163 results about "Chinese softshell turtle" patented technology

The invention relates to a method for comprehensively raising various types of aquatic livestock and cultivating paddy in a paddy field, in particular to the raising of Chinese soft-shelled turtles, crawfish and carassius auratus gibelio in the paddy field and the cultivation of paddy. The method comprises the steps of paddy field preparation, aquatic plant transplantation, live food feeding, paddy transplantation, young aquatic livestock placement, bait feeding, daily management, aquatic livestock fishing and paddy harvest. The method for comprehensively raising various types of aquatic livestock and cultivating paddy in the paddy field has the advantages that the various types of aquatic livestock can be raised and paddy can be cultivated in the same field comprehensively, the difference between the period for paddy cultivation and the period for raising aquatic livestock is small, the use rate and the comprehensive efficiency of the field can be effectively improved, and economic benefit can be improved to a large extent; meanwhile, any chemical fertilizer, herbicide and insecticide are not used in the process of production, the produced products can meet the standard of organic food, and finally, edible safety of the products is achieved; the whole process of production is beneficial to conservation of water and soil of the field and the surrounding environment and effectively facilitates the protection of natural ecology.

An ecological method for culturing the turtles in large scale without environmental pollution includes such steps as choosing an ecological culture environment, preparation, culturing, feeding forage, and preventing and treating diseases.

A composite feed for culturing Chinese turtles without environmental pollution is proportionally prepared from fish powder, milk powder, glutelin powder, egg yolk powder, starch, yeast, puffed soybean and trace elements.

The invention relates to a device and method for hatching the embryos of Chinese softshell turtles. The device comprises an incubator, an incubation plate and a collecting box and is characterized by further comprising a temperature sensor, a humidity sensor, a temperature control device, a humidifying device and a ventilation device. After the device is adopted, fertile eggs can be automatically hatched in a completely naked state; the device is high in hatching efficiency; and the defects that the fertile eggs are mildewed, the embryos die and the like caused by medium incubation in the prior art can be avoided.

The invention discloses a new Chinese softshell turtle breeding method. The formula of feed for Chinese softshell turtles comprises 40-60% of sawdust, 5-15% of yellow soil, 15-25% of vegetable garden soil, 10-15% of briquette slag, 2-5% of bone meal and 5-10% of groundnut meal. The feed for Chinese softshell turtles is prepared by the following steps: firstly disinfecting and fermenting the sawdust: sieving clean and non-toxic sawdust and adding water to ferment the sawdust; then, sieving and crushing the auxiliary materials: sieving and crushing the clean and non-toxic vegetable garden soil, yellow soil and burnt briquette slag, mixing the feed soil and piling up, uniformly mixing the six raw materials according to the formula of the feed, adding clear water and stirring till the moisture reaches a level that a kneaded mixture ball is scattered once falling down to the ground; and finally pilling up for one week, thus obtaining the feed soil for Chinese softshell turtles. The feed soil for Chinese softshell turtles has the advantages that the Chinese softshell turtle fed with the feed soil is short in growth cycle and strong in disease resistance and can grow quickly; the cost is low and the yield is high; particularly, the growth cycle of the Chinese softshell turtle fed with the feed soil is shortened to 6-8months from 30-month growth cycle of a wild Chinese softshell turtle and the yield is improved by about 30%.

The invention provides a method for preventing and controlling rice grubs by breeding soft-shelled turtle in a rice field, comprising the following steps of: (1) breeding strong rice seedlings, and transplanting the rice seedlings to large field; (2) digging deep ditches at the periphery and the middle part of the rice field; (3) setting habitats for the soft-shelled turtle at the middle part of the rice field and at the two sides of the rice field; (4) mounting escaping (stealing)-preventing facilities; (5) selecting young soft-shelled turtles; and (6) determining breeding time and density of soft-shelled turtle and disinfecting the young soft-shelled turtles, wherein Chinese soft-shelled turtle can be bred two days after rice is transplanted, and 30-50 Chinese soft-shelled turtles with the weight of 250-300g can be bred every 667 square meters. By adopting the method provided by the invention, quantity of spiders in the rice field can be improved, the quantity of rice plant hoppers can be reduced, ratio of the spiders to the rice plant hoppers is improved by 45.23%, damage of the rice plant hoppers is obviously reduced, control effect on cnaphalocrocis medinalis is 38.89%, and dead heart rate caused by damage of borers (chilo suppressalis and sesamia inferens) is reduced by 25% compared with that of the rice field in which the soft-shelled turtles are not bred.

The invention discloses a cultivation and breeding method of improved-variety Chinese soft-shelled turtles. The method comprises the steps of introduction of Yellow River soft-shelled turtles and Japanese soft-shelled turtles of superior species, cultivation of improved-varieties parent soft-shelled turtles of each species, hybridization of excellent parents, protection of the improved varieties, and artificial incubation. The method has the advantages of operability, consistent parent estrus time, high fertilization rate, high spawning rate and high incubation rate. Moreover, the cultivated improved-variety Chinese soft-shelled turtle offsprings are high in quality and nutritional value, and are comparable to wild soft-shelled turtles in eating mouthfeel, color and luster. As proved by market, the improved-variety Chinese soft-shelled turtles are recognized by consumers.

The invention relates to a PCR amplification primer and a method for rapidly identifying a genetic sex of Chinese softshell turtle. A sequence of the primer is as shown by SEQ ID No.1 and SEQ ID No. 2. The identification method adopts Chinese softshell turtle DNA to be identified as a template and utilizes the primer to perform PCR amplification, the electrophoresis detection is performed for an amplification product, when the amplification product has a strip of 973bp, identifying the genetic sex of the individual Chinese softshell turtle as the female (i.e. the type of sex chromosome is ZZ);and when the amplification product has the strip of 1533bp and the strip of 973bp, identifying the genetic sex of the individual Chinese softshell turtle as the male (i.e. the type of the sex chromosome is ZW). The invention also provides a kit comprising the primer. The PCR amplification primer, the method and the kit are simple, rapid, low in cost, and capable of providing reference evidence for developing a Chinese softshell turtle genetic sex marker, identifying the genetic sex, studying the sex decision mechanism and studying the artificially-controlled Chinese softshell turtle sex differentiation.

The invention discloses a method for integrated culture of rice-finless eel-crayfishp-trionyx sinensis. The method comprises the following steps: placing myriophyllum aquaticum in a ring-shaped ditchof a paddy field; putting crayfish seedlings in April or August, putting trionyx sinensis seedlings and cipangopaludina cahayensis in May, and putting finless eel seedlings in late June to early July;performing feeding; and catching crayfish in early June or early October, and catching finless eels and trionyx sinensis in November to December. According to the method for integrated culture of therice-finless eel-crayfish-trionyx sinensis, ecosystem biodiversity of the paddy field is improved, cannibalism degree of the crayfish is reduced, requirement for live baits of the finless eels and the trionyx sinensis is satisfied; and the method has the advantages of higher biological diversity, easy catching, adequate supply of live baits, more stable culture yields, higher economic benefits, and the likes.

The invention discloses a PCR (Polymerase Chain Reaction) amplification primer for quickly distinguishing the genetic sex of a Chinese softshell turtle. The PCR amplification primer comprises a pair of sex specificity molecular markers and a pair of reference gene primers. The invention further discloses a PCR method for quickly distinguishing the genetic sex of the Chinese softshell turtle and akit for quickly distinguishing the genetic sex of the Chinese softshell turtle. The amplification primer can distinguish the genetic sex of the Chinese softshell turtle in the early stage. The methodis low in cost and easy and convenient to operate and can quickly distinguish a large batch of turtles, and a result is intuitive and accurate.

The invention discloses a Chinese-herbal-medicine feed additive capable of improving the meat quality of a Chinese softshell turtle and a feed containing the additive. The Chinese-herbal-medicine feed additive is prepared by taking rhizoma atractylodis macrocephalae, angelica sinensis, rehmannia glutinosa, fennel, hawthorn, pericarpium citri reticulatae, eucommia ulmoides, medicated leaven, malt, poria cocos, codonopsis pilosula, cinnamon, purple perilla and polygonum multiflorum as materials through the steps of drying, crushing and mixing uniformly according to certain proportion. After the Chinese-herbal-medicine feed additive is added into the feed of the Chinese softshell turtle, the meat quality of the Chinese softshell turtle can be improved, the growth can be promoted and the immunity can be improved; the Chinese-herbal-medicine feed additive has the advantages of no pollution, no medicine resistance, no residue and the like, is wide in source, low in price and convenient to manufacture, can greatly reduce the culture cost of the Chinese softshell turtle, and is suitable for industrial production, thus being a green and environment-friendly feed additive.

The present invention discloses a whole-course pollution-free and ecological cultivation method for Chinese softshell turtles. The cultivation method comprises the following steps of: temporarily cultivating juvenile turtles; building a intensive cultivating tank for the juvenile turtles in an pond outside; stocking the juvenile turtles; respectively feeding the juvenile turtles; water quality management; overwintering management; and disease prevention. According to the whole-course pollution-free and ecological cultivation method for Chinese softshell turtles disclosed in the present invention, hatching juvenile turtles; after temporarily cultivation of the juvenile turtles, stocking the juvenile turtles into an outside pool simulating living environment of turtles in the nature; cultivating turtles in different stages in the pool outside for three years or more with scientific released density; in the whole cultivation process, water quality remaining good without any pollution and uses of forbidden drugs, as well feed that is balanced in nutrition proportion without any forbidden additives is used, with fresh and live baits as auxiliary feed; accordingly, pollution-free turtles with good quality and commercial specification being over 1.5 kg each turtle are cultivated; and the cultivated turtles are high in nutrition and medical value.

The present invention relates to the technical field of aquatic feeds and particularly relates to powdery compound feed for a young Chinese softshell turtle stage and a production and processing device. The powdery compound feed comprises a box body, wherein the box body is provided with a cover plate, the cover plate is provided with a crushing structure and a stirring structure, the stirring structure comprises a driving motor, a first bevel gear, a first rotating rod, a stirring plate and second bevel gears. the box body is evenly and fixedly connected with shaking structures used for shaking filter plates in the circumferential direction below the filter plates, the box body is provided with a circulating structure, and a quantitative discharging structure used for quantitative discharging is arranged at the bottom of the box body. Crushing, stirring, circulating structures and screening are driven by a set of driving motors, so that use of electrical equipment is reduced, and theuse cost is reduced.

The invention relates to a Chinese medicinal herb feed additive for regulating the fat metabolism of a Chinese softshell turtle, promoting growth and enhancing immunity and a feed containing the same. The Chinese medicinal herb feed additive is prepared from cassia seeds, fructus hordei germinatus, hawthorns, lotus leaves, medicated leaven and radix paeoniae alba by the steps of drying, crushing and uniformly mixing. After being added to the common feed of the Chinese softshell turtle, the Chinese medicinal herb feed additive disclosed by the invention can outstandingly increase the growth speed of the Chinese softshell turtle, promote the fat metabolism of an organism and enhance the nonspecific immunity capacity of the Chinese softshell turtle, outstandingly enhance the T-SOD (Total Superoxide Dismutase) and LSZ (Lysozyme) activity of serums and outstandingly reduce the LDH (Lactate Dehydrogenase) activity and the content of MDA (Methane Dicarboxylic Aldehyde), TG (Triglyceride), TC (Total Cholesterol) and LDL-C (Low-Density Lipoprotein Cholesterol). The Chinese medicinal herb feed additive is environment-friendly, natural, does not generate drug fast or residues, has multiple functions as well as characteristics such as growth consideration and fatty liver resistance, can greatly improve the survival rate of the Chinese softshell turtle and reduce the culture cost of the Chinese softshell turtle and is suitable for industrialized production.

The invention relates to a probiotic feed additive for Chinese softshell turtles and a preparation method of the probiotic feed additive. The probiotic feed additive is prepared from probiotics and carrier fillers, wherein the carrier fillers are sterilized wheat bran, and the probiotics include bacillus subtilis, bacillus natto, Lactobacillus casei and candida utilis with the ratio of (0.4-0.6):(0.4-0.6):(0.8-1.2):(0.8-1.2), and the probiotics are added in the aseptic carrier fillers to prepare probiotic powder. The probiotic feed additive can improve the growth performance of the Chinese softshell turtles, reduce the food coefficient, improve the immunological function and reduce the diseases, has the advantages of low cost, no pollution, no drug resistance, no residue and the like, and is environmentally friendly.

The invention discloses a sex control method for Chinese soft-shelled turtles, which includes: firstly, controlling the incubation temperature to be from 23 DEG C to 35 DEG C; and secondly, dropwise adding methyltestosterone to an animal pole of each fertilized egg. By means of temperature control and application of the methyltestosterone, the sex control method evidently increases a male proportion of Chinese soft-shelled turtles and meets market requirements.

The invention discloses a cultivation method for cultivating Chinese softshell turtles and yellow-head catfish meats. The method comprises the following steps: (1) draining water in a tank and exposing to sun, sterilizing by uniformly scattering calcined lime for sterilization, applying fermented organic manure after 2-3 days, and equipping an aerator; (2) breeding yellow-head catfish meat fingerlings which are 2-3cm per fish, and Chinese softshell turtle fingerlings which are 0.25-0.5kg per fish, regulating the amount of fodders once every 7-10h, and adding vitamins and / or saccharomycetes which take up to 5-10% of fodders in the fodders every 10-15 days; (4) after 7 days of breeding the fingerlings, spraying trichodina once, filling fresh water every 7-10 day once, and keeping the transparency of the cultivation water to be greater than 30cm; and (5) fishing once every 1-3 months. The healthy cultivation method for cultivating Chinese softshell turtles and yellow-head catfish meats with high efficiency is used for cultivating, so as to reasonably determine the breeding specification and cultivation density, improve the utilization factors of the tank water, control the cultivation risk, improve the comparative benefit of pond culture, therefore, the biological healthful aquaculture of cultivating Chinese softshell turtles and yellow-head catfish meats can be realized.

The invention discloses a method for managing pond aquaculture of Chinese softshell turtles, and relates to the technical field of transformations of aquaculture technologies. The method is characterized by comprising the following steps: selecting pond conditions, making a back drying table, making a feed table, stocking young Chinese softshell turtles, throwing feed for breeding, and managing the water quality. The method is reasonable, convenient to operate and clear in proportion.

The invention belongs to the technical field of aquatic product biology and discloses a molecular marker for genetic sex identification of Chinese soft-shell turtles and a method. The method comprisesthe steps: sequencing male and female individuals of the Chinese soft-shell turtles by adopting a RAD technology, and screening male and female specific fragments; carrying out female genome Walkingaccording to the male and female specific fragments, so as to obtain a specific fragment SEQ ID NO: 1 of 6532bp; designing primers on the basis of the specific fragment, and carrying out primer screening and verification, so as to obtain specific primers; acquiring calipash tissue of the Chinese soft-shell turtles, extracting genomic DNA from the Chinese soft-shell turtles, and carrying out amplification on Chinese soft-shell turtle individuals by using primer pairs; subjecting an amplification result to cataphoresis detection; carrying out genetic sex identification. According to the molecular marker and the method, the problem that gender-specific markers of the Chinese soft-shell turtles are not applied to genetic sex identification yet at present is solved, and thus, the molecular marker and the method are original. The success rate of accurate identification reaches 100%.

The invention discloses a hatching device and method for Chinese softshell turtle eggs. The hatching device comprises a hatching house controller and a water tank, and a heater is arranged in the water tank; more uniform heating or cooling is achieved through floor heating and hot air or cold air blowing in an air duct of the side wall of a hatching house; the temperature and the humidity in the hatching house are changed and adjusted by detecting the temperature and the humidity in the hatching house in real time and comparing detected temperature values and detected humidity values with a preset temperature value and a preset humidity value, therefore, it is guaranteed that the temperature and the humidity in the hatching house are within the preset ranges, softshell turtle egg hatching and control over the male and female of hatched Chinese softshell turtles are guaranteed, the hatching rate is increased, and the hatching time is shortened.

The invention discloses a feed additive for trionyx sinensis and a preparation method of the feed additive. For specific conditions of the trionyx sinensis, the feed additive is prepared through combination of modern bioprocesses according to a certain rule and on the basis of the theory of traditional Chinese herbal medicines, is nature in sources, can effectively increase the nutritional value of a basic feed, improve immunity of the trionyx sinensis, guarantee health of the trionyx sinensis, remarkably improve the flavor and nutritional value of the trionyx sinensis, take effects quickly, and greatly improve the quality of the trionyx sinensis within two months. In addition, the living bacterium additive is long in guarantee period and can be stored for 18 months at normal temperature with, and the living bacterium survival rate can still reach 90% or above.

The invention relates to a collagen extracting method, in particular to an ultrasonic auxiliary acid extracting method for optimizing collagen through a response surface method. The method includes the steps of conducting chopping and impurity removal processing on fresh or frozen Chinese softshell turtle outskirts, adding an acetic acid solution with concentration of 0.3-0.6 mol / L to an impurity-removed sample according to the material-liquid ratio of 1:(10-30), putting the materials into an ultrasonic reactor for intermittent ultrasonic extraction in the mode that ultrasonic processing is conducted for the first preset time and the intermitting processing is conducted for the second preset time repeatedly, taking supernate after centrifuging, adding NaCl to the supernate, conducting filtering after standing and salting out, redissolving protein precipitates with acetic acid with the same concentration, sequentially dialyzing acetic acid and distilled water, and finally conducting freeze-drying to obtain a sample, wherein the first preset time is shorter than or equal to the second preset time. The method is high in extracting efficiency, high in collagen solubility and high in raw material utilization value and collagen utilization rate.

The invention discloses a low-fish-meal-content compound pellet feed for young Chinese soft-shell turtles and a preparation method and belongs to the field of feed. The low-fish-meal-content compound pellet feed is prepared from, by weight, fish meal 30-35%, fermented soybean meal 12-17%, soybean protein concentrate 12-17%, corn protein powder 2-3%, gelatinized starch 20-22%, a compound animal-derived nutritional feed attractant 6-12%, mixed oil 1.5-3.0%, coated methionine 0.1-0.3%, choline chloride 0.1-0.3%, calcium dihydrogen phosphate 0.8-1.2%, vitamin premix 0.3-0.5%, mineral premix 0.3-0.5% and phytase 0.01-0.02%. The low-fish-meal-content compound pellet feed is comprehensive and balanced in nutrition and meets the nutrition demands of the young Chinese soft-shell turtles. Compared with current commercially available commodity feed for the young Chinese soft-shell turtles, the production cost is remarkably reduced, breeding effect is good, and feed coefficient is low.

The invention relates to the technical field of a preparation method for antihypertensive peptide, in particular to a method for preparing antihypertensive peptide through Chinese softshell turtles by means of mixed enzymolysis and film filtration. The method mainly comprises the key steps of raw material preprocessing, mixed enzyme hydrolysis, enzyme deactivation, centrifugal filtration, film filtration, freeze-drying and the like. Mixed enzyme in the mixed enzyme hydrolysis is prepared from, by mass, 39-44% of papain, 28-33% of neutral protease and 24-28% of trypsin. The mixed enzyme hydrolysis method is adopted for preparation, the enzyme utilization rate is high, the conversion rate and the inhibition rate of the Chinese softshell turtle antihypertensive peptide are both high, mixed enzyme hydrolysis and film filtration can be continuously conducted, continuous operation is achieved, industrial production is conducted easily, and the production efficiency is improved.

A family individual fluorescence marking method of improved variety breeding of Chinese softshell turtle is provided, belonging to the aquaculture technical field, comprising the steps of marking individual of each family young turtle which is just batched, injecting a marking liquid mixed by fluorescence labeling colloid marker and curing agent according to the proportion of 10: 1; inserting needle from ventral faces of four legs of the young turtle and then inserting to the gap of the skin and muscle along a body direction from end of the leg; lightly pushing the injector to slowly draw theneedle head outwards in order to form a spot mark; after marking and injecting, use the wet cloth to erase marking liquid overflowing the needle hole. The method has good marking effect, has high mark retention rate and identification effect and does not damage the young turtle; the growth rate and survival rate of the turtle are not influenced by injecting mark by comparison of the marked group and non-marked group; the problems that the Chinese softshell turtle cannot be bred in the same pond without family individual marking during the traditional improved variety breeding and the estimation accuracy of the breeding production performance are changed; the estimation accuracy of improved variety breeding of Chinese softshell turtle is improved effectively.

The invention discloses a selection method of Chinese softshell turtle parent turtles. The selection method comprises the following steps of (1) selecting Chinese softshell turtle young turtles which are healthy, excellent in germplasm and high in activity; (2) feeding the selected Chinese softshell turtle young turtles to be adult turtles in an artificial turtle pond; (3) during the copulation and spawning season of Chinese softshell turtles, selecting male and female Chinese softshell turtle adult turtles which are healthy, less in damage, good in nutrition, and strong in constitution from fed Chinese softshell turtle adult turtle groups of different parent lines, putting the male and female Chinese softshell turtles in a parent turtle pond in proportion to copulate and spawn. The Chinese softshell turtle parent turtles selected by the selection method of Chinese softshell turtle parent turtles have the characteristics of more spawning number and higher hatching rate and survival rate.

The invention provides a method for ecologically breeding rice, crayfishes and turtles in a rice field and directionally breeding the crayfishes. By utilizing a biological characteristic that Chinesesoftshell turtles like eating the crayfishes according the chance of collaboration of the same time and same space, the residual crayfishes in the rice field are cleared, so that mating and reproduction of the crayfishes in the same rice field are prevented. On the other hand, allopatric crayfish parents are selected again, so that the directional optimized breeding of the crayfishes is realized.The method specifically comprises a method for directionally breeding the crayfishes, a method for ecologically breeding the rice, the crayfishes and the turtles, a method for producing crayfish feeds, a method for producing Chinese softshell turtle feeds and a method for producing Chinese softshell turtle baits. By implementing the method provided by the invention, the quality of the crayfishes and the Chinese softshell turtles can be improved, and high-quality rice is harvested, so that the mu production value is increased.

The invention provides a puffed particle compound feed for improving the body color of Chinese softshell turtle, and a preparation method thereof. The feed is prepared by mixing 15-30wt% of imported fish meal, 15-30wt% of domestic fish meal, 18-25wt% of flour, 5-15wt% of soybean meal, 2-4wt% of beer yeast, 1-3wt% of soybean oil, 0.8-1.5wt% of xanthophylls, 1.5-2.4wt% of a traditional Chinese medicinal regulating composition, 1-2wt% of a vitamin premix, 1-2wt% of a mineral matter premix, 1-2wt% of calcium dihydrogen phosphate and 0.1-0.3wt% of choline chloride. The feed has the advantages of comprehensive nutrition, reasonable matching, improvement of the body color of Chinese softshell turtle, whitening prevention, and enhancement of the fecundity, the viability and the immunity of Chinese softshell turtle.

The invention relates to a juvenile Chinese softshell turtle expanded feed. The juvenile Chinese softshell turtle expanded feed comprises the following components in parts by mass: 20 to 25 parts of small trash fishes, 10 to 15 parts of water earthworm meal, 5 to 10 parts of yam flour, 8 to 10 parts of purple sweet potato flour, 4 to 6 parts of orange peel powder, 5 to 8 parts of egg yolk, 4 to 7 parts of egg white, 0.06 to 0.1 part of glycine, 0.5 to 0.8 part of krill oil, 0.1 to 0.15 part of tea polyphenol, 0.05 to 0.1 part of glycine betaine, 0.02 to 0.04 part of monocalcium phosphate, 0.1 to 0.25 part of soybean oligosaccharides, 0.1 to 0.18 part of xylooligosaccharide, and 0.08 to 0.1 part of plant adhesive. The invention also relates to a preparation method of the juvenile Chinese softshell turtle expanded feed. Compared with the prior art, the juvenile Chinese softshell turtle expanded feed has the advantages that the nutrition is rich, the nutrition required by the growth of juvenile Chinese softshell turtle is provided, the survival rate and growth rate of juvenile Chinese softshell turtle are obviously improved, the feed coefficient is reduced, the stability in a water body is good, the easiness in disintegration is avoided, the waste of feed is little, and the pollution to water quality is little.

The invention discloses a special phagostimulant of Chinese softshell turtles and application of the phagostimulant. The phagostimulant is characterized by consisting of the following components in percentage by weight: 3-6 percent of methionine, 3-6 percent of lysine, 3-6 percent of arginine, 3-6 percent of alanine, 3-6 percent of glycine, 5-15 percent of dimethylpropiothetin, 5-10 percent of daghestan sweetclover herb, 5-10 percent of ferula asafetida and 40-60 percent of squid liver powder. One to two percent of phagostimulant is added into a commercially available compound feed; compared with a feed without the phagostimulant disclosed by the invention, the feed with the phagostimulant disclosed by the invention has the advantages that the ingestion time is shortened by 0.5-1 hour, the ingestion amount is increased by 5-10 percent, the corrosion ratio of the feed is reduced by 15-30 percent, the bait coefficient is reduced to be lower than 1.5, the nitrogen and phosphorus content of water is reduced by 15-20 percent, and the problems of drug residues and the like are solved.