74 Formulation 10 88.3 .69 PDI values for this comparative example using bentonite clay and Benti-Boost as binders in Formulation 9 compared to a reactive phosphate and reactive mangesium oxide binder of this invention in Formulation 10, exhibit an increase in pellet durability of 7.9 percent in Formulation 10, with fines from the cooler remaining essentially the same for both formulations. It will be seen that the present invention provides a chemically reactive feed binder composition which exhibits superior bonding strength, and improves pellet quality in a wide variety of feed pelleting formulations, which at the same time provides nutrient value in the animal feed formulations. Recycle fines normally produced during pelleting are also significantly reduced. While a common method for pelleting of animal feed is described above, it is understood that this invention also applies to other methods of extruding feed materials.

Claims: An extrusion-pelletized animal feed composition comprising a mixture of solid feed ingredients and a binder therefor, said binder comprising a reaction product formed in the feed composition from 0.1 percent to 5.0 percent by weight of the total feed composition of a reactive phosphate source selected from phosphoric acid, ammonium polyphosphate, monoammonium phosphate, diammonium phosphate, monopotassium phosphate, dipotassium phosphate, monosodium phosphate, monocalcium phosphate, disodium phosphate, and combinations thereof, and from 0.25 percent to 5.0 percent by weight of the total feed composition of a reactive metal source selected from magnesium oxide, aluminum oxide, potassium oxide, calcium oxide, magnesium calcium oxide, magnesium hydroxide, aluminum hydroxide, potassium hydroxide, calcium hydroxide, calcium sulfate, magnesium potassium sulfate, magnesium sulfate, potassium sulfate, calcium chloride, magnesium chloride, magnesium carbonate, and combinations thereof. A composition as set forth in claim 1, wherein the reactive phosphate source is present in a concentration of from 0.2 percent to 2.0 percent of the total feed composition, expressed as phosphorus. A composition as set forth in claim 1 or 2, wherein an amount of reactive metal oxide, hydroxide, or salt is utilized which is from 0.5 percent to 2.0 percent by weight of the total feed composition, expressed as metal oxide. A composition as set forth in any preceding claim, wherein the reactive phosphate source is phosphoric acid or monoammonium phosphate. A composition as set forth in any preceding claim, wherein the reactive metal source is selected from magnesium oxide, calcium oxide, magnesium potassium sulfate, and mixtures thereof. A composition as set forth in any preceding claim, wherein the ratio of phosphate source to reactive metal source is from 1:5 to 5:1. An animal feed composition as set forth in claim 1, wherein said binder comprises a reaction product formed in the feed composition from 0.20 to 2.0 percent by weight of the total feed composition of phosphoric acid, and from 0.5 to 2.0 percent by weight of the total feed composition of a reactive metal source selected from magnesium oxide, calcium oxide, magnesium potassium sulfate, and mixtures thereof. An animal feed composition as set forth in claim 1, wherein said binder comprises a reaction product formed in the feed composition from 0.20 to 2.0 percent by weight of the total feed composition of monoammonium phosphate, and from 0.5 to 2.0 percent by weight of the total feed composition of a reactive metal source selected from magnesium oxide, calcium oxide, magnesium potassium sulfate, and mixtures thereof. An animal feed composition as set forth in any preceding claim, wherein said composition further comprises a mineral, a vitamin, a drug additive, or a combination thereof.

Inventors: VAN DE WALLE, RICHARD H.
Applicants: MARTIN MARIETTA MAGNESIA SPECIALTIES INC
Application year: 1987
Main classification: A23K1
IPC codes: A23K1