Anti-stress functional composition, feed as well as preparation method and application of anti-stress functional composition

Abstract

The invention relates to the field of aquaculture feed, and particularly discloses an anti-stress functional composition, feed as well as a preparation method and application of the anti-stress functional composition. The anti-stress functional composition is prepared from L-theanine, tea polyphenol, a bighead atractylodes rhizome extract and beta-1, 3-glucan. According to the composition, through the synergistic effect of the L-theanine, the tea polyphenol, the rhizoma atractylodis macrocephalae extract and the beta-1, 3-glucan, the anti-stress ability of the scylla paramamosain can be remarkably enhanced, then the survival rate of the scylla paramamosain is increased, the vitality performance of the scylla paramamosain is improved, meanwhile, the long-distance transportation resistance of the scylla paramamosain is enhanced, and a guarantee is provided for subsequent breeding and circulation links. The invention relates to a feed for improving the anti-stress capability of scylla paramamosain and a preparation method thereof, which not only can accurately meet the core demand of the scylla paramamosain for improving the anti-stress capability, but also can solve the problems of unbalanced nutrition, easy carrying of pathogens and water pollution of the existing feed by optimizing a formula and a preparation process.

Description

Technical Field

[0001] This application relates to the field of aquaculture feed, and in particular to an anti-stress functional composition, feed, preparation method and application thereof. Background Technology

[0002] The mud crab (Scylla serrata) is a marine aquaculture crustacean with high economic value. Due to its advantages such as rapid growth, large size, and strong environmental adaptability, it is highly favored by consumers and occupies an important position in the aquaculture industry.

[0003] However, in actual farming of mud crabs, they often face various stressors, including drastic changes in water temperature, large fluctuations in salinity, continuous deterioration of water quality, excessively high stocking density, and invasion by pathogenic microorganisms. These stressors severely disrupt the normal physiological functions of mud crabs, leading to a significant decrease in their stress resistance, resulting in adverse consequences such as slow growth, reduced immunity, and increased morbidity. This not only seriously affects farming efficiency but also significantly reduces the quality of mud crab products.

[0004] Currently, mud crab farming still relies mainly on live feed, but live feed has inherent drawbacks such as unbalanced nutritional composition, susceptibility to pathogens, and pollution of the aquaculture water. Furthermore, the nutritional composition and formulation of existing formulated feeds for mud crabs do not fully consider the specific needs of improving their stress resistance, and therefore cannot effectively help them cope with the complex and ever-changing aquaculture environment. Therefore, developing a feed specifically designed to enhance the stress resistance of mud crabs has significant practical importance and broad market prospects. Summary of the Invention

[0005] In view of this, the purpose of this application is to provide an anti-stress functional composition, feed, preparation method and application thereof, to solve the technical problems of existing feeds being nutritionally unbalanced, prone to carrying pathogens, polluting water bodies, and unable to assist mud crabs in coping with environmental stress.

[0006] To achieve the above-mentioned technical objectives, this application provides an anti-stress functional composition comprising, by dry weight, the following components in percentage by mass: 40%–50% L-theanine, 20%–30% tea polyphenols, 10%–15% Atractylodes macrocephala extract, and 10%–15% β-1,3-glucan.

[0007] This application provides an application of an anti-stress functional composition for the preparation of feed or feed additives.

[0008] This application provides a feed comprising an anti-stress functional composition.

[0009] This application provides a feed for improving the stress resistance of mud crabs, comprising, by dry weight, the following components in percentage by weight: 30%–35% Peruvian fish meal, 2%–4% mussel meal, 12%–16% soybean meal, 2%–6% brewer's yeast powder, 8%–12% Antarctic krill meal, 15%–20% high-gluten flour, 1%–3% deep-sea fish oil, 1%–2% soybean lecithin oil, 0.5%–1% vitamins, 0.5%–1% minerals, 1.5%–2.5% calcium dihydrogen phosphate, 0.3%–0.5% choline chloride, 1.5%–2.5% cuttlefish paste, 0.1%–0.3% antioxidant BHT, and 1%–2% of the anti-stress functional composition of claim 1.

[0010] Furthermore, the vitamins contained in each ton of feed include: Vitamin A 4 million to 6 million IU, Vitamin D 2 million to 4 million IU, Vitamin E 100g to 200g, Vitamin K3 6g to 15g, Vitamin B1 4g to 8g, Vitamin B2 10g to 20g, Vitamin B6 10g to 15g, and Vitamin B... 12 20-30mg, Vitamin H 70-90mg, Niacin 40g-50g, Calcium Pantothenate 25g-35g, Folic Acid 1g-4g, Inositol 100g-200g, Vitamin C Monophosphate 800g-1200g, with the remainder being a carrier.

[0011] Furthermore, each ton of feed contains the following minerals: calcium 60-80g, phosphorus 80-100g, potassium 70-90g, magnesium 10-20g, iron 1-3g, zinc 15-20g, copper 2-5g, cobalt 150mg-180mg, iodine 40mg-60mg, selenium 3mg-5mg, with the remainder being a carrier.

[0012] Furthermore, Peruvian fishmeal contains over 64% crude protein by mass, while soybean meal contains over 46% crude protein by mass.

[0013] This application provides a method for preparing feed to improve the stress resistance of mud crabs, comprising the following steps:

[0014] Step S1: Mix vitamins, minerals, calcium dihydrogen phosphate, choline chloride, antioxidant BHT, and an anti-stress functional composition to obtain a first mixture; grind Peruvian fish meal, mussel meal, soybean meal, brewer's yeast powder, Antarctic krill powder, and high-gluten flour to obtain a second mixture.

[0015] Step S2: Mix the first mixture with the second mixture and then perform ultra-fine pulverization to obtain the third mixture;

[0016] Step S3: Add deep-sea fish oil, soybean lecithin oil and squid paste to the third mixture, mix evenly, granulate, and then cook and cool to obtain feed.

[0017] Furthermore, the ripening conditions are: maintaining at 100–105°C for 40–50 minutes.

[0018] This application provides an application of feed to improve the stress resistance of mud crabs, used to increase the survival rate of mud crabs and / or reduce their stress response.

[0019] In summary, this application provides an anti-stress functional composition comprising L-theanine, tea polyphenols, Atractylodes macrocephala extract, and β-1,3-glucan. Through the synergistic effect of L-theanine, tea polyphenols, Atractylodes macrocephala extract, and β-1,3-glucan, this composition significantly enhances the stress resistance of *Scylla serrata*, thereby increasing its survival rate and vitality. It also enhances the *Scylla serrata*'s tolerance to long-distance transportation, providing assurance for subsequent aquaculture and distribution.

[0020] This application provides a feed to enhance the stress resistance of mud crabs, comprising Peruvian fish meal, mussel meal, soybean meal, brewer's yeast powder, Antarctic krill meal, high-gluten flour, deep-sea fish oil, soybean lecithin oil, vitamins, minerals, calcium dihydrogen phosphate, choline chloride, cuttlefish paste, antioxidant BHT, and an anti-stress functional composition. By adding highly effective attractants such as cuttlefish paste and mussel meal, this application ensures that mud crabs maintain a strong appetite under stress, achieving rapid feeding and growth, while reducing feed waste and water pollution, and lowering the feed conversion ratio. Furthermore, this application increases the content of vitamin C monophosphate in the feed to 800g-1200g / ton and vitamin E content to 100g-200g / ton, significantly higher than conventional feed dosages. This strongly supports the mud crab in scavenging stress-generated free radicals under stress conditions, greatly enhancing its resistance to adverse environments. In addition, all raw materials used are compliant feed ingredients, free of artificial colors and illegal chemical additives, and fully comply with relevant national safety and feed hygiene standards, ensuring the nutritional value and food safety of mud crabs from the source.

[0021] This application provides a method for preparing feed to improve the stress resistance of mud crabs, comprising the following steps: mixing vitamins, minerals, calcium dihydrogen phosphate, choline chloride, antioxidant BHT, and an anti-stress functional composition to obtain a first mixture; pulverizing Peruvian fish meal, mussel meal, soybean meal, brewer's yeast powder, Antarctic krill powder, and high-gluten flour to obtain a second mixture; mixing the first mixture and the second mixture and then performing ultra-fine pulverization to obtain a third mixture; adding deep-sea fish oil, soybean lecithin oil, and squid paste to the third mixture, mixing evenly, granulating, and then maturing and cooling to obtain the feed. The granulation and maturation process used in this application can effectively reduce the pathogen carrying rate of the feed, improve the water resistance and stability of the feed, significantly reduce the amount of feed lost in water, and reduce direct pollution to aquaculture water bodies.

[0022] Compared with existing technologies, the anti-stress functional composition, feed and preparation method of this application can not only accurately meet the core needs of mud crabs to improve their anti-stress ability, but also solve the defects of nutritional imbalance, easy pathogen carrying and water pollution by optimizing the formula and preparation process. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments in this application specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection claimed in this application.

[0024] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship shown, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] Unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0026] The raw materials used in this invention are not particularly restricted in their source; they can be purchased on the market or prepared using conventional methods known to those skilled in the art.

[0027] This application provides an anti-stress functional composition comprising, by dry weight, the following components in percentage by mass: 40%–50% L-theanine, 20%–30% tea polyphenols, 10%–15% Atractylodes macrocephala extract, and 10%–15% β-1,3-glucan.

[0028] It should be noted that L-theanine, tea polyphenols, Atractylodes macrocephala extract, and β-1,3-glucan each possess unique and complementary biological functions. When used in appropriate weight proportions, they can synergistically enhance the stress resistance of *Scylla serrata* through multiple pathways. The specific mechanisms of action are as follows: L-theanine, as a major free amino acid in tea, can regulate neurotransmitter release and target the reduction of stress hormone levels such as cortisol in *Scylla serrata*, thereby mitigating the interference of stress on the physiological functions of the crab from the source. Tea polyphenols possess strong antioxidant activity, which can quickly eliminate the large number of peroxide free radicals generated by crabs under stress, preventing cells from suffering oxidative damage, protecting cell membrane integrity and organelle function, and providing direct protection against stress damage. Atractylodes macrocephala extract has the effects of invigorating the spleen and replenishing qi, and enhancing immunity. On the one hand, it can improve the constitution of mud crabs and enhance their basic stress resistance; on the other hand, it can regulate key metabolic indicators such as cortisol, lactic acid, and blood sugar by acting on the hypothalamus-pituitary-adrenal cortex axis, thereby alleviating the negative effects of stress on aquaculture animals from a metabolic perspective. β-1,3-glucan can form a complex with glucan-binding proteins in mud crabs, thereby activating the immune system, promoting the proliferation of immune cells and enhancing their activity, and enhancing the body's resistance to pathogens and stressful environments. It complements the other three components, synergistically amplifying the anti-stress effect.

[0029] In some preferred embodiments, the anti-stress functional composition comprises, by dry weight, the following components in percentage by weight: 50% L-theanine, 20% tea polyphenols, 15% Atractylodes macrocephala extract, and 15% β-1,3-glucan.

[0030] This application provides an application of an anti-stress functional composition for the preparation of feed or feed additives.

[0031] This application provides a feed comprising an anti-stress functional composition.

[0032] This application provides a feed for improving the stress resistance of mud crabs, comprising the following components by weight percentage: 30%–35% Peruvian fish meal, 2%–4% mussel meal, 12%–16% soybean meal, 2%–6% brewer's yeast powder, 8%–12% Antarctic krill meal, 15%–20% high-gluten flour, 1%–3% deep-sea fish oil, 1%–2% soybean lecithin oil, 0.5%–1% vitamins, 0.5%–1% minerals, 1.5%–2.5% calcium dihydrogen phosphate, 0.3%–0.5% choline chloride, 1.5%–2.5% cuttlefish paste, 0.1%–0.3% antioxidant BHT, and 1%–2% of the anti-stress functional composition of claim 1.

[0033] In some preferred embodiments, the feed comprises, by dry weight, the following components in percentage by weight: 36% Peruvian fish meal, 3% mussel meal, 15% soybean meal, 5% brewer's yeast powder, 12% Antarctic krill meal, 18% high-gluten flour, 2% deep-sea fish oil, 1% soybean lecithin oil, 1% vitamins, 1% minerals, 2% calcium dihydrogen phosphate, 0.3% choline chloride, 2% squid extract, 0.2% antioxidant BHT, and 1.5% anti-stress functional composition.

[0034] In some preferred embodiments, the Peruvian fishmeal contains more than 64% crude protein by mass, and the soybean meal contains more than 46% crude protein by mass.

[0035] In some embodiments, per ton of feed, on a dry weight basis, the vitamins comprise the following components: Vitamin A 4 million IU to 6 million IU, Vitamin D 2 million IU to 4 million IU, Vitamin E 100g to 200g, Vitamin K3 6g to 15g, Vitamin B1 4g to 8g, Vitamin B2 10g to 20g, Vitamin B6 10g to 15g, Vitamin B... 12 20-30mg, Vitamin H 70-90mg, Niacin 40g-50g, Calcium Pantothenate 25g-35g, Folic Acid 1g-4g, Inositol 100g-200g, Vitamin C Monophosphate 800g-1200g, with the remainder being a carrier.

[0036] In some preferred embodiments, the vitamins per ton of feed, on a dry weight basis, comprise the following components: Vitamin A 5 million IU, Vitamin D 33 million IU, Vitamin E 155g, Vitamin K3 10g, Vitamin B1 6g, Vitamin B2 17g, Vitamin B6 13g, and Vitamin B2. 12 25mg, Vitamin H 88mg, Niacin 45g, Calcium Pantothenate 28g, Folic Acid 2.8g, Inositol 160g, Vitamin C Monophosphate 1150g, and the remainder is defatted rice bran.

[0037] In some embodiments, the minerals per ton of feed, based on dry weight, include the following components: calcium 60-80g, phosphorus 80-100g, potassium 70-90g, magnesium 10-20g, iron 1-3g, zinc 15-20g, copper 2-5g, cobalt 150-180mg, iodine 40-60mg, selenium 3-5mg, with the remainder being a carrier. In some specific embodiments, the carrier is defatted rice bran.

[0038] In some preferred embodiments, the minerals per ton of feed, on a dry weight basis, include the following components: 70g calcium, 90g phosphorus, 80g potassium, 15g magnesium, 1.5g iron, 18g zinc, 3.8g copper, 170mg cobalt, 50mg iodine, 3.9mg selenium, with the remainder being zeolite powder.

[0039] This application provides a method for preparing feed to improve the stress resistance of mud crabs, comprising the following steps:

[0040] Step S1: Mix vitamins, minerals, calcium dihydrogen phosphate, choline chloride, antioxidant BHT, and an anti-stress functional composition to obtain a first mixture; grind Peruvian fish meal, mussel meal, soybean meal, brewer's yeast powder, Antarctic krill powder, and high-gluten flour to obtain a second mixture.

[0041] Step S2: Mix the first mixture with the second mixture and then perform ultra-fine pulverization to obtain the third mixture;

[0042] Step S3: Add deep-sea fish oil, soybean lecithin oil and squid paste to the third mixture, mix evenly, granulate, and then cook and cool to obtain feed.

[0043] In some embodiments, the curing conditions are: maintaining at 100–105°C for 40–50 minutes.

[0044] This application provides an application of feed to improve the stress resistance of mud crabs, which is used to improve the survival rate of mud crabs and / or reduce their stress response.

[0045] The applicant further provides the following specific embodiments to describe the present invention. It should be noted that these embodiments are merely descriptive and do not limit the present invention in any way.

[0046] Example 1

[0047] This embodiment provides a feed that can effectively improve the stress resistance of mud crabs and its preparation method;

[0048] On a dry weight basis, a feed that can effectively improve the stress resistance of mud crabs includes the following components:

[0049] Peruvian fish meal 36%, mussel meal 3%, soybean meal 15%, brewer's yeast powder 5%, Antarctic krill meal 12%, high-gluten flour 18%, deep-sea fish oil 2%, soybean lecithin oil 1%, vitamins 1%, minerals 1%, calcium dihydrogen phosphate 2%, choline chloride 0.3%, squid paste 2%, antioxidant BHT 0.2%, and anti-stress functional composition 1.5%.

[0050] The vitamins in each ton of feed include the following components: Vitamin A 5 million IU, Vitamin D3 3 million IU, Vitamin E 155g, Vitamin K3 10g, Vitamin B1 6g, Vitamin B2 17g, Vitamin B6 13g, and Vitamin B2. 12 25mg, Vitamin H 88mg, Niacin 45g, Calcium Pantothenate 28g, Folic Acid 2.8g, Inositol 160g, Vitamin C Monophosphate 1150g, and the remainder is defatted rice bran.

[0051] The minerals in each ton of feed include the following components: calcium 70g, phosphorus 90g, potassium 80g, magnesium 15g, iron 1.5g, zinc 18g, copper 3.8g, cobalt 170mg, iodine 50mg, selenium 3.9mg, and the remainder is zeolite powder.

[0052] On a dry weight basis, the anti-stress functional composition consists of the following components: 50% L-theanine (Shanghai Yuanye Biotechnology Co., Ltd., catalog number S18118-100g, purity 99%), 20% tea polyphenols (Zhejiang Longsheng Biotechnology Co., Ltd., model LS-TP01, purity ≥98%), 15% Atractylodes macrocephala extract (10:1 ratio extract from Shaanxi Xinyanghe Biotechnology Co., Ltd.), and 15% β-1,3-glucan (Shanghai Aladdin Biochemical Technology Co., Ltd., catalog number A101634, purity ≥95%).

[0053] A method for preparing feed that can effectively improve the stress resistance of mud crabs includes the following steps:

[0054] Step S1, Premixing: Accurately weigh vitamins, minerals, calcium dihydrogen phosphate, choline chloride, antioxidant BHT, and anti-stress functional composition, and mix the above materials evenly in a premixer to obtain the first premix; pulverize the components except for deep-sea fish oil, soybean lecithin oil, and squid paste, namely Peruvian fish meal, mussel meal, soybean meal, brewer's yeast powder, Antarctic krill powder, and high-gluten flour once to obtain the second mixture;

[0055] Step S2: Mix the first mixture and the second mixture evenly, and then pulverize them a second time using an ultrafine pulverizer to obtain the third mixture;

[0056] In step S3, deep-sea fish oil, soybean lecithin oil, and squid paste are added to the third mixture and mixed evenly to obtain the fourth mixture. The fourth mixture is sent to the pelleting silo and passed through a double-layer conditioning machine under steam conditions. Then, the fourth mixture is made into feed pellets with a particle size of 1.5 mm and a length 1 to 2 times the particle size using a pellet mill. The feed pellets are placed in a stabilizing maturation device and kept at 100 to 105°C for 45 minutes. Then, cold air is used to dehydrate and cool the feed pellets. When the temperature of the feed pellets drops to room temperature, the feed that can effectively improve the stress resistance of mud crabs is obtained.

[0057] Example 2

[0058] This embodiment provides a feed that can effectively improve the stress resistance of mud crabs and its preparation method;

[0059] On a dry weight basis, a feed that can effectively improve the stress resistance of mud crabs includes the following components: 34% Peruvian fish meal, 5% mussel meal, 15% soybean meal, 6% brewer's yeast powder, 10% Antarctic krill meal, 18% high-gluten flour, 2% deep-sea fish oil, 1% soybean lecithin oil, 1.5% vitamins, 1.5% minerals, 2% calcium dihydrogen phosphate, 0.3% choline chloride, 2% cuttlefish paste, 0.2% antioxidant BHT, and 1.5% anti-stress functional composition.

[0060] The vitamin content per ton of feed is as follows: Vitamin A 5 million IU, Vitamin D3 3 million IU, Vitamin E 155g, Vitamin K3 10g, Vitamin B1 6g, Vitamin B2 17g, Vitamin B6 13g, Vitamin B... 12 25mg, Vitamin H 88mg, Niacin 45g, Calcium Pantothenate 28g, Folic Acid 2.8g, Inositol 160g, Vitamin C Monophosphate 1150g, and the remainder is defatted rice bran.

[0061] The mineral content per ton of feed is as follows: calcium 70g, phosphorus 90g, potassium 80g, magnesium 15g, iron 1.5g, zinc 18g, copper 3.8g, cobalt 170mg, iodine 50mg, selenium 3.9mg, and the remainder is zeolite powder.

[0062] On a dry weight basis, the anti-stress functional composition consists of the following components: 45% L-theanine, 25% tea polyphenols, 15% Atractylodes macrocephala extract and 15% β-1,3-glucan, manufactured by the same company as in Example 1.

[0063] This comparative example also provides a method for preparing feed that can effectively improve the stress resistance of mud crabs, which is consistent with Example 1.

[0064] Comparative Example 1

[0065] This comparative example provides a feed that can effectively improve the stress resistance of mud crabs. The difference from Example 1 is that L-theanine is replaced with an equal amount of glutamine. Glutamine is a commonly used anti-stress amino acid in aquaculture, which can alleviate osmotic pressure stress and repair the intestinal mucosa, and is widely used in shrimp and crab feed research.

[0066] Comparative Example 2

[0067] This comparative example provides a feed that can effectively improve the stress resistance of mud crabs. The difference from Example 2 is that an equal amount of chlorogenic acid is used instead of tea polyphenols, an equal amount of astragalus extract is used instead of atractylodes extract, and an equal amount of chitosan is used instead of β-1,3-glucan. Chlorogenic acid is a typical representative of plant polyphenols (such as the main active ingredient in honeysuckle extract), widely used in aquaculture stress resistance, and its function overlaps with that of tea polyphenols. Astragalus extract is a commonly used immune-enhancing traditional Chinese medicine in aquaculture, which can increase lysozyme activity, and its "intestinal protection" function, like that of atractylodes extract, falls under the category of traditional Chinese medicine stress resistance. Chitosan, derived from crustaceans, is a commonly used immunopolysaccharide, with a function similar to β-1,3-glucan.

[0068] Application Example 1

[0069] This application was conducted at Raoping Haizenong Marine Biotechnology Co., Ltd. A commercial feed was used as the control group, while Examples 1, 2, Comparative Example 1, and Comparative Example 2 were the experimental groups, with three parallel groups per group and 30 crabs per parallel group, totaling 450 crabs. Healthy crabs of uniform size and initial weight of (15.3±2.4) g were randomly selected and placed in rearing boxes measuring 0.25m×0.40m×0.40m, with one crab per box. Simulated plants were provided inside the boxes for the crabs to hide and inhabit. Environmental conditions (salinity 15 ppt) were maintained during the experiment as in the temporary rearing stage. All rearing boxes were placed under natural light and with continuous ventilation. Crabs were fed to satiety at 8:00 AM and 5:00 PM daily for 30 days. The following tests were conducted during the experiment:

[0070] Growth performance test: At the beginning and end of the feeding trial, all mud crabs were weighed (fasted for 24 hours before weighing), and the weight gain rate and survival rate were calculated using the following formula: Weight gain rate Survival rate In the formula: W0 and W T The initial weight (g) of the mud crabs before rearing and their final weight (g) after 30 days of rearing, respectively; N0 and N T The initial and final numbers of blue crabs are shown in Table 1. The test results are shown in Table 1.

[0071] Stress test: Three stress environments were set up: hypoxia stress, low salinity stress and dry exposure stress. The specific procedures are as follows: (1) Hypoxia stress: 20 mud crabs were randomly selected from 3 parallel groups in each group; air was continuously introduced into the control group to ensure that the dissolved oxygen (DO) content was 7.2±0.3mg / L; the DO content in the experimental group was controlled by adjusting the ratio of nitrogen to air, and the nitrogen and air concentrations were maintained at 1.2±0.3mg / L and 3.4±0.6mg / L, respectively. The DO content was monitored by a dissolved oxygen meter throughout the process and ensured to be stable within the preset range; the survival rate of mud crabs was recorded after 72 hours of hypoxia stress. (2) Low salinity stress: 20 mud crabs were randomly selected from 3 parallel groups in each group, and the salinity of the seawater in the culture box was adjusted to 4ppt; the survival rate of mud crabs was recorded after 72 hours of low salinity stress. (3) Dry dew stress: Twenty mud crabs were randomly selected from the three parallel groups and placed in a constant temperature and humidity chamber. They were subjected to dry dew stress at a temperature of 22℃ and a relative humidity of 70%. The condition of the mud crabs was observed and recorded daily, and the survival rate of the mud crabs was recorded after 72 hours of dry dew stress. All test results of the stress test are summarized in Table 2.

[0072] Table 1. Effects of different feeds on body weight gain and survival rate of mud crabs

[0073]

[0074] Note: Data are expressed as mean ± standard error. Different lowercase letters after the data in the same column indicate significant differences between groups (P<0.05). W0 is the initial body weight; W T W represents final body weight. G SR represents weight gain rate; SR represents survival rate.

[0075] Table 2. Average survival rate of mud crabs fed different diets under various stress conditions

[0076]

[0077] As shown in Tables 1 and 2, the weight gain and survival rate of mud crabs fed with the feed containing the anti-stress functional composition were significantly higher than those of the commercial feed group and the comparative group. Furthermore, stress tests revealed that the survival rate of the example group was significantly higher than that of the commercial feed group and the comparative group. This indicates that the feed provided in this application possesses excellent production performance and stress resistance through the addition of the anti-stress functional composition.

[0078] Comparing Example 1 and Comparative Example 1, it is evident that the L-theanine selected in this formulation, in addition to possessing the basic anti-stress effects of amino acids, can penetrate the blood-brain barrier of blue crabs and exert its effects by regulating the neuroendocrine system and promoting the generation of alpha brain waves. This component, in synergy with tea polyphenols (which have antioxidant properties), Atractylodes macrocephala extract (which can strengthen the spleen and protect the intestines), and β-1,3-glucan (which can activate phagocytes and other immune cells), constructs a three-dimensional regulatory network of "neuro-immune-metabolic". In contrast, Comparative Example 1, which uses glutamine, can only achieve anti-stress effects through the single pathway of "repairing the intestinal mucosa" and cannot form a multi-target synergistic mechanism with the other three components. Therefore, its overall application effect is significantly weaker than that of Example 1.

[0079] Comparing Example 2 and Comparative Example 2, it can be seen that the combination of "tea polyphenols + Atractylodes macrocephala extract" in this scheme has a unique synergistic effect, specifically manifested in two aspects: the flavanols, which account for 75% to 80% of tea polyphenols, can form a complementary effect of "antioxidant + nerve soothing" with L-theanine, while chlorogenic acid in Comparative Example 2 does not have such synergistic properties; Atractylodes macrocephala extract can improve the intestinal digestive function of crabs, and combined with the function of β-1,3-glucan in "activating intestinal immune cells", it forms a "digestive-immune dual protection" system. The Astragalus membranaceus extract used in Comparative Group 2 can only enhance immunity alone, while chitosan is prone to forming a mucosal barrier in the intestine and affecting nutrient absorption. The two cannot form an effective synergy, ultimately resulting in a weaker application effect than Example 2.

[0080] The above are merely preferred embodiments of this application and are not intended to limit the present invention. Although this application has been described in detail with reference to examples, those skilled in the art can still modify the technical solutions described in the foregoing examples or make equivalent substitutions for some of the technical features. However, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A stress resistance functional composition, characterized by, By dry weight, the following components are included in percentages by mass: L-theanine 40% to 50%, tea polyphenols 20% to 30%, atractylodes extract 10% to 15%, and β-1,3-glucan 10% to 15%.

2. Use of the anti-stress functional composition according to claim 1, characterized in that, For preparing a feed or a feed additive.

3. A feed, characterized in that, The anti-stress functional composition of claim 1.

4. A feed for improving the stress resistance of Scylla paramamosain, characterized in that, By dry weight, the following components are included in percentages by mass: Peruvian fish meal 30% to 35%, mussel meal 2% to 4%, soybean meal 12% to 16%, beer yeast meal 2% to 6%, Antarctic krill meal 8% to 12%, high-gluten flour 15% to 20%, deep sea fish oil 1% to 3%, soy lecithin oil 1% to 2%, vitamins 0.5% to 1%, minerals 0.5% to 1%, calcium dihydrogen phosphate 1.5% to 2.5%, choline chloride 0.3% to 0.5%, cuttle paste 1.5% to 2.5%, antioxidant BHT 0.1% to 0.3%, and the anti-stress functional composition of claim 1 1% to 2%.

5. The feed for improving the stress resistance of Scylla paramamosain according to claim 4, characterized in that, The vitamin includes: vitamin A 4-6 million IU, vitamin D 2-4 million IU, vitamin E 100-200 g, vitamin K3 6-15 g, vitamin B1 4-8 g, vitamin B2 10-20 g, vitamin B6 10-15 g, vitamin B12 0.2-0.5 g, vitamin H 70-90 mg, nicotinic acid 40-50 g, calcium pantothenate 25-35 g, folic acid 1-4 g, inositol 100-200 g, VC monophosphate 800-1200 g, and the rest is carrier. 12 20-30 mg, vitamin H 70-90 mg, nicotinic acid 40-50 g, calcium pantothenate 25-35 g, folic acid 1-4 g, inositol 100-200 g, VC monophosphate 800-1200 g, and the rest is carrier.

6. The feed for improving the stress resistance of Scylla paramamosain according to claim 4, characterized in that, Per ton of feed, the minerals include: calcium 60 to 80 g, phosphorus 80 to 100 g, potassium 70 to 90 g, magnesium 10 to 20 g, iron 1 to 3 g, zinc 15 to 20 g, copper 2 to 5 g, cobalt 150 to 180 mg, iodine 40 to 60 mg, selenium 3 to 5 mg, and the balance is a carrier.

7. The feed for improving the stress resistance of Scylla paramamosain according to claim 4, characterized in that, The Peruvian fish meal has a crude protein content of more than 64% by mass; and the soybean meal has a crude protein content of more than 46% by mass.

8. A method for preparing the feed for improving the stress resistance of Scylla paramamosain according to any one of claims 4-7, characterized in that, The method comprises the following steps: Step S1, mixing vitamins, minerals, calcium dihydrogen phosphate, choline chloride, antioxidant BHT, and the anti-stress functional composition of claim 1 to obtain a first mixture; and crushing Peruvian fish meal, mussel meal, soybean meal, beer yeast meal, Antarctic krill meal, and high-gluten flour to obtain a second mixture; Step S2, mixing the first mixture and the second mixture and then performing ultrafine grinding to obtain a third mixture; Step S3, adding deep sea fish oil, soy lecithin oil, and cuttle paste to the third mixture, uniformly mixing, granulating, and then performing aging and cooling to obtain the feed.

9. The method according to claim 8, wherein the feed is prepared by adding the effective amount of the compound to the feed for the Scylla paramamosain. The aging is performed at 100 to 105°C for 40 to 50 min.

10. The use of the feed for improving the stress resistance of Erpobdella punctata according to any one of claims 4 to 7, characterized in that, For improving the survival rate of mud crab and / or reducing the stress response of mud crab. For improving the survival rate of mud crab and / or reducing the stress response of mud crab.

Images