Use of a metal supplement in animal feed

Abstract

The invention pertains to the use of a supplement for making metals (nutritionally) available to animals, said supplement comprising at least one compound selected from the group consisting of glutamic acid N,N-diacetic acid (GLDA), a metal complex of GLDA, a sodium salt of GLDA, a potassium salt of GLDA, methylglycine-N,N-diacetic acid (MGDA), a metal complex of MGDA, a sodium salt of MGDA, a potassium salt of MGDA, ethylenediamine N,N′-disuccinic acid (EDDS), a metal complex of EDDS, a sodium salt of EDDS, a potassium salt of EDDS, iminodisuccinic acid (IDS), a metal complex of IDS, a sodium salt of IDS, and a potassium salt of IDS.

Claims

1. A method of making a metal nutritionally available to an animal comprising the step of providing the animal with a supplement incorporated in animal feed, animal drinking water, salt licks, or premixes therefor, wherein the supplement comprises at least one compound selected from the group consisting of glutamic acid N,N-diacetic acid (GLDA), a metal complex of GLDA, a sodium salt of GLDA, a potassium salt of GLDA, methylglycine-N,N-diacetic acid (MGDA), a metal complex of MGDA, a sodium salt of MGDA, and a potassium salt of MGDA.

2. The method according to claim 1 wherein the supplement comprises at least one anion selected from the group of anions of GLDA, or MGDA and at least one cation selected from the group consisting of calcium, magnesium, copper, zinc, iron, manganese, chromium, and cobalt cations.

3. The method according to claim 1, wherein the metal is selected from the group consisting of zinc, copper, iron, manganese, cobalt, chromium, calcium, and magnesium.

4. The method according to claim 1 wherein the supplement comprises a metal complex of GLDA or a metal complex of MGDA.

5. The method according to claim 4 wherein the supplement comprises a zinc, manganese, iron or copper complex of GLDA.

6. The method according to claim 1 wherein the supplement is incorporated in animal feed and the animal feed further comprises a feedstuff from the group of legumes, forages, grain, leaves, or derivatives thereof.

7. The method according to claim 1 wherein the animals are domestic animals or aquatic animals selected from the group consisting of chickens, layers, turkeys, swine, cattle, sheep, goats, horses, cats, dogs, fish, or shrimp.

8. The method according to claim 1 wherein the supplement further comprises at least one compound selected from the group consisting of proteins, fats, carbohydrates, minerals, vitamins, vitamin precursors, and water or other edible liquids.

9. The method according to claim 1 wherein the supplement is chosen from a zinc or copper complex of GLDA.

10. The method according to claim 1 comprising (i) one or more compounds selected from the group consisting of a sodium salt of GLDA, a potassium salt of GLDA, a sodium salt of MGDA, a potassium salt of MGDA, a calcium complex of GLDA, a magnesium complex of GLDA, a calcium complex of MGDA, and a magnesium complex of MGDA; and (ii) one or more salts selected from the group consisting of a copper salt, a zinc salt, an iron salt, a manganese salt, a chromium salt, and a cobalt salt.

11. The method of claim 1 wherein the supplement comprises a metal complex of glutamic acid N,N-diacetic acid (GLDA) or methylglycine-N,N-diacetic acid (MGDA) wherein the metal is selected from the group consisting of copper, manganese, chromium, cobalt, magnesium, and calcium.

12. The method of claim 11 wherein the complex is Na.sub.2Cu-GLDA, K.sub.2Cu-GLDA, H.sub.2Cu-GLDA, NaKCu-GLDA, NaHCu-GLDA, KHCu-GLDA, Cu.sub.2-GLDA, Na.sub.2Zn-GLDA, K.sub.2Zn-GLDA, H.sub.2Zn-GLDA, NaKZn-GLDA, NaHZn-GLDA, KHZn-GLDA, Zn.sub.2-GLDA, Na.sub.2Mn-GLDA, K.sub.2Mn-GLDA, H.sub.2Mn-GLDA, NaKMn-GLDA, NaHMn-GLDA, KHMn-GLDA, Mn.sub.2-GLDA, NaCu-MGDA, KCu-MGDA, HCu-MGDA, NaZn-MGDA, KZn-MGDA, HZn-MGDA, NaMn-MGDA, KMn-MGDA, or HMn-MGDA.

13. The method of claim 1 comprising a step of adding the supplement to animal feed, animal drinking water, salt licks or premixes, wherein the supplement comprises (i) a metal complex of glutamic acid N,N-diacetic acid (GLDA) or methylglycine-N,N-diacetic acid (MGDA), or (ii) at least one compound selected from the group consisting of GLDA, a sodium salt of GLDA, a potassium salt of GLDA, MGDA, a sodium salt of MGDA, a potassium salt of MGDA.

14. The method of claim 1, wherein the animal feed, animal drinking water, salt licks, or premixes therefor comprises the metal.

15. The method of claim 14, wherein the animal feed, animal drinking water, salt licks, or premixes therefor has a reduced amount of the metal compared to animal feed, animal drinking water, salt licks, or premixes therefor that does not have the supplement.

16. The method of claim 1, wherein the animal has a nutritional need for the metal.

17. The method of claim 1, wherein the animal is provided with an effective amount of the supplement to make the metal nutritionally available to the animal.

18. The method of claim 13 wherein one or more salts selected from the group consisting of a copper salt, a zinc salt, an iron salt, a manganese salt, a chromium salt, and a cobalt salt is added to the animal feed, animal drinking water, salt licks or premixes along with the supplement.

Description

EXAMPLES

(1) According to P. Wu et al. in International Journal of Food Science and Technology 2009, 44, 1671-1676, “phytic acid has a strong ability to form a complex with multivalent metal ions, especially zinc, calcium, and iron. This binding can result in very insoluble salts with poor bioavailability of the minerals.” C. I. Febles et al. in Journal of Cereal Science 36 (2002) 19-23, remark that “The acid groups present in phytic acid facilitate the formation of several salts, those of the alkaline metals being soluble in water, while divalent metal salts are almost insoluble.”

(2) In order to demonstrate the effect of the presence of phytic acid (ex Sigma-Aldrich) on the solubility of various zinc and copper salts, experiments as outlined below were conducted. At 2 different pH-values, i.e. at pH=4 and pH=6, in total 4 zinc and 3 copper salts were combined with a twofold molar excess of phytic acid. The following 3 concentrations of the final metal concentration were tested, i.e. high (H) at 25 mmol/kg, medium (M) at 5 mmol/kg, and low (L) at 0.5 mmol/kg.

(3) Preparation of the Test Solutions

(4) For each concentration and pH a separate phytic acid stock solution was prepared by diluting the calculated amount of phytic acid with de-mineralized water, setting the pH with diluted NH.sub.4OH solutions, and filling up with demineralized water up to the calculated amount. The following 4 phytic acid solutions were prepared in this way: 1. 0.125 mol/kg phytic acid at pH=4 2. 0.125 mol/kg phytic acid at pH=6 3. 0.050 mol/kg phytic acid at pH=4 4. 0.050 mol/kg phytic acid at pH=6

(5) Then the following 2 phytic acid solutions were prepared by diluting the 0.05 M ones. The pH values of these 2 solutions were not adjusted. 5. 0.005 mol/kg phytic acid at pH≈4 6. 0.005 mol/kg phytic acid at pH≈6

(6) The metal complexes and chelates were prepared by weighing an amount of either ZnSO.sub.4.H.sub.2O (35.7% Zn, ex Sigma-Aldrich) or CuSO.sub.4.5H.sub.2O (25.2% Cu, Baker Analyzed (supplier Mallinckrodt Baker B.V.)) and adding the corresponding amount of complexing or chelating agent. A small excess of 2% of the complexing or chelating agent intake was used to prepare the metal-containing solutions. This ensures a complete complexation or chelation of the metal ions. The mixture was dissolved in part of the demineralized water. The pH was adjusted in order to reach a pH value between approximately 4 and 5. All solutions were filled up with demineralized water to 400 g.

(7) The following 4 zinc-containing solutions were prepared in this way. ZnSO.sub.4 0.125 mol/kg, 9.158 g ZnSO.sub.4.1H.sub.2O were dissolved in de-mineralized water showing a pH of 5.63 and after 1 day some sediment was noticed. With 0.5 M H.sub.2SO.sub.4 the pH was reduced to 4.28, after which the solution became clear. Zn(Lysine).sub.2 0.125 mol/kg, 9.158 g ZnSO4.1H.sub.2O, and 0.255 mol/kg, 18.691 g Lysine (Fluka (supplier Sigma-Aldrich)) were dissolved in demineralized water. Within minutes a clear solution was obtained with a pH of 4.06. Zn(Methionine).sub.2 0.125 mol/kg, 9.158 g ZnSO4.1H.sub.2O, and 0.255 mol/kg, 15.220 g Methionine (Fluka (supplier Sigma-Aldrich) were dissolved in demineralized water. The pH was adjusted from pH 4.03 to pH 4.51 with NH.sub.4OH 2.5% to obtain a clear solution. Zn-GLDA-Na.sub.2 0.125 mol/kg, 9.158 g ZnSO4.1H.sub.2O, and 0.1275 mol/kg, 36.648 g GL-45-SLA (L-glutamic acid N,N-diacetic acid, tetra sodium salt, Na4-GLDA, Dissolvine GL-45-SLA, ex AkzoNobel). A clear solution was obtained at a pH of 5.27. The pH was not adjusted any further.

(8) The following 3 copper-containing solutions were prepared in the same way. CuSO.sub.4 0.125 mol/kg, 12.606 g CuSO.sub.4.5H.sub.2O were dissolved in de-mineralized water showing a clear solution with a pH of 3.64. The pH was not adjusted any further. Cu(Lysine).sub.2 0.125 mol/kg, 12.609 g CuSO.sub.4.5H.sub.2O, and 0.255 mol/kg, 18.686 g Lysine were dissolved in demineralized water. Within minutes a clear solution was obtained with a pH of 2.40. The pH was increased with NH.sub.4OH 2.5% up to pH 4.17. Cu-GLDA-Na.sub.2 0.125 mol/kg, 12.608 g CuSO.sub.4.5H.sub.2O, and 0.1275 mol/kg, 36.619 g GL-45-SLA. A clear solution was obtained at a pH of 5.04. The pH was adjusted to 4.97 with 0.5 M H.sub.2SO.sub.4.

(9) Then an equal number of 0.0125 mol/kg solutions were prepared by diluting the above solutions with demineralized water.

(10) This resulted in the following solutions: 7. 0.125 mol/kg ZnSO.sub.4 8. 0.0125 mol/kg ZnSO.sub.4 9. 0.125 mol/kg Zn(Lysine).sub.2 10.0.0125 mol/kg Zn(Lysine).sub.2 11.0.125 mol/kg Zn(Methionine).sub.2 12.0.0125 mol/kg Zn(Methionine).sub.2 13.0.125 mol/kg Zn-GLDA-Na.sub.2 14.0.0125 mol/kg Zn-GLDA-Na.sub.2 15.0.125 mol/kg CuSO.sub.4 16.0.0125 mol/kg CuSO.sub.4 17.0.125 mol/kg Cu(Lysine).sub.2 18.0.0125 mol/kg Cu(Lysine).sub.2 19.0.125 mol/kg Cu-GLDA-Na.sub.2 20.0.0125 mol/kg Cu-GLDA-Na.sub.2

(11) Combining Metal Salts and Phytic Acid

(12) On all 4 zinc-containing and 3 copper-containing solutions in total 6 precipitation tests were carried out, i.e. at levels H, M, and L and for each level at pH=4 and at pH=6. These tests were marked H4, H6, M4, M6, L4, and L6, respectively. In total 42 samples were obtained in this way. After standing for one day the precipitate was removed and the mother liquor was analyzed for its zinc or copper content by FAAS (Flame Atomic Absorption Spectroscopy). The detailed procedure is outlined below. 50 ml pre-weighted Greiner tubes were filled with the Phytic acid solutions and the intake exactly determined. The metal complex/chelate solutions were added and the intake exactly determined. The pH was adjusted with diluted NH.sub.4OH or H.sub.2SO.sub.4 solutions. Demineralized water was added to a total weight of 50 g and exactly determined. The tubes were mixed by hand until homogeneous. The tubes were left standing for one day at ambient temperature. The tubes were centrifuged when turbidity or sediment was noticed. The top layers of the centrifuged tubes and the clear solutions were filtered over a 0.45 μm filter and approximately 12 ml of the filtrate was put in a 15 ml pre-weighted Greiner tube. The intake was exactly determined and 1 ml of HNO3 1:1 was added to the solution. The total weight was exactly determined again.

(13) The 50 ml test tubes were filled according to Table 1 below.

(14) TABLE-US-00001 TABLE 1 Overview of test sample concentrations (PA = phytic acid) PA Metal PA Metal stock PA stock conc. conc. Sam- conc. stock conc. Metal test test ple Test mol/ intake mol/ stock sample sample code pH kg g kg intake g mmol/kg mmol/kg H4 4 0.125 20 0.125 10 50 25 H6 6 0.125 20 0.125 10 50 25 M4 4 0.05 10 0.0125 20 10 5 M6 6 0.05 10 0.0125 20 10 5 L4 4 0.005 10 0.0125 2 1 0.5 L6 6 0.005 10 0.0125 2 1 0.5

(15) Below the results are given for the zinc and copper concentrations of the mother liquor solutions after analysis by FAAS (Flame atomic absorption measurements).

(16) TABLE-US-00002 TABLE 2 Soluble Zn(II) in % (mol/mol) after subjecting complexed or chelated Zn(II) to a two-fold molar excess of phytic acid according to Table 1 Zinc source H4 H6 M4 M6 L4 L6 ZnSO.sub.4 20* 29* 51* 18* 96 58 Zn(Lysine).sub.2 22* 38* 49* 14* 95 37 Zn(Methionine).sub.2 21* 32* 55* 13* 99 63 Zn-GLDA-Na.sub.2 103  97  97  99  98 98 *Sediment or turbidity was noticed in the tube, therefore the tube was centrifuged.

(17) TABLE-US-00003 TABLE 3 Soluble Cu(II) in % (mol/mol) after subjecting complexed or chelated Cu(II) to a two-fold molar excess of phytic acid according to Table 1 Copper source H4 H6 M4 M6 L4 L6 CuSO.sub.4  64*  26*  97*  36* 97 80 Cu(Lysine).sub.2 103 102 98 98 99 97 Cu-GLDA-Na.sub.2 104 104 99 98 97 99 *Sediment or turbidity was noticed in the tube, therefore the tube was centrifuged.

(18) For both zinc and copper GLDA a clear solution was found at all 3 levels. In the case of zinc lysine and zinc methionine immediately a precipitate was formed, just as in the case of all the sulfate salts. In the case of copper-lysine also a clear solution was obtained, but despite a number of attempts copper methionine appeared to be insoluble in water even without the presence of phytate.

(19) Surprisingly, hardly any precipitate at all was formed in the experiments with GLDA.

(20) Unlike the other zinc and copper salts and amino acid complexes, surprisingly only copper-lysine gave rise to a clear solution.