Formulated feed for aquatic animals and method for producing formulated feed for aquatic animals

Abstract

To provide a formulated feed for aquatic animals and a method for producing the formulated feed for aquatic animals, which enable sufficient growth of aquatic animals even when fish meal is not added.SOLUTION: A formulated feed for aquatic animals comprises a paste of marine Brachionus plicatilis and related strains.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a compound fish and shellfish feed and a method for producing a compound fish and shellfish feed. [Background technology]

[0002] Fishmeal is generally used as the main protein source in compound feed for seafood. Fishmeal is produced from wild caught horse mackerel and anchovy. As the amount of farmed seafood production increases worldwide, the consumption of fishmeal is also increasing. The amount of resources has not increased, making it difficult to secure a stable supply of raw materials, and the increasing demand for fishmeal has caused the price of fishmeal to soar.

[0003] Potential alternative protein sources include vegetable proteins such as soybean oil meal and corn gluten meal, animal food residue proteins made by crushing the edible parts of feather meal and birds, and insects such as black soldier flies, crickets, and mealworms. However, it has been pointed out that vegetable proteins can have adverse effects on seafood, such as amino acid deficiencies, delayed absorption, and lack of nutrients. Disadvantages of animal food residue proteins include fat spoilage and bacterial contamination. Insects are expensive, and there is a strong psychological resistance to them.

[0004] Patent Document 1 discloses a method for producing feed for aquatic animals using marine rotifers (hereinafter also referred to as "rotifers") as a raw material. Non-Patent Document 1 evaluates the feed value of Brachionus plicatilis for red sea bream larvae. Patent Document 2 discloses a feed additive consisting of rotifers or aerobic biologically treated sludge containing rotifers. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-180377 A [Patent Document 2] JP 2014-113131 A [Non-patent literature]

[0006] [Non-Patent Document 1] Tsutomu Tomoda and 4 others, “Feed value of rotifer Brachionus plicatilis at different reproductive stages for red sea bream larvae”, Journal of the Japanese Society of Fisheries Science, 70(4), 573-582, 2004 Summary of the Invention [Problem to be solved by the invention]

[0007] The method for producing feed for aquatic animals disclosed in Patent Document 1 is useful for producing feed for larvae of detritivorous aquatic animals, but rotifers are not considered as a protein source for compound feed for seafood. The rotifers in Patent Document 2 are considered as a feeding promoter to improve palatability, and rotifers are not included as a protein source. In Non-Patent Document 1, rotifers are fed to sea bream larvae without processing, and rotifers are not evaluated as a raw material for compound feed.

[0008] The present invention has been made in consideration of the above-mentioned situation, and aims to provide a fishery feed compound that allows fishery products to grow sufficiently without the addition of fish meal, and a method for producing the fishery feed compound. [Means for solving the problem]

[0009] The fish and shellfish mixed feed according to the first aspect of the present invention comprises: Contains a paste of marine rotifers.

[0010] The paste is 75% by weight or more. This may also be the case.

[0011] The fish and shellfish mixed feed according to the first aspect of the present invention is For young fish, This may also be the case.

[0012] The method for producing a fish and shellfish compound feed according to the second aspect of the present invention comprises the steps of: a washing step of washing the cultured marine rotifers; A pasting step of removing at least a portion of the water from the marine rotifers to obtain a paste; a drying step of drying the paste to obtain a powder; A blending step of blending the powder into a fish and shellfish feed; Includes.

[0013] The marine rotifers washed in the washing step include The study included multiple marine rotifers cultured on different diets. This may also be the case.

[0014] The bait is At least one selected from the group consisting of green algae, haptophytes and diatoms; This may also be the case. Effect of the Invention

[0015] According to the present invention, fish and shellfish can be grown satisfactorily without adding fish meal. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is a graph showing the average body weight of red sea bream fed the feed according to Example 1. [Diagram 2] FIG. 13 is a graph showing the average body weight of yellowtail fed with the feed according to Example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the following embodiments and drawings. Note that in the following embodiments, the expressions "have", "include" and "contain" also include the meaning of "consisting of" or "consisting of".

[0018] The compound feed according to the present embodiment is used as bait for fish and shellfish. Fish and shellfish broadly include marine animals. There are no particular limitations on the fish and shellfish, and examples include red sea bream, yellowtail, flounder, tuna, horse mackerel, pufferfish, shrimp, oysters, and scallops. The compound feed according to the present embodiment can be used for any of larvae, fry, and adult fish, but is preferably for fry.

[0019] The compound feed according to the present embodiment includes a paste of rotifers. The rotifers are not particularly limited, and examples thereof include L-type (Brachionus plicatilis OFMullre), S-type (Brachionus rotundiformis Tschugunoff), Brachionus plicatilis sp.complex L-type Obama strain, SS-type and S-type Yaeyama strain, etc.

[0020] The rotifers may be commercially available or may be cultured by a known method. Methods for culturing rotifers include subculture, outdoor culture, thinning culture, and high-density culture. In culturing rotifers, microalgae are preferably fed. The microalgae are not particularly limited as long as they can be used as food for rotifers, but preferred examples include green algae, cryptoalgae, haptoalgae, and diatoms.

[0021] Examples of green algae include Chlorella, Dunaliella, Haematococcus, etc. Preferably, the green algae is Chlorella vulgaris.

[0022] Examples of cryptoalgae include Cryptomonas, Rhodomonas, and Chroomonas.

[0023] Examples of haptophytes include Tisochrysis lutea, Isochrysis sp., Isochrysis galbana, Pavlova lutheri, etc. Preferably, the haptophyte is Tisochrysis lutea.

[0024] The diatoms include Chaetoceros, Cyclotella, Fragilaria, Navicula, Amphora, etc. Preferably, the diatom is Chaetoceros neogracile.

[0025] The rotifers may be a plurality of rotifers cultured by different methods. The different methods refer to, for example, different feeds given in the culture, as well as different compositions, temperatures, additives, etc. of the culture water. Preferably, the rotifers include a plurality of rotifers cultured by feeding different feeds. The nutritional value of the compound feed can be controlled by using a plurality of rotifers cultured with feeds enriched with different nutrients. For example, the feed may be a single microalgae different from each other, or may be a first microalgae from the start of the culture and a second microalgae different from the first microalgae after a predetermined period of time, or the first microalgae and the second microalgae different from the first microalgae may be mixed. Preferably, the feed is at least one selected from the group consisting of green algae, haptophytes, and diatoms.

[0026] Here, a method for producing a compound feed according to the present embodiment will be described. The method includes a washing step, a pasting step, a drying step, and a compounding step. In the washing step, the cultured marine rotifers are washed. Preferably, in the washing step, the rotifers are washed with seawater and then with water.

[0027] In the paste-making process, at least a portion of the moisture is removed from the rotifers to obtain a paste. The moisture in the rotifers can be removed by contacting the rotifers with an absorbent that absorbs moisture. For example, the absorbent can be a sponge, paper, fiber, cloth, water-absorbent resin, or the like.

[0028] In the drying step, the paste is dried to obtain a powder (hereinafter also referred to as "rotifer powder"). Any method may be used to dry the paste, but vacuum freeze-drying or lyophilization is preferred. The freeze-drying temperature is, for example, -20 to -10°C, -18 to -12°C, or -16 to -14°C.

[0029] In the blending step, the rotifer powder is blended into the blended feed. The rotifer powder (paste) in the blended feed is preferably 75% by weight or more. The rotifer powder in the blended feed is, for example, 75-95% by weight, 78-95% by weight, 80-95% by weight, 82-95% by weight, 85-95% by weight, 88-95% by weight, or 90-95% by weight. The weight percentage in the blending is dry weight. Ingredients other than the rotifer powder in the blended feed include, for example, vitamins; minerals; fish oil; thickeners; active gluten; n-3 highly unsaturated fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA); α-starch; α-cellulose; choline chloride; and bait attractants such as taurine, histidine, arginine, and inosinic acid. Fish meal may be added to the feed to attract fish-eating fish species, but it is preferable that the amount of fish meal be 5% by weight or less of the mixed feed.

[0030] For example, the compound feed contains each component selected from the ranges shown below such that the total of the weight percentages of each component is 100 weight %. Formulation example 1: Rotifer powder (paste) 75-95% by weight Ingredients other than the above rotifer powder: 5-25% by weight Formulation example 2: Rotifer powder (paste) 75-95% by weight Vitamins 1-3% by weight Fish oil 2~4% by weight Thickener 0-1% by weight Active gluten 0-1% by weight Fishmeal 0~5% by weight At least one selected from minerals, n-3 highly unsaturated fatty acids, α-starch, α-cellulose, choline chloride, and bait attractants (if multiple types are selected, 0 to 11% by weight)

[0031] In the blending step, the rotifer powder and other ingredients may be mixed in a mixer or the like. In the blending step, water may be added in an amount of 20 to 40% of the volume of the mixture and further mixed in order to form the compound feed. After the rotifer powder and other ingredients are thoroughly mixed, the mixture may be formed into any shape, such as a pellet shape. The size of the compound feed is appropriately adjusted according to the size of the mouth of the fish or shellfish to be fed.

[0032] The rotifers washed in the washing step may be multiple rotifers cultured on different feeds. In this case, multiple rotifers cultured on different feeds may be mixed before the washing step, pasting step and drying step, or multiple rotifers cultured on different feeds may each be subjected to the washing step, pasting step and drying step, and then the rotifer powders obtained from multiple rotifers cultured on different feeds may be mixed in the blending step.

[0033] The compound feed according to the present embodiment can be fed to fish and shellfish in any amount, at any timing, and any number of times. Preferably, the compound feed is fed to farmed fish and shellfish.

[0034] As shown in the following examples, the compound feed according to this embodiment is capable of supporting the growth of fish and shellfish sufficiently without the addition of fish meal. The nutritional value of the rotifers can be adjusted by the food given to the rotifers, so nutrients not naturally contained in the rotifers, such as the essential fatty acids DHA and EPA, can be included in the compound feed via the rotifers.

[0035] In addition, the manufacturing method of the compound feed according to this embodiment may include a culture step of culturing the rotifers prior to the washing step.

[0036] The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. EXAMPLES

[0037] Example 1 [Cultivation and paste production of rotifer Brachionus plicatilis] The green algae Chlorella vulgaris (hereinafter referred to as "Chlorella", Raw Chlorella V-12, Chlorella Kogyo Co., Ltd.), the haptophyte Tisochrysis lutea (hereinafter referred to as "Tisochrysis"), the diatom Chaetoceros neogracile (hereinafter referred to as "Chaetoceros"), and the L-type Obama strain of the rotifer Brachionus plicatilis sp.complex were used as the biological feed. The rotifers were cultured in a continuous culture system. 2 / 3 seawater with a temperature of 25°C was used as the culture water. 300 mL (average daily) of Chlorella concentrate was added to the continuous culture system. Three types of rotifers were obtained: (1) Rotifer A cultured only with Chlorella, (2) Rotifer B cultured with Chlorella and then with Tisochrysis for 24 hours, and (3) Rotifer C cultured by mixing equal amounts of Chlorella and Chaetoceros and continuously culturing them. Rotifers A to C were harvested, washed with seawater and then with tap water, and thoroughly removed moisture with dish paper to make a paste. The paste was frozen and stored at -20°C. The cell density of Chlorella was 12 billion cells / mL, that of Tysochrysis was 10.32 million cells / mL, and that of Chaetoceros was 115,000 cells / mL.

[0038] [Preparation of compound feed] The frozen pastes of Rotifers A to C were dried at around -15°C by sublimating the moisture using a vacuum freeze-drying device (VDF-010, ULVAC) and a freeze-drying machine (FDU-1200, Tokyo Rikakikai Co., Ltd.) to produce powder. Rotifer mixtures were prepared by mixing the powders of Rotifers A to C in a volume ratio of Rotifer A: Rotifer B: Rotifer C = 1:1.5:0.5. Next, all the ingredients shown in Table 1 except for fish oil were measured out and mixed for 10 minutes in a commercial mixer (RM-G10A, Remacom Co., Ltd.). Next, fish oil was measured out and added to the mixture, and mixed again for 10 minutes. After that, distilled water was added at about 30% of the volume of the mixture, and mixed for 10 minutes. After mixing, the mixture was passed through a meat chopper (22VR, Alfa Royal Co., Ltd.) twice and formed into pellets. Finally, the molded feed was dried in an oven at 30°C until the moisture content in the feed was approximately 14%, to obtain Feed 1. Feed 2 was prepared in the same manner as Feed 1, using the ingredients shown in Table 2. Carboxymethylcellulose (CMC) was added as a thickener. The vitamin mixture was "Kadai Vitamin" (manufactured by Kokin Chemical Co., Ltd.). The mineral mixture was "Kadai Mineral" (manufactured by Kokin Chemical Co., Ltd.). The activated gluten was "A-Glu SS" (manufactured by Glico Nutrition Foods Co., Ltd.). The effect was the same when commercially available vitamin and mineral mixtures were used.

[0039] [Table 1]

[0040] [Table 2]

[0041] [Rearing red sea bream fry] Ten juvenile red sea bream (Pagrus major) were used as test fish (average fish weight 66.82g). A 500L circular polycarbonate tank was used as the breeding tank, and a closed circulation system was adopted as the water purification method, with physical filtration in a sedimentation tank and nitrification in a biological filtration device. A water storage tank with a heater was installed after the biological filtration tank, and the heater was set to 23.5°C with a thermostat to control the water temperature in all tanks to around 19°C. The breeding period was 29 days, and the number of feedings was three times a day. The feeding amount was set to 3% of the body weight. The pellet size was 4.5 mm. Feed 1 was fed until the 14th day of breeding, and Feed 2 was fed from the 15th day onwards. After feeding, feces, remaining food, etc. were sucked up, and the remaining food that was not ingested was counted.

[0042] [measurement] The body weight of the red sea bream in each test group was measured on the 0th, 14th and 28th days of rearing. The body length of the red sea bream was also measured on the 28th day. When measuring the body length, the red sea bream was anesthetized for several minutes in an anesthesia tank containing seawater containing ethylene glycol monophenyl ether at a concentration of 400 ppm, and the tail fork length was measured with a measuring device. In addition, at the end of the rearing period, the fish was dissected with scissors, and the liver weight was measured with an electronic balance (AX224, SARTORIUS).

[0043] The following indicators were calculated to evaluate growth: Liver weight index (HIS,%) = liver weight (g) × 100 / body weight (g) Obesity index = weight (g) x 1000 / total length (cm) 3 Food intake (g) = (food intake - remaining food) / number of fish Feed conversion efficiency (%) = (body weight at the end of the test - body weight at the start of the test) x 100 / (feed amount - remaining feed amount) Weight gain coefficient = (feed amount - remaining feed amount) / (fish weight at the end of the test - fish weight at the start of the test)

[0044] [result] The average body weight is shown in Figure 1. There was no statistically significant difference between the test and control groups, and growth was equal to or greater with diets 1 and 2 containing rotifers than with diets containing fish meal. Each index is shown in Table 3. The liver weight index was significantly higher in the test group (t-test, n=10, p<0.05).

[0045] [Table 3]

[0046] Example 2 [Preparation of compound feed] Feed 3 was prepared using the rotifer mixture of Example 1 and the materials shown in Table 4. Fish meal and krill were added to Feed 3 for feeding attraction. The feeding attractants included taurine (0.30 wt%), histidine (0.15 wt%), arginine (0.03 wt%) and inosinic acid (0.50 wt%). The fat-soluble vitamins and water-soluble vitamins were prepared by mixing "vitamin A palmitate" (manufactured by Nacalai Tesque) and others and "thiamine hydrochloride" (manufactured by Nacalai Tesque) and others based on the Halver formula.

[0047] [Table 4]

[0048] [Raising yellowtail fry] Ten yellowtail (Seriolla quinqueradiata) juveniles were used as test fish (average fish weight 117.67g). A 500L circular polycarbonate tank was used as the rearing tank, and a flow-through system was used for water purification, with the water temperature in all tanks kept at natural temperature. The rearing period was 20 days, with feeding twice a day. The amount of food given was set at 3% of body weight. The pellet size was 4.5mm. After feeding Feed 3, feces, remaining food, etc. were sucked up, and the amount of remaining food that was not ingested was counted.

[0049] [measurement] The body weights of the yellowtails in each test group were measured on days 0, 13, and 20 of rearing. On day 20, the body lengths of the yellowtails were also measured in the same manner as in Example 1. At the end of the rearing period, the fish were dissected using scissors, and the liver weights were measured in the same manner as in Example 1. In addition to the above-mentioned weight gain coefficient, feed intake, and feed conversion efficiency, the following weight gain rate was calculated as an index for evaluating growth. Weight gain rate (%) = (fish weight at the end of the test - fish weight at the start of the test) x 100 / fish weight at the start of the test

[0050] [result] The average body weight is shown in Figure 2. There was no statistically significant difference between the test and control groups, and the rotifer-based diet 3 produced growth equal to or greater than that of the diet containing fish meal as the main ingredient. The various indices are shown in Table 5. There was no statistically significant difference in any of the indices. The survival rate in the test group was 100%, while that in the control group was 50%.

[0051] [Table 5]

[0052] The present invention allows various embodiments and modifications without departing from the broad spirit and scope of the present invention. The above-described embodiments are for the purpose of explaining the present invention and do not limit the scope of the present invention. That is, the scope of the present invention is indicated by the claims, not the embodiments. Various modifications made within the scope of the claims and the scope of the invention equivalent thereto are considered to be within the scope of the present invention. [Industrial Applicability]

[0053] The present invention is suitable for fish and shellfish farming.

Claims

1. Contains marine rotifer paste, Mixed feed for fish and shellfish.

2. The paste is 75% by weight or more. The fish and shellfish feed according to claim 1.

3. For young fish, The fish and shellfish feed according to claim 1 or 2.

4. a washing step of washing the cultured marine rotifers; A pasting step of removing at least a portion of the water from the marine rotifers to obtain a paste; a drying step of drying the paste to obtain a powder; A blending step of blending the powder into a fish and shellfish feed; A method for producing a compound feed for fish and shellfish, comprising:

5. The marine rotifers washed in the washing step include The study included multiple marine rotifers cultured on different diets. A method for producing the fish and shellfish feed according to claim 4.

6. The bait is At least one selected from the group consisting of green algae, haptophytes and diatoms; A method for producing the fish and shellfish feed according to claim 5.

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