Mandarin fish taming feed composition based on earthworm raw material

Abstract

The invention discloses a mandarin fish taming feed composition based on earthworm raw materials, and belongs to the technical field of aquatic feed. The mandarin fish taming feed composition comprises the following components in percentage by weight: 50%-65% of earthworm ferment powder, 10%-25% of white fish meal, 10%-20% of pregelatinized starch, 5%-10% of krill meal, 1%-2% of a phagostimulant and 1%-1.5% of a compound vitamin premix, wherein the earthworm fermentation powder is added in a form of an embedding body formed by embedding, the inner core of the embedding body is earthworm fermentation liquor, the middle layer is a chitosan-sodium alginate film, the outer layer is liposome, and the phagostimulant is a mixture of the earthworm fermentation liquor and ethyl maltol. In the feed, the earthworms are added in the form of earthworm ferment powder, the use amount of the earthworms can be increased, and the earthworm ferment powder is added in the form of an embedding body formed by embedding, so that the release of earthworm fermentation components is controlled, and the utilization rate of the feed is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of aquaculture, in particular to the technical field of artificial aquaculture feed, and specifically relates to a feed composition for mandarin fish acclimated based on earthworm raw materials. Background Art

[0002] The meat of mandarin fish is tender and nutritious. It contains a large amount of protein and trace elements, vitamins, lecithin, etc. needed by the human body. It can enhance memory, thinking and analytical abilities, delay brain decline, warm the middle and replenish qi, warm the stomach, moisturize the skin, etc. It is a warming and qi-replenishing health food, and is also the main source of protein food for the Chinese people.

[0003] Mandarin fish are typically carnivorous and predatory, feeding on the fry of other fish immediately after hatching. Consequently, traditional mandarin fish farming primarily relies on live fish as bait. However, the current high price of live fish bait has increased the cost of live fish farming, resulting in low economic returns. Furthermore, using live fish as bait is difficult to manage and can lead to the horizontal spread of bacteria and viruses, increasing aquaculture risks.

[0004] Therefore, research on pelleted feeds for mandarin fish is currently receiving considerable attention. For example, Chinese patent application CN118985788A discloses a functional mandarin fish feed and its preparation method, comprising the following components by weight: 440-450 parts fish meal, 185-195 parts krill meal, 55-65 parts American cockroach meal, 25-35 parts intestinal membrane protein powder, 35-45 parts dehulled soybean meal, 55-65 parts fermented soybean meal, 90-110 parts starch, 30 parts multivitamin and multimineral premix, and 0.3-0.5 parts of American cockroach extract mixed in the multivitamin and multimineral premix. By adding medicinal insect raw materials and insect extracts with immune-enhancing effects to the feed formula, the immunity of mandarin fish is improved, thereby achieving the goals of efficient breeding, efficient feed utilization, and rapid growth.

[0005] Another example is a low-cost 50-150g artificial feed for mandarin fish disclosed in CN105394447A, the raw materials of which include, by weight: 50-100g of fish meal, 80-150g of shrimp meal, 50-80g of clams, 1-7g of cod liver oil, 2-8g of palm oil, 5-10g of citrus oil, 5-15g of shell powder, 15-30g of sweet corn protein powder, 5-12g of sea cucumber, 5-12g of snail, 15-30g of fermented biological protein, 8-18g of earthworm, 2-5g of bloodworm, 2-5g of aloe powder, 1-2g of lotus leaf powder, 0.2-0.85g of sodium inosinate, 0.2-0.8g of methionine, 0.2-0.85g of threonine, 0.001-0.0085g of complex enzyme, 0.015-0.24g of trace elements, 2-6g of Chinese herbal medicine, 5-10g of attractant, and 0.55-1.55g of complex vitamin. It is used for 6-15cm mandarin fish. Even in the case of artificial high-density breeding, the mortality rate is extremely low, and it can reduce the stress of changing feeds, facilitate the transition of changing feeds, and the feed has good palatability, high nutritional value, reasonable ratio, low cost and delicious meat.

[0006] However, through actual use, it was found that these artificial pellet feeds still have defects such as slow opening and unstable feeding conditions compared to live fish bait. Summary of the Invention

[0007] The purpose of the present invention is to provide a feed composition for mandarin fish acclimation based on earthworm raw materials. The composition takes earthworms as one of the main raw materials, fully utilizes the advantages of the raw earthworms, can greatly improve the feed opening ability of mandarin fish, and has a high feed utilization rate.

[0008] The present invention provides a feed composition for mandarin fish taming based on earthworm raw materials, which adopts the following technical solutions:

[0009] A feed composition for mandarin fish training based on earthworm raw materials comprises the following components: 50% to 65% of earthworm fermentation powder, 10% to 25% of white fish meal, 10% to 20% of pregelatinized starch, 5% to 10% of krill meal, 1% to 2% of an attractant, and 1% to 1.5% of a multivitamin premix; wherein the earthworm fermentation powder is added in the form of an embedded body, the inner core of the embedded body is earthworm fermentation liquid, the middle layer is a chitosan-sodium alginate membrane, and the outer layer is a liposome; and the attractant is a mixture of earthworm fermentation liquid and ethyl maltol.

[0010] Earthworms are a premium ingredient in fish feed and a source of high-quality protein. Their dry matter contains 60%-70% crude protein, a level far higher than many common plant-based feeds and even higher than some fish meal. Furthermore, earthworms' body walls are primarily composed of muscle, lacking a chitinous shell, making them highly digestible and absorbable by fish, resulting in a high feed conversion rate. Earthworms secrete unique odorants (both in their body fluids and on their surface mucus) that have a strong natural appeal to most carnivorous, omnivorous, and even some herbivorous fish. They can stimulate fish's appetite and significantly increase their feed intake, making them particularly suitable for fish with poor appetite or for training fry to consume artificial feeds.

[0011] However, earthworms currently have limitations when used in fish feed. One limitation is that earthworms contain gamma-formic acid, which has an anesthetic effect. Excessive feeding can cause gastrointestinal paralysis and affect appetite. Therefore, the proportion of earthworm powder added to rabbit feed should not be too high, which limits the widespread use of earthworms as fish feed.

[0012] In the above scheme of the present invention, it is found that the addition of earthworms in the form of earthworm fermentation powder can increase its usage. In this scheme, it can be increased to 50% to 65%, which is the highest content among the components.

[0013] However, in the early stages of research and development, when earthworm fermentation powder was directly added, it was found that the utilization rate of the feed was not high, and was even lower than the feed utilization rate of earthworms added at a low content. The inventors speculated that this may be because: 1. The mandarin fish has poor appetite for this feed, and 2. The earthworm fermentation powder easily disintegrates in water, resulting in the loss of nutrients and a decrease in utilization rate.

[0014] To address this problem, this solution is proposed from three aspects. First, a specific attractant is added, which has a strong attractant effect on mandarin fish in feed with earthworms as the main ingredient; second, earthworm fermentation powder is added in the form of an embedded body to control the release of earthworm fermentation components, thereby improving feed utilization; 3. By adding pregelatinized starch to the components, the pregelatinized starch can swell in water at room temperature (gelatinization degree ≥ 85%) to form a three-dimensional gel network, which wraps the feed particles into a stable structure, and the stability of the particles in water is improved. At the same time, the pregelatinized starch can be partially fermented by mandarin fish intestinal microorganisms to provide energy. The pregelatinized starch can also delay the dissolution of earthworm enzymatic hydrolysates / attractants, and assist in the step-by-step release in the intestine.

[0015] In summary, in this solution, by optimizing the composition and addition method, the amount of earthworms added is greatly increased, while the feed opening rate and utilization rate are improved.

[0016] Preferably, the embedded body is obtained by the following method:

[0017] S1. Core construction: Earthworm fermentation broth was mixed with trehalose-mannitol cryoprotectant and spray-dried (inlet air temperature ≤ 45°C) to obtain primary microparticles.

[0018] S2. Middle layer coating: The primary particles are placed in a fluidized bed, sprayed with a film-forming liquid formed by chitosan and sodium alginate, and the particle temperature is controlled to be ≤35°C to obtain middle layer particles;

[0019] S3. Outer layer coating: The liposomes are mixed with the middle layer particles and coated under the action of a high-voltage electrostatic generator to obtain embedded particles;

[0020] S4. Place the embedded particles in a supercritical reactor, introduce liquid CO2, maintain the supercritical state for 30 minutes, and release the pressure at a rate of 0.5 MPa / min to obtain the embedded body.

[0021] The preparation method of the above-mentioned embedded body achieves near-zero loss of effective ingredients of earthworm fermentation products through the technical route of low-temperature active protection-gradient film formation-supercritical solidification. After the outer layer is coated, it is treated under supercritical CO2 conditions to form stable microcapsules, so that the release of the inner core components of the embedded body can be controlled.

[0022] Preferably, the earthworm fermentation liquid is obtained by the following method:

[0023] Step a: soaking live earthworms in green tea soaking liquid for a period of time to obtain earthworm soaking liquid;

[0024] Step b: adding lactic acid bacteria to the earthworm bath solution and fermenting for 72 hours;

[0025] Step c: After the fermentation product is homogenized and broken by high pressure (50 MPa), 0.1% lipase is added and enzymatically hydrolyzed for 2 h to obtain earthworm fermentation liquid.

[0026] Preferably, the liposome is a mixture of krill oil, lecithin and cholesterol in a ratio of 7:2:1.

[0027] In the above scheme of the present invention, live earthworms are prepared into earthworm fermentation powder by a specific method. First, the live earthworms are bathed in green tea soaking liquid. This step stimulates the earthworms with the green tea soaking liquid to secrete more surface mucus and mucopolysaccharides and other components. The earthworms are then fermented with yeast, and then homogenized and crushed, and finally freeze-dried to obtain the earthworm fermentation powder.

[0028] After experiments, it was found that the earthworm fermentation powder processed by the above specific method has better feeding properties and significantly improved weight growth rate. Based on this, the contact time of live earthworms with green tea soaking solution and the concentration of the soaking solution are crucial to the results. If the contact time of live earthworms with green tea soaking solution is too short, the pathway is not fully activated, and if the contact time is too long, the earthworms will be exhausted. If the concentration of the soaking solution is too low, the stress is insufficient, and if it is too high, the earthworm mortality rate will rise sharply. Through optimization, in step a, the soaking time of live earthworms in green tea soaking solution is 8-12 hours, and the concentration of green tea and water is 60g-150g / 1L.

[0029] Preferably, in step b, the fermentation temperature is 35°C ± 2°C and the pH is 5.8-6.2.

[0030] Preferably, in step a, the ratio of live earthworms to green tea soaking liquid is 1:1.

[0031] Preferably, the live earthworms are starved before step a, and the starvation treatment time is at least 24 hours, preferably 24-26 hours.

[0032] Preferably, the green tea infusion is prepared as follows: immerse the green tea in water at a ratio of 60g-150g / 1L, control the temperature at 40°C ± 5°C, and the pressure at 1.8MPa-2.5MPa, overnight with low-speed stirring, for example, at 80-100rpm.

[0033] The beneficial effects of the present invention are:

[0034] The present invention adds earthworms to the feed in the form of earthworm fermentation powder, which can increase their usage. In this solution, the usage can be increased to 50% to 65%, which is the highest content among the components. The earthworm fermentation powder is added in the form of an embedded body to control the release of earthworm fermentation components and improve feed utilization. At the same time, the present invention adds a specific attractant to the feed. The attractant has a strong attractant effect on mandarin fish in the feed with earthworms as the main raw material, and pregelatinized starch is added to the component. The three-dimensional gel network formed by the pregelatinized starch in normal temperature water is used to wrap the feed particles into a stable structure, thereby improving the stability of the particles in water and further improving the utilization rate of the feed. DETAILED DESCRIPTION

[0035] The technical solutions of the present invention are described clearly and completely below with the aid of embodiments. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are also within the scope of protection of the present invention.

[0036] Example 1

[0037] A feed composition for taming mandarin fish based on earthworm raw materials comprises the following components: 60% earthworm fermentation powder, 15% white fish meal, 15% pregelatinized starch, 7% krill meal, 2% attractant, and 1% multivitamin premix.

[0038] The earthworm fermentation liquid is obtained by the following method:

[0039] The live earthworms were beaten into pulp and Lactobacillus plantarum (CGMCC.5297) culture was added. The inoculation amount of lactic acid bacteria was 8% (the number of live bacteria was ≥10 9 CFU / mL) and fermented under anaerobic conditions for 72 hours. The fermentation temperature was controlled at 35°C and the pH was maintained at 6.0.

[0040] The fermentation product was subjected to high-pressure homogenization and wall-breaking treatment at a pressure of 50 MPa, and then 0.1% lipase was added and enzymatically hydrolyzed at 37° C. for 2 hours to obtain earthworm fermentation liquid.

[0041] The earthworm fermentation powder is added in the form of an embedding body, and the method for preparing the embedding body is as follows:

[0042] S1. Mix earthworm fermentation liquid with trehalose-mannitol cryoprotectant (mass ratio 1:1) and spray dry (inlet air temperature 40°C) to obtain primary microparticles.

[0043] S2. The primary particles are placed in a fluidized bed, sprayed with a film-forming liquid (atomizing pressure 0.3 MPa), and the particle temperature is controlled to be ≤35°C to obtain middle-layer particles;

[0044] Membrane-forming solution: chitosan (deacetylation degree ≥ 95%): sodium alginate = 3:1 (w / w) dissolved in 0.5% acetic acid solution, add 0.1% CaCl2 as a cross-linking enhancer, and stir thoroughly.

[0045] S3. Liposomes and middle-layer microparticles were mixed at a ratio of 1:10 and directional coating was achieved under the action of a high-voltage electrostatic generator (15 kV);

[0046] Liposome: krill oil: lecithin: cholesterol = 7:2:1.

[0047] S4. Place the embedded particles in a supercritical reactor, introduce liquid CO2 to a pressure of 15 MPa and a temperature of 40°C, and maintain for 30 minutes; then release the pressure at a rate of 0.5 MPa / min to obtain an embedded body.

[0048] The multivitamin premix comprises 560 IU / kg of vitamin A, 5 mg / kg of vitamin B12, 4 mg / kg of vitamin C, 1000 IU / kg of vitamin D, 850 mg / kg of vitamin K, 8600 mg / kg of thiamine B1, 9300 mg / kg of riboflavin B2, 28000 mg / kg of pantothenic acid B3, 51000 mg / kg of niacin, 4000 mg / kg of pyridoxine B6 and 80 mg / kg of biotin.

[0049] The attractant includes earthworm fermentation liquid and ethyl maltol, which are mixed in a volume-mass ratio of 1:1.

[0050] Example 2

[0051] The only difference from Example 1 is that the preparation method of the earthworm fermentation liquid is different. In this embodiment, the earthworm fermentation liquid is obtained by the following method:

[0052] Before being immersed in the green tea solution, the live earthworms are starved for 24 hours. This starvation treatment involves placing the live earthworms in clean water without any food, allowing them to empty their intestinal contents and reduce impurities in subsequent processing.

[0053] The green tea infusion was prepared as follows: the green tea was immersed in water at a ratio of 80 g / 1 L, the temperature was controlled at 40° C., the pressure was controlled at 2.0 MPa, and the infusion was stirred at a low speed of 90 rpm overnight.

[0054] Step a: Starved live earthworms are mixed with green tea soaking solution at a ratio of 1:2 and soaked for 10 hours to obtain an earthworm soaking solution. During the soaking process, the active ingredients in the green tea soaking solution can fully contact the surface and internal substances of the earthworms, promoting the release of beneficial ingredients.

[0055] Step b: Add Lactobacillus plantarum (CGMCC.5297) to the earthworm bath solution, with the inoculation amount of lactic acid bacteria being 8% (viable bacteria count ≥ 10 9 CFU / mL) and fermented under anaerobic conditions for 72 hours. The fermentation temperature was controlled at 35°C and the pH was maintained at 6.0.

[0056] Step c: The fermentation product was subjected to high-pressure homogenization and wall-breaking treatment at a pressure of 50 MPa, and then 0.1% lipase was added and enzymatically hydrolyzed at 37° C. for 2 hours to obtain earthworm fermentation liquid.

[0057] Example 3

[0058] A feed composition for taming mandarin fish based on earthworm raw materials comprises the following components: 50% earthworm fermentation powder, 25% white fish meal, 15% pregelatinized starch, 8% krill meal, 1% attractant, and 1% multivitamin premix.

[0059] The earthworm fermentation liquid is obtained by the following method:

[0060] Before being immersed in the green tea solution, the live earthworms are starved for 24 hours. This starvation treatment involves placing the live earthworms in clean water without any food, allowing them to empty their intestinal contents and reduce impurities in subsequent processing.

[0061] The green tea infusion was prepared as follows: the green tea was immersed in water at a ratio of 80 g / 1 L, the temperature was controlled at 40° C., the pressure was controlled at 2.0 MPa, and the infusion was stirred at a low speed of 90 rpm overnight.

[0062] Step a: Starved live earthworms are mixed with green tea soaking solution at a ratio of 1:2 and soaked for 10 hours to obtain an earthworm soaking solution. During the soaking process, the active ingredients in the green tea soaking solution can fully contact the surface and internal substances of the earthworms, promoting the release of beneficial ingredients.

[0063] Step b: Add Lactobacillus plantarum (CGMCC.5297) to the earthworm bath solution, with the inoculation amount of lactic acid bacteria being 8% (viable bacteria count ≥ 10 9 CFU / mL) and fermented under anaerobic conditions for 72 hours. The fermentation temperature was controlled at 35°C and the pH was maintained at 6.0.

[0064] Step c: The fermentation product was subjected to high-pressure homogenization and wall-breaking treatment at a pressure of 50 MPa, and then 0.1% lipase was added and enzymatically hydrolyzed at 37° C. for 2 hours to obtain earthworm fermentation liquid.

[0065] The earthworm fermentation powder is added in the form of an embedding body, and the method for preparing the embedding body is as follows:

[0066] S1. Mix earthworm fermentation liquid with trehalose-mannitol cryoprotectant (mass ratio 1:1) and spray dry (inlet air temperature 40°C) to obtain primary microparticles.

[0067] S2. The primary particles are placed in a fluidized bed, sprayed with a film-forming liquid (atomizing pressure 0.3 MPa), and the particle temperature is controlled to be ≤35°C to obtain middle-layer particles;

[0068] Membrane-forming solution: chitosan (deacetylation degree ≥ 95%): sodium alginate = 3:1 (w / w) dissolved in 0.5% acetic acid solution, add 0.1% CaCl2 as a cross-linking enhancer, and stir thoroughly.

[0069] S3. Liposomes and middle-layer microparticles were mixed at a ratio of 1:10 and directional coating was achieved under the action of a high-voltage electrostatic generator (15 kV);

[0070] Liposome: krill oil: lecithin: cholesterol = 7:2:1.

[0071] S4. Place the embedded particles in a supercritical reactor, introduce liquid CO2 to a pressure of 15 MPa and a temperature of 40°C, and maintain for 30 minutes; then release the pressure at a rate of 0.5 MPa / min to obtain an embedded body.

[0072] The multivitamin premix comprises 560 IU / kg of vitamin A, 5 mg / kg of vitamin B12, 4 mg / kg of vitamin C, 1000 IU / kg of vitamin D, 850 mg / kg of vitamin K, 8600 mg / kg of thiamine B1, 9300 mg / kg of riboflavin B2, 28000 mg / kg of pantothenic acid B3, 51000 mg / kg of niacin, 4000 mg / kg of pyridoxine B6 and 80 mg / kg of biotin.

[0073] The attractant includes earthworm fermentation liquid and ethyl maltol, which are mixed in a volume-mass ratio of 1:1.

[0074] Example 4

[0075] A mandarin fish training feed composition based on earthworm raw materials comprises the following components: 65% earthworm fermentation powder, 15% white fish meal, 12% pregelatinized starch, 5% krill meal, 2% attractant, and 1% multivitamin premix.

[0076] The earthworm fermentation liquid is obtained by the following method:

[0077] Before being immersed in the green tea solution, the live earthworms are starved for 24 hours. This starvation treatment involves placing the live earthworms in clean water without any food, allowing them to empty their intestinal contents and reduce impurities in subsequent processing.

[0078] The green tea infusion was prepared as follows: the green tea was immersed in water at a ratio of 80 g / 1 L, the temperature was controlled at 40° C., the pressure was controlled at 2.0 MPa, and the infusion was stirred at a low speed of 90 rpm overnight.

[0079] Step a: Starved live earthworms are mixed with green tea soaking solution at a ratio of 1:2 and soaked for 10 hours to obtain an earthworm soaking solution. During the soaking process, the active ingredients in the green tea soaking solution can fully contact the surface and internal substances of the earthworms, promoting the release of beneficial ingredients.

[0080] Step b: Add Lactobacillus plantarum (CGMCC.5297) to the earthworm bath solution, with the inoculation amount of lactic acid bacteria being 8% (viable bacteria count ≥ 10 9 CFU / mL) and fermented under anaerobic conditions for 72 hours. The fermentation temperature was controlled at 35°C and the pH was maintained at 6.0.

[0081] Step c: The fermentation product was subjected to high-pressure homogenization and wall-breaking treatment at a pressure of 50 MPa, and then 0.1% lipase was added and enzymatically hydrolyzed at 37° C. for 2 hours to obtain earthworm fermentation liquid.

[0082] The earthworm fermentation powder is added in the form of an embedding body, and the method for preparing the embedding body is as follows:

[0083] S1. Mix earthworm fermentation liquid with trehalose-mannitol cryoprotectant (mass ratio 1:1) and spray dry (inlet air temperature 40°C) to obtain primary microparticles.

[0084] S2. The primary particles are placed in a fluidized bed, sprayed with a film-forming liquid (atomizing pressure 0.3 MPa), and the particle temperature is controlled to be ≤35°C to obtain middle-layer particles;

[0085] Membrane-forming solution: chitosan (deacetylation degree ≥ 95%): sodium alginate = 3:1 (w / w) dissolved in 0.5% acetic acid solution, add 0.1% CaCl2 as a cross-linking enhancer, and stir thoroughly.

[0086] S3. Liposomes and middle-layer microparticles were mixed at a ratio of 1:10 and directional coating was achieved under the action of a high-voltage electrostatic generator (15 kV);

[0087] Liposome: krill oil: lecithin: cholesterol = 7:2:1.

[0088] S4. Place the embedded particles in a supercritical reactor, introduce liquid CO2 to a pressure of 15 MPa and a temperature of 40°C, and maintain for 30 minutes; then release the pressure at a rate of 0.5 MPa / min to obtain an embedded body.

[0089] The multivitamin premix comprises 560 IU / kg of vitamin A, 5 mg / kg of vitamin B12, 4 mg / kg of vitamin C, 1000 IU / kg of vitamin D, 850 mg / kg of vitamin K, 8600 mg / kg of thiamine B1, 9300 mg / kg of riboflavin B2, 28000 mg / kg of pantothenic acid B3, 51000 mg / kg of niacin, 4000 mg / kg of pyridoxine B6 and 80 mg / kg of biotin.

[0090] The attractant includes earthworm fermentation liquid and ethyl maltol, which are mixed in a volume-mass ratio of 1:1.

[0091] Comparative Example 1

[0092] A feed composition for mandarin fish training is provided, which differs from Example 1 in that earthworm powder is used in this comparative example instead of the earthworm fermentation liquid in Example 1. The earthworm powder is prepared by drying live earthworms and grinding them into powder.

[0093] Comparative Example 2

[0094] A feed composition for taming mandarin fish is provided, which differs from the one in that earthworm powder is used in place of the earthworm fermentation liquid in the one example.

[0095] The preparation method of earthworm powder is as follows: beat the live earthworms into pulp, freeze-dry and grind them.

[0096] Healthy mandarin fish juveniles (initial weight 5.0±0.2 g) were cultured in groups of 3 replicates, with 100 juveniles per replicate. The culture system was a circulating water system (water temperature 25±1° C., dissolved oxygen >6 mg / L). The compound feeds of the embodiments and comparative examples were fed at a feeding rate of 3% body weight / day, three times a day (8:00 / 12:00 / 17:00), for a 30-day culture period.

[0097] Measurement indicators:

[0098] Opening survival rate:

[0099] On the 7th day, the number of surviving fish was counted: the survival rate after opening (%) = the number of surviving fish / the initial number of fish × 100%.

[0100] Feed utilization:

[0101] On day 30, feed utilization (%) was calculated as total weight gain / total dry weight of feed intake.

[0102] Experimental results:

[0103] Table 1 Experimental results of opening survival rate and feed utilization rate

[0104] Group Opening survival rate (%) Feed utilization rate (%) Example 1 85 56.1 Example 2 95 67.3 Example 3 96 64.8 Example 4 96 65.5 Comparative Example 1 66 34.9 Comparative Example 2 70 37.2

[0105] The results shown in Table 1 indicate that, when the feed compositions of the present invention were used in Examples 1 to 4 and fed to juvenile mandarin fish for 30 days, the survival rate of juvenile mandarin fish reached over 85%, significantly higher than that of Comparative Examples 1 and 2. In particular, Examples 2 to 4 employed green tea infusion during the earthworm fermentation stage, which had a positive effect on the survival rate, increasing it to over 95%. Compared to feed utilization, the trends were essentially the same.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A feed composition for mandarin fish based on earthworm raw materials, characterized in that: The invention comprises the following components in weight percentage: 50% to 65% of earthworm fermentation powder, 10% to 25% of white fish meal, 10% to 20% of pregelatinized starch, 5% to 10% of krill meal, 1% to 2% of attractant, and 1% to 1.5% of multivitamin premix; wherein the earthworm fermentation powder is added in the form of an embedded body, the inner core of the embedded body is earthworm fermentation liquid, the middle layer is a chitosan-sodium alginate membrane, and the outer layer is a liposome; the attractant is a mixture of earthworm fermentation liquid and ethyl maltol.

2. The feed composition for taming mandarin fish according to claim 1, characterized in that The embedded body is obtained by the following method: S1. Core construction: Earthworm fermentation broth was mixed with trehalose-mannitol cryoprotectant and spray-dried to obtain primary microparticles. S2. Middle layer coating: The primary particles are placed in a fluidized bed, sprayed with a film-forming liquid formed by chitosan and sodium alginate, and the particle temperature is controlled to be ≤35°C to obtain middle layer particles; S3. Outer layer coating: The liposomes are mixed with the middle layer particles and coated under the action of a high-voltage electrostatic generator to obtain embedded particles; S4. Place the embedded particles in a supercritical reactor, introduce liquid CO2, maintain the supercritical state for 30 minutes, release the pressure, and obtain the embedded body.

3. The feed composition for taming mandarin fish according to claim 2, characterized in that: The earthworm fermentation liquid is obtained by the following method: Step a: soaking live earthworms in green tea soaking liquid for a period of time to obtain earthworm soaking liquid; Step b: adding lactic acid bacteria to the earthworm bath solution for anaerobic fermentation; Step c: After the fermentation product is homogenized and broken by high pressure, lipase is added for enzymolysis to obtain earthworm fermentation liquid.

4. The feed composition for taming mandarin fish according to claim 2, characterized in that: The liposome is a mixture of krill oil, lecithin and cholesterol.

5. The feed composition for taming mandarin fish according to claim 3, characterized in that: In step a, the living earthworms are immersed in the green tea soaking liquid for 8-12 hours, and the ratio of green tea to water is 60g-150g / 1L.

6. The feed composition for taming mandarin fish according to claim 3, characterized in that: In step b, the fermentation temperature is 35°C ± 2°C and the pH is 5.8-6.

2.

7. The feed composition for acclimating mandarin fish according to claim 3, characterized in that: In step a, the ratio of adding live earthworms to green tea soaking liquid is 1:

1.

8. The feed composition for acclimating mandarin fish according to claim 3, characterized in that: Before step a, the live earthworms are starved for at least 24 hours, preferably 24-26 hours.

9. The feed composition for acclimating mandarin fish according to claim 8, characterized in that: The green tea soaking liquid is prepared as follows: green tea and water are mixed in a ratio of 60g-150g / 1L, the green tea is immersed in water, the temperature is controlled at 40°C±5°C, the pressure is controlled at 1.8MPa-2.5MPa, and the solution is treated overnight with low-speed stirring.