Fish feed composition

Abstract

To provide: an improvement agent for feed efficiency of migratory fish at a low water temperature; a fish feed composition including the agent; and a fish farming method for the migratory fish using the agent.SOLUTION: There are provided: an improvement agent for feed efficiency of migratory fish at a low water temperature, the improvement agent including hot water extraction residue of roasted coffee beans as an active principle; a fish feed composition including hot water extraction residue of the roasted coffee beans, for allowing the migratory fish to ingest at a low water temperature; the fish feed composition containing the hot water extraction residue of the roasted coffee beans of 0.5 mass% or more in a solid content relative to the whole composition; and a farming method for the migratory fish, the method allowing the migratory fish to ingest the fish feed composition containing the hot water extraction residue of the roasted coffee beans at a low water temperature.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a composition for feeding fish that contributes to improving the feed efficiency of migratory fish at low water temperatures, and a method for farming fish by having them ingest the composition. [Background technology]

[0002] As feed for farmed fish, compound feed containing live bait or fish meal as the main ingredient is used. Various ingredients are mixed into the compound feed for the purpose of improving the health of the fish and the farming environment. For example, vitamins and minerals may be mixed in to compensate for nutritional deficiencies. Antibiotics and antibacterial agents may also be mixed in to prevent and treat diseases.

[0003] In recent years, due to the decline in fish catches and the need to protect water resources, the amount of raw bait and fish meal used has been reduced, and raw materials that can replace fish meal have been added. Examples of food materials that can be added as substitutes for fish meal include soybean oil cake, wheat flour, and corn gluten meal.

[0004] On the other hand, coffee drinks are a popular beverage that has been widely enjoyed for a long time and are industrially produced in large quantities. For this reason, from the perspective of the SDGs, various methods have been proposed for reusing the hot water extraction residue of roasted coffee beans, which is produced in large quantities every year. For example, a method has been disclosed in which the hot water extraction residue of roasted coffee beans itself is used as a substitute for fish meal (Patent Document 1). In addition, it has been reported that in flounder farming, a feed composition containing about 10% hot water extract of coffee beans can be used without adversely affecting growth or feed efficiency (Non-Patent Document 1).

[0005] In addition, the residue of hot water extraction of roasted coffee beans contains various physiological activities including caffeine, and in order to utilize these physiological activities, a small amount of the residue of hot water extraction of roasted coffee beans is added to a fish feed composition. For example, a method of blending a hot water extract of roasted coffee beans into a fish feed composition in order to reduce parasites that infest farmed fish has been disclosed (Patent Document 2). It has also been reported that in carp farming, blending a small amount of the residue of hot water extraction of roasted coffee beans into a fish feed composition improves the immunity of carp and reduces the effects of zinc toxicity and bioaccumulation in the fish body, without affecting the feed efficiency (Non-Patent Document 2). It has also been reported that cultivating tilapia with a fish feed composition blended with a hot water extract of roasted coffee beans can promote the growth of tilapia, improve feed efficiency, and improve immune function (Non-Patent Document 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2020-039260 A [Patent Document 2] Patent No. 5010809 [Non-patent literature]

[0007] [Non-Patent Document 1] Rahimnejad et al., Fisheries and Aquatic Sciences, 2015, vol.18(3), p.257-264. [Non-Patent Document 2] Abdel-Tawwab et al., Aquaculture, 2015, vol.448, p.207-213. [Non-Patent Document 3] Doan et al., Fish and Shellfish Immunology, 2022, vol.120, p.67-74. Summary of the Invention [Problem to be solved by the invention]

[0008] According to Non-Patent Document 2, feeding carp cultivated at an appropriate water temperature with hot water extract grounds of roasted coffee beans does not affect the feed efficiency, but according to Non-Patent Document 3, feeding tilapia with hot water extract grounds of roasted coffee beans improves the feed efficiency in tilapia cultivated at an appropriate water temperature. In other words, the effect of feeding carp with hot water extract grounds of roasted coffee beans varies depending on the type of fish. In addition, although Patent Documents 1-2 and Non-Patent Documents 1-3 describe the incorporation of a hot water extract or hot water extract residue of roasted coffee beans into a fish feed composition, there is no description of the effect of feeding the hot water extract residue to migratory fish.

[0009] An object of the present invention is to provide an agent for improving feed efficiency in migratory fish at low water temperatures, a fish feed composition containing said agent, and a method for cultivating migratory fish utilizing said agent. [Means for solving the problem]

[0010] As a result of intensive research aimed at solving the above-mentioned problems, the inventors discovered that by adding a small amount of hot water extraction residue from roasted coffee beans to a feed composition for migratory fish, feed efficiency at low water temperatures can be improved, and thus completed the present invention.

[0011] [1] An agent that improves feed efficiency in migratory fish in low water temperatures, containing the hot water extraction residue of roasted coffee beans as its active ingredient. [2] A fish feed composition containing hot water extraction residue of roasted coffee beans, for consumption by migratory fish when water temperatures are low. [3] The fish feed composition according to [2], wherein the content of hot water extraction residue of roasted coffee beans is 0.5 mass% or more in terms of solid content relative to the total composition. [4] The fish feed composition according to [2] or [3], wherein the migratory fish is a fish of the genus Seriola, Tuna, Salmon, or Scomber. [5] The fish feed composition according to [2] or [3], wherein the migratory fish is yellowtail, amberjack, or amberjack. [6] A method for cultivating migratory fish, comprising feeding the migratory fish with a fish feed composition containing hot-water extraction residue of roasted coffee beans when the water temperature is low. [7] The method for cultivating migratory fish according to [6] above, wherein the content of the hot water extraction residue of the roasted coffee beans in the fish feed composition is 0.5 mass% or more in terms of solid content relative to the entire composition. [8] The method for cultivating migratory fish according to [6] or [7] above, wherein the content of the hot water extraction residue of the roasted coffee beans in the fish feed composition is 2.0 mass% or less in terms of solid content relative to the total composition. [9] The method for cultivating migratory fish according to any one of [6] to [8] above, wherein the migratory fish is a fish of the genus Seriola, Tuna, Salmon, or Scomber.

[10] The method for cultivating migratory fish according to any one of [6] to [8] above, wherein the migratory fish is yellowtail, amberjack, or amberjack.

[11] The method for cultivating migratory fish according to any one of [6] to

[10] above, wherein the fish feed composition is ingested by migratory fish when the water temperature is 3° C. or more lower than an appropriate water temperature.

[12] The fish feed composition is ingested by migratory fish when the water temperature is 20.3°C or lower. The method for cultivating migratory fish according to any one of [6] to

[11] above. Effect of the Invention

[0012] The feed efficiency improver and the fish feed composition using the same according to the present invention can improve the feed efficiency of migratory fish at low water temperatures. Therefore, the present invention can reduce the amount of feed required and economically and efficiently farm migratory fish. Furthermore, the feed efficiency improver contains hot water extraction grounds of roasted coffee beans as an active ingredient, and is also useful in terms of the SDGs by reusing hot water extraction grounds of roasted coffee beans. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] In the present invention and the present specification, "coffee hot water extraction grounds" refers to the residue obtained by extracting roasted coffee beans with hot water, and may also be called "coffee dregs" or "coffee grounds". In other words, it is the residue obtained by removing at least a portion of the water-soluble solid content from the roasted coffee beans. The coffee hot water extraction grounds may contain the water-soluble solid content of the roasted coffee beans.

[0014] In the present invention and this specification, the term "migratory fish" refers to fish that move across wide ocean areas or between seas and rivers depending on the growth stage and changes in the environment.

[0015] In the present invention and this specification, "low water temperature" means that the water temperature in which the fish grows is at least 3°C ​​lower than the optimum water temperature for the fish. The "optimum water temperature" for a fish means the water temperature at which the fish will grow at its maximum. Furthermore, the "water temperature at which the fish grows" means the maximum water temperature in one day of the environmental water in which the fish grows.

[0016] In the present invention and the present specification, the "feed efficiency" of fish means the ratio of weight gain to the amount of feed intake of fish. Specifically, it is calculated by the following formula. The "amount of feed consumed" means the dry weight (g) of the feed ingested.

[0017] [Feed efficiency (%)] = ([body weight at the end of the measurement (g)] - [body weight at the start of the measurement (g)]) / [amount of feed consumed during the measurement period (g)] × 100 (%)

[0018] The feed efficiency improver according to the present invention is ingested by migratory fish to improve the feed efficiency at low water temperatures, and contains hot water extract dregs of roasted coffee beans as an active ingredient. From the viewpoint of aquaculture efficiency, it is important to grow fish to a size that can be shipped quickly with a smaller amount of feed, and improving feed efficiency is an important issue. On the other hand, fish are easily affected by water temperature, and in a water temperature environment lower than the optimum water temperature, metabolism decreases, food intake also decreases, and feed efficiency decreases. In response to this, by containing an appropriate amount of hot water extract dregs of roasted coffee beans in a fish feed composition, the feed efficiency of migratory fish at low water temperatures can be improved. That is, the method for cultivating migratory fish according to the present invention is a method in which a fish feed composition containing hot water extract dregs of roasted coffee beans is ingested by migratory fish at low water temperatures.

[0019] The reason why the hot water extract of roasted coffee beans improves the feed efficiency of migratory fish in low water temperatures is unclear, but the hot water extract of roasted coffee beans contains ingredients that activate the metabolism of migratory fish, and it is speculated that this is due to the metabolic promotion effect of these ingredients. On the other hand, when migratory fish are fed hot water extract of roasted coffee beans when the water temperature is optimal, the feed efficiency actually decreases. This is speculated to be because, at optimal water temperatures, the excess energy produced by the metabolic promotion caused by the hot water extract of roasted coffee beans is used for exercise, and does not lead to weight gain.

[0020] The hot water extraction grounds of roasted coffee beans used in the present invention are residues obtained after extracting water-soluble solids by contacting roasted coffee beans or ground products thereof with heated water. The extraction method of the water-soluble solids can be performed by a method generally used when brewing coffee or a method used when extracting soluble solids from ground products of roasted coffee beans when producing instant coffee. Specifically, any of drip, espresso, siphon, percolator, coffee press (French press), column, etc. may be used. Extraction may be performed by normal pressure or pressurized. In addition, the coffee hot water extraction grounds may be the residue after performing hot water extraction only once, or may be the residue after performing hot water extraction multiple times. The temperature and pressure conditions of hot water extraction from roasted coffee beans are not particularly limited. For example, it may be coffee hot water extraction grounds obtained by extraction under normal pressure (atmospheric pressure) at 100°C or less, or it may be coffee hot water extraction grounds obtained by extraction under high temperature and high pressure conditions, for example, under pressure at more than 100°C and 250°C or less.

[0021] The roasted coffee beans for obtaining the hot water extraction dregs used in the present invention are not particularly limited in type or origin of coffee beans, and may be Arabica, Robusta, or a blend of two or more varieties of coffee beans. The roasting method is also not particularly limited, and may be any method generally used for roasting coffee beans. Examples of the roasting method for coffee beans include direct fire roasting, hot air roasting, far infrared roasting, charcoal roasting, microwave roasting Liberica, etc.

[0022] The roasting degree of the roasted coffee beans for obtaining the hot water extraction grounds used in the present invention is not particularly limited, and may be very light roast, light roast, medium roast, or dark roast. The grinding degree of the roasted coffee beans is not particularly limited, and roasted coffee beans of various shapes such as coarsely ground, medium-coarsely ground, medium ground, medium-fine ground, and fine ground can be used.

[0023] The hot water extraction grounds of roasted coffee beans used in the present invention are preferably pulverized. The pulverization can be carried out using a general pulverizer such as a roll mill.

[0024] The hot water extraction residue of roasted coffee beans used in the present invention can be concentrated by removing liquid components, and may be solidified by completely removing the liquid components. The liquid components can be removed by appropriately using a method generally used for removing water or solvents, such as a reduced pressure distillation method using an evaporator. The hot water extraction residue of roasted coffee beans contained in the fish feed composition is preferably in a solid form such as powder or granules, since it has good storage stability and is easy to adjust the amount added to the fish feed composition.

[0025] The fish feed composition according to the present invention is a feed composition for migratory fish to ingest at low water temperatures, and contains roasted coffee bean hot water extract dregs. The content of the roasted coffee bean hot water extract dregs in the fish feed composition according to the present invention is not particularly limited as long as it is a sufficient amount to achieve the effect of improving the feed efficiency of migratory fish at low water temperatures due to the hot water extract dregs. For example, the content of the roasted coffee bean hot water extract dregs is preferably 0.4% by mass or more, more preferably 0.5% by mass or more, in terms of solid content, relative to the entire composition of the fish feed composition. In addition, if the content of the roasted coffee bean hot water extract dregs is too high, there is a risk that the feed efficiency will be reduced. Therefore, the content of the roasted coffee bean hot water extract dregs in the fish feed composition according to the present invention is preferably 5% by mass or less, more preferably 2.5% by mass or less, and even more preferably 2.0% by mass or less.

[0026] The fish feed composition according to the present invention can be prepared by adding an appropriate amount of hot water extraction residue of roasted coffee beans to fish feed generally used for culturing migratory fish. The fish feed can be produced by a conventional method using raw materials such as animal proteins such as live bait and fish meal; grains such as wheat flour and various starches; vegetable proteins such as wheat gluten, corn gluten meal, soybean meal, rapeseed meal; lipid materials such as soybean oil cake and rapeseed oil cake; yeasts, seaweed powder, vitamins, minerals, amino acids, and various additives. The additives are not particularly limited as long as they are substances generally blended in fish feed compositions, and include, for example, excipients, binders, spreaders, flow improvers (anti-caking agents), stabilizers, preservatives, pH adjusters, solubilizers, diluents, suspending agents, emulsifiers, thickeners, and the like, and may also be antibiotics, antibacterial agents, immunoactivators, and the like. These additives may be produced by conventional methods.

[0027] The shape of the fish feed composition according to the present invention is not particularly limited. For example, it can be prepared in the form of moist pellets, dry pellets, extruder pellets, etc. These forms can be produced by conventional methods.

[0028] Examples of migratory fish that can be fed the fish feed composition according to the present invention to improve feed efficiency at low water temperatures include fish of the Seriola genus, such as yellowtail (Seriola quinqueradiata Temminck & Schlegel), yellowtail amberjack (Seriola lalandi Valenciennes), amberjack (Seriola dumerili), long-fin amberjack (Seriola rivoliana Valenciennes), and southern amberjack (Seriola hippos Guenther); fish of the Thunnus genus, such as bluefin tuna (Thunnus orientalis), Atlantic bluefin tuna (Thunnus thynnus), southern bluefin tuna (Thunnus maccoyii), bigeye tuna (Thunnus obesus), and albacore tuna (Thunnus alalunga); salmon (Oncorhynchus keta), coho salmon (Oncorhynchus fish of the genus Oncorhynchus, such as Oncorhynchus kisutch and Oncorhynchus nerka; fish of the genus Scomber, such as Scomber japonicus, Scomber australasicus, and Scomber scombrus. In the present invention, the migratory fish for which the feed efficiency at low water temperatures is improved is preferably fish of the genus Seriola, and more preferably Seriola amberjack, Amberjack, or Amberjack, because they are widely cultivated and there is a strong demand for improved feed efficiency. In the present invention, particularly when culturing Seriola amberjack, Amberjack, or Amberjack when the water temperature is 20.3°C or lower, the feed efficiency can be improved by feeding the fish with the fish feed composition of the present invention. EXAMPLES

[0029] Next, the present invention will be described in more detail by showing examples, but the present invention is not limited to the following examples.

[0030] <Evaluation of rearing results> In the following experiments, the items used to evaluate the rearing results in aquaculture were body weight (g), weight gain rate (%), feed efficiency (%), daily feeding rate (%), and survival rate (%). For statistics, a T-test was used, and judgments were made at a critical level of 0.05 or 0.1. Note that "total amount of feed" and "feed intake" are both dry weights.

[0031] [Weight gain rate (%)] = ([Total weight at the end of the experiment (g)] - [Total weight at the start of the experiment (g)]) / [Total weight at the start of the experiment (g)] x 100 (%)

[0032] [Feed efficiency (%)] = ([Total body weight at the end of the experiment (g)] - [Total body weight at the start of the experiment (g)]) / [Total feed amount (g)] × 100 (%)

[0033] [Daily feeding rate (% / BW / day)] = 100 x [feeding amount (g)] / ([total number of fish at the start of the experiment] + [total number of fish at the end of the experiment]) / 2 x ([average body weight at the end of the experiment (including dead fish; g)] + [(average body weight at the start of the experiment (g)] / 2 x [number of days of feeding (days)]

[0034] [Survival rate (%)] = [Number of fish at the end of the test] / [Number of fish at the start of the test] x 100 (%)

[0035] [Example 1] Coffee grounds extracted with hot water were added to a feed composition and the effect on the feeding behavior of cultured yellowtail was investigated.

[0036] <Preparation of hot water coffee grounds> Roasted coffee beans (50% by mass of Arabica and 50% by mass of Robusta) were ground. The resulting ground material was extracted with hot water to obtain hot water coffee grounds. The extraction was performed using a drip coffee machine (c-22 Premium Brewing System, manufactured by BREW MATIC) with 1138 g of hot water per 60 g of ground roasted coffee beans. The Brix yield of the obtained extract was 25.4% by mass (average value). The obtained hot water coffee grounds (coffee powder after hot water extraction) were spread on a metal tray and dried in a thermostatic oven so that the moisture content after drying was less than 1% by mass. The dried hot water coffee grounds were re-ground when preparing the feed to adjust the particle size.

[0037] <Preparation of fish feed composition> A feed composition containing hot-water extract grounds was prepared by mixing carboxymethylcellulose as a spreading agent at 1% by mass and the coffee hot-water extract grounds obtained above at 0.5% by mass with a commercially available yellowtail feed (EP6, Nisshin Marubeni Feed Co., Ltd.). As a control feed, a feed composition not containing hot-water extract grounds was prepared in the same manner except that the coffee hot-water extract grounds were not added.

[0038] <Aquaculture at low water temperatures> Eight yellowtails weighing 142.0g on average were housed in each of six 1.1-ton FRP tanks. The fish were fed either a hot-water extract lees-containing feed composition or a hot-water extract lees-free feed composition once a day until they were full. The rearing period was nine weeks, and measurements were taken every three weeks. During this period, the water temperature rose from 18.0°C to 21.9°C. The measurement results are shown in Table 1. In the table, "Control" indicates the results for the group that ingested the hot-water extract lees-free feed composition, and "CG0.5" indicates the results for the group that ingested the hot-water extract lees-containing feed composition.

[0039] [Table 1]

[0040] No fish died throughout the test period, and the survival rate was 100% in all tanks. In addition, compared to the control group (the group that ingested the feed composition that did not contain hot water extract dregs), the group that ingested the feed composition that did not contain hot water extract dregs had significantly improved average body weight, feed intake, weight gain rate, and feed efficiency. This trend continued until 6 weeks later (water temperature 20.3°C). After 9 weeks (21.9°C), the significant differences in all items had disappeared.

[0041] [Example 2] A feed composition containing coffee grounds extracted with hot water was added to investigate its effect on feeding behavior during high and low temperature periods in culture of yellowtail.

[0042] Five types of feed compositions (moist pellets) were prepared with the compositions shown in Table 2. In the table, "EP No. 6" represents a commercially available yellowtail feed (EP No. 6, manufactured by Nisshin Marubeni Feed Co., Ltd.). The coffee hot water extract grounds used were those prepared in Example 1. Specifically, carboxymethylcellulose and coffee hot water extract grounds as a spreading agent were mixed with 50 mL of water into 1 kg of yellowtail EP feed (Nisshin Marubeni Feed Co., Ltd.).

[0043] [Table 2]

[0044] <Aquaculture during high temperatures> Ten 1.1-ton FRP tanks were filled with five current-year yellowtail fish (252.8 g each). The test period was three weeks from November 18, 2022 to December 8, 2022. During this period, the test fish were fed once a day, six days a week, until they were satiated. The water temperature during the test period was 23.2°C at the start of the test and 22.3°C at the end of the test.

[0045] The results of body weight and other tests were analyzed using one-way ANOVA followed by Tukey multiple range test to determine significant differences between test intervals (p<0.05). The evaluation results are shown in Table 3.

[0046] [Table 3]

[0047] As shown in Table 3, the area where coffee hot water extract grounds were added at 0.5% (CG0.5) showed a significant decrease in growth compared to the control area where no coffee hot water extract grounds were added (Control). A tendency for decreased growth performance was also observed in the areas where coffee hot water extract grounds were added at 1% (CG1.0) and 2% (CG2.0).

[0048] <Cultivation during the low water temperature period> Six current year yellowtail fish (360.1g) were housed in each of ten 1.1 ton FRP tanks. The test period was eight weeks from January 13, 2023 to March 10, 2023. During this period, the test fish were fed once a day, six days a week, until they were satiated. The water temperature during the test period was 19.2°C at the start of the test and 16.8°C at the end of the test.

[0049] The results of growth and other outcomes after 8 weeks were examined using one-way ANOVA followed by Tukey multiple range test to determine significant differences between test sections (p<0.05). Changes in body weight were examined using two-way ANOVA followed by Tukey multiple range test to determine significant differences between test sections (p<0.05). The evaluation results are shown in Table 4.

[0050] [Table 4]

[0051] As shown in Table 4, the group supplemented with 0.5% coffee hot water extract grounds (CG0.5) showed a significant increase in body weight and growth compared to the control group (Control), and feed efficiency was also significantly improved. A tendency for feed efficiency to improve was also observed in the groups supplemented with 1% coffee hot water extract grounds (CG1.0) and 2% coffee hot water extract grounds (CG2.0).

Claims

1. An agent that improves feed efficiency in migratory fish in low water temperatures, containing hot water extraction residue from roasted coffee beans as its active ingredient.

2. A fish feed composition containing hot water extraction residue of roasted coffee beans, for ingestion by migratory fish when the water temperature is low.

3. The fish feed composition according to claim 2 , wherein the content of the hot water extraction residue of roasted coffee beans is 0.5 mass% or more in terms of solid content relative to the entire composition.

4. The fish feed composition according to claim 2 or 3, wherein the migratory fish is a fish of the genus Seriola, Tuna, Salmon, or Scomber.

5. The fish feed composition according to claim 2 or 3, wherein the migratory fish is yellowtail, amberjack, or amberjack.

6. A method for cultivating migratory fish, comprising feeding the migratory fish with a fish feed composition containing residue obtained by hot-water extraction of roasted coffee beans when the water temperature is low.

7. The method for cultivating migratory fish according to claim 6, wherein the content of the hot water extraction residue of the roasted coffee beans in the fish feed composition is 0.5 mass% or more in terms of solid content relative to the entire composition.

8. The method for cultivating migratory fish according to claim 6, wherein the content of the hot water extraction residue of the roasted coffee beans in the fish feed composition is 2.0 mass% or less in terms of solid content relative to the entire composition.

9. 8. The method for cultivating migratory fish according to claim 6 or 7, wherein the migratory fish is a fish of the genus Seriola, Tuna, Salmon, or Scomber.

10. The method for cultivating migratory fish according to claim 6 or 7, wherein the migratory fish is yellowtail, amberjack, or amberjack.

11. 8. The method for cultivating migratory fish according to claim 6 or 7, wherein the fish feed composition is ingested by migratory fish when the water temperature is 3° C. or more lower than an appropriate water temperature.

12. 8. The method for cultivating migratory fish according to claim 6 or 7, wherein the fish feed composition is ingested by migratory fish when the water temperature is 20.3°C or lower.

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