WO1994015482A1

WO1994015482A1 - Optimizing protein utilization with amino acid chelates

Info

Publication number: WO1994015482A1
Application number: PCT/US1993/010277
Authority: WO
Inventors: H. Dewayne Ashmead
Original assignee: Albion International, Inc.
Priority date: 1992-12-31
Filing date: 1993-10-27
Publication date: 1994-07-21
Also published as: MX9307737A

Abstract

A method for optimizing the digestion of dietary proteins into amino acids in warm-blooded animals is attained through the administration of mineral amino acid chelates. The primary minerals utilized are zinc, iron and manganese. Copper and cobalt are secondary optional minerals with copper being preferred. Magnesium and potassium are also optionally administered. The minerals consisting of iron, zinc, manganese, copper, cobalt and magnesium are provided in the form of amino acid chelates having a ligand to mineral molar ratio of at least 1:1, a molecular weight of no more than 1500 daltons and a stability constant of between about 106 and 10 16 and administered orally. Potassium may be added as an inorganic salt or as a 1:1 ligand to potassium amino acid complex. The minerals are utilized to improve the digestion of dietary protein to the amino acid or dipeptide stage where they are utilized to build body protein or used in enzymes or other body processes. The method is useful for optimizing the digestion of limited amounts of protein in the diet or in improving the assimilation of digested protein in situation of protein malabsorption.

Description

OPTIMIZING PROTEIN UTILIZATION WITH AMINO ACID CHELATES

BACKGROUND OF THE INVENTION

This invention relates to a method of optimizing dietary protein utilization in warm-blooded animals, including humans, by the administration of certain mineral amino acid chelates. More particularly, this invention relates to detecting the need for improved protein utilization and increasing the energy derived from the metabolism of amino acids and proteins in warm-blooded animals, including humans, through the use of certain amino acid chelates. Also, this invention is drawn to a method of determining the optimum ratio of amino acid chelates to protein in the diet to maximize the amount of small peptides or amino acids absorbed across the intestinal wall into the bloodstream or lymphatic system.

Protein is synthesized from basic units called amino acids. The protein in food must generally be digested into the amino acid or small peptide state before it can be absorbed from the small intestine into the body via the portal vein. Catabolism, or the breakdown of protein into amino acids, starts in the stomach and is concluded in the small intestine.

Acids and enzymes are required for catabolism to occur. These various steps are summarized in Table I.

Nutritionally, protein is in a constant state of demand. As the amino acids and small proteins from dietary protein are absorbed from the small intestine into the portal vein, they are translocated to various

areas of the body where they are synthesized into new body protein for growth and maintenance of body tissue or used for energy and regulation of body processes. At the same time, old body protein is degraded and excreted or used as stated above. This turnover of body protein varies in different parts of the body and with the quality and quantity of the dietary protein. In some animals, including human beings, these

processes of digestion and absorption of protein are inefficient or dietary protein intake is insufficient and therefore a method of achieving maximum dietary protein utilization would be of great value in

managing the diet in these cases.

In protein deficient animals where food digestion is not very efficient or where protein intake is insufficient, the body must make use of digestive secretions and desquamated cells from the lining of the intestine to meet its total need for amino acids. If dietary needs are not met the body will commence to digest itself which can be seen as weight loss or poor weight gains. A shortage of even a single essential amino acid will limit the use of all of the others and therefore reduce the efficiency of the entire feed ration. Because of this limiting effect of one amino acid to another, and because protein rich diets are generally more expensive than those low in protein, it makes good economic and physiological sense to

optimize the digestion of whatever dietary protein is available and increase the metabolic utilization of the amino acids which that protein contains.

In formulating feeds or diets for warm-blooded animals including human beings, five of the six basic nutrients are generally taken into account. These are carbohydrates, proteins, fats, vitamins and minerals; the sixth nutrient being water. The percentage of each nutrient digested in the food is called its

"digestion coefficient." Average digestion coefficients for many foods or ingredients of foods are provided in data tables as a result of numerous balance studies.

Balance studies are done by first analyzing the food for the percentage of protein that it contains. After a preliminary period of several days to allow the residue of any former food to be eliminated, a certain quantity of experimental food with a known protein composition is fed daily to the protein deficient animal or animals. The feces are collected, weighed and analyzed. A measured amount of amino acid chelates selected from the group consisting of zinc, manganese, iron and, optionally, copper and cobalt are then added to the food over a period of days. The feces are then collected and analyzed for undigested protein. This process is repeated until the minimum amount of undigested dietary protein is found in the feces. At this point the optimum ratio of amino acid chelates to dietary protein is ascertained.

Any improvement which can be made in the

efficiency of digestion of the proteins is a real economic and nutritional importance.

The role of proteins in the diet of animals or men is to provide, upon digestion, a source of amino acid building blocks for the synthesis of muscle, enzymes, connective tissue, and other substances that the body manufacturers from amino acids. If

sufficient carbohydrates or fats are absent from the diet of the animals and men, amino acids and proteins are used by the body for energy sources. A certain amount of ingested proteins remain undigested and are collected in the feces. If digestion is inefficient, potential dietary protein will be lost in the

digestion process. This makes inefficient digestion of protein result in greater expense because more protein must be consumed to meet the body's

requirements for dietary protein. Furthermore, with growing animals or children it is not profitable to have the body catabolize the muscle protein for energy needs. Thus it would be beneficial both economically and to the recipient host to improve the digestion coefficient of dietary proteins by improving their digestibility.

OBJECTS AND BRIEF SUMMARY OF THE INVENTION

It is therefore an object of the present

invention to provide a method of optimizing the utilization of dietary protein in warm blooded animals by the administration of an appropriate selection of amino acid chelates.

It is also an object of this invention is to provide a method of determining the optimum ratio of amino acid chelates to dietary protein for maximum efficiency in the absorption and utilization of dietary protein.

A still further object of the invention is to provide a method for facilitating digestion of

proteins into amino acids by maintaining and enhancing the natural enzymatic activity of the animal through the administration of appropriate chelates that increase the absorption of dietary protein by the body.

Another object of the invention is to provide a means of determining the optimum ratio of amino acid chelates to protein in the feed of animals that have protein deficiencies to enable the animal to more efficiently utilize the protein in such feed.

These and other objects may be realized by providing an appropriate formulation containing primary minerals iron, zinc and manganese in the form of amino acid chelates with optional amounts of secondary minerals selected from the group consisting of copper and cobalt which are also in chelated form. Additional digestive efficiency of proteins may, in some circumstances, be obtained by also adding one or more other mineral supplements selected from the group consisting of magnesium, as an amino acid chelated and potassium which may be provided in the form of an amino acid complex or chloride salt or mixture or both.

By appropriate formulation is meant the providing of at least one member selected from the group

consisting of iron, zinc, manganese and, if used, copper, cobalt, magnesium and potassium in a form which is bioavailable to the animal at the proper intestinal mucosal cell utilization site. Also, the ratio of one mineral to another may be significant and may vary depending upon the species of animal, and the degree to which the digestion coefficient needs to be improved.

The chelates of iron, manganese, zinc, copper, cobalt and magnesium and complexes of potassium are prepared by chelating or complexing the mineral with an amino acid or peptide ligand wherein the ligand to mineral ratio is at least 1:1 and, except for

potassium, is preferably 2:1 or higher and wherein the molecular weight of the amino acid chelate formed is not greater than 1500 Daltons and preferably does not exceed 1000 daltons. Such amino acid chelates are stable and are generally taught in the prior art to be absorbed intact through the intestinal tract via an active dipeptide transport system. Such amino acid chelates have a stability constant of between about 10⁶ and 10¹⁶. A more detailed description of such chelates and the method by which they are absorbed through the intestine is documented in Ashmead et al., U.S. Patent 4,863,898 which issued September 5, 1989 and also in Ashmead et al., Intestinal Absorption of Metal Ions and Chelates, Published by Charles C. Thomas,

Springfield, Illinois, 1985. This invention, however, is not directed to metal uptake into tissues or metal transport across the intestine for absorption in the blood. Therefore, although amino acid chelates and some of the uses to which they are applicable are documented in the art, there is no method set forth that teaches how to optimize the amount of amino acid chelates in the feed mixture to provide maximum digestive efficiency of dietary protein.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a method for optimizing the utilization of dietary protein in a warm blooded animal by means of the administration of effective amounts of selected amino acid chelates. Initially, the need for utilizing the present invention is determined by some symptoms indicating that the animal is inefficiently or under utilizing the protein being consumed, i.e. protein malabsorption. One practical way of determining malabsorption of proteins, peptides and amino acids is by detecting the presence of excessive undigested protein or peptides in the feces of the animal. However, other symptoms of protein deficiency may be used as a signal, i.e. insufficient protein in the diet, retarded growth, protein

catabolism, protein-calorie malnutrition (PCM) and the like.

Normally, the presence of protein malabsorption or the improvement or lessening of protein

malabsorption may be determined by standardizing the protein content in the food of the animal and by making repeated analysis of the feces for the presence of undigested protein over a period of time. For example, even an animal which on the surface may appear to be utilizing protein satisfactorily may be suffering the effects of protein malabsorption. Such a condition may be determined by comparing the protein content of the feces of such an animal against a

"standard" obtained by repeated analysis for undigested protein from a standardized protein diet fed to that animal species. The early detection of protein malabsorption may prevent future problems relative to the growth, development and overall health of the animal.

Once the presence of protein malabsorption is determined, it may be alleviated or corrected by the administration of appropriate amounts of mineral amino acid chelates wherein the minerals are primarily selected from the group consisting of zinc, manganese and iron with or without optional amounts of copper and cobalt. Iron, zinc, manganese and cobalt are minerals which are active parts of enzymes or are incorporated into amidase enzymes such as the various peptidases shown in Table 1. Copper plays a

supporting role in optimizing the activity of

proteolytic enzymes and cobalt is a cofactor in many enzyme systems. Potassium and magnesium are also important minerals relative to protein digestion and utilization. Preferably, the compositions utilized in the present invention will combine zinc, iron and manganese although individual minerals or mixtures of two of these minerals may also be advantageously utilized. Iron, zinc and manganese combinations, with or without copper are preferred base mixture for providing enhanced protein utilization. Most

preferably copper will be added to the three minerals noted above. Cobalt is a cofactor in may enzyme systems and its incorporation may optimize the base mixture. However, both cobalt and copper are

secondary to the incorporation of iron, zinc and manganese. Potassium and magnesium may be optionally used but are also secondary to the utilization of iron, zinc and manganese and are, in fact, secondary to the use of copper and cobalt.

Preferably, the administration will be

accomplished by feeding the animal a food ration containing dietary proteins and at least one member selected from the group consisting of iron, zinc, manganese and, optionally, copper and/or cobalt in the form of amino acid chelates having a ligand to mineral mole ratio of at least 1:1, a molecular weight of no more than 1500 daltons and a stability constant of between about 10⁶ and 10¹⁶.

In the treatment of animals such as poultry, cattle, pigs and the like, the feces of the animal may be analyzed for the presence of undigested protein and the amount and/or ratio of amino acid chelates

adjusted until a satisfactory utilization of protein is attained. That may require repeating the steps of chelate administration and feces analysis over a period of time until the optimum ratio of chelate to dietary protein is obtained for the most efficient digestion of the dietary protein. The same procedure may be used for the treatment of humans. However, more subjective determinations relative to the health of humans may also serve as useful indicators of the need for improved protein utilization, .e.g. the lack of sufficient protein in the diet, symptoms of muscle catabolism and the like.

The absorption of hydrolyzed proteins as small peptides and/or amino acids from the intestine is influenced by the general overall health or condition of the animal. This not only includes the general health of that animal, but also its current nutrition. The protein deficient animal cannot assimilate dietary protein efficiently. It has generally been thought that mineral nutrition was effective only when the mineral had crossed the intestinal lining and entered into the bloodstream. The present invention shows that certain mineral chelates become effective in the absorption of amino acids and small peptides across the intestinal walls into the blood stream. Ashmead et al., U.S. Patent 4,020,158; Ashmead, U.S. Patent No. 4,076,803; Jensen U.S. Patent No.

4,167,564; Ashmead, U.S. Patent 4,774,089 and Ashmead, U.S. Patent 4,863,898 all teach various uses for amino acid chelates in reference to increasing absorption of essential minerals into biological tissues. Some of these patents suggest that certain mineral and ligand combinations can enhance metal uptake in specific organs or tissues where specific biological functions are enhanced, i.e. minerals crossing the placental membranes into foeti, estrus or spermatogenesis, etc. However, it has not heretofore been known that protein digestion and amino acid or dipeptide absorption across the intestinal wall be enhanced by the use of metal chelates of amino acids.

As noted above, the amino acid chelates or complexes utilized have a ligand to mineral ratio of at least 1:1 and preferably 2:1 or greater, a

molecular weight of no more than 1500 daltons and preferably not more than 1000 daltons and a stability constant of between about 10⁶ and 10¹⁶. In the field of animal nutrition, the American Association of Feed Control Officials has issued the following official definition: "amino acid chelate - a metal ion from a soluble salt with amino acids with a mole ratio of one mole of metal to one to three (preferably two) moles of amino acids to form coordinate covalent bonds. The average weight of the hydrolyzed amino acids must be approximately 150 and the resulting molecular weight of the chelate must not exceed 800." It is also documented that amino acid chelates can be prepared from metal ions which do not come from soluble salts. Ashmead, U.S. Patent 4,599,152 and Ashmead, U.S.

Patent 4,830,716 both disclose methods of preparing pure amino acid chelates using metal sources other than soluble metal salts. However, it is not critical to the present invention which manner the amino chelates are made provided they meet the criteria stated above.

The amino acid compositions will preferably be administered to the warm-blooded animal orally. In many cases mixtures of the chelates in the food, drinking water or other ration forms given to the animal may be used. For example, the chelates may be mixed with salt (sodium chloride) when being

administered to the bovine species. They may

similarly be mixed with feed or rations destined for general animal or livestock usage. In the case of humans, the chelates may be administered in the form of tablets, capsules, powders, syrups, elixirs or any other suitable form. They may be mixed with fillers, excipients, vitamins and other foodstuffs.

The exact amount of mineral to be administered, and the ratio of one mineral to another, will depend upon the analysis of the fecal protein as the various combinations of chelated amino acids are added to the diet. To make a determination, the correct

interpretation of data may be more important than the actual numbers generated in an assay, and values must be correlated to bioavailability and antagonistic parameters of one trace element to another or from one trace element to other minerals such as copper and iron. An assay of the diet may also be important to determine mineral amounts in the diet as well as carbohydrate, protein and fat content and identify deficiencies and/or antagonistic factors which may affect trace minerals when administered.

Therefore, the exact amount of amino acid

chelate, which minerals to use and in what ratios, are preferably determined on an empirical basis according to need. Hence, the term, "effective amount" of one or more minerals is based on both the amount of mineral and the ratio of one mineral to another which has been determined to be required to meet the needs of a particular warm-blooded animal or group of animals, including humans, to enhance the protein digestion coefficient. Based on collected data over periods of time, it will be possible to pre-formulate compositions based on known needs of the animal species ingesting particular types or forms of proteins. However, one skilled in the art, based on the information provided herein, can determine without undue experimentation what an "effective amount" of a composition is and how to administer it accordingly. It is not possible to categorically state that "x" mg of trace mineral per kg of animal body weight is what is needed to optimize protein digestion. Nor is it possible to state, for example, that the ratio of Fe to Cu or Zn will be "a:b" in all instances. Each different food ration may require different amounts of minerals and/or ratios of minerals to maximize protein absorption.

Using iron as a standard indicator, the optimal molar ratios of iron to copper, zinc and manganese are between about one mole iron to 0.1 to 0.5 moles each of copper, zinc and manganese. The mole ratios of copper, zinc and manganese to each other may vary from about 5:1 to 1:5. When utilized, the molar ratio of iron to cobalt will be between about 1:0.003 and

1:0.015. Just what role each of these minerals plays in protein utilization isn't known. As noted above, it is also seen that digestive efficiency of dietary protein may be improved through the use of adding magnesium also in the from of an amino acid chelate, to complement one or more minerals selected from the group consisting of iron, zinc, manganese and,

optionally, copper and cobalt. When present, the molar ratio of iron to magnesium will be between about one mole iron to 30 to 70 moles of magnesium, with at least some or all of which may be present as an amino acid chelate. Finally, potassium in the form of an amino acid complex or inorganic salt, such as

chloride, or mixture or both may be combined with the above chelated minerals. When used, the potassium is preferably present in mole ratios, relative to iron, of between about 1:1 to 1:10 iron to potassium with ratios of about 1:5 being preferred.

The amino acid chelates are preferably present in ligand to metal ratios of at least 1:1. That is the maximum ligand to potassium ratio. However, divalent and metals having higher valencies and or coordination bonding site can accommodate ligand to metal ratios of 2:1 or even up to 4:1. However, for purposes of assimilation across the mucous cell membrane it appears that ratios of 2:1 to 4:1 are optimal. At higher ratios the molecular weight of the chelate becomes too high for assimilation.

A series of tests were conducted in which amino acid chelates were mixed at different rates in

commercial feeds provided to animals, and the

metabolic efficiency of those feeds as it relates to increase protein digestion and amino acid metabolism ascertained. The tests were conducted on chickens (broilers and layers), pigs and cattle.

The following examples are illustrative of the invention.

EXAMPLE 1

In the case of the broilers, 180 male birds were divided into six groups of 30 each. Three different diets were studied: (1) corn (6.9% digestible protein), soybean (36.9% digestible protein), and barley (9.2% digestible protein). Feeds with

different percentages of digestible protein

availability were provided to ascertain if they would be affected by the inclusion of the amino acid

chelates. Each diet had a control group of 30 birds and an experimental group of 30 birds. Each experimental group was further subdivided into three groups of ten birds each. Each experimental subgroup had the formula of amino acid chelates shown in Table 2 included with the feed at the rate of 50, 100 or 200 ppm. The experiment was designed as shown in Table 3.

All of the birds were housed in wire cages and consumed both water and feed ad libitum. Prior to receiving the supplements each experimental and control group received the same feed for a period of ten days (i.e., corn-control/experimental,

soybean-control/experimental, and barley- control/experimental).

All of the feeds contained Cr₂O₃ which was used as both an indicator of the digestibility of the feed and to measure the amino acid content of the feces. The latter was measured by a Beckman automatic analyzer using acid-insoluble ashes and the Cr₂O₃ as markers. Energy determinations were accomplished with a

calorimetric bomb. All of the broilers were sacrificed on the 60th day of the treatment period and the intestinal content of the ileocecal tract removed. Feces were collected in this manner to avoid contamination with the urine which would have added uric acid and urates to the feces and changed the analytical results.

Feed samples were also assayed to ascertain the total energy and amino acids potentially available to the birds. The mean results obtained from

calculations of linear regressions are summarized in Table 4. The data is expressed as percent variations of the experimental groups compared to the controls. The percentage increases or decreases of metabolizable energy from the amino acids and the digestibility of the amino acids in the feeds are preceded. By a plus (+) for an increase and a minus (-) for a decrease as compared to the controls. An asterisk (*) indicates that the value is statistically significant at the P<.05 level. Table 4

Increased Metabolizable Energy and Available Amino Acids from Broiler Feeds in Broilers Receiving Amino Acid Chelates

As the data in Table 4 demonstrates, in every instance regardless of the amount of digestible protein in the feed, the presence of the amino acid chelates in the feeds increased the metabolizable energy and the available amino acids over the same feeds without the chelates. The increases in

utilizable energy were all statistically significant. There were significant increases in 58% of the amino acids measured.

EXAMPLE 2

In a second experiment 180 laying hens were used. The experimental design was identical to the design for that of the broiler experiment except the amino acid chelates fed to the three experimental sub-groups in each experimental group were increased to 75, 150 and 225 ppm of the amino acid chelate formula in Table 2 in the feed. The pre-supplementation conditioning period was ten days. The treatment period lasted 50 days. All hens were sacrificed on the 51st day and their feces and feed assayed as described above.

Table 5 summarizes the, mean linear regressions which are expressed as percent variations of the

experimental groups compared to the control groups. Data marked with an asterisk is statistically

significant at the P<.015 level.

Table 5

Increased Metabolizable Energy and Available Amino Acids from Layer Feeds in Layers Fed Amino Acid Chelates

The data in Table 5 demonstrates that when amino acid chelates are included as part of the laying hens' feed, the birds are able to obtain additional energy from the feed. The presence of the chelates in the feed also make the amino acids that are normally in the feed more available to the chickens. Sixty-seven percent of the time, the increase in amino acid availability was significant.

It should be noted that the layers were older birds than the broilers and therefore the increases seen in Table 5 are generally not as great as the increases noted in Table 4. The age factor will be addressed in greater detail later.

EXAMPLE 3

Having determined that the amino acid chelates improved the protein nutritional value of feeds given to chickens, a similar study was made using pigs. Two-test Periods were studied. The first period used male, non-castrated pigs that were four weeks old and had just been weaned, and followed them for 30 days. The second period started with feeder male non-castrated pigs that each had a beginning weight of approximately 70 Kg and were seven weeks old. These were also followed for 30 days.

Thirty-six pigs which had been raised in

confinement were used in each study. They were divided into two groups: experimental and control. The experimental groups were further subdivided into three groups of six pigs each. These subgroups were fed 50, 100 or 200 ppm of amino acid chelates (Table 2) in their feed. Other than the inclusion of the amino acid chelates in the feeds of the experimental groups, the pigs received the same feed ad libitum. The feed formulation given to the pigs is shown in Table 6.

On the last day of each test period the feces of each pig were collected for a 24 hour period. These samples were measured by calorimetric bomb for the energy remaining in them and by a Beckman automatic analyzer for the undigested protein. This data was compared to assays of the feed samples to ascertain the degrees of digestibility of the feeds with and without the presence of the amino acid chelates.

Table 7 presents the summarized mean results which were obtained from linear regression calculations. The data is expressed as plus (+) or minus (-) percent variations of the experimental groups compared to the controls.

Percentages followed by an asterisk (*) are

statistically significant at the P<.05 level.

Table 7

Increased Metabolizable Energy and Available Amino

Acids from Swine Feeds

The data in Table 7 demonstrates that when the amino acid chelates are included as part of the feed, there is greater digestion and utilization of both the available energy and the naturally occurring amino acids in the feed. Seventy-three percent of the amino acids measured increased significantly in the older pigs. This enhanced utilization appears to be a function of the age of the pigs. As they become older, the availability of the energy and amino acids tends to diminish somewhat. EXAMPLE 4

Because the observation that the availability of the energy and amino acids tends to diminish somewhat at pigs become older, and because protein malnutrition in humans also most severely affects the young

(Kwashiorkor disease, etc.) it was decided to further test this concept in growing pigs.

A group of crossbred Durlock and Hampshire pigs were divided into three groups: (1) a confined treated group, (2) a confined control group, and (3) a pasture control. All of the pigs in the study had just been weaned and were assessed until market time. The pasture group grazed free choice. The two confined groups received the same commercial swine feed except that the treated group received an amino acid chelated ("AA Chelate") or complexed ("AA Complex") mineral supplement as shown in Table 8. The feed given to the confined control group contained the same minerals and in the same quantities as seen in Table 8, except that the minerals were provided as inorganic mineral salts.

The commercial feed formula used in this study is shown in Table 9.

The results of this test in which the pigs were followed from weaning to market (100 Kg) are

summarized in Table 10.

While not all of the data was positive, the indications were that the amino acid chelates enhanced protein metabolism. This was particularly noted in the average daily gain of the pigs since the protein is used for growth. Their feed conversion, which is basically a reflection of protein metabolism, was 17.1% better than the pasture group and 6.3% better than the confined group (which received exactly the same feed less the amino acid chelates).

The above results were confirmed in another test utilizing 183 SPF Feeder pigs divided into two groups. There were 30 pigs in the control group and 153 in the treated group. In all cases the average feed consumed per pound of weight gain was less in the amino acid treated group than in the control.

The protein sparing effects resulting from administration of the amino acid chelates is evident. It is believed that the equivalent growth rates of the pigs fed less protein compared to those fed higher protein levels is due to the minerals in the chelates causing greater activity in the multitude of enzymes related to protein utilization that require these minerals. The greater bio-availability of minerals in amino acid chelated form allowed more of the minerals to activate the proteinase enzymes as well and those enzymes, such as magnesium, that are involved in anabolism. Thus, the optimal mineral source is in the form of amino acid chelates.

EXAMPLE 5

This same trend of reduced utilization of

nutrients as a function of age also appeared in growing calves. In this series of experiments two groups of calves were used. The first group

consisted of 36 bull Piedmont breed calves that were 15 days old at the beginning of the study. They were divided into two groups of 18 calves each,

experimental and control. The experimental group received the amino acid chelate blend shown in Table 8 at the rates of 150, 200, or 250 ppm of supplement per mixed in the reconstituted milk formula shown in Table 11.

In addition to milk, the calves were given corn, wheat, and hay as they matured enough to consume them. The experiment lasted ninety days including a ten-day stabilization period at the beginning of the

experiment during which time no amino acid chelates were fed.

The second group of calves consisted of forty bulls of the same breed as above. They were ten weeks old at the commencement of the study which continued for eighty days including a ten day stabilization period during which time no amino acid chelates were fed.

The calves in this second group were divided into two sub-groups: experimental (30 calves) and control (10 calves). The experimental group was subdivided further into three groups of ten animals each and fed the amino acid chelate supplement shown in Table 2 at the rates of 100 ppm, 150 ppm or 200 ppm depending on the group. The chelates were blended in the dry feed. The formulation for that feed is shown in Table 12. This feed formula was blended so that in every 102 Kg of feed there was 40 Kg of corn silage, 40 Kg of alfalfa hay, 20 Kg of barley, and 2 Kg of the vitamin pack.

On the last day of the eighty days of the test period, a 24 hour sample of feces was taken from every calf and assayed for the energy and the amino acids still remaining with the techniques described above. The results were compared with feed analyses.

A summary of the mean results after linear regression calculations for the two groups of calves are presented in Table 13. The differences between the experimental groups and controls are indicated by plus (+) or minus (-). Data that is statistically significant at the P<.05 level is indicated by an asterisk (*).

As seen in Table 13, when the amino acid chelates are included in the bovine feeds, amino acid

availability is improved. As in the above examples utilizing pigs and chickens, the older animals are not as efficient as the younger ones. The differences in the two groups of calves may be due to two digestive models. The younger calves are monogastric, whereas in the older calves, the rumen has developed, and they have become polygastric. There may also be

differences based on protein requirements as a

function of age. Very young animals grow at a much more rapid rate than do older animals and consequently require a larger amount of amino acids from their dietary protein in order to support this rapid growth.

Rumen material was removed from all of the older calves and analytically compared. An increase in the amount of propionic acid with corresponding decreases in the amounts of methane and ammonia was found in the experimental groups. The increase of propionic acid and decrease of methane result in greater obtainable energy from the ration. The decrease in ammonia production results in a protein sparing effect which produces greater utilization of the amino acids in the feed to support increased growth. EXAMPLE 6

The above examples illustrate the effects of the amino acid chelate utilization in improving

digestibility of animal feeds. It is believed that this is due to increased bioavailability of these chelates to the mineral dependant digestive enzymes which are produced at the mucosal cell level. This examples was designed to demonstrate whether there was an increased utilization of the amino acids at the cellular level.

Eight male Westar-Hagemann white rats weighing approximately 100 g each were used in this study. All were fed the same commercial rat chow for ten days to stabilize them. They were then divided into four groups of two rats each. One group was the control. The remaining groups, labelled experimental, received 50, 100 or 150 ppm of the amino acid chelates shown in Table 8 mixed with their feed. These chelates were fed to the three experimental groups for ten days. The control group received the same feed as the experimental groups minus the amino acid chelates for the same ten day period. All feed and water was provided ad libitum.

At the end of ten days all of the rats were sacrificed by cervical dislocation. Their duodenums and livers were removed. The duodenums were cut longitudinally and washed with distilled water. The mucus membrane was then scraped off and put in

containers which each contained 4 ml of

deionized/distilled water. One microcurie of ¹⁴C (1 microcurie equals 0.1 ml) was added to the membrane- water mixture and homogenized it for 20 minutes. It was then refrigerated at 0°C during the incubation period. The livers of the rats were treated in a similar fashion. They were homogenized for 20 minutes after ¹⁴C was added. They were then incubated .

Protein synthesis was measured by incorporating the ¹⁴C into the amino acids in the tissues. The labelled amino acids were then determined by

scintillation counting. The data, which is expressed as corrected counts per minute is shown in Table 14.

The data in Table 14 demonstrates that protein synthesis in the liver increased over the control

20.7% (at 50 ppm), 25.8% (at 100 ppm), or 35.7% (at

150 ppm) depending on the quantity of amino acid chelates included in the feed. Protein synthesis in the duodenum increased over the control 19.7% (at 50 ppm), 45.8% (at 100 ppm) or 54.9% (at 150 ppm)

according to the amount of amino acid chelate

supplemented. From these tests, it appears that there is more protein synthesis from the same quantity of dietary protein where there is a greater concentration of the amino acid chelates in the diet. The synthesis starts in the intestinal tissue and continues in other organs and tissues. The synthesis is directly

dependent upon the quantity of amino acids absorbed from the dietary protein. When the amino acid

chelates are added to the diet, the digestion of dietary protein is more efficient. More protein is digested to the amino acid state and consequently absorbed, where it can be synthesized into new protein in the various tissues and organs of the body after absorption as seen in Tables 10 and 14.

The studies illustrated by the above examples confirm the value of administering amino acid chelated mineral supplements to animals and birds. The data demonstrates that when the amino acid chelates are included, the animal or bird is able to extract more energy and amino acids from the feed. Furthermore, this increased amino acid availability results in increased availability of supplemental and natural amino acids in the feed and their subsequent

incorporation into the tissues of the animals. The result is greater protein synthesis within the body and support for body growth and development.

While the above provides a detailed description of the invention and the best mode presently known of practicing it to the extent that it has been

developed, the invention is not to be limited solely to the description and examples. There are

modifications which may become apparent to one skilled in the art in view of the description contained herein. Therefore, the invention is to be limited in scope only by the following claims and their

functional equivalents.

Claims

1. A method for optimizing digestion of dietary proteins into amino acids in warm-blooded animals having a need for improved dietary protein utilization which comprises the steps of :

(1) determining the need for improvement in dietary protein utilization in said animal;

(2) providing a composition containing an effective amount of the primary minerals zinc, iron and manganese, each primary mineral being in the form of an amino acid chelate having a ligand to mineral mole ratio of at least 1:1, a

molecular weight of no more than 1500 daltons and a stability constant of between about 10⁶ and 10¹⁶ as needed optimize the digestion of dietary protein into amino acids in said animal, and

(3) orally administering an effective amount of said composition to said warm-blooded animal for a period of time sufficient to optimize the utilization of dietary protein in said animal.

2. A method according to Claim 1 wherein said ligand to primary mineral mole ratio is 2:1 or

greater.

3. A method according to Claim 2 wherein said primary mineral chelates have a molecular weight no greater than about 1000 daltons.

4. A method according to Claim 3 wherein composition contains at least one other secondary mineral selected from the group consisting of copper and cobalt said secondary mineral being in the form of an amino acid chelate having a ligand to mineral mole ratio of at least 1:1, a molecular weight of no more than 1500 daltons and a stability constant of between about 10⁶ and 10¹⁶.

5. A method according to Claim 4 wherein said ligand to secondary mineral mole ratio is 2:1 or greater.

6. A method according to Claim 5 wherein said secondary mineral chelates have a molecular weight no greater than about 1000 daltons.

7. A method according to Claim 6 wherein copper is present as a secondary mineral chelate.

8. A method according to Claim 7 wherein the molar ratios of iron to zinc, manganese and copper are between about one mole iron to 0.1 to 0.5 moles each of zinc, manganese or copper.

9. A method according to Claim 8 wherein the mole ratios of zinc, manganese and copper to each other may vary from about 5:1 to 1:5.

10. A method according to Claim 9 wherein cobalt is also present as a secondary mineral chelate.

11. A method according to Claim 10 wherein the molar ratio of iron to cobalt is between about 1:0.003 and 1:0.015.

12. A method according to Claim 9 wherein said composition additionally contains one or more minerals selected from the group consisting of magnesium and potassium said minerals also being in the form of an amino acid chelate or complex having a ligand to mineral mole ratio of at least 1:1, a molecular weight of no more than 1500 daltons and a stability constant of between about 10⁶ and 10¹⁶.

13. A method according to Claim 9 wherein said composition is administered in the food of said animal.

14. A method according to Claim 13 wherein said composition is continuously available to said animal.

15. A method according to Claim 9 wherein said determining the need for improvement in dietary protein utilization in said animal is done by

determining the digestion coefficient for protein in said animal and comparing said coefficient with standardized digestion coefficients.

16. A method according to Claim 9 wherein said determining the need for improvement in dietary protein utilization in said animal is done by (a) first analyzing the food ration of said animal for the percentage of protein that it contains, (b) feeding said food ration to said animal for a determined period of time and collecting and analyzing feces from said animal to determine the presence of undigested protein, (c) administering to said animal a

predetermined amount of said composition, (d)

continuing steps (b) and (c) while adjusting the minerals in said composition until the feces analysis shows the utilization of optimal amounts of protein.

17. A method according to Claim 9 wherein determining the need for improvement in dietary protein utilization in said animal is indicated by the presence of insufficient protein in the diet of said animal.

18. A method according to Claim 9 wherein determining the need for improvement in dietary protein utilization in said animal is indicated by the presence of retarded growth.

19. A method according to Claim 9 wherein determining the need for improvement in dietary protein utilization in said animal is indicated by the presence of protein catabolism, protein-calorie malnutrition (PCM).

20. A method according to Claim 9 wherein determining the need for improvement in dietary protein utilization in said animal is indicated by the presence of protein-calorie malnutrition (PCM).