阅读说明：本技术 链壶菌诱抗蛋白质LiiP1的制备方法及应用 (Preparation method and application of streptozochytrium induced resistance protein LiiP1 ) 是由 邱德文 彭智超 王世豪 程远岭 于 2021-07-26 设计创作，主要内容包括：本发明公开了一种链壶菌诱抗蛋白质LiiP1作为饲料添加剂的应用。本发明还公开了一种链壶菌诱抗蛋白质LiiP1的制备方法,包括以下步骤：步骤A、挑取少量链壶菌菌体接种到摇瓶液体培养基中进行种子发酵和振荡培养；步骤B、将种子摇瓶接入发酵罐进行至少2级发酵；步骤C、发酵完成后加入缓冲液保护诱抗蛋白,然后进行破壁；步骤D、将菌体细胞破壁的粗蛋白液中的蛋白酶灭活、粗蛋白液浓缩并添加载体填料助剂,造粒烘干,得到链壶菌诱抗蛋白质。本发明通过从患病大闸蟹体内分离相关真菌并制成相关饲料添加剂颗粒剂,可提升大闸蟹抗病功能,提升其对各种细菌疾病的抵抗能力,减少病害的发生,提高成活率。(The invention discloses an application of streptozochytrium induced resistance protein LiiP1 as a feed additive. The invention also discloses a preparation method of the streptozochytrium induced resistance protein LiiP1, which comprises the following steps: a, selecting a small amount of streptomyces thallus, inoculating the streptomyces thallus into a shake flask liquid culture medium, and performing seed fermentation and shaking culture; b, inoculating the seed shake flask into a fermentation tank for at least 2-stage fermentation; step C, adding a buffer solution to protect the induced protein after fermentation is completed, and then breaking the wall; and D, inactivating protease in the crude protein liquid obtained by breaking the cell walls of the thalli, concentrating the crude protein liquid, adding a carrier filler aid, granulating and drying to obtain the streptozochytrium induced resistance protein. According to the invention, relevant fungi are separated from the bodies of the diseased hairy crabs and prepared into relevant feed additive granules, so that the disease resistance of the hairy crabs can be improved, the resistance of the hairy crabs to various bacterial diseases is improved, the occurrence of diseases is reduced, and the survival rate is improved.)

1. An application of a streptozochytrium induced resistance protein LiiP1 as a feed additive.

2. The use of claim 1, wherein the use is applied to young Yangcheng lake hairy crab seedlings.

3. Use according to claim 2, characterized in that it comprises the following steps:

(1) and inducing the streptochytrium to resist protein LiiP 1: the feed =1: 500-;

(2) feeding the Yangcheng lake hairy crab seedlings by hairy crab feed containing induced resistance protein LiiP1 for 3 times in total, wherein the interval period is 5-7 days each time.

4. A preparation method of a streptozochytrium induced resistance protein LiiP1 is characterized by comprising the following steps:

a, selecting a small amount of streptomyces thallus, inoculating the streptomyces thallus into a shake flask liquid culture medium, and performing seed fermentation and shaking culture;

b, inoculating the seed shake flask into a fermentation tank for at least 2-stage fermentation;

step C, adding 0.5M Tris HCl buffer solution to protect the induced protein after fermentation is finished, and then breaking the wall;

and D, inactivating protease in the crude protein liquid obtained by breaking the cell walls of the thalli, concentrating the crude protein liquid, adding a carrier filler aid, granulating and drying to obtain the streptozochytrium induced resistance protein.

5. The method for preparing the streptozochytrium resistance-inducing protein LiiP1 as claimed in claim 4, wherein the formula of the shake flask liquid culture medium in the step A comprises 4.5-5.5% by mass of yeast powder, 2.5-3.5% by mass of beef extract, 0.5-1.0% by mass of sugar, 0.1-0.2% by mass of ammonium sulfate and the balance of water.

6. The method for preparing the streptozochytrium-induced resistance protein LiiP1 as claimed in claim 4, wherein the step B comprises a 2-stage fermentation, wherein the 1 st stage fermentation comprises the following steps: inoculating the seed into a 50L fermentation tank for fermentation, wherein the liquid loading of the culture medium is 65%, the sterilization temperature is 121 ℃, the fermentation culture temperature is 25-30 ℃, the pH is 6.5-7.0, and the fermentation time is 36 h; the 2 nd stage fermentation comprises the following steps: fermenting the strain in 50L fermentation tank, inoculating into 500L fermentation tank, and fermenting for 25-30h, wherein the liquid loading of culture medium is 70%, the sterilization temperature is 121 deg.C, and the fermentation culture temperature is 25-30 deg.C, and the pH is 6.5-7.0.

7. The method for preparing the streptozochytrium resistance-inducing protein LiiP1 as claimed in claim 6, wherein the formula of the culture medium during the 1 st level fermentation comprises 4.5-5.5 percent of yeast powder, 2.5-3.5 percent of beef extract, 0.5-1.0 percent of sugar, 0.1-0.2 percent of ammonium sulfate and the balance of water in percentage by mass; the formula of the culture medium during the 2 nd level fermentation comprises 4.5-5.5 percent of yeast powder, 2.5-3.5 percent of beef extract, 0.5-1.0 percent of sugar, 0.1-0.2 percent of ammonium sulfate and the balance of water by mass percentage.

8. The method for preparing the streptozochytrium-induced resistance protein LiiP1 as claimed in claim 7, wherein the protein production inducer is added when the OD value of the fermentation liquor is 0.6-0.8 during the 2 nd stage fermentation, and the protein production inducer accounts for 0.05-0.1% of the formula mass of the culture medium.

9. The preparation method of the streptozochytrium-induced resistance protein LiiP1 as claimed in any one of claims 4-8, wherein in the step D, the carrier filler auxiliary agent comprises 35-40 mass percent of corn flour, 15-20 mass percent of dried powder of shells of fishes, shrimps and crabs, 30-35 mass percent of cooked soybean meal, 6-9 mass percent of squid extract and 3-5 mass percent of vitamin complex.

10. The method for preparing the streptozochytrium-induced resistance protein LiiP1 according to any one of claims 4-8, wherein the step D of drying comprises the following steps: concentrating the crude protein liquid by a thin film evaporator, adding a carrier and a filler, fully stirring and uniformly mixing, then granulating by a disc to form small round grains, and finally drying to remove excessive moisture, wherein the drying temperature is 40-50 ℃.

Technical Field

The invention relates to a preparation production process and related application of an induced resistance protein feed additive, in particular to a preparation method of a streptozochytrium induced resistance protein LiiP1 and application of the same as a feed additive in improving the disease resistance and growth promotion of Yangcheng lake hairy crabs.

Background

The resistance-inducing protein feed additive is characterized in that chain chytrid resistance-inducing protein is added into hairy crab feed to improve the disease resistance of hairy crabs and promote the growth of the hairy crabs. At present, the feed for feeding the hairy crabs is generally a foodstuff prepared by fishermen, mainly adopts powder of small fishes and shrimps, lacks a scientific formula, has low content of protein and vitamin in ingredients, is easy to cause the hairy crabs to have insufficient nutrition, slow growth, low immunity and easy disease infection, and has nutrient components in meat quality which do not reach the due standard.

At present, chronic poisoning caused by long-term use of olaquindox in the market, the symptoms of necrosis, congestion, hydrops of abdominal cavity and the like of internal organs of fish are frequently seen, and chromosome aberration and sudden action of animal cells are also found. In 2001, an animal growth promoter quinocetone is introduced in China to replace a olaquindox drug. Practice shows that the feed additive can obviously resist diseases such as hemorrhagic disease, diarrhea and the like and promote the growth of animals after being added into the feed for feeding the livestock, the growth rate can exceed more than 10 percent, but the growth of fishes and shrimps is not as obvious as that of the livestock. In addition, the cost is expensive, which is not suitable for popularization.

No specific medicine for common bacterial diseases of hairy crabs. Farmers have no medicine and can only carry out some physical methods, and the basic measures are to clean pond bottom mud, integrally change water and disinfect the water body by using quick lime, bleaching powder and the like. The medicines are mostly antibiotic products such as sulfonamides, oxytetracycline, nitrofural and the like. The purpose of the antibiotics is mainly to treat bacterial infectious diseases, prevent the bacterial infectious diseases (the using dosage is lower than the therapeutic dosage) and promote the growth of animals as feed additives (the using dosage is 1/10-1/5 of the therapeutic dosage). However, long-term use of antibiotics can induce the emergence of resistant bacteria, and especially long-term use of antibiotics (such as prophylactic dose and growth-promoting dose) with lower than therapeutic dose in hairy crabs can accelerate the emergence of resistant bacteria. Once the drug-resistant bacteria appear and spread in the hairy crabs, the large-scale hairy crabs become a huge drug-resistant gene storage bank. Researches show that the drug-resistant bacteria in the crab meat can be directly or indirectly transferred to eaters and final consumers, namely human beings, and seriously threaten the treatment of human clinical infection.

The low-dose antibiotic residues are often taken by human bodies and gradually accumulated in the bodies to cause the pathological changes of various organs. The effects of antibiotic residues on the body are mainly manifested by allergic reaction, anaphylactic reaction, immunosuppression, teratogenesis, carcinogenesis, mutagenicity, etc., and these operations have serious influence on the quality and environment of hairy crabs.

With the development demands of the industry, breeding manufacturers and feed factories turn eyes to finding green and safe growth promoter feed additives. The first kind is a shell oligosaccharide product, and the product is used as a shrimp and crab feed additive to replace the original shrimp head shell powder, so that the digestion utilization rate of the chitin of the shrimps and crabs can be improved, the growth and development of the shrimps and crabs can be promoted, the immunity can be enhanced, and the survival rate can be improved to a certain extent; the second category is microbial preparation feed additives, which are effective products containing a certain number of microorganisms and their metabolites. The product is widely publicized all the time, and has certain capabilities of promoting growth and improving disease resistance, but the industry can not clearly establish important effective components, can not establish relevant standards, is difficult to realize the industrial production of the effective components, and in addition, a large amount of living microorganisms are released into a water area and are difficult to control the propagation, so that the ecological balance of the water body can be damaged to a certain extent, and the growth of the hairy crabs is influenced.

Recently, the ministry of agriculture in China has clearly shown that the project is to completely forbid the addition of antibiotics in animal feed, and the complete elimination of antibiotic residues in animal products is a necessary trend. The Ministry of agriculture will implement a comprehensive plan for pollution-free food and promote new feed additives.

Therefore, a safe and reliable solution is urgently needed for various diseases and growth-hindering influence factors encountered in the hairy crab culture process, and researches prove that the prevention is mainly carried out and the drug control is assisted, scientific hairy crab culture technology is carried out, a good foodstuff formula is matched, a novel feed additive is used for regulating nutrient elements absorbed by the hairy crabs in the growth process from the young crabs to the adult crabs, so that the autoimmune resistance is improved, and the growth environment of the hairy crabs is maintained.

Disclosure of Invention

The invention aims to provide a preparation method and application of streptozochytrium induced resistance protein LiiP 1. The streptochytrium induced resistance protein LiiP1 can improve the immunity of the hairy crab organism and promote the growth of the hairy crab, and improve the capability of the organism to recognize and eliminate any foreign matters (virus, bacteria and the like) invaded from the outside, treat aged, damaged, dead and denatured self cells and recognize and treat in-vivo mutant cells and virus infected cells.

In order to solve the technical problems, the invention adopts the technical scheme that: an application of a streptozochytrium induced resistance protein LiiP1 as a feed additive.

The invention also provides a preparation method of the streptozochytrium induced resistance protein LiiP1, which comprises the following steps:

a, selecting a small amount of streptomyces thallus, inoculating the streptomyces thallus into a shake flask liquid culture medium, and performing seed fermentation and shaking culture;

b, inoculating the seed shake flask into a fermentation tank for at least 2-stage fermentation;

step C, adding 0.5M Tris HCl buffer solution to protect the induced protein after fermentation is finished, and then breaking the wall;

and D, inactivating protease in the crude protein liquid obtained by breaking the cell walls of the thalli, concentrating the crude protein liquid, adding a carrier filler aid, granulating and drying to obtain the streptozochytrium induced resistance protein.

The action mechanism of the invention is as follows: the lipo-resistance-inducing protein LiiP1 can be extracted from the streptochytrium through the preparation method of the lipo-resistance-inducing protein LiiP1 of the streptochytrium. The hairy crab belongs to the arthropod Crustacea, has low evolution degree and simple immune system, and the streptochytrium induced anti-protein is transported to the midgut through the cardia stomach and the pylorus stomach by utilizing the characteristic that the streptochytrium induced anti-protein is very stable within the range of pH 4-11 after being taken by the hairy crab to be ingested into the body, and then is contacted with the body fluid of the hairy crab, thereby stimulating the humoral immunity factor of the hairy crab, improving the expression of superoxide dismutase POD, inducing the superoxide dismutase POD to generate various bioactive molecules, such as antibacterial factors, cell activating factors, lysozyme and the like, improving the antibacterial capability of the hairy crab and promoting the feeding of the hairy crab. According to the preparation method disclosed by the invention, other chain chytrid metabolites such as various vitamins, amino acids and chelated trace elements can be obtained while the LiiP1 is prepared, so that nutrition can be better provided for the hairy crabs affected by the induced resistance protein LiiP1 on the basis of the traditional feed, the growth of the hairy crabs is promoted, and the crab meat quality is improved.

The invention has the beneficial effects that: 1. 2, the streptochytrium induced resistance protein LiiP1 can promote the disease resistance and growth promotion of Yangcheng lake hairy crabs after the hairy crabs are fed with the feed, can effectively promote the disease resistance and growth promotion of the hairy crabs in the clearing lake, and is efficient, healthy and environment-friendly; 3. the resistance-inducing protein is a product produced by fermentation in bioengineering, is rich in vitamins, amino acids and chelated trace elements necessary for aquatic animals besides effective components, can supplement the deficiency of the nutritional components of the feed, improve the utilization rate of the feed, improve the taste of the feed, improve the palatability of the feed, promote the normal development and rapid growth of the aquatic animals, and can induce the resistance of the immune system of the live fresh water crabs after the resistance-inducing protein enters the bodies of the live fresh water crabs, thereby enhancing the disease resistance, and simultaneously, the resistance-inducing protein can secrete digestive enzymes to improve the digestive absorption rate of feed raw materials by passing through the immune system of the live fresh water crabs, thereby enhancing the nutritional value of the feed and promoting the growth; 4. the preparation process realizes industrial production, can obtain a large amount of active ingredient resistance-inducing protein through efficient propagation of the streptozochytrium, reduces the production cost, does not generate three wastes in the whole production process, and belongs to an environment-friendly process.

The present invention will be described in detail with reference to the accompanying drawings.

Drawings

FIG. 1 is a flow chart of a method for preparing the streptozochytrium-induced resistance protein LiiP1 in the invention;

FIG. 2 is a graph comparing the superoxide dismutase (SOD) activity of example 1 in the second application of the streptozochytrium-induced resistance protein LiiP1 of the present invention;

FIG. 3 is a comparison graph of the meat nutrient content of hairy crabs in example 1 in the second application of the chain chytrid resistance-inducing protein LiiP1 of the invention.

Detailed Description

Referring to the attached figure 1, the invention also provides a preparation method of the streptozochytrium resistance-inducing protein LiiP1, which comprises the following steps.

And step A, selecting a small amount of thalli, inoculating the selected thalli into a shake flask liquid culture medium, and performing seed fermentation and shaking culture.

In detail, the formula of the shake flask liquid culture medium in the step comprises, by mass, 4.5-5.5 parts of yeast powder, 2.5-3.5 parts of beef extract, 0.5-1.0 part of sugar, 0.1-0.2 part of ammonium sulfate and the balance of water. The shaking culture condition is that shaking culture is carried out at 180rpm-200rpm and 25-30 deg.C for at least 40 h.

And step B, inoculating the shake flask of the seeds into a fermentation tank for at least 2-stage fermentation.

The stage 1 fermentation comprises the following steps: inoculating the seed into a 50L fermentation tank for fermentation, wherein the liquid loading of the culture medium is 65%, the sterilization temperature is 121 ℃, the fermentation culture temperature is 25-30 ℃, the pH is 6.5-7.0, and the fermentation time is 36 h; the 2 nd stage fermentation comprises the following steps: fermenting the strain in 50L fermentation tank, inoculating into 500L fermentation tank, and fermenting, wherein the liquid loading of culture medium is 70%, the sterilization temperature is 121 deg.C, the fermentation culture temperature is 25-30 deg.C, the pH is 6.5-7.0, and the fermentation time is 25-30h (preferably 25 h).

The formula of the culture medium during the 1 st level fermentation comprises, by mass, 4.5-5.5 parts of yeast powder, 2.5-3.5 parts of beef extract, 0.5-1.0 part of sugar, 0.1-0.2 part of ammonium sulfate and the balance of water.

The formula of the culture medium during the 2 nd level fermentation comprises 4.5-5.5 percent of yeast powder, 2.5-3.5 percent of beef extract, 0.5-1.0 percent of sugar, 0.1-0.2 percent of ammonium sulfate and the balance of water by mass percentage. When the 2 nd stage fermentation is carried out, adding protein production inducer when the OD value of the fermentation liquor is 0.6-0.8 (the mass of the added protein production inducer accounts for 0.05-0.1% of the mass of the formula of the culture medium).

The protein production inducer can be IPTG, lactose, pyruvic acid or their combination.

If large-scale fermentation is needed, 3-stage fermentation can be carried out.

And step C, adding 0.5M Tris HCl buffer solution to protect induced resistance protein after fermentation is finished, and then breaking the wall.

And D, inactivating protease in the crude protein liquid obtained by breaking the cell walls of the thalli, concentrating the crude protein liquid, adding a carrier filler aid, granulating and drying. In detail, the crude protein liquid is heated to 90 ℃ to denature and inactivate protease, then concentrated in a film evaporator, added with a carrier and a filler, fully stirred and uniformly mixed, then made into small round granules with the diameter of 3mm by a disc granulator, and finally properly dried to remove excessive moisture. The drying temperature is 40-50 ℃.

The invention also provides an application of the streptozochytrium induced resistance protein LiiP1 as a feed additive, in particular to the application of the streptozochytrium induced resistance protein LiiP1 in the Yangcheng lake hairy crab seedling body so as to improve the disease resistance of the hairy crab and promote the growth capability of the hairy crab. The above-mentioned streptozochytrium resistance-inducing protein additive refers to adding the resistance-inducing protein separated by culturing streptozochytrium into live fresh crab feed. The specific application steps are as follows.

(1) And inducing the streptochytrium to resist protein LiiP 1: the feed =1: 500-.

(2) Feeding hairy crab seedlings in Yangcheng lake with hairy crab feed containing induced resistance protein for 3 times, wherein the interval period is 5-7 days.

The application one is as follows: the disease resistance of the hairy crab seedling bodies is improved through feeding treatment, and the survival rate is improved.

The hairy crab seedling body is treated with feed to raise disease resistance, and the method includes the following steps:

(1) and culturing and separating induced resistance protein in the streptozochytrium, wherein the induced resistance protein comprises the following components: the feed is added into the hairy crab feed in a proportion of 1:500 and 1000 times; (ii) a

(2) And feeding the Yangcheng lake hairy crab seedlings by using hairy crab feed containing resistance-inducing protein, wherein the feeding is carried out once a day and 3 times in total, and the interval period is 5-7 days.

The feed feeding treatment containing the resistance-inducing protein feed additive can be applied in the whole growth period of the hairy crabs, but the feeding treatment effect on the hairy crab seedling bodies is better through our observation and long-term research, and the hairy crab seedling bodies are preferably 80-120 seedlings/jin.

Example 1: adding induced-resistance protein separated by culturing in the streptochytrium in the hairy crab feed according to the proportion of 1: 500-; feeding hairy crab in Yangcheng lake with hairy crab feed containing induced resistance protein, and using common feed as control, wherein each treatment uses 50 crabs. After the feed is fed for 120 hours, pathogenic bacteria are added into the feeding groove, the number of remained live crabs is counted respectively after the pathogenic bacteria are added for 24 hours, 48 hours, 72 hours and 96 hours, and the experimental results after treatment are shown in the following table:

wherein, immune protection rate = (control mortality-immune mortality)/control mortality.

Results and analysis: as can be seen from the above table, the chain pot induced resistance protein can obviously enhance the disease resistance of the hairy crabs, the hairy crabs treated by the method can show obvious disease resistance when being invaded by related pathogenic bacteria, and the immune protection rate reaches 65%.

The application II comprises the following steps: the disease resistance of the hairy crabs can be improved by feeding the hairy crabs with the feed additive of the chain chytrid induced resistance protein LiiP 1.

Furthermore, the disease resistance of the hairy crabs can be improved by feeding the hairy crabs with the feed additive containing the chain chytrid inducing and resisting protein LiiP1, the feeding time is at least 3-4 days ahead of the epidemic disease high-incidence period, 2 times of feeding are carried out every day for 6 times, and the ratio of the chain chytrid inducing and resisting protein additive to the bait is 1-500: 1000 (1: 1000 in this example). The feeding treatment can also be applied in the whole growth period of the hairy crabs, but the effect is better when the feeding treatment is used before corresponding diseases occur in peripheral areas through observation and long-term research.

The feed containing the streptochytrium streptozochytrium induced resistance protein LiiP1 feed additive has the effect of improving the disease resistance of hairy crabs when fed to the hairy crabs, and researches show that serum lysozyme and superoxide dismutase (SOD) of the hairy crabs in Yangcheng lake are increased within a certain time after the feed additive containing the streptochytrium streptozochytrium induced resistance protein LiiP1 is fed to the hairy crabs, and meanwhile, the measured immune protection rate is 64 percent, which proves that the disease resistance of the hairy crabs in Yangcheng lake can be enhanced by feeding the streptochytrium induced resistance protein. Phagocytosis plays an important role in immune defense of crustaceans, and before, during and after phagocytosis, various antioxidant enzymes, oxidase and hydrolase play important roles, wherein the key antioxidant enzymes mainly comprise superoxide dismutase (SOD), catalase, peroxidase and the like, and SOD is one of the key antioxidant enzymes, is a natural scavenging agent of superoxide radical, can scavenge redundant free radicals in vivo, and enables the formation and the scavenging of the free radicals to be in dynamic balance, so that the damage to biological molecules and the like are avoided. Therefore, SOD can be used as the non-specific immunity index of the organism to judge the influence of the immunostimulant on the non-specific immunity of the organism.

Example 1: feeding the streptochytrium induced resistance protein LiiP1 feed additive through mixed feed, and further detecting serum SOD activity of the hairy crabs and detecting disease resistance of the hairy crabs.

The healthy Yangcheng lake hairy crab is transferred to a pond river crab farm with the specification of about 50g, the healthy Yangcheng lake hairy crab is raised in an aquarium with the length of 120cm by 80cm in a laboratory, a proper amount of waterweeds, tiles and the like are put in the aquarium, 15 crabs are put in each aquarium, and each group of three aquariums are provided; the experiment was started after one week of temporary rearing at a water temperature of 25-28 ℃. 09:00 and 16 per day: 30 times of feeding respectively, wherein the feeding amount is about 3 percent of the crab weight (the protein content is 3 percent) and the feeding is continuously carried out for 3 days. Control with normal feed, 50 crabs were used for each treatment. After 3 days of feeding, a large number of pathogenic bacteria are added into the aquarium, and after 24 hours, 48 hours, 72 hours and 96 hours of pathogenic bacteria are added, the experimental results after counting the number of the remained live crabs are shown in the following table:

。

preparation of serum the hairy crab fed with common feed and fed with streptochytrium induced resistance protein 12, 24, 36, 48, 72, 96, 120 and 144h are respectively taken, the haemolymph is taken out by breaking off from the second joint, the hairy crab is placed in an Eppendorf centrifuge tube overnight at 4 ℃, and then the low-speed centrifugation is carried out to separate out the serum.

The determination of the SOD activity of superoxide dismutase is carried out according to a pyrogallol autoxidation method of Dengdubiyu and the like. As shown in fig. 2, superoxide dismutase (SOD) activity: after the hairy crabs are fed with the feed of the streptochytrium induced resistance protein LiiP1 feed additive, the activities of superoxide dismutase (SOD) sampled at different times are respectively 117 (12 h), 163 (24 h), 211 (36 h), 244 (48 h), 263 (72 h), 251 (96 h), 218 (120 h) and 176 (144 h), and the average value of a control group is 114.5. The activity of superoxide dismutase (SOD) gradually increases along with the duration of the immunization, reaches the maximum at 72h and then gradually decreases, and the difference is obvious by a t test (P < 0.05).

The application is as follows: the hairy crab is fed with the feed containing the chain chytrid induced resistance protein LiiP1 feed additive, so that the growth of the hairy crab can be promoted, the market time of the hairy crab can be advanced, and the meat quality can be improved.

Example 1 feeding the streptozochytrium induced resistance protein LiiP1 feed additive into the hairy crab feed according to the proportion of 1: 500-. As shown in figure 3, 100 young crabs in the same batch are taken, 50 hairy crabs are fed with mixed feed of a test group induced resistance protein additive and a common feed of a control group, the test period is the whole breeding period of the hairy crabs, the nutritional components of the meat part of the hairy crabs are measured according to the national method for measuring the nutritional components of the meat of the hairy crabs, the obtained average value is shown in figure 3, and the result obtained by comparison shows that the streptochytrium induced resistance protein has obvious effect of improving the nutritional components of the meat of the hairy crabs, improves the quality of the hairy crabs and has better economic value.

From larval crabs to adult crabs, the crabs can reach the market standard after five molting, and the crabs can double and grow after each molting, so that the growth and molting of the hairy crabs are accelerated to promote growth, so that how to promote the growth and molting of the crabs, the crabs are mature in advance, come into the market in advance, and obtain high return, the problems need to be solved in the feeding process in the growth process. The experimental group uses the protein additive feed for feeding, the control group uses the common feed, the experimental group randomly detects 500 male crabs and female crabs from the same batch of hairy crabs, the control group detects 500 male crabs and female crabs, the following table shows is obtained, and the result comparison shows that the streptochytrium antimicrobial protein inducing feed additive can effectively promote the growth of the hairy crabs, and the streptochytrium antimicrobial protein inducing feed additive can bring good economic value to crab farmers because the market values of the hairy crabs with different specifications are greatly different.

。

The technical scheme mainly lists the application of young crabs and adult crabs in the treatment of hairy crab resistance diseases, but experiments and observations show that the streptozochytrium induced resistance protein has obvious effects on improving the stress capability of the hairy crabs, improving the adverse environment capability of the hairy crabs and improving the survival rate of the hairy crabs, and has obvious effects on promoting the growth speed of the hairy crabs and improving the quality. Therefore, the streptozochytrium induced resistance protein LiiP1 feed additive has universality in improving the response of the hairy crabs to other diseases and promoting growth, and is a good disease resistance feed additive for Yangcheng lake hairy crabs with great application potential and research value.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.