GB2249466A - Feed for aquatic farming and process for preparing the same - Google Patents

Abstract

A feed composition for aquatic farming consists essentially of at least one of water-soluble amino acids coated with at least one of fats and oils, and water-soluble amino acid derivatives coated with at least one of fats and oils. Also disclosed are a process for preparing the same comprising coating, an artificial feed composition comprising said feed composition as an essential component, and a process for preparing the same comprising molding.

Description

FEED FOR AQUATIC FARMING AND PROCESS FOR PREPARING THE SAME The present invention relates to feed compositions for aquatic farming and processes for preparing the same.

Aquatic farming includes limnetic farming and marine farming.

At the present time, feed used for artificial cultivation of aquatic animals, i.e., aquatic farming, consists of approximately 50% of artificial feed and the balance of natural feed such as frozen sardines, etc.

In respect of such natural feed, its intake ratio is as low as about 30% and the remaining 70% is lost in water. In addition, the area for breeding natural aquatic foods used as feed requires several times the area for artificial cultivation of aquatic animals. To ensure the former area, reckless deforestation at the water front is induced in South Eastern Asia and such might lead to environmental pollution and disruption.

Furthermore, the natural feed is decreasing yearly and its costs are increasing.

On the other hand, few kinds of artificial feed are satisfactory in respect of physical properties. For this reason, a poor feed efficiency, water pollution, etc.

caused by dissolution of the contents have become serious problems.

Water-soluble amino acids such as arginine and lysine are used as useful feed ingredients in feed for mammals, etc. However, it is the actual situation that because of their water solubility, a feed efficiency is poor and these amino acids are not effectively utilized for aquatic animals.

The present invention has been made to overcome shortcomings of conventional natural feed and/or artificial feed and provides feed for aquatic farming having good physical properties and a high feed efficiency without dissolving out the contents, and a process for preparing the same in a simple procedure.

As a result of extensive investigations to solve the problems described above, the present inventors have found that by covering water-soluble amino acids with oils and fats, artificial feed for aquatic farming having good physical properties, free of environmental pollution because of no dissolution of the contents, having a slow releasability and a high feed efficiency even for aquatic animals with short intestinal tract, can be obtained in a simple procedure at low costs, and have come to accomplish the present invention on the basis of these findings.

This invention provides a feed composition for aquatic farming consisting essentially of at least one of watersoluble amino acids coated with at least one of fats and oils, and water-soluble amino acid derivatives coated with at least one of fats and oils. The invention also provides a process for preparing the feed composition comprising coating, an artificial feed composition comprising the feed composition as an essential component, and a process for preparing the same comprising molding.

That is, the present invention relates to (raw) feed material for aquatic farming consisting essentially of water-soluble amino acid(s) and/or water-soluble amino acid derivative(s) coated with oils and/or fats, and a process for preparing the same, as well as a feed composition for aquatic farming comprising as an essential component water-soluble amino acid(s) and/or water-soluble amino acid derivative(s) and a process for preparing the same.

Examples of the water-soluble amino acid which can be used in accordance with the present invention include arginine, lysine, methionine, tryptophan, threonine, etc.

The water-soluble amino acids may be in the form of the derivatives thereof, for example, hydrochloride, etc. or a mixture thereof. In respect of the shape, though it is preferably as close as spherical, it is not necessarily limited to the spherical shape.

The oils and fats used in accordance with the present invention include oils and fats which are solid at ambient temperature, for example, vegetable oils, hydrogenated oils and fats such as palm oil, hydrogenated palm oil, palm kernel oil, coconut oil, hydrogenated corn oil, hydrogenated soybean oil and hydrogenated linseed oil, and animal oils, hydrogenated oils and fats such as lard and beef fat; waxes which are solid at ambient temperature such as carnauba wax; fatty acids which are solid at ambient temperature such as stearic acid; and mixtures thereof. In other words, in this specification, especially in the claims, the term "oils and fats" is defined as comprising not only so-called oils and fats but also waxes and fatty acids having the same coating function as the so-called oils and fats for the purpose of the present invention.

In accordance with the present invention, the watersoluble amino acid(s) and/or derivative(s) thereof and the oils and/or fats are used in a weight ratio of 90 to 30% of the former ingredient(s) to 10 to 70% of the latter ingredient(s), and preferably 70 to 50% to 30 to 50%. Where the oils and/or fats are used in smaller amounts than the lower limit, there is a fear that coating might be insufficient; where the oils and/or fats are used in larger amounts than the upper limit, coating might be excessive and the intake of oils and/or fats might be excessive. The ratio described above may be varied depending upon animals for aquatic farming to be fed. That is, it is possible to control the coating state by reducing or increasing the coating thickness so as to fit the optimum release time of the amino acid depending on each animal.Its degree may be varied depending upon occasion but in general, may not be so complete. Where coating is made completely in such an extent that no pinholes are present at all, there is a fear that the amino acid might not be released.

The preparation apparatus which can be used in accordance with the present invention may be any of wet fluidized bed coating type, dry surface modification type and other known types. The desired (raw) feed material for aquatic farming or the desired feed composition for aquatic farming may be obtained using any of these apparatuses.

The preparation process according to the present invention comprises, in the case of the wet type process, previously charging the water-soluble amino acid(s) or derivative(s) thereof as the core material in the apparatus to fluidize, and coating with the oil or fat as the coating agent which has been melted by heating at a temperature above the melting point. In order to obtain the feed of the desired standard, it is necessary to control a feeding rate of the oil or fat. This is because when the flow rate is too fast, the amino acid being coated with the oil or fat forms undesirable lumps and conversely where the flow rate is too slow, an operation efficiency is poor, and so on. A suitable flow rate varies depending on the kind of the core material and oils and fats, the particle diameter and shape of the core material, the kind of apparatus, production scale, etc. and can be set out appropriately on the basis of these factors.

In the case of the dry type process, the feed can be obtained by previously blending an oil or fat as the coating agent and water-soluble amino acid(s) or derivative(s) thereof as the core material, and then treating the blend with a surface modification apparatus such as a Hybridizer manufactured by Nara Kikai Seisakusho. In order to obtain feed of the desired standard, the operation conditions can be appropriately set forth.

The feed for aquatic farming in accordance with the present invention may be used as it is obtained, by adding to and blending with other artificial feed, or by molding together with other artificial feed ingredients.

The particle diameter and size are usually set to 2 mm in diameter and 2 mm in length but may be set forth depending upon each animal concerned. The thus obtained feed (raw) material for aquatic farming or feed composition for aquatic farming may be sieved into the desired particle diameter and provided for use, if necessary.

As the other artificial feed ingredients, there may be exemplified rice bran, starch, wheat flour, soybean meal, lecithin, minerals, lime, etc. which are generally used in appropriate combinations.

The animals for aquatic farming to which the feed of the present invention can be fed include crustacea, e.g., prawns, shrimps, etc.; fish, e.g., sea breams, yellowtails, salmons, trout, rainbow trout, flatfish, eels, ayu fish or sweetfish, etc., and any other aquatic animals which are artificially cultivated.

By coating water-soluble amino acid(s) or derivative(s) thereof with an oil or fat, feed for cultivating aquatic animals having good physical properties, free of environmental pollution and having a high feed efficiency, and feed compositions comprising the same as an essential component can be obtained in a simple procedure at low costs.

Examples Hereinafter the present invention is described in detail with reference to examples thereof, to specifically illustrate the characteristics of the present invention.

Example 1: Preparation of (raw) feed material for aquatic farming (wet type process) Into a wet type fluidized coating apparatus, SPIRA COTA manufactured by Okada Seiko K.K., was charged 1 kg of L-arginine hydrochloride. 1 kg of maximally hardened palm oil which had been completely melted at 800C was introduced into the apparatus having a fluidized bed temperature of 30 to 400C at a flow rate of 0.9 g/min over about 19 hours whereby the arginine hydrochloride was coated with this palm fat.

Thus, 1.6 kg of the fat-coated arginine was obtained.

Example 2: Preparation of (raw) feed material for aquatic farming (dry type process) 150 g of L-lysine hydrochloride and 45 g of carnauba wax were previously blended for 5 minutes with an OM DIZER (manufactured by Nara Kikai Seisakusho).

Using a Hybridizer HYB-1 (manufactured by Nara Kikai Seisakusho), 180 g of the resulting blend was subjected to surface modification for 3 minutes at a rotation number of 4800 RPM to give 135 g of the fat-coated lysine was obtained.

Example 3: Preparation of (raw) feed material for aquatic farming (dry type process) Using 150 g of L-arginine hydrochloride and 30 g of carnauba wax as raw materials, the same procedure as in Example 2 was carried out to give 125 g of the fat-coated arginine.

Example 4: Preparation of feed composition for aquatic farming After 1.6 kg of the fat-coated L-arginine hydrochloride prepared in Example 1 had been thoroughly blended with the respective components shown in Table 1 in the compositional ratio as shown, the blend was passed through a meat grinder. The blend was pushed out of the grinder spaghetti-like to give pellets. The pellets were dried at 40 to 450C for 4 hours until the water content became 12% or less.

Thus, a feed composition for aquatic farming was prepared, containing 1.4% on the dry basis of the fatcoated L-arginine hydrochloride as a raw feed material.

A comparative feed composition was prepared similarly, but using non-coated L-arginine hydrochloride instead of the coated L-arginine hydrochloride.

A control feed composition was prepared similarly, but using neither the coated nor the non-coated Larginine hydrochloride.

Both in the inventive and the comparative composition, the increment by the arginine moiety was compensated with the decrement in rice starch.

Table 1. Artificial Feed Compositions for Prawn Culture

Composition Component of the Comparative Control Present Composition Composition Invention Rice bran 6(wt%) 6(wt%) 6(wt%) Rice starch 2.1 2.8 3.5 Wheat flour 20 20 20 Wheat gluten 5 5 5 Prawn head meal 20 20 20 Squid meal 5 5 5 Soybean meal 10 10 10 Fish meal 30 30 30 Squid liver oil 2 2 2 Lecithin 1 1 1 Vitamin mixture 1 1 1 Mineral mixture 5 5 5 Zeolite 1.5 1.5 1.5 Fat-coated L- 1.4 0 arginine 1.4 hydrochloride Non-coated L arginine 0.7 0 hydrochloride Nutritional Composition Crude protein 45.44 45.88 44.31 Oil and fat 8.88 8.56 7.85 Example 5: Evaluation using prawn fry (Marine farming) The three artificial feed compositions having the respective components ratios shown in Table 1 were each fed to three test groups of prawn fry, respectively, for 8 weeks.

The results of the evaluation test are shown in Table 2, in terms of weight gain of prawns as a whole per a water tank unit. The weight gain was significantly higher in the group fed with the artificial feed composition of the present invention, than in the comparative group and the control group.

Table 2. Results of Comparison in Weight Gain as the Whole Prawns per a Water Tank Unit

Week 0 2 4 6 8 Inventive 3.60 10.60 20.89 35.41 53.79 Comparative 3.59 10.20 18.58 28.49 41.53 Control 3.62 9.73 18.92 30.11 41.40 (g/water tank) Example 6: Evaluation using rainbow trout juvenile (Limnetic farming) Three artificial feed compositions having the respective components ratios shown in Table 3 were prepared and fed to three test groups of 20 rainbow trout juvenile, respectively, for feeding test.

The inventive feed composition contained 0.6% of the fat-coated L-lysine hydrochloride obtained in Example 2; the comparative composition contained 0.5% crystalline Llysine hydrochloride not coated with any oil or fat; and the control feed composition contained neither the oil or fat-L-lysine hydrochloride nor crystalline L-lysine hydrochloride was fed. Both in the inventive and the comparative feed composition, the amount of wheat starch was reduced by the amount corresponding to the added fatcoated L-lysine hydrochloride and crystalline L-lysine hydrochloride, respectively.

Table 3. Feed Compositions for Culturing Rainbow Trout Juvenile

Inventive Comparative Control Component Composition Composition Composition (wt) (wt%) (wt) Fish meal 50 50 50 Soybean meal 5 5 5 Corn gluten meal 10 10 10 Yeast (dried) 3 3 3 Wheat flour 20 20 20 Wheat starch 3.4 3.54 4 Rice bran 5 5 5 Calcium phosphate 1 1 1 Sodium chloride 1 1 1 Fish oil 1 1 1 Fat-coated L lysine 0.6 0 0 hydrochloride Crystalline L- 0 0.46 0 lysine hydrochloride Total 100 100 100 Twenty rainbow trouts weighing 1.1 g on the average were allotted in each test aquarium of 100 liters and cultivated in a running water system.

The results of evaluation are shown in Table 4, in terms of average body weight of the 20 rainbow trout.

The body weight gain was significantly greater in the inventive group than in the control group and in the comparative group.

Table 4. Comparison in the Average Body Weight of Rainbow Trout (Unit: trams)

Week 0 2 4 6 8 10 Inventive 1.1 1.8 2.6 4.2 5.3 7.5 Comparative 1.1 1.8 2.5 4.0 5.1 6.1 Control 1.1 1.8 2.4 4.0 5.2 6.0 The feed for aquatic farming obtained in accordance with the present invention can be provided at low costs in a simple procedure as artificial feed for cultivation of aquatic animals having good physical properties, free of environmental pollution and having a high feed efficiency, which has overcome, by coating water-soluble amino acid(s) or derivative(s) thereof with fat and/or oil, the problems of environmental disruption to ensure a breeding area of living things as natural feed which requires a space due to poor intake of natural feed, and increased costs caused by decrease in natural feed, a poor feed efficiency or water pollution because of dissolution of the contents of artificial feed, and as the feed composition for aquatic farming comprising the said artificial feed as an essential component.

Therefore, the present invention contributes not only to the market but also to the environment.

Claims (6)

1. A feed composition for aquatic farming comprising at least one of water-soluble amino acids coated with at least one of fats and oils and water-soluble amino acid derivatives coated with at least one of oils and fats.

2. A process for preparing the feed composition of Claim 1, which comprises coating at least one of watersoluble amino acids and water-soluble amino acid derivatives with at least one of oils and fats.

3. An artificial feed composition comprising as an essential component the feed composition of Claim 1.

4. A process for preparing the artificial feed composition of Claim 3, which comprises molding the feed composition of Claim 1 together with other artificial feed ingredients.

5. A feed composition for aquatic farming substantially as described herein in any of Examples 1 to 4.

6. A process for preparing a feed composition for aquatic farming substantially as described herein in any one of Examples 1 to 4.