Feed additive for holothurian culture and preparation method thereof

Abstract

The invention discloses a holothurian culture feed additive and a preparation method thereof, and belongs to the technical field of aquaculture. According to the technical scheme, the holothurian culture feed additive comprises the following components in percentage by mass: 45%-55% of fish meal, 2%-3% of butyric acid bacteria, 25%-30% of compound probiotics, 2%-4% of a Chinese herbal medicine extract, 8%-12% of a fermentation substrate, 10%-15% of seaweed meal, 0.5%-1% of vitamin E, 0.5%-1% of selenium yeast and the balance of a carrier, the compound probiotics are composed of lactic acid bacteria, bacillus and photosynthetic bacteria according to the mass ratio of 2: 1: 1; the Chinese herbal medicine extract is a mixture of astragalus polysaccharide and an asarum extract in a mass ratio of 3: 1; through the synergistic effect of the fish meal, the compound probiotics, the Chinese herbal medicine extract and other components, nutrition balance and intestinal flora regulation and control are achieved, the problems of slow growth, intestinal diseases and water quality pollution caused by traditional feed are effectively solved, and the sea cucumber feed has the advantages that the survival rate of sea cucumbers is increased, and the culture benefits are increased.

Description

Technical Field

[0001] This invention belongs to the field of aquaculture technology, specifically relating to a sea cucumber aquaculture feed additive and its preparation method. Background Technology

[0002] Sea cucumbers, as a high-value aquatic species, have seen rapid expansion in aquaculture in recent years. However, traditional sea cucumber farming relies on natural feed or single-formula feed, which presents the following problems: nutritional imbalance, as traditional feeds are mainly composed of fishmeal and soybean meal, lacking essential amino acids and unsaturated fatty acids, resulting in slow growth and poor disease resistance in sea cucumbers; potential intestinal health risks, as sea cucumbers have short intestines and weak digestive capacity, and high-protein feeds can easily lead to intestinal flora imbalance, inducing diseases such as skin rot syndrome and scab formation, resulting in high mortality rates; and severe water pollution, as unused proteins in uneaten feed and feces decompose to produce ammonia nitrogen and nitrite, leading to water deterioration and increasing farming costs due to frequent water changes. While existing technologies, such as traditional feed additives, can improve growth rate, they fail to address the synergistic effect of traditional Chinese medicine and microorganisms. Furthermore, they use a limited variety of probiotics and lack specificity for water quality restoration. The combined use of microorganisms and traditional Chinese medicine, while possessing antibacterial effects, does not address the regulation of short-chain fatty acids in the gut by butyric acid bacteria and does not cover the specific nutritional needs of sea cucumbers during their reproductive period. Water quality control technologies, while capable of degrading ammonia nitrogen, lack synergistic design with feed additives, failing to achieve dual "in vivo-in vitro" regulation through sea cucumber feeding behavior. The technological bottlenecks lie in balancing the nutritional and functional properties of feed to simultaneously meet the needs of growth, immunity, and reproduction; overcoming the limitations of single-component effects through the synergistic effects of microorganisms, traditional Chinese medicine, and enzyme preparations; and achieving long-term, stable water quality regulation through feed additives, reducing the frequency of water changes. Sea cucumber farmers urgently need a highly efficient, environmentally friendly, and multifunctional compound feed additive to improve survival rates and farming efficiency. Existing technologies urgently need improvement to address these issues. Summary of the Invention

[0003] This invention provides a sea cucumber aquaculture feed additive and its preparation method to solve at least one of the above-mentioned technical problems.

[0004] The technical solution adopted in this invention is as follows:

[0005] A sea cucumber aquaculture feed additive comprises the following components in weight percentage: 45%-55% fish meal, 2%-3% butyric acid bacteria, 25%-30% compound probiotics, 2%-4% traditional Chinese medicine extract, 8%-12% fermentation substrate, 10%-15% seaweed powder, 0.5%-1% vitamin E, 0.5%-1% selenium yeast, with the remainder being a carrier; the compound probiotics are composed of lactic acid bacteria, Bacillus, and photosynthetic bacteria in a weight ratio of 2:1:1; the traditional Chinese medicine extract is a mixture of astragalus polysaccharide and asarum extract in a weight ratio of 3:1.

[0006] Furthermore, this application also proposes that the butyric acid bacteria is Clostridium butyricum, with a viable count ≥1×10⁻⁶. 9 CFU / g, added at 2%-3% of the total mass; the fermentation substrate is a liquid substrate of fish slurry and shrimp slurry mixed at a mass ratio of 2:1, with an acid-soluble protein content ≥30%; the seaweed powder is selected from at least one of kelp powder and Sargassum powder, with an iodine content ≥200 mg / kg and a cellulose content ≤15%.

[0007] Furthermore, this application also proposes that the lactic acid bacteria are a mixture of Lactobacillus plantarum and Lactobacillus acidophilus; the Bacillus is Bacillus subtilis; and the photosynthetic bacteria is Rhodopseudomonas palustris.

[0008] Furthermore, this application also proposes that the mass ratio of vitamin E to selenium yeast is 1:1, and the total addition amount is 1%-2%.

[0009] Furthermore, this application also proposes that the carrier is a mixture of microcrystalline cellulose and diatomaceous earth with a particle size of 80-120 mesh and an oil absorption rate of ≥150%.

[0010] Furthermore, this application also proposes that it further includes a complex enzyme preparation comprising 0.5%-1% of the total amount, the complex enzyme preparation being composed of neutral protease, xylanase and alginate lyase in an activity unit ratio of 3:2:1.

[0011] Furthermore, this application also proposes that the lactic acid bacteria in the compound probiotics are a mixture of Lactobacillus plantarum and Bifidobacterium bifidum, and the mass ratio of the two is 3:1.

[0012] Furthermore, this application also proposes that the carrier is porous diatomaceous earth particles loaded with nano-titanium dioxide, with a particle size of 50-100μm and a specific surface area ≥200m2 / g, and the nano-titanium dioxide loading is 0.5%-1% of the carrier mass; when used in a low-temperature aquaculture environment (water temperature ≤10℃), an additional 1%-2% of Antarctic krill powder is added, and the compound probiotics are replaced with cold-resistant strains, with a mass ratio of 2:1.

[0013] A method for preparing a sea cucumber aquaculture feed additive includes the following steps: Step 1: Mix fish slurry and shrimp slurry, adjust the pH to 6.0-6.5, add lactic acid bacteria and butyric acid bacteria, and ferment at 30-35℃ for 48-72 hours to obtain a fermentation substrate; Step 2: Mix and pulverize fish meal, seaweed powder, traditional Chinese medicine extract, and carrier to 80-100 mesh; Step 3: Mix the fermentation substrate from Step 1 with the mixture from Step 2, compound probiotics, vitamin E, and selenium yeast, and granulate the mixture to a particle diameter of 1-2 mm.

[0014] Preferably, during the fermentation process in step one, zinc sulfate and ferrous sulfate are added in addition to 0.1%-0.3% of the fermentation substrate mass, and the fermentation temperature is controlled in two stages: 30-32℃ for the first 24 hours to promote the proliferation of lactic acid bacteria; and 35-37℃ for the next 24-48 hours to activate Clostridium butyricum to produce acid.

[0015] Due to the adoption of the above technical solution, the beneficial effects achieved by this invention are as follows:

[0016] 1. This solution combines a complex of microbial flora with extracts of traditional Chinese medicine to simultaneously regulate intestinal flora, enhance immunity, and purify water, overcoming the functional limitations of single components.

[0017] This research solves the technical problems of low feed nutrient absorption, frequent intestinal diseases, and water quality deterioration in sea cucumber farming. The combination of compound probiotics and traditional Chinese medicine extracts synergistically inhibits pathogen colonization, reducing the incidence of diseases such as skin rot syndrome; fermented substrates and seaweed powder improve protein utilization and reduce the pollution load of residual feed on the water; the combination of vitamin E and selenium yeast enhances the sea cucumber's resilience, enabling it to maintain normal growth under stress.

[0018] 2. By limiting the number of viable butyric acid bacteria, the ratio of fermentation substrate, and the physicochemical indicators of seaweed powder, a set of quantifiable and controllable technical standards has been formed.

[0019] This method solves the problem of intestinal dysfunction caused by insufficient butyric acid bacteria activity in traditional feed, improves the efficiency of protein digestion and absorption, and at the same time, by controlling the iodine and cellulose content of seaweed powder, it not only meets the metabolic needs of sea cucumbers, but also reduces the risk of pollution to the aquaculture water.

[0020] 3. This application addresses the problem of intestinal flora imbalance caused by the single type of traditional probiotics. By combining compound lactic acid bacteria with specific Bacillus species, it achieves simultaneous optimization of feed digestibility and ammonia nitrogen concentration in the water. The introduction of Rhodopseudomonas palustris transforms uneaten feed decomposition products into a form that can be absorbed by algae, reducing the frequency of water changes and aquaculture costs.

[0021] 4. This solution addresses the issues of high toxicity and low bioavailability of inorganic sodium selenite by precisely defining the ratio of a specific organic selenium source to vitamin E. Furthermore, while existing technologies often rely on experience to determine the dosage of vitamin E and selenium separately, this solution establishes a synergistic dosage model, reducing the total dosage by 15%-20% while maintaining efficacy.

[0022] 5. This solution, through the combination of microcrystalline cellulose and diatomaceous earth and precise particle size control, not only improves the loading efficiency of the carrier but also enhances the compressive strength and disintegration resistance of the feed pellets, which is beneficial for the digestion and absorption of sea cucumbers after ingestion.

[0023] It solves the problems of poor encapsulation of fat-soluble components and easy breakage of feed particles caused by traditional carriers, and achieves stable delivery of nutrients. At the same time, it optimizes the physical properties of feed and reduces component loss during processing.

[0024] 6. This scheme uses an enzyme ratio of 3:2:1 to ensure the efficient utilization of seaweed powder while taking into account the synergistic decomposition of animal protein and plant fiber, thus achieving simultaneous processing of multiple substrate components.

[0025] It effectively improves the bioavailability of iodine in seaweed powder and promotes the synthesis of mucopolysaccharides in sea cucumber epidermis; at the same time, it reduces the retention time of undigested protein in the intestine and reduces the accumulation of ammonia nitrogen metabolites; the compound enzyme system can also destroy the cell wall structure of traditional Chinese medicine, making the active ingredients such as astragalus polysaccharides easier to absorb and enhancing the immune regulation effect.

[0026] 7. This method uses a specific mixing ratio to enable Bifidobacterium bifidum to form a local anaerobic microenvironment with the help of Lactobacillus plantarum metabolites, thereby achieving effective colonization of the entire gut.

[0027] This invention solves the problem of the limited function of probiotics in traditional sea cucumber feed additives. Through the synergistic effect of Lactobacillus plantarum and Bifidobacterium bifidum, it enhances the intestinal immune function of sea cucumbers while inhibiting pathogenic bacteria, reduces the incidence of scab disease, and promotes the absorption and utilization of unsaturated fatty acids in the feed.

[0028] 8. This solution combines carrier functionalization modification with the application of cold-resistant strains to improve low-temperature feeding efficiency while achieving in-situ water purification.

[0029] This study solved the problems of low feed utilization, probiotic inactivation, and water quality deterioration in sea cucumbers under low-temperature conditions. The photocatalytic properties of the porous carrier reduced the frequency of water exchange, and the combination of Antarctic krill powder and cold-resistant strains enhanced the cold resistance and metabolic capacity of sea cucumbers, avoiding growth stagnation caused by low-temperature stress. Attached Figure Description

[0030] Figure 1 Line graph showing the effect of butyric acid bacteria addition on sea cucumber growth rate (SGR); Figure 2 Line graph showing the effect of the amount of compound probiotics added on intestinal flora diversity; Figure 3 Line graph showing the effect of the amount of Chinese herbal extract added on lysozyme activity; Figure 4 Line graph showing the effect of Antarctic krill meal addition on low-temperature feeding rate; Figure 5 The graph shows the effect of the amount of compound enzyme preparation added on feed digestibility.

[0035] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Detailed Implementation

[0036] To more clearly illustrate the overall concept of the present invention, a detailed description will be provided below with reference to the accompanying drawings and examples.

[0037] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0038] Furthermore, in the description of this invention, it should be understood that the terms "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0039] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0040] In this invention, unless otherwise expressly specified and limited, the first feature "on" or "below" the second feature may be in direct contact with the first and second features, or indirect contact through an intermediate medium. In the description of this specification, references to terms such as "implementation," "example," "aspect," "specific example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0041] Those skilled in the art will understand that, in existing technologies, sea cucumber farming has long faced problems such as unbalanced feed nutrition, frequent intestinal diseases, and water quality deterioration. Traditional feeds, mainly composed of fishmeal and soybean meal, lack essential amino acids and functional components, resulting in slow growth and poor disease resistance in sea cucumbers. Existing technologies have attempted to improve feed performance by adding single probiotics or traditional Chinese medicines, but these have not solved the problem of synergistic effects between microorganisms and plant components, and have failed to achieve the dual goals of intestinal health and water quality control.

[0042] To address the aforementioned issues, the inventors discovered that the combination of complex microbial flora and specific traditional Chinese medicines can form a dual pathway of antibacterial and immune regulation, while the combination of fermentation substrate and seaweed powder can simultaneously improve nutrient absorption efficiency. By screening specific proportions of butyric acid bacteria, complex probiotics, and traditional Chinese medicine extracts, a multi-component synergistic system was constructed to achieve a synergistic effect between feed fortification and aquatic environment improvement.

[0043] Therefore, this application proposes a sea cucumber aquaculture feed additive comprising fish meal, butyric acid bacteria, compound probiotics, traditional Chinese medicine extracts, fermentation substrate, seaweed powder, vitamin E, selenium yeast, and a carrier. The fish meal comprises 45%-55% by weight, butyric acid bacteria 2%-3%, compound probiotics 25%-30%, traditional Chinese medicine extracts 2%-4%, fermentation substrate 8%-12%, seaweed powder 10%-15%, vitamin E 0.5%-1%, selenium yeast 0.5%-1%, with the remainder supplemented by the carrier. The compound probiotics consist of lactic acid bacteria, Bacillus, and photosynthetic bacteria in a 2:1:1 mass ratio, and the traditional Chinese medicine extract is a mixture of Astragalus polysaccharide and Asarum extract in a 3:1 mass ratio.

[0044] Among them, compound probiotics refer to a mixed bacterial flora composed of lactic acid bacteria, Bacillus, and photosynthetic bacteria. Specifically, it can be achieved using *Lactobacillus plantarum*, *Bacillus subtilis*, and *Rhodopseudomonas palustris*. When mixed in a specific ratio, these three bacteria can create a microenvironment in the intestines that competitively inhibits pathogenic bacteria. Traditional Chinese medicine extracts refer to a combination of Astragalus polysaccharide and Asarum extract. Specifically, these can be extracted separately using water extraction and alcohol precipitation methods, and then compounded in a specific ratio to exert both antibacterial and immunomodulatory functions. Fermentation substrates refer to organic materials that have undergone microbial metabolic treatment. Specifically, a mixture of fish slurry and shrimp slurry can be used. After fermentation by lactic acid bacteria and butyric acid bacteria, small molecule peptides are generated, promoting the digestion and absorption of protein by sea cucumbers.

[0045] Specifically, fishmeal serves as the primary protein source, providing essential amino acids. Butyric acid bacteria metabolize and produce butyric acid, enhancing the intestinal epithelial barrier function. Lactic acid bacteria in the probiotic blend lower intestinal pH by producing lactic acid, inhibiting pathogens; Bacillus secretes antimicrobial peptides to directly kill harmful bacteria; and photosynthetic bacteria degrade ammonia nitrogen pollutants in the water. Astragalus polysaccharides from traditional Chinese medicine extracts activate the phagocytic activity of sea cucumber immune cells, while Asarum extract inhibits the proliferation of pathogenic bacteria such as Vibrio. Acid-soluble proteins in the fermentation substrate are broken down into easily absorbed short peptides, and alginate polysaccharides in seaweed powder form a gel-like substance with cellulose, slowing the passage of feed through the digestive tract and improving nutrient utilization. Vitamin E and selenium yeast work synergistically to scavenge free radicals, reducing the impact of oxidative stress on sea cucumber growth.

[0046] Compared to existing technologies, traditional solutions use only single probiotics or traditional Chinese medicine ingredients, failing to create a multi-pathway synergistic mechanism. This solution, through a combination of complex microbiota and traditional Chinese medicine extracts, simultaneously achieves intestinal flora regulation, immune enhancement, and water purification, overcoming the functional limitations of single ingredients.

[0047] Through the above technical solutions, this application solves the technical problems of low feed nutrient absorption rate, easy occurrence of intestinal diseases, and water quality deterioration in sea cucumber farming. The compound probiotics and traditional Chinese medicine extracts synergistically inhibit pathogen colonization, reducing the incidence of diseases such as skin rot syndrome; the fermented substrate and seaweed powder improve protein utilization and reduce the pollution load of residual feed on the water; the combination of vitamin E and selenium yeast enhances the sea cucumber's resistance to stress, enabling it to maintain normal growth under stressful conditions.

[0048] This application further specifies that the butyric acid bacteria are Clostridium butyricum, with a viable count ≥1×10⁹ CFU / g, and the addition amount is 2%-3% of the total mass; the fermentation substrate is a liquid substrate of fish slurry and shrimp slurry mixed at a mass ratio of 2:1, with an acid-soluble protein content ≥30%; the seaweed powder is selected from at least one of kelp powder and Sargassum powder, with an iodine content ≥200mg / kg and a cellulose content ≤15%.

[0049] Clostridium butyricum refers to an anaerobic bacterium capable of metabolizing butyric acid. It can be added as a powder with a viable count of at least 1×10⁹ CFU / g. At high concentrations, it can effectively promote the synthesis of short-chain fatty acids in the sea cucumber intestine. The fermentation substrate refers to a liquid matrix formed by mixing fish lysate and shrimp slurry. A mixture with a mass ratio of 2:1 can be used, and the acid-soluble protein content should be controlled to be at least 30% to improve protein bioavailability. Seaweed powder refers to pulverized seaweed raw materials. Specifically, kelp powder or Sargassum powder with an iodine content of at least 200 mg / kg and a cellulose content of no more than 15% can be used. Its high iodine content can promote thyroid function in sea cucumbers, and its low cellulose content can reduce the accumulation of undigested fiber in the water.

[0050] Specifically, the viable count of Clostridium butyricum is controlled to be no less than 1×10⁹ CFU / g, and combined with an addition amount of 2%-3% of the total mass, this ensures a stable colonization environment in the sea cucumber's intestines. The liquid substrate formed by mixing fish lysate and shrimp lysate in a 2:1 ratio, when the acid-soluble protein content reaches above 30%, can synergistically improve protein degradation efficiency with probiotics. The seaweed powder used is kelp powder or Sargassum powder with iodine content meeting standards, while the cellulose content is limited to below 15% to prevent undigested fiber from accumulating at the bottom of the aquaculture pond.

[0051] Compared to existing technologies, traditional feed additives typically contain fewer than 1×10⁸ CFU / g of live butyric acid bacteria, and lack a clearly defined mixing ratio between fish slurry and shrimp slurry, resulting in insufficient protein utilization. Existing seaweed powders generally have an iodine content below 150 mg / kg and a cellulose content exceeding 20%, easily leading to eutrophication. This proposed solution, however, establishes a set of quantifiable and controllable technical standards by specifying the live butyric acid bacteria count, fermentation substrate ratio, and physicochemical indicators of seaweed powder.

[0052] Through the above technical solution, this application solves the problem of intestinal dysfunction caused by insufficient butyric acid bacteria activity in traditional feed, improves the digestion and absorption efficiency of protein, and at the same time, by controlling the iodine and cellulose content of seaweed powder, it not only meets the metabolic needs of sea cucumbers, but also reduces the risk of pollution to the aquaculture water.

[0053] This application further proposes that the lactic acid bacteria are a mixture of Lactobacillus plantarum and Lactobacillus acidophilus, the Bacillus is Bacillus subtilis, and the photosynthetic bacteria is Rhodopseudomonas palustris.

[0054] The mixture of *Lactobacillus plantarum* and *Lactobacillus acidophilus* refers to a combination of two lactic acid bacteria, specifically achieved by mixing *Lactobacillus plantarum* and *Lactobacillus acidophilus* in a specific mass ratio. This combination synergistically maintains the acidic environment of the intestine and inhibits the proliferation of putrefactive bacteria by producing lactic acid and short-chain fatty acids, respectively. *Bacillus subtilis* is a spore-forming bacterium, specifically achieved using live *Bacillus subtilis* preparations. This bacterium promotes the degradation of macromolecules in feed by secreting amylase and protease, improving the digestibility of fishmeal and shrimp paste in sea cucumbers. *Rhodopseudomonas palustris* is a photosynthetic bacterium, specifically achieved using liquid cultures of *Rhodopseudomonas palustris*. This bacterium consumes ammonia nitrogen and hydrogen sulfide in the water through photosynthesis, reducing the toxic substances produced by the decomposition of uneaten feed.

[0055] Specifically, *Lactobacillus plantarum* and *Lactobacillus acidophilus* form a complex intestinal flora. The former lowers the intestinal pH by metabolizing lactose to produce lactic acid, while the latter metabolizes dietary fiber to produce propionic and butyric acids. Together, they enhance the intestinal barrier function. *Bacillus subtilis* forms a biofilm on the surface of feed pellets, and its secreted extracellular enzymes bind to fishmeal proteins during pelleting, shortening the digestion time of sea cucumbers. *Rhodopseudomonas palustris*, after entering the water, utilizes light conditions to decompose nitrogenous compounds in uneaten feed, forming nitrates that can be utilized by algae, thus achieving water self-purification.

[0056] Compared to existing technologies, traditional techniques using only a single lactic acid bacteria cannot create an acid-producing gradient environment, resulting in limited effects on gut microbiota regulation. However, Bacillus subtilis, instead of conventional Bacillus licheniformis, produces proteases with higher thermal stability, leading to improved survival rates in the granulation process. While existing photosynthetic bacteria often employ Rhodospirillum, Rhodopseudomonas palustris exhibits superior ammonia nitrogen removal efficiency under low-light conditions.

[0057] Through the above technical solution, this application solves the problem of intestinal flora imbalance caused by the single type of traditional probiotics. By combining compound lactic acid bacteria with specific Bacillus species, it achieves simultaneous optimization of feed digestibility and ammonia nitrogen concentration in the water. The introduction of Rhodopseudomonas palustris transforms the decomposition products of uneaten feed into a form that can be absorbed by algae, reducing the frequency of water changes and aquaculture costs.

[0058] This application further proposes that the mass ratio of vitamin E to selenium yeast is 1:1, and the total addition amount is 1%-2%.

[0059] Vitamin E, a fat-soluble antioxidant, can be obtained from natural tocopherol extracts. Its function is to protect cell membranes from oxidative damage and participate in immune regulation. Selenium yeast, a yeast culture containing organic selenium, can be prepared through fermentation in a selenium-enriched medium. Its function is to provide bioavailable selenium and enhance the activity of antioxidant enzyme systems. The 1:1 mass ratio is based on the need for synergistic effects between the two; for example, vitamin E prevents the oxidative loss of selenium, while selenium promotes the regeneration and recycling of vitamin E. The total addition is controlled within the range of 1%-2% to balance nutritional fortification and cost control. For example, too low a concentration may not meet the needs of sea cucumbers during their stress period, while too high a concentration may interfere with the absorption of other nutrients.

[0060] Specifically, in the preparation of feed additives, vitamin E and selenium yeast are premixed in equal mass ratios. For example, powdered vitamin E and selenium yeast powder are uniformly dispersed using a three-dimensional mixing device. This premix is ​​then added to the main ingredient at a standard mass ratio of 1%-2%, for example, simultaneously with other components before granulation. During this process, vitamin E protects the integrity of intestinal epithelial cells by blocking the lipid peroxidation chain reaction, while selenomethionine from selenium yeast enhances the activity of antioxidant enzymes in sea cucumbers by integrating into glutathione peroxidase molecules. The synergistic effect of both is manifested in the following way: under stress conditions such as high temperature or low oxygen, vitamin E preferentially scavenge free radicals, which are then reduced and regenerated by the selenium-dependent enzyme system, forming a sustained antioxidant protection mechanism.

[0061] This solution addresses the issues of high toxicity and low bioavailability of inorganic sodium selenite by precisely defining the ratio of a specific organic selenium source to vitamin E. Furthermore, while existing technologies often rely on experience to determine the dosage of vitamin E and selenium separately, this solution establishes a synergistic dosage model, reducing the total dosage by 15%-20% while maintaining efficacy.

[0062] Through the above technical solutions, this application effectively enhances the antioxidant stress resistance of sea cucumbers under fluctuating aquaculture environments, significantly reducing the incidence of intestinal mucosal oxidative damage when water temperatures rise in summer or dissolved oxygen decreases in winter. Simultaneously, this formulation design avoids the loss of selenium during feed processing; for example, in the high-temperature pelleting process, the presence of vitamin E increases the thermal stability of selenium yeast by approximately 30%. Furthermore, the precise addition range makes feed costs controllable; for example, while ensuring the selenium content per kilogram of feed meets standards, the amount of selenium raw materials used is reduced by approximately 25% compared to conventional addition methods.

[0063] This application further proposes that the carrier in the sea cucumber aquaculture feed additive is a mixture of microcrystalline cellulose and diatomaceous earth with a particle size of 80-120 mesh and an oil absorption rate of ≥150%.

[0064] Among them, microcrystalline cellulose refers to a crystalline powder obtained from the partial hydrolysis of cellulose, specifically pharmaceutical-grade microcrystalline cellulose, which, as a carrier, can improve the mechanical strength and disintegration stability of feed pellets. Diatomaceous earth refers to a porous mineral material formed from diatom fossils, specifically food-grade diatomaceous earth that has undergone high-temperature calcination, whose high specific surface area and porous structure are conducive to the adsorption and slow release of liquid nutrients. Particle size of 80-120 mesh refers to the mesh size range of particles passing through a standard sieve, which can be achieved by controlling the particle size distribution using airflow milling and classification processes. This range is conducive to the uniform mixing of the carrier with other powdery components. Oil absorption rate ≥150% means that the mass of oil adsorbed per unit mass of carrier is more than 1.5 times its own mass, which can be achieved by adjusting the porosity of diatomaceous earth and surface modification processes to ensure a stable loading of fat-soluble components.

[0065] Specifically, after microcrystalline cellulose and diatomaceous earth are mixed in a specific ratio, and the particle size is controlled within the range of 80-120 mesh, the carrier particles can be uniformly dispersed in the feed matrix, avoiding localized clumping. The binding effect of microcrystalline cellulose and the adsorption capacity of diatomaceous earth synergistically enhance the physical stability of the feed particles, especially in forming a structure with appropriate porosity during the granulation process. The oil absorption rate ensures that the carrier effectively encapsulates fat-soluble components such as vitamin E, reducing oxidative losses during processing and storage.

[0066] Compared to existing technologies, traditional feed additives often use a single carrier (such as starch or calcium carbonate alone), which suffers from insufficient oil absorption capacity leading to lipid loss, and the wide particle size distribution of the carrier easily causes uneven mixing. This solution, through the combination of microcrystalline cellulose and diatomaceous earth, combined with precise particle size control, not only improves the carrier's loading efficiency but also enhances the compressive strength and disintegration resistance of the feed pellets, which is beneficial for the digestion and absorption of sea cucumbers after ingestion.

[0067] Through the above technical solution, this application solves the problems of poor encapsulation effect of traditional carriers on fat-soluble components and easy breakage of feed particles, realizes stable delivery of nutrients, optimizes the physical properties of feed, and reduces component loss during processing.

[0068] This application further proposes that it also includes a complex enzyme preparation comprising 0.5%-1% of the total amount, the complex enzyme preparation being composed of neutral protease, xylanase and alginate lyase in an activity unit ratio of 3:2:1.

[0069] Among them, compound enzyme preparations refer to a combination of biocatalysts that promote feed digestion through the synergistic effect of multiple enzymes. Specifically, this can be achieved using a mixed system of neutral protease and xylanase. Neutral protease can break down animal proteins in fishmeal to produce small peptides, xylanase can degrade the cell wall structure of plant-based raw materials, and alginate lyase can cleave alginic acid in seaweed powder. This combination solves the problem of single-target action of traditional single enzyme preparations by releasing the decomposition capabilities of different substrates in stages.

[0070] Specifically, during feed processing, neutral proteases preferentially act on large protein molecules in fishmeal, hydrolyzing them into easily absorbed small peptides. Subsequently, xylanase breaks down the cellulose structure in herbal extracts and carriers, releasing encapsulated nutrients. Finally, alginate lyase continuously breaks down the cell walls of seaweed powder in the intestinal environment, ensuring the full release of iodine and minerals. This three-stage enzymatic hydrolysis process forms a spatiotemporally ordered chain of action, ensuring the stepwise release of various nutrients.

[0071] Compared to existing technologies, which use only alginate lyase to treat seaweed powder without considering the enzymatic hydrolysis requirements of other components in fish meal and traditional Chinese medicine, resulting in limited improvement in overall digestibility, this proposed solution uses an enzyme ratio of 3:2:1 to ensure efficient utilization of seaweed powder while also facilitating the synergistic decomposition of animal protein and plant fiber, achieving simultaneous processing of multiple substrate components.

[0072] Through the above technical solutions, this application effectively improves the bioavailability of iodine in seaweed powder and promotes the synthesis of mucopolysaccharides in sea cucumber epidermis; at the same time, it reduces the retention time of undigested protein in the intestine and reduces the accumulation of ammonia nitrogen metabolites; the compound enzyme system can also destroy the cell wall structure of traditional Chinese medicine, making it easier for active ingredients such as astragalus polysaccharides to be absorbed and enhancing the immune regulation effect.

[0073] This application further proposes that the lactic acid bacteria in the compound probiotics are a mixture of Lactobacillus plantarum and Bifidobacterium bifidum, and the mass ratio of the two is 3:1.

[0074] Among them, *Lactobacillus plantarum* refers to strains of Gram-positive bacteria that have the function of producing lactic acid, such as *Lactobacillus plantarum* CGMCC No. 1237, which lowers the intestinal pH value and inhibits the growth of pathogenic bacteria by producing lactic acid through the metabolism of carbohydrates; *Bifidobacterium bifidum* refers to probiotics that can colonize the intestines of sea cucumbers and secrete immunoglobulin-stimulating factors, such as *Bifidobacterium bifidum* ATCC 29521, which enhances the disease resistance of sea cucumbers by activating intestinal lymphoid tissue; the selection of a mass ratio of 3:1 is based on the synergistic matching of the two strains in acid production rate and immune regulation function, ensuring a dynamic balance between intestinal acidification and immune activation.

[0075] Specifically, *Lactobacillus plantarum*, at an addition rate of 1 × 10^8 CFU per gram of feed, rapidly produces lactic acid, lowering the pH of the anterior intestinal tract of sea cucumbers to 5.5-6.0, thus inhibiting the growth of pathogenic bacteria such as Vibrio; *Bifidobacterium bifidum*, at an addition rate of 3 × 10^8 CFU per gram of feed... 7 CFU concentrations activate intestinal Pierre node lymphocytes, promoting increased secretory IgA production. When the two strains are mixed in a 3:1 ratio, the acid production of *Lactobacillus plantarum* creates an anaerobic environment for *Bifidobacterium bifidum*, while the acetic acid produced by *Bifidobacterium bifidum* metabolism promotes the formation of *Lactobacillus plantarum* biofilm, thus forming a symbiotic relationship.

[0076] Compared to existing technologies, traditional methods that use only a single Lactobacillus or a combination of Lactobacillus acidophilus fail to address the immune regulation needs of the hindgut in sea cucumbers. This method, through a specific mixing ratio, enables Bifidobacterium bifidum to form a local anaerobic microenvironment with the help of Lactobacillus plantarum metabolites, achieving effective colonization throughout the entire gut.

[0077] Through the above technical solution, this application solves the problem of the single function of probiotics in traditional sea cucumber feed additives. Through the synergistic effect of Lactobacillus plantarum and Bifidobacterium bifidum, it can enhance the intestinal immune function of sea cucumbers while inhibiting pathogenic bacteria, reduce the incidence of scab disease, and promote the absorption and utilization rate of unsaturated fatty acids in feed.

[0078] This application further proposes an optimized scheme for sea cucumber aquaculture feed additives in low-temperature environments. Specifically, the carrier is porous diatomaceous earth particles loaded with nano-titanium dioxide, with a particle size of 50-100 micrometers and a specific surface area of ​​not less than 200 square meters per gram. The nano-titanium dioxide loading is 0.5%-1% of the carrier mass. When used in low-temperature aquaculture environments, an additional 1%-2% of Antarctic krill powder is added, and the compound probiotics are replaced with cold-resistant strains, with a mass ratio of 2:1.

[0079] Among them, porous diatomaceous earth particles refer to diatomaceous earth-based carrier materials with high porosity, which can be prepared by acid washing and pore-expanding process. Their high specific surface area can enhance the adsorption and slow release capacity of active ingredients; nano-titanium dioxide loading refers to titanium dioxide nanoparticles uniformly distributed on the surface of the carrier by sol-gel method or impregnation method, which have the function of photocatalytic degradation of organic pollutants; Antarctic krill powder refers to animal protein source made by low-temperature drying and pulverization of Antarctic krill, which is rich in astaxanthin and low-temperature active enzymes; cold-resistant strains refer to microbial strains that can maintain metabolic activity below 10℃, such as Pseudomonas or Flavobacterium strains isolated from polar environments.

[0080] Specifically, when the aquaculture water temperature is below 10℃, the metabolic activity of conventional probiotics decreases significantly, leading to a decline in feed utilization. By using a porous diatomaceous earth carrier, its nano-titanium dioxide can decompose ammonia nitrogen pollutants in the water under weak light, while the carrier's large specific surface area can adsorb and slowly release active ingredients. The addition of Antarctic krill powder can supplement the sea cucumber's need for essential fatty acids and antioxidants in low-temperature environments, and the combination of cold-resistant strains and conventional probiotics in a certain proportion can maintain colonization ability in the low-temperature intestinal environment, promoting the decomposition and absorption of nutrients.

[0081] Compared to existing technologies, traditional low-temperature aquaculture feeds typically increase the feeding amount directly to compensate for metabolic efficiency losses, but this leads to increased uneaten feed pollution. Commercially available cold-resistant feed additives mostly use single bacterial strains or physical heating devices, failing to form a synergistic system of carrier-strain-nutrients. This solution, through the combined application of carrier functionalization modification and cold-resistant bacterial strains, improves low-temperature feeding efficiency while achieving in-situ water purification.

[0082] Through the above technical solutions, this application solves the problems of low feed utilization, probiotic inactivation, and water quality deterioration in sea cucumbers under low-temperature conditions. The photocatalytic properties of porous carriers reduce the frequency of water exchange, and the combined use of Antarctic krill powder and cold-resistant strains enhances the cold-resistant metabolic capacity of sea cucumbers, avoiding growth stagnation caused by low-temperature stress.

[0083] This application further proposes a method for preparing a feed additive for sea cucumber farming. The preparation method includes the following steps: mixing fish slurry and shrimp slurry, adjusting the pH to 6.0-6.5, adding lactic acid bacteria and Clostridium butyricum, and fermenting at 30-35℃ for 48-72 hours to obtain a fermentation substrate; mixing and pulverizing fish meal, seaweed powder, traditional Chinese medicine extract, and carrier to 80-100 mesh; mixing the fermentation substrate with the mixture, compound probiotics, vitamin E, and selenium yeast and granulating to a particle diameter of 1-2 mm. During the fermentation process, zinc sulfate and ferrous sulfate, accounting for 0.1%-0.3% of the fermentation substrate mass, are added additionally, and the fermentation temperature is controlled in two stages: 30-32℃ for the first 24 hours to promote the proliferation of lactic acid bacteria; and 35-37℃ for the next 24-48 hours to activate Clostridium butyricum metabolism and acid production.

[0084] The mixed liquid substrate of fish slurry and shrimp slurry refers to an animal-derived protein source mixed at a mass ratio of 2:1. Specifically, it can be achieved by enzymatic hydrolysis of fresh fish processing by-products and shrimp head slurry, which can increase the acid-soluble protein content to over 30%, thus improving the nutrient utilization rate of the fermentation substrate. The combined fermentation of lactic acid bacteria and Clostridium butyricum utilizes the synergistic effect of *Lactobacillus plantarum*, *Lactobacillus acidophilus*, and *C. butyricum*. Through staged temperature control, the initial low temperature promotes acid production by lactic acid bacteria to lower the pH, while the subsequent temperature increase activates *C. butyricum* to metabolize butyric acid, thereby forming a short-chain fatty acid complex. The addition of zinc sulfate and ferrous sulfate serves as a trace element supplement. Specifically, zinc sulfate heptahydrate and ferrous sulfate monohydrate are mixed at a 1:1 molar ratio, dissolved in the fermentation broth, and uniformly dispersed to activate bacterial enzyme activity and enhance product stability. Mixing and pulverizing to 80-100 mesh refers to processing solid raw materials such as fish meal and seaweed powder using an ultra-fine pulverizer, increasing the specific surface area of ​​the material and facilitating the uniform dispersion of components during subsequent granulation.

[0085] Specifically, after mixing fish slurry and shrimp slurry, adjusting the pH to a slightly acidic environment can inhibit the growth of miscellaneous bacteria and promote the colonization of lactic acid bacteria. In the initial fermentation stage, a low temperature of 30-32℃ is conducive to the rapid proliferation of lactic acid bacteria, which lower the system pH by secreting lactic acid, creating an antibacterial environment. In the second stage, the temperature rises to 35-37℃, at which point the metabolic activity of Clostridium butyricum is activated, and its butyric acid synthesis efficiency is significantly improved with the assistance of zinc sulfate and ferrous sulfate. When the fermented substrate is mixed with the pulverized solid raw materials, a particle size of 80-100 mesh ensures effective adsorption of liquid components by the carrier while avoiding dust problems caused by excessively fine particles. During granulation, a particle diameter of 1-2 mm is designed to match the feeding characteristics of sea cucumber mouthparts, reducing feed loss and improving intestinal digestion and absorption efficiency.

[0086] In some specific embodiments, fish paste can be prepared from anchovy processing by-products through protease hydrolysis; shrimp paste can be prepared from the head paste of Litopenaeus vannamei through colloid milling; lactic acid bacteria can be prepared by inoculating freeze-dried Lactobacillus plantarum CICC 20279 and Lactobacillus acidophilus ATCC 4356 in a 1:1 ratio; Clostridium butyricum can be prepared by inoculating strain CGMCC 1.5132 at an inoculation amount of 0.5% of the fermentation substrate. The pulverizing process can use a circulating airflow pulverizer, controlling the feed rate at 50 kg / h and the pulverizing pressure at 0.8 MPa. During granulation, 5% by mass of carboxymethyl cellulose can be added as a binder, the granulator die diameter is set to 1.5 mm, and the output moisture content is controlled below 8%.

[0087] Compared to existing technologies, traditional fermentation processes often employ a single-temperature fermentation method. This scheme, through staged temperature control, allows two strains to function at their respective optimal temperatures. Simultaneously, the addition of zinc sulfate and ferrous sulfate as cofactors significantly increases butyric acid yield. This scheme utilizes an 80-100 mesh pulverization process, combined with carrier materials of specific particle sizes, to create a stable and homogeneous system between the liquid fermentation substrate and the solid powder.

[0088] Through the above technical solutions, this application has achieved the efficient preparation of sea cucumber feed additives, promoted the synergistic metabolism of lactic acid bacteria and butyric acid clostridium, and increased the production of short-chain fatty acids; the optimized crushing and granulation process enhances the stability and palatability of the feed; the combination strategy of staged temperature control and trace element addition effectively improves the functional activity of fermentation products, thereby improving the intestinal health of sea cucumbers and reducing the risk of ammonia nitrogen pollution in water bodies.

[0089] This application further proposes that, during the fermentation process in step one, zinc sulfate and ferrous sulfate, accounting for 0.1%-0.3% of the fermentation substrate mass, be added additionally, and the fermentation temperature is controlled in two stages: 30-32℃ for the first 24 hours to promote the proliferation of lactic acid bacteria; and 35-37℃ for the next 24-48 hours to activate Clostridium butyricum to produce acid.

[0090] Zinc sulfate and ferrous sulfate are two inorganic trace element supplements. Specifically, they can be added by mixing food-grade zinc sulfate and ferrous sulfate in a 1:1 mass ratio. Their function is to enhance the sugar metabolism efficiency of lactic acid bacteria by providing zinc and iron ions as coenzyme factors. Staged temperature control refers to dividing the fermentation process into two temperature zones. This can be achieved through segmented temperature-controlled fermenters or by transferring fermentation materials in batches. The lower temperature in the initial stage is conducive to the rapid occupation of the ecological niche by lactic acid bacteria, while the increased temperature in the later stage stimulates the acid-producing metabolic activity of Clostridium butyricum.

[0091] Specifically, in the early stages of fermentation of the fish slurry and shrimp slurry mixture, the addition of zinc sulfate and ferrous sulfate to form a metal ion complex system activates the lactate dehydrogenase activity of lactic acid bacteria, accelerating the decomposition of carbohydrates in the substrate. After 24 hours of fermentation, the temperature is adjusted to 35-37℃. At this temperature, the heat-resistant characteristics of Clostridium butyricum make it the dominant species, significantly increasing the production of butyric acid secreted under high-temperature conditions. The synergistic effect of temperature and trace elements in these two stages allows the metabolic pathways of lactic acid bacteria and Clostridium butyricum to complement each other, ensuring rapid colonization of the microbial community in the early stages of fermentation while achieving efficient synthesis of functional metabolites in the later stages.

[0092] Compared to existing technologies, traditional fermentation processes typically employ constant temperature conditions, leading to overlapping growth cycles among different microbial strains and resulting in metabolic competitive inhibition. Existing technologies add metal ions only as a single trace element supplement, without considering their differentiated regulatory effects on the metabolism of different strains. This approach achieves precise control of the metabolic sequence of the microbial community through a staged combination strategy of temperature and metal ions.

[0093] Through the above technical solution, this application can effectively improve the accumulation efficiency of beneficial metabolites in the fermentation substrate, promote the synergistic generation of butyric acid and lactic acid, thereby enhancing the absorption capacity of short-chain fatty acids in the sea cucumber intestine. Simultaneously, staged temperature control avoids the problem of bacterial activity inhibition under single temperature conditions, ensuring the stability and functionality of the fermentation products.

[0094] Example 1: Optimizing the best ratio for preparing compound feed additives, the formula is based on the following mass percentages: Fish meal: 50%; Butyric acid bacteria: 2.5% (live bacteria count ≥ 1×10⁻⁶) 9 CFU / g); Compound probiotics: 28% (Lactic acid bacteria: Bacillus: Photosynthetic bacteria = 2:1:1); Traditional Chinese medicine extracts: 3% (Astragalus polysaccharide: Asarum extract = 3:1); Fermentation substrate (fish lysate: shrimp lysate = 2:1): 10% (acid-soluble protein ≥30%); Seaweed powder (kelp powder): 12% (iodine content 220 mg / kg, cellulose 12%); Vitamin E + selenium yeast: 1.5% (1:1); Carrier (microcrystalline cellulose: diatomaceous earth = 1:1): balance.

[0096] The optimal preparation method:

[0097] (1) Preparation of fermentation substrate:

[0098] Fish slurry and shrimp slurry were mixed, the pH was adjusted to 6.2, and lactic acid bacteria (Lactobacillus plantarum) and Clostridium butyricum were inoculated. Fermentation was carried out at 32°C for 60 hours to obtain a fermentation broth with an acid-soluble protein content of 32%.

[0099] (2) Dry-mix component treatment:

[0100] Fish meal, seaweed powder, herbal extracts, and carrier are mixed and then pulverized to 90 mesh.

[0101] (3) Granulation and encapsulation:

[0102] The fermentation broth was mixed with dry components, compound probiotics (Bacillus subtilis, Lactobacillus acidophilus, Rhodopseudomonas palustris), vitamin E, and selenium yeast, granulated into 1.5mm particles, and dried at 40℃ until the moisture content was ≤8%.

[0103] The additive prepared according to the above ratio and method was added at 8% of the total feed mass and fed to juvenile sea cucumbers (initial weight 2g). After 60 days of breeding, the specific growth rate (SGR) reached 2.8% / day, the lysozyme activity increased by 35%, and the ammonia nitrogen concentration remained stable below 0.15mg / L.

[0104] Example 2: High Probiotic Ratio Formula

[0105] Formula adjustments:

[0106] Compound probiotics: 30% (lactic acid bacteria: Bacillus: photosynthetic bacteria = 3:1:1); butyric acid bacteria: 3%, the remaining components are the same as in Example 1.

[0107] Effect comparison: The gut microbiota diversity increased by 12% compared to Example 1, and the incidence of skin rot syndrome decreased by 40%.

[0108] Example 3: Low-cost alternative

[0109] Formula adjustments: Fish meal was replaced with 40% soybean meal hydrolyzed protein + 10% fish meal; fermentation substrate was replaced with pure fish slurry (25% acid-soluble protein).

[0110] Performance comparison: The specific growth rate (SGR) was 2.3% / day, and the cost was reduced by 20%, but it was still better than conventional feed (SGR 1.8% / day).

[0111] Example 4: Optimization of Microencapsulation Process

[0112] Preparation adjustment: Photosynthetic bacteria and nitrifying bacteria were encapsulated in sodium alginate microcapsules (particle size 50 μm) at an addition amount of 1.5%.

[0113] Water quality improvement: Ammonia nitrogen degradation cycle extended to 10 days, water change frequency reduced by 50%.

[0114] Comparative Examples

[0115] Comparative Example 1

[0116] Formula: 8% compound vitamins, 18% compound enzymes, 25% probiotics, 8% photosynthetic bacteria, 30% soybean meal, and 11% wheat flour.

[0117] Results data:

[0118] SGR was 2.0% / day, lysozyme activity increased by 18%, and ammonia nitrogen concentration was 0.3 mg / L.

[0119] Comparative Example 2 (without butyric acid bacteria and traditional Chinese medicine)

[0120] Formula: Butyric acid bacteria and herbal extracts are omitted and replaced with an equal amount of carrier.

[0121] Results data:

[0122] SGR decreased to 1.9% / day, lysozyme activity increased by only 10%, and ammonia nitrogen concentration rose to 0.4 mg / L.

[0123] Comparative Example 3 (Low Probiotic Ratio)

[0124] Formula: The compound probiotics were adjusted to 20% (lower limit of the scope of Patent 2), and the rest were the same as in Example 1.

[0125] Results data: The content of intestinal pathogens (Vibrio) increased by 2 times, and the survival rate decreased by 15%.

[0126] Comparative Example 4 (Conventional Feed)

[0127] Formula: Commercially available sea cucumber feed (35% fish meal, 40% soybean meal, 10% seaweed powder, 5% vitamin premix, and 10% minerals).

[0128] Results data: SGR was 1.5% / day, and ammonia nitrogen concentration fluctuated between 0.5 and 0.8 mg / L.

[0129] In addition, during the breeding period of broodstock, the amount of feed additives should be increased to 10% to 12%; feed should be given 3 times a day, and the feed should be soaked in an aqueous solution containing 0.1% seaweed polysaccharide for 30 minutes before each feeding to enhance the induction of gonadal development.

[0130] This formula is based on fish meal and fish oil, combined with butyric acid bacteria (to promote digestion), compound probiotics (lactic acid bacteria + Bacillus + photosynthetic bacteria) and traditional Chinese medicine extracts (Astragalus polysaccharide + Asarum extract) to form a multi-effect synergistic effect of "promoting growth - antibacterial - immune regulation".

[0131] Adding a compound enzyme preparation (neutral protease + xylanase + alginate lyase) specifically breaks down anti-nutritional factors in seaweed powder and releases small molecule active substances.

[0132] The porous diatomaceous earth carrier loaded with nano-titanium dioxide combines the functions of vitamin stable preservation and photocatalytic degradation of water pollutants.

[0133] For low-temperature environments (≤10℃), Antarctic krill powder is added and cold-resistant probiotic strains are replaced to maintain the low-temperature feeding activity of sea cucumbers.

[0134] A staged temperature-controlled fermentation process is used to regulate the ratio of metabolites of lactic acid bacteria and butyric acid bacteria, thereby increasing the butyric acid concentration (≥12mM).

[0135] Microencapsulated photosynthetic and nitrifying bacteria extend the water quality restoration cycle to 7-10 days.

[0136] For any parts not mentioned in this invention, existing technologies can be used or referenced.

[0137] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0138] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A sea cucumber aquaculture feed additive, characterized in that, Includes the following components by mass percentage: The formula contains 45%-55% fish meal, 2%-3% butyric acid bacteria, 25%-30% compound probiotics, 2%-4% traditional Chinese medicine extracts, 8%-12% fermentation substrate, 10%-15% seaweed powder, 0.5%-1% vitamin E, 0.5%-1% selenium yeast, and the remainder is a carrier. The compound probiotics are composed of lactic acid bacteria, Bacillus, and photosynthetic bacteria in a mass ratio of 2:1:

1. The traditional Chinese medicine extracts are a mixture of Astragalus polysaccharide and Asarum extract in a mass ratio of 3:

1.

2. The sea cucumber aquaculture feed additive according to claim 1, characterized in that, The butyric acid bacteria mentioned are Clostridium butyricum, with a viable count ≥1×10⁻⁶. 9 CFU / g, the amount added is 2%-3% of the total mass; The fermentation substrate is a liquid substrate made by mixing fish slurry and shrimp slurry in a mass ratio of 2:1, with an acid-soluble protein content of ≥30%. The seaweed powder is selected from at least one of kelp powder and Sargassum powder, with an iodine content ≥200mg / kg and a cellulose content ≤15%.

3. The sea cucumber aquaculture feed additive according to claim 1, characterized in that, The lactic acid bacteria are a mixture of Lactobacillus plantarum and Lactobacillus acidophilus; the Bacillus is Bacillus subtilis; and the photosynthetic bacteria is Rhodopseudomonas palustris.

4. The sea cucumber aquaculture feed additive according to claim 1, characterized in that, The mass ratio of vitamin E to selenium yeast is 1:1, and the total addition amount is 1%-2%.

5. The sea cucumber aquaculture feed additive according to claim 1, characterized in that, The carrier is a mixture of microcrystalline cellulose and diatomaceous earth with a particle size of 80-120 mesh and an oil absorption rate of ≥150%.

6. The sea cucumber aquaculture feed additive according to claim 1, characterized in that, It also contains 0.5%-1% of a complex enzyme preparation, which is composed of neutral protease, xylanase and alginate lyase in an activity unit ratio of 3:2:

1.

7. The sea cucumber aquaculture feed additive according to claim 6, characterized in that, The lactic acid bacteria in the compound probiotics are a mixture of Lactobacillus plantarum and Bifidobacterium bifidum, with a mass ratio of 3:

1.

8. The sea cucumber aquaculture feed additive according to claim 1, characterized in that, The carrier is porous diatomaceous earth particles loaded with nano-titanium dioxide, with a particle size of 50-100μm, a specific surface area ≥200m2 / g, and the nano-titanium dioxide loading is 0.5%-1% of the carrier mass. When used in low-temperature aquaculture environments (water temperature ≤10℃), add an additional 1%-2% of Antarctic krill powder to the total amount, and replace the compound probiotics with cold-resistant strains, with a mass ratio of 2:

1.

9. A method for preparing a sea cucumber aquaculture feed additive according to any one of claims 1-8, characterized in that, Its preparation method includes the following steps: Step 1: Mix fish paste and shrimp paste, adjust the pH to 6.0-6.5, add lactic acid bacteria and butyric acid bacteria, ferment at 30-35℃ for 48-72 hours to obtain fermentation substrate; Step 2: Mix and pulverize the fish meal, seaweed powder, herbal extracts, and carrier to 80-100 mesh; Step 3: Mix the fermentation substrate from Step 1 with the mixture from Step 2, compound probiotics, vitamin E, and selenium yeast, and granulate the mixture to a particle diameter of 1-2 mm.

10. The method for preparing a sea cucumber aquaculture feed additive according to claim 9, wherein in the fermentation process of step one, zinc sulfate and ferrous sulfate are added in addition at a mass of 0.1%-0.3% of the fermentation substrate, and the fermentation temperature is controlled in two stages: 30-32℃ for the first 24 hours to promote the proliferation of lactic acid bacteria; and 35-37℃ for the next 24-48 hours to activate Clostridium butyricum to produce acid.

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