WO2013103648A1 - A high energy rumen inert feedstuff - Google Patents

Abstract

The invention discloses a new method for making a rumen-inert feed additive that may be used alone, as an additive, as a pre-mix or as top dress. The method produces a high energy, rumen-inert feedstuff through a simple two-step process of first, combining one or more unsaturated fats that are substantially free of fatty acids with a fat-soluble acid comprising a carboxyl group to form a generally homogenous mixture, and, second, adding an alkali metal source capable of reacting with said carboxyl group to form a salt. When the alkali metal source is added, an exothermic reaction occurs which dissipates moisture. The reaction produces a friable, substantially insoluble solid with a density higher than water.

Description

A HIGH ENERGY RUMEN INERT FEEDSTUFF

BACKGROUND

[0001] The invention(s) relates primarily to feedstuff for animals, and in particular to feedstuff for ruminant animals.

[0002] The energy balance in a dairy cow is important to milk production. Unfortunately, a lactating dairy cow is in negative energy balance for the first 8-12 weeks of lactation as the cow's body attempts to meet all the energy requirements of milk production on top of her maintenance requirements. A negative energy balance is not ideal, but it is typical due to the genetics for high levels of milk production in the modern dairy cow. The negative energy balance results in weight loss and associated metabolic responses such as ketone accumulation in plasma. This negative balance also leads to more difficulty in re-breeding along with difficulty in optimizing potential milk production.

[0003] Increasing intake of total metabolizable energy by a dairy cow can be accomplished by increasing dry matter intake or by increasing energy density of the diet. In a typical dairy cow, dry matter intake is usually already at a maximum as many such cows are allowed to eat ad- libitum (all they can eat). Therefore, the only way to increase total intake of energy is to increase the energy density of the diet. Energy density can be increased by including more grain and less forage in the diet. However, there is a limit to the percentage of grain that can be incorporated into the total diet. Too much grain and starch can lead to rapid fermentation followed by lactic acid accumulation and a condition known as rumen acidosis. Increased fat content of the diet may increase milk production but if the fat content is too high, there will be toxicity related to the microorganisms in the rumen. These microorganisms otherwise digest fiber. Therefore, fat content that is too high reduces energy delivered by the diet. [0004] Two common feed ingredients used by dairymen to increase diet energy density are rumen-inert fat and calcium propionate. Rumen inert fats include lipogenic nutrients which can be bypassed through the rumen (i.e. escape fermentation in the rumen) and pass into the lower intestine for absorption. Calcium propionate provides gluconegenic precursors in the rumen. These precursors assist in balancing and/or replenishing glucose levels. These two metabolic pressures must be balanced in order to reduce or negate energy imbalance and related disease states. One example of a feed stuff that purports to solve the problem is disclosed in U.S. Pat. No. 5,660,852. The '852 teaches a feed supplement for ruminants toprevent nutrient imbalance. The feed supplement comprises 10% - 40% gluconegenic compound (e.g. propionic acid) and 10% - 40% C14-C22 hydrogenated fatty acid which is rumen inert.

[0005] There are three methods of producing rumen-inert fats: increasing fat saturation; forming a calcium salt with free fatty acids; and by encapsulation of fats to create a physical barrier to prevent interaction with rumen microbes.

[0006] Increasing the saturation of fat requires complicated processing using hydrogen, a catalyst and a reaction vessel. Further, saturation of triglycerides reduces their intestinal digestibility.

[0007] Therefore, calcium salts of free fatty acids are a preferred rumen inert fat source. However, calcium salts require an additional initial step of hydrolysis of triglycerides to obtain the free fatty acids. Additionally, they are well known to decrease dry matter intake when fed at the higher end of recommended levels. This is counterproductive to inclusion of a high energy feed ingredient to the total diet.

[0008] Encapsulated fats or oils have been produced and shown to be efficacious in live animals. Oils are typically encapsulated with amines or highly hygrogenated fats, for example. However, encapsulated fats or oils have not been able to be produced economically enough to gain commercial use.

[0009] Glucose is essential for milk synthesis and can be limiting. The primary source of glucose in ruminants is from propionic acid produced in the rumen and later converted to glucose in the liver. Increasing the amount of starch in the diet can increase propionate production, but too much carbohydrate can also lead to rumen acidosis. Feeding propionic acid, usually as its calcium salt, is one method to increase propionate supply and subsequent glucose production in ruminants. However, calcium propionate is not very palatable and can cause a decrease in feed intake. Further, it is readily soluble and will volatilize when mixed with wet feed ingredients, especially in hot summer-time conditions.

[0010] Calcium will not react with intact triglycerides; therefore, adding calcium source to the oil will not result in rumen protection of these oils. Calcium does readily form a salt with propionate but it is very highly soluble in water. The highly soluble salt dissociates when combined with wet feedstuffs and is prone to volatilization. Further, propionate may be metabolized in the rumen. Therefore, less than 100% of the propionate fed as calcium propionate to a ruminant is utilized as an actual glucogenic precursor.

[0011] Accordingly, there is a need for a high energy rumen inert feedstuff that combines glucose precursors and oil.

[0012] Further there is a need for a rumen-inert fat with high digestibility and palatability that doesn't reduce dry matter intake.

[0013] Further there is a need for a less soluble calcium propionate that is less volatile and more palatable when mixed into wet feedstuffs. [0014] Further there is a need for a high energy feedstuff that is simple to manufacture and that canbe fed to both ruminant and nonruminant animals.

[0015] Further there is need for a high energy rumen inert feedstuff that is simple to manufacture. SUMMARY

[0016] Accordingly, a method to produce a high energy feedstuff for ruminants and nonruminants is disclosed. The method includes process steps and a small number of component materials. The components comprise unsaturated oil preferably substantially free of fatty acids, more preferably between 0% and about 10% free fatty acids, the unsaturated oil being of vegetable, animal, or marine origin, a carboxylic acid and an alkali metal source. The process results in a product comprising rumen inert properties and a feedstuff delivering a high energy level.

[0017] The present invention provides an economical method to produce a high energy, rumen inert feedstuff for ruminants and other animals comprising a novel method of combining generally known ingredients. The high energy rumen inert feedstuff is simple to manufacture. Further, the present invention provides a method to produce a non-volatile source of glucogenic propionate that is stable when mixed into and with wet feedstuffs in totally mixed rations. The method provides a less soluble alkali propionate source that is less volatile and more palatable when mixed into wet feedstuffs than other feedstuff or additives made with propionic or other carboxylic acids. Further, the present invention provides a high energy feedstuff that substantially homogenously combines a fat source or oil and a glucogenic precursor for ruminants. The feedstuff disclosed provides a high energy feedstuff for non-ruminant animals and provides a rumen-inert fat with high digestibility and palatability that does not reduce dry matter intake in ruminant animals. Finally, the process steps include an exothermic reaction, and are preferably conducted without addition or use of an aqueous medium. Due to the heat produced by the exothermic reaction the process results in a product which is friable or granular in nature without the need for additional drying steps, or which may be dried to the requisite levels using only minimal resources. The product is highly stable at typical storage temperatures and may be employed as a feed additive (herein used interchangeably with "supplement") mixed with feed prior to delivery to the feeding location or at the feeding location, either delivered as feed, as a premix, or as a top dress product. DETAILED DESCRIPTION

[0018] As described herein, a rumen inert, high energy feedstuff is produced. The method generally includes mixing an unsaturated fat with a carboxylic acid into a homogenous, acid-oil solution and then admixing a source of an alkali metal ion to react with the acid-oil solution and result in the formation of a substantially solid, digestible compound.

[0019] The unsaturated oil or fat used in the method may be any triglyceride fat (neutral oil) or mixture of triglycerides, diglycerides, monoglycderides and with free fatty acids. The fat source preferably comprises a mono-unsatured or poly-unsaturated oil, substantially free of fatty acids, unsaponified, of vegetable, animal or marine origin. The fat source preferably has a melting temperature between about -75°C to 50°C, more preferably from about -25°C to about 10°C. Preferably, the fat source is of vegetable origin. More preferably, the fat source is a neutral oil from corn, soybean, canola, cottonseed, palm, peanuts or other vegetable oils where said commodities are compatible for use with the methods and material described herein, and their processing without departing from the overall scope of the present invention. Even more preferably, the fat source is crude oil resulting from processing of oilseed or cereal grains to produce oil. Even more preferably, the crude oil may be recovered corn oil from a corn ethanol byproduct such as corn ethanol whole stillage or corn ethanol thin stillage. The fat source is preferably substantially free of fatty acids, more preferably the fat source contains less than about 15% fatty acids, and most preferably contains less than 10% free fatty acids.

[0020] The acid source may be any fat soluble carboxylic acid capable of forming a homogeneous mixture with the fat source. For example, but without limitation, propionic acid, butyric acid, valeric acid, iso-butyric acid, iso-valeric acid are acceptable acids. The acid source may be any feed grade source or one of higher purity suitable for inclusion in livestock feedstuffs. The preferred fat soluble carboxylic acid is propionic acid. Its acid content may range from about 50 to about 100% on a weight basis. More preferably the propionic acid content may range from about 80 to about 100% on a weight basis.

[0021] The alkali metal source may be any feed grade source capable of reacting with the acid carboxyl group to form a salt, particularly but not limited to calcium, magnesium, and barium, preferably calcium or magnesium, and most preferably calcium. The metal source may be any feed grade source or one of higher purity or grade suitable for inclusion in livestock feedstuffs that is capable of reacting with propionic acid to form a salt. Where calcium is the metal source, one is chosen from a group comprising, for example, calcium hydroxide, calcium oxide, or dolomitic lime, calcium chloride, calcium sulfate, calcium carbonate. More preferably, the calcium is either calcium hydroxide or calcium oxide.

[0022] The fat source is firstly mixed with the acid source until the two ingredients form a homogenous acid-oil solution or mixture. The liquid should be stirred or agitated and there should be no visible layer of glycerol. The mixing does not result in hydrolysis of the fat and release of free fatty acids. The ratio of triglyceride to acid is from about 10:90 to about 90: 10, more preferably about 25:75 to about 75:25 most preferably 10:40 to 60:40. The weight % of fat in the total acid-oil mixture may range from about 10 to about 90%, more preferably from about 25 to about 75%, and even more preferably from about 40 to about 60%. [0023] Secondly, the metal source is added while agitation is applied to the substantially homogenous mixture of fat and acid. Metal is added to equal from about 10 to about 90 wt. % of the final product weight, more preferably from about 25 to about 75 wt. %, and even more preferably from about 40 to about60 wt. %. An exothermic reaction ensues whilst the metal reacts with the acid to form a salt. Upon mixing, the metal and acid-oil form a paste. Good and thorough mixing is important and can be accomplished using any conventional mixer capable to hold the liquid acid-oil mixture and fold in the metal source. Allowed to react further the paste hardens and solid crystals are formed. The reaction-mixing vessel is preferably open-top to allow heat and moisture dissipation from the reacting feedstuff. The reaction temperature may reach up to about 200°C, but preferably the reaction is controlled to not exceed about 150°C. The metal source is preferably added all at once or in smaller amounts during a period of up to about 30 minutes.

[0024] In an example embodiment, corn oil recovered as a byproduct of ethanol production is combined with propionic acid in a 40 to 60 ratio to form a generally homogenous mixture, without any visible layer of glycerol. No heat is observed to be produced, and no major chemical reaction has taken place. Next, Ca(OH)2 is added in small amounts for a total ratio of 40% calcium source to the total product weight. The addition of the Ca(OH)2 is accomplished over a period of about 10 minutes, with the reaction generating heat and dissipating moisture and resulting in a friable substance, easily granulated.

[0025] The reaction disclosed herein surprisingly converts the fat source from an oil to a solid fatty product with a density greater than water. The addition of either ingredient, acid or metal, to the fat source individually does not result in any reaction as the fat is a neutral oil and generally unreactive. The metal and acid mixed together (without oil) will readily form a salt in an exothermic, acid-alkali reaction. However, it is known that these salts are very soluble and dissociate easily in solution. While not desiring to be bound by any one theory, it is hypothesized that the reaction of the present invention between the alkali metal such as calcium, and the carboxylic acid such as propionic acid is binding the fat in some way into an alkali- carboxylic-fat or, more particularly in one example, a calcium-propionate-fat compound or product.

[0024] Having generally described this invention, a further understanding can be obtained by reference to another example provided herein for purpose of illustration only and not intended to limit the scope of the invention unless otherwise specified.

EXAMPLE

[0025] Two feedstuffs were prepared according to Table 1.

Table 1. Feedstuff composition.

Sample ID

Ingredient 1 2

Fat source 1 : Corn oil, food grade - Mazola brand 50grams

Fat source 2: Canola oil, food grade 50grams

Propionic acid, 85% 50grams 50grams

Calcium hydroxide 50grams 50 grams

[0026] Each fat source was first mixed with propionic acid until homogenous. No separation was observed, suggesting there was no acid catalyzed hydrolysis of the

triglycerides. Secondly, calcium hydroxide was mixed into each propionic acid/fat mixture. The total mixture quickly generated heat and solidified within a few minutes. [0027] A test was conducted to evaluate the solubility and fat density of each product. Each product was added to 75 grams of water to equal approximately 1 and 1 1% of the total weight. Samples were stirred for 2.5 hours at about 200rpm. One ml of each soluble fraction was collected for analyses of propionic acid content. They were then transferred into 50ml centrifuge tubes and centrifuged at 1 ,500 X g for 10 minutes. After centrifuging, the liquid layer was decanted into pre-weighed glass beakers and dried in a 100°C oven until weight loss stabilized. The remaining solids represent anhydrous material that is less dense than water. Calcium propionate is readily soluble in water and it was theorized that, if present, it should be recovered 100% in the soluble fraction. Fat is lighter or less dense than water and it was theorized that any remaining fat should be 100% recovered by decanting the top portion of each sample, including some water, and drying to remove moisture.

Table 2. Solubility of feedstuffs.

Sample ID

1 1 2 2

Grams of sample/75 g water 0.981 10.066 0.996 10.019

Grams oil in sample 0.324 2.824 0.279 2.810

Grams recovered in supernatant 0.052 0.456 0.397 3.731

Oil recovered as lighter than

15.97 13.72 120.85 1 12.84

water, %

Propionic acid added to water

3,593 32,824 3,673 32,992

from sample, ppm

Propionic acid recovered in

131 289 217 292

soluble fraction, ppm

Propionic acid recovery, % 3.65 0.88 5.90 0.88

[0028] Both products 1 and 2 were observed as being highly insoluble in water. Product 1, made with corn oil, did not cloud or create any turbidity in the water even after 2.5 hours of stirring. Stirring product 2 for 2.5 hours resulted in some turbidity or suspended solids that clouded the water. These did not separate down with centrifuging and resulted in a high 'recovery of fat' for product 2 using the method described above. In Product 1, nearly all the solid material was denser than water and formed a pellet on the bottom of the centrifuge tubes. Propionate recovery was low for both Product 1 and 2. Calcium propionate is readily soluble in water. Therefore, it is believed that the propionic acid formed a type of insoluble, denser than water, complex with corn oil (Product 1) when mixed with calcium hydroxide. The higher Oil recovery' in Product 2 coupled with low propionic acid recovery suggests formation of a similar but unique compound that reduces solubility of propionic acid, but which isn't as dense as the one formed with corn oil. In both cases, the unsaturated oils in the form of triglycerides were altered in density during product formation and are believed to be good sources of rumen inert fat.

[0030] The product was next tested to determine whether the fat content was rumen inert and inert to what degree. The protocol for this test involved extracting rumen fluid from an animal and introducing the product to the rumen fluid in a C02 environment. The product was divided into a number of small micron bags and exposed to the fluid. After predetermined exposure times, the bags were dried and the materials remaining were measured for calcium and fat to determine the amount of each remaining base component. The results are presented below:

Table 2. Recovery of base components over time in rumen fluid.

Corn oil, Fat CaOH2 Propionic Acid

4 hrs 102% 71% 49%

8 hrs 105% 59% 57%

12 hrs 102% 57% 61%

24 hrs 100% 54% 37%

30 hrs 96% 52% 33%

72 hrs 89% 53% 29%

[0031] The data demonstrate the stability of the fat in the product through 30 hrs in rumen fluid, and good maintenance through 72 hrs. The Ca(OH)2 and propionic acid are each measurably reduced more rapidly than the fat in the rumen fluid.

[0032] Formation of this rumen inert fat and energy supplement does not require the use of free fatty acids. Advantageously, triglycerides can be utilized which reduces processing costs. In addition, production is accomplished very simply and requires only mixing the ingredients together in the proper order. Most often, by employing the correct ratios of reactants and using equipment that allows steam to dissipate readily, the reaction provides adequate heat to result in moisture removal from the final product which may be easily granulated. However, certain ratios are less likely to provide adequate heat, and some equipment may not adequately allow dissipation of steam moisture in which case, the product may be dried to the degree necessary or desired for the final use of the product.

[0033] The reaction may be conducted under cooler conditions; at cooler conditions the fat will crystallize in a different manner which will effect the bioavailability of the fat.

Adjusting temperature in this way allows the method to be tailored to create different variations of the product as it relates to bioavailability. Further, the ratios of ingredients may be changed. For example, higher levels of fat may produce a product that is less stable in the rumen while lower levels of fat will produce a product more stable in the rumen.

[0034] The product is to be fed to animals, both ruminants and nonruminants. It may be stored in regular 25 kilo bags, or other containers of various sizes, at room temperature and up to about 40°C to about 60°C. The product may be used as a top dress for feed, as a feed additive, as a premix to the feed or to be combined with feed before feeding, or added directly to the diet. The product's form may be granulated, or pelletized with or without feed.

[0035] Several embodiments of the invention and many of its improvements have been herein described with a degree of particularity. The previous description is of preferred examples for implementing the invention, and the scope of the invention should not necessarily be limited by this description. Although various representative embodiments of this invention have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of the inventive subject matter set forth in the specification and claims.

[0036] As utilized herein, the terms "approximately," "about," "substantially", and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the invention as recited in the appended claims.

[0037] It is also important to note that the construction and arrangement of the products and the methods as described in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, temperature conditions, reaction vessel variations, selection of fat source, metal source, and acid sources, and combinations of multiple fat sources and/or multiple acid sources in a single reaction are within the purview of this disclosure and one of ordinary skill in the art) without materially departing from the novel teachings and advantages of the subject matter recited. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the various examples of embodiments without departing from the spirit or scope of the present inventions.

Claims

What is claimed is:

1. A method to produce a high energy, rumen-inert feedstuff for ruminant and nonruminant animals comprising combining one or more unsaturated fats and a fat-soluble acid comprising a carboxyl group to form a generally homogenous mixture, and adding to said mixture an alkali metal source capable of reacting with said carboxyl group to form a salt.

2. The method of claim 1 wherein the one or more unsaturated fats comprise

unsaturated oils substantially free of fatty acids.

3. The method of claim 2 wherein each of said one or more unsaturated fats comprises a melting temperature between about -75°C and about 50°C.

4. The method of claim 1 wherein at least one of said one or more unsaturated fats is of

vegetable origin.

5. The method of claim 1 wherein said one or more unsaturated fats each comprise less

than about 15% fatty acids.

6. The method of claim 1 wherein said carboxylic acid is selected from the group

consisting of propionic acid, bubyric acid, valeric acid, iso-butryic acid, and iso- valesic acid.

7. The method of claim 1 wherein said alkali metal source comprises one selected from

the group consisting of calcium, magnesium, and barium.

8. The method of claim 1 wherein said alkali metal source comprises one selected from

the group consisting of calcium hydroxide, calcium oxide, dolomitic lime, calcium chloride, calcium sulfate, and calcium carbonate.

9. The method of claim 1 wherein upon addition of the alkali metal source, an exothermic reaction produces a substantially solid product.

10. The method of claim 9 wherein said product comprises density higher than the

density of water.

1 1. The method of claim 1 wherein no glycol layer is visible in said generally

homogenous mixture.

12. The method of claim 9 wherein said exothermic reaction creates temperatures of up to about 200°C.

13. The method of claim 9 wherein said exothermic reaction is controlled to produce temperatures not exceeding about 150°C.

14. The method of claim 13 wherein said exothermic reaction is controlled by slow

addition of the alkali metal source.

15. The method of claim 13 wherein said exothermic reaction is controlled by cooling conditions.

16. The method of claim 2 wherein said unsaturated fat and said fat soluble acid are combined in a ratio between about 10:90 and about 90: 10.

17. The method of claim 2 wherein said unsaturated fat and said fat soluble acid are combined in a ratio between about 40:60 and about 60:40.

18. The method of claim 17 wherein said alkali metal source is added over a period of time of up to about 15 minutes.

19. The method of claim 17 wherein said alkali metal source is added to equal between about 25 and about 75 weight percent of the feedstuff produced.

20. The method of claim 1 wherein said one or more unsaturated fats each comprise less than about 15% fatty acids, said carboxylic acid is selected from the group consisting of propionic acid, bubyric acid, valeric acid, iso-butryic acid, and iso-valesic acid, and said alkali metal in said alkali metal source comprises one selected from the group consisting of calcium, magnesium and barium.

21. The method of claim 20 wherein said alkali metal source comprises one selected _ from the group consisting of calcium hydroxide, calcium oxide, dolomitic lime, calcium chloride, calcium sulfate, and calcium carbonate.

22. The method of claim 1 wherein said one or more unsaturated fats each comprise less than about 15% fatty acids, said carboxylic acid comprises propionic acid, and said alkali metal source comprises calcium hydroxide.

23. A method to produce a high energy feedstuff for animals comprising a first step of combining one or more unsaturated fats and a fat-soluble acid comprising a carboxyl group to form a generally homogenous mixture, and a second step of adding to said mixture an alkali metal source capable of reacting with said carboxyl group to form a salt wherein said second step produces an exothermic reaction and results in a substantially solid feed additive.

24. The method of claim 23 wherein said exothermic reaction produces adequate heat to dissipate moisture and produce a friable animal feed additive.

25. The method of claim 23 wherein said feed additive comprises a density higher than the density of water.

26. The method of claim 23 wherein said feed additive comprises a top dress product.

27. The method of claim 23 wherein said feed additive comprises a premix to be added to animal feed.

28. The method of claim 23 wherein said method produces a rumen-inert feedstuff.

29. The method of claim 23 wherein said first step combines said one or more

unsaturated fats and said fat-soluble acid in a ratio between 10:90 and 90: 10, said ratio selected in accordance with the nutritional needs of the animals to be fed the feed additive.