147 results about "Cynoglossus semilaevis" patented technology

The invention discloses a method for inducing cleavage gynogenesis of fish fry of cynoglossus semilaevis, which comprises the steps of cynoglossus semilaevis sperm freezing storage, ultraviolet radiation of sperms, and induction and identification of the cleavage gynogenesis of the fish fry. The cynoglossus semilaevis sperm freezing storage method is established, and a method for inhibiting the first cleavage to induce the multiplication of embryo chromosome of the gynogenesis of the cynoglossus semilaevis through hydrostatic pressure is adopted so as to screen effective dilution and freezing method for the cynoglossus semilaevis sperm freezing storage and screen the hydrostatic pressure shock starting time, hydrostatic pressure and processing time suitable for the cleavage gynogenesis of cynoglossus semilaevis; and an identification method for the gynogenesis of the fish fry of the cynoglossus semilaevis is established. In the method, the fish fry of the cynoglossus semilaevis through cleavage gynogenesis is obtained for the first time, and the inductivity of the gynogenesis of the fish fry reaches 0.25 percent; and the method has the characteristics of advancement, high efficiency, reliability and reliability, can be used for solving the problems that male cynoglossus semilaevis grows slowly, the ratio of female cynoglossus semilaevis is low and the culture cost is high, and has significant application value and wide promotion and application prospect in the aspects of breeding of cynoglossus semilaevis fry, sex control, culture of all female fry, pure line breeding and the like.

A female specific molecular marker of tongue sole and application thereof comprises a screening method, DNA extraction of the tongue sole genomic, AFLP analysis of genomic DNA and screening of female specific molecular marker; also comprises clone and sequence of the female specific molecular marker of tongue sole, recycle of the female specific molecular marker of tongue sole, clone of female specific molecular marker and sequence of female specific molecular marker; additionally comprises application of one kind of female specific molecular marker for applying on the uninjurous identification of genetic sex of tongue sole, i.e. the genomic DNA of the tongue sole to be determined is collected, three pairs of specific primer are respectively designed according to the sequence of the female specific molecular marker of three tongue sole obtained, any pair of these three pairs of female specific primer is adopted to do PCR amplification, therefore the identification of genetic sex of tongue sole can be carried out. The female specific molecular marker of tongue sole and application thereof has the advantages of the advancement, the high efficiency, the accuracy and the reliability, having the important application value on the unisexual fingerlings production of the tongue sole and the wide application prospect on the genetic sex identification and the sex control research of other fishes.

The invention relates to an abduction method of a cynoglossus semilaevis diploid fry that is manually induced to be spawned and developed from female nucleus, comprising manually induced spawning of a parent fish, genetic inactivation of sperms, and an induction and identification method of the female nucleus developed diploid fry. The invention firstly establishes a method to obtain large batches of unfertilized ovum by manually induced spawning of the cynoglossus semilaevis, and builds up a method that the cynoglossus semilaevis sperms and lateolabrax japonicus sperms are adopted to induce the developing of the female nucleus of the cynoglossus semilaevis and obtain the female nucleus diploid fry, thus sieving effective manually induced spawning hormones kinds and dosages, and sieving cold shock beginning time and temperature and time that are suitable for the development of the female nucleus of the cynoglossus semilaevis, and the identification method of the female nucleus developed fry of the cynoglossus semilaevis is established. The insemination rate of the ovum of the cynoglossus semilaevis obtained by the method is 60 to 89 percent, the hatch ability is 34 to 79 percent, and the induction rate of the female nucleus developed fry is 0.4 to 6.3 percent. The invention is characterized by advancement, high effect, practicability and reliability, and has important application value and wide popularization prospect on the breeding of fry kinds of the cynoglossus semilaevis, sex control and hologynic breeding.

The invention relates to a novel farming method of cynoglossus semilaevis. A main mode is of a combined mode of a warmhouse booth, heavy brine, geothermal freshwater and liquid oxygen. The novel farming method specifically comprises the steps of: purifying a water source; conditioning water temperature and water quality; carrying out ultraviolet sterilization; carrying out high-efficient oxygenation; farming in a farming workshop; recovering farming wastewater; and enabling the recovered farming wastewater to enter into a distribution reservoir according to the proportion of 30%-50%, conditioning the water temperature and the water quality again and enabling the wastewater to enter into a farming pond. According to the novel farming method disclosed by the invention, the use of fire coal and a Roots blower can be stopped, the energy-saving effect is significant, and the farming risk caused by insufficient electric power is simultaneously reduced; and the problem that the farming of the cynoglossus semilaevis is limited in a plurality of regions with abundant heavy brine and geothermal resources and the insufficient supply of seawater, and the development of the farming industry of the cynoglossus semilaevis is benefited.

The invention discloses a feed for parent fish of Cynoglossus semilaevis and belongs to a technology for preparing a marine fish compound feed. In the feed, the adding amount of fat is 8 percent, and the ratio of n-3 fatty acid to n-6 fatty acid is 2.81. The fat added into the feed for the parent fish of the Cynoglossus semilaevis is fish oil and soybean oil, and the content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the fish oil is higher than 30 percent; and according to the formula, the feed for the parent fish of the Cynoglossus semilaevis comprises 70 percent of white fish meal, 6 percent of casein, 10 percent of flour, 2 percent of phospholipid, 1 percent of choline, 0.5 percent of vitamin C, 0.5 percent of multi-vitamin, 0.5 percent of complex mineral, 1.5 percent of calcium hydrophosphate, 2.5 percent of soybean oil and 5.5 percent of fish oil. A certain proportion of fish oil which is rich in the EPA and the DHA is added into the feed for the Cynoglossus semilaevis, and is matched with the soybean oil, so that the n-3 fatty acid and the n-6 fatty acid in an appropriate ratio are provided for the Cynoglossus semilaevis, the egg laying amount of the Cynoglossus semilaevis can be improved, the abnormality rate of fries can be reduced, and the lengths of 12-day fries can be increased.

The invention relates to a gender-specific microsatellite marker for Cynoglossus semilaevis and the application of same in the identification of superfemale Cynoglossus semilaevis. The Gender-specific microsatellite marker for the Cynoglossus semilaevis is characterized in that the nucleotide sequences of a microsatellite marker are respectively SEQ ID NO: 1 and SEQ ID NO: 2; and the upstream and downstream primer sequences of a primer used for amplifying the specific microsatellite marker are respectively SEQ ID NO: 3 and SEQ ID NO: 4. The primer is used for identifying individual female or male Cynoglossus semilaevis, the amplified product segment of the superfemale Cynoglossus semilaevis is 218 bp, and the amplified product of the female Cynoglossus semilaevis is two DNA segments, the sizes of which are respectively 216-220bp and 204-208 bp, and the amplified product of the male Cynoglossus semilaevis is one DNA segment, the size of which is 204-208 bp. The invention screens the specific microsatellite markers for W and Z chromosomes of the Cynoglossus semilaevis and designs the microsatellite primer. ZW female Cynoglossus semilaevis, WW superfemale Cynoglossus semilaevis and ZZ male Cynoglossus semilaevis can be fast identified by utilizing the microsatellite marker, thereby solving the problem of hard identification of the WW superfemale Cynoglossus semilaevis and the normal ZW male Cynoglossus semilaevis during the sex control and the unisexual seed cultivation of the Cynoglossus semilaevis.

Disclosed is artificial micro-particle addictive for cynoglossus semilaevis young fry which comprises white fish meal, shrimp powder, mussel powder, calamari powder, yeast powder, hydrolyzed fish meat protein, fish oil, alpha-starch, gelatin, inorganic salts mixture, vitamins mixture, feeding promoting agent, coloring matter, anti-oxidant, micro ecological preparation and lecithin by the weight proportions of 35-40, 10-15, 10-15, 8-12, 3-6, 5-8, 3-6, 6-12, 1-3, 1-3, 1-3, 0.1-0.2, 0.01-0.03, 0.05-0.08, 0.1-0.3, 5-8.

This invention relates to specific molecule labeling of the sex of semi-sliding tongue soles and its genetic sex test method including the pick-up of the blood DNA, the AFLP analysis of DNA in the gene set, selection of the AFLP molecular labeling and a method for genetic sex check up of semi-sliding tongue sole, which selects 4 from 64 primer combinations to generate female specific DNA segments and selects 7 female specific AFLP molecular labels of the sole to set up the molecule labeling technology of its genetic sex authentication.

The invention relates to a method for establishing and identifying a cynoglossus semilaevis testis cell line, which comprises the following steps: adopting a MEM (Minimum Essential Medium), adding 20 percent of fetal calf serum, 0.1 percent of B-mercaptoethanol, 2 ng / ml of human alkaline fibroblastic growth factors, 1 ng / ml of leukemia inhibiting factors, 1 nmol of sodium pyrurate and 1 nmol of glutamine and preparing into a complete medium; inoculating a tissue block into a culture bottle, overturning and inversely placing the bottle to culture for 3 h and positively placing the culture bottle after the tissue block is attached onto a wall, so that the tissue block is soaked into the culture medium for culture. A trypsin digestion method is adopted for subculturing cells. One cynoglossus semilaevis testis cell line is established by adopting the above method and is subcultured to fiftieth generations. Meanwhile, the invention also provides a method for identifying a chromosome of the established cell line and the level of a molecular marker and a method for identifying the sensitivity of the cell line to related viruses. The method for establishing the cynoglossus semilaevis testis cell line can be used for culturing other fish gland cells and establishing the cell line, thereby having wider promotion and application prospect.

The invention first provides a Cynoglossus semilaevis gender specific microsatellite marker, and comprises a microsatellite marker located in the Z chromosome, and the nucleotide sequence is SEQ ID NO:1. The invention also provides primers designed based on the above microsatellite marker, and the sequences of the upstream primer and the downstream primer are SEQ ID NO:2 and SEQ ID NO:3 respectively. The invention screens a Cynoglossus semilaevis gender specific microsatellite marker, and the Cynoglossus semilaevis gender specific microsatellite marker is subjected to SCAR conversion. Primers marked by SCAR are designed for Cynoglossus semilaevis heredity gender identification. Female, male and superfemale individuals of Cynoglossus semilaevis can be distinguished rapidly, accurately and effectively. Because the marker has characteristics that objective straps can be amplified in females and males and the objective straps can be distinguished with agarose electrophoresis, the time for accurate identification of Cynoglossus semilaevis heredity genders is shortened obviously, the on-site batch identification of Cynoglossus semilaevis heredity genders in a culturing farm of Cynoglossus semilaevis can be carried out, the detection cost is saved, and the work efficiency and accuracy of on-site detection of Cynoglossus semilaevis heredity genders in a culturing farm are raised.

The present invention provides a screening method, a kit and applications of a cynoglossus semilaevis gunther sex conversion genetic control site. The screening method comprises: carrying out full-genome molecular marking on genetic female cynoglossus semilaevis gunther to obtain a plurality of SNP loci; and carrying out full-genome association analysis on the plurality of the SNP loci by adopting whether the transgenic female fish has sex conversion as the trait to obtain the cynoglossus semilaevis gunther sex conversion genetic control site. According to the present invention, from the perspective of the genetic control for controlling the sex conversion of the female fish, the full-genome analysis is performed by using the correlation between the unique SNP loci of the transgenic female fish and the sex conversion so as to find the molecular switch for controlling the sex conversion of the genetic female fish, wherein the molecular switch is the 6676874 site nucleotide on the Z chromosome; and by using the site to control the copulation method of the male cynoglossus semilaevis gunther and the female cynoglossus semilaevis gunther, the proportion of the female cynoglossus semilaevis gunther being not subjected to sex conversion in the artificial breeding cynoglossus semilaevis gunther progeny is increased so as to improve the breeding production benefits.

The invention relates to a cynoglossus semilaevis gunther sex-linked microsatellite marker and genetics sex testing method comprising a PCR method and a PCR testing method, wherein the PCR method is used for screening and testing of a cynoglossus semilaevis gunther sex-linked microsatellite marker, clone of female peculiar allelic gene, sequence analysis, peculiar primer design and cynoglossus semilaevis gunther genetics sex; and the PCR testing method is used for creating the cynoglossus semilaevis gunther genetics sex according to the obtained cynoglossus semilaevis gunther sex-linked microsatellite marker primer and female peculiar allelic gene. The invention ensures that the cynoglossus semilaevis gunther sex-linked microsatellite marker and the female peculiar allelic gene are screened for the first time, establishes the PCR technique tested by the cynoglossus semilaevis gunther genetics sex, has the characteristics of high efficiency, accuracy and stability, has important application value in the cynoglossus semilaevis gunther sex control and unisexuality seed production, and also has important application prospect in the sex determination gene research by cloning the cynoglossus semilaevis gunther.

The invention relates to the filed of molecular biology, in particular to cynoglossus semilaevis natural killer (NK)-lysin and application method of the cynoglossus semilaevis NK-lysin. NK-lysin is as the display of an amino acid sequence in sequencer (SEQ) ID No.1. The application method is that the cynoglossus semilaevis complementary deoxyribonucleic acid (c DNA) serves as a template, and a primer F1 and a primer R1 are utilized to carry out polymerase chain reaction (PCR) amplification. After a PCR product is connected with an expressive vector, plasmids (p CNK1) are obtained, the plasmids (p CNK1) are injected into fishes and the antiviral capacity and the antibacterial capacity of the fishes can be obviously intensified.

The invention relates to the field of molecular biology, and in particular to a galectin-3 binding protein, and preparation and application thereof. The galectin-3 binding protein is shown as an amino acid sequence SEQ ID No.1 in the sequence table. The preparation method is as below: using Cynoglossus semilaevis cDNA as a template; conducting PCR amplification by primers F1 and R1; connecting PCR products to an expression vector to obtain a plasmid pETG3BP; conversing BL21DE3 to obtain a transformant BL21 / pETG3BP; inducting by isopropyl-beta-D-thiogalactoside; and purifying the recombinant protein with affinity chromatography column to obtain the galectin-3 binding protein. The galectin-3 binding protein has significant binding ability to various bacteria.

The temperature and lighting controlling technology of Cynoglossus semilaevi Gunther parent fish spawning includes selecting parent fish, reinforced culturing and artificially controlling the water temperature and lighting for the parent fish to spawn. The technological key points of the present invention includes culturing of Cynoglossus semilaevi Gunther parent fish, water temperature regulation, lighting regulation, evening lamp setting, etc. to make the sexual glands of the parent fishes develop and mature synchronously, make the parent fishes spawn naturally in fixed time and obtain great amount of high quality fertilized eggs and high fertilization rate.

The invention relates to a method for using the frozen sperm of bass to induce the cultivation of sliding-tongue ovum thelykaryon, which comprises that: using the bass sperm frozen in the liquid nitrogen, to induce the thelykaryon cultivation of sliding-tongue ovum; defreezing the sperm in 37Deg.C water bath, taking 100muL sperm to dilute the MPRS for 10 times, to be arranged in the cultivate container at 6Deg. C; using 1000muj / cm2 ultraviolet to radiate for 0.2min, to inactivate the sperm; then using the inactive sperm to induce the fecundation with the ovum; in 5min of fecundation, using 2Deg. C water bath to shock the zygote, while the shock time is 20min; arranging the blast into the sea bath at 23Deg. C to be cultivated. The invention has low cost.

The invention discloses a semi-sliding-tongue halibut female astopic AFLP segment and PCR authenticating method of genetic sex, which comprises the following steps: recycling female astopic AFLP segment; cloning AFLP segment; analyzing sequence; authenticating semi-sliding-tongue halibut through PCR method; establishing to separate and clone semi-sliding-tongue halibut female astopic AFLP segment; obtaining female astopic DNA segment; designing astopic primer; transmitting AFLP mark into SCAR mark; creating PCR technology for genetic sex authentication of semi-sliding-tongue halibut.

The invention discloses a method for pond culture of cynoglossus semilaevis gunther by means of the biofloc technique. The method comprises the steps of biofloc cultivation and breeding. In the biofloc cultivation process, aquaculture water is extracted to a cultivation unit; a carbon source and / or nitrogen source is added to a culture pond to enable the total content of carbon in water to be 5.5-45 mg / L, the total content of nitrogen in water to be 0.55-2.25 mg / L and carbon nitrogen ratio to be 10-20:1; water in the culture pond needs to be fully aerated, dissolved oxygen in water is maintained to be 5.5-8.5 mg / L, pH value is maintained to be 6-8, and temperature is maintained to be over 20 DEG C; when the total suspended solid in water in the culture pond reaches 100-500 mg / L, water is prepared for use. In the breeding process, cynoglossus semilaevis gunther is placed in the cultivation unit with released density being 10-150 pieces / m<2>. Compared with ordinary methods, the method has the advantages that water changing frequency is low, bait feeding amount is small, and obtained cynoglossus semilaevis gunther rarely gets sick and is high in yield.

The invention provides a bacterial disease resistance related gene screened from cynoglossus semilaevis. The nucleotide sequence of the gene is SEQ ID NO: 1, and the sequence of a coded protein is SEQID NO: 2. The gene provided by the invention is relevant to the bacterial disease resistance of the cynoglossus semilaevis, and the expression amount of the gene in intestine is relevant to the disease resistance of a fish body. When the expression level is higher, the disease resistance of the fish body is higher. An in-vitro recombinant expressed protein thereof can remarkably restrain the multiplication of certain types of gram-negative bacteria, so that the gene has an application value on the aspects of breeding of a cynoglossus semilaevis disease resistance family, disease control, research of feed additives and bactericide and the like.

The invention aims at providing an establishment method of an ovary cell line of cynoglossus semilaevis, which comprises the following steps: 1) removing the outermost membrane of the ovary tissue of cynoglossus semilaevis under a sterile condition, cutting the tissue into small blocks in a culture solution, flushing the tissue blocks with a PBS solution and digesting with a trypsin solution, wherein the solution after trypsin digestion contains cells, cell clusters and tissue blocks not completely digested; and 2) centrifuging the solution to remove the supernatant trypsin, and suspending the cells, cell clusters and small tissue block precipitates with a culture solution; after a suspension is obtained, inoculating into a culture plate treated by the type-I collagen; adding a culture solution, and culturing in a biochemical incubator at 24 DEG C; and performing subculture to finish establishment of the ovary cell line. In the establishment method provided by the invention, an ovary cell line of cynoglossus semilaevis is successfully established by use of the ovary tissue of cynoglossus semilaevis, the established cell line can be continuously passed, the passage cells obtained by the method can be passed for over 60 generations, and a great quantity of ovary cells can be provided.

The invention provides a cynoglossus semilaevis sex chromosome-linked DNA segment and application thereof. A sequence of a DNA segment on a Z chromosome is SEQ ID NO:1; a sequence of a DNA segment on a W chromosome is SEQ ID NO:2. The DNA segment is used for designing a molecular marker for identifying the genetic sex of cynoglossus semilaevis. Two Z-W chromosome homologous and different DNA segments are screened from cynoglossus semilaevis whole genome information, a primer is designed for identifying the genetic sex of the cynoglossus semilaevis, and the genetic sex of the cynoglossus semilaevis can be distinguished quickly, accurately and effectively. By adopting a method, specific purpose stripes can be amplified in male and female individuals and can be distinguished by agarose electrophoresis, the time for accurately identifying the genetic sex of the cynoglossus semilaevis is shortened, the method is suitable for identifying the genetic sex of the cynoglossus semilaevis in a simple environment of a farm, and detection time and cost are reduced.

The invention discloses a granular feed for adult fish of cynoglossus semilaevis. The granular feed comprises the following components: animal nutritional materials, plant nutritional materials, Chinese herbal medicines, vitamins, trace elements, lentinan, stachyose hydrate, nitrifying bacteria, marine yeast, photosynthetic bacteria, glucan, methionine and L-lysine. A preparation method comprises the following steps: (1) manufacturing raw materials; (2) synthesizing a biological material; (3) converting to a cooked material; (4) puffing and granulating; (5) drying; (6) spraying and coating; and (7) performing vacuum drying. By using the feed disclosed by the invention, the survival rate, disease resistance and growth rate of the adult fish of cynoglossus semilaevis and the conversion efficiency of the feed can be improved, and the cost of the feed in the cultivation process can be reduced.

An Aeromonas salmonicida subspecies (Aeromonas almonicidasubsp. masoucida) is isolated from Cynoglossus semilaevis Gunther cultured in Shandong Province, China, the preservation number of the Aeromonas almonicidasubsp. masoucida is CCTCCM2018085. A pathogenic bacteria strain of ascites disease is isolated from the Cynoglossus semilaevis Gunther for the first time. Antigens of the strain contain protective antigens against Aeromonas salmonicida, the strain is suitable for preparing various vaccines against the Aeromonas salmonicida, and is capable of reducinge losses caused by diseases in aquaculture, reducing or eliminating abuse of chemical drugs such as disinfectants and antibiotics caused by the Aeromonas salmonicida, and significantly improving the safety of aquaculture animals and products, and reducing bio-safety risks caused by increase of drug resistance of pathogenic bacteria.

The invention relates to a high-efficient induction method of tetraploid cynoglossus semilaevis fish fries, and the method comprises the steps of induction of the tetraploid cynoglossus semilaevis fish fries and identification of the tetraploid cynoglossus semilaevis fish fries, and is characterized by performing pressure shock treatment for 3.5-6 minutes under hydrostatic pressure of 38-44MPa within 19-28 minutes after fertilization; and transferring fertilized eggs into seawater at the temperature of 19-23 DEG C for culture and incubation after completing the shock treatment. According to the invention, a technical method which can be used for effectively inducing the fertilized eggs of cynoglossus semilaevis to produce tetraploid fish fries in a doubled manner is established, and a technical parameter for inhibiting the first cleavage of the eggs of the cynoglossus semilaevis is firstly determined. The method is simple to operate, strong in practicality, easy to implement, safe and reliable; and the induction efficiency of the tetraploid fish fries is high. By adopting the method, a new technical approach is provided for the sex control and polyploid breeding of the cynoglossus semilaevis.

The invention discloses a method for breeding cynoglossus semilaevis fry in artificial halogen salt water. The method mainly includes the step that the cynoglossus semilaevis fry are bred in halogen salt water formed by mixing underground brine or concentrated brine used after salt manufacturing with fresh water or low-salinity seawater. The method particularly includes the steps of mixing the halogen salt water for seedling breeding, incubation of fertilized eggs, early breeding of the fry and intermediate breeding of the fry. Salt reducing breeding is conducted in the early breeding process and the intermediate breeding process of the fry, salinity can be gradually reduced to 20 in the early breeding stage, and salinity of breeding water can be reduced to 10 in the intermediate breeding stage. By the adoption of the method, the breeding survival rate of the cynoglossus semilaevis fry can be increased, the albino rate of the fry is reduced, seedling breeding cost is greatly reduced, and cynoglossus semilaevis breeding space can be conveniently expanded.

The invention relates to an induction method of a cynoglossus semilaevis gynogenesis diploid fish fry, which comprises a cynoglossus semilaevis ovum artificial gynogenesis method and a gynogenesis fish fry identifying method. The induction method comprises the steps of: firstly, establishing a method for obtaining the gynogenesis diploid fish fry through inducing cynoglossus semilaevis ovum gynogenesis by adopting a cynoglossus semilaevis sperm and a perch sperm; screening to obtain cold shock starting time, cold shock temperature and time of the cynoglossus semilaevis egg gynogenesis; and establishing an indentifying method of the cynoglossus semilaevis gynogenesis fish fry. The induction rate of the gynogenesis fish fry is 0.4-6.3 percent. The invention has the characteristics of advanced technology, high efficiency, practicability and reliability, and has important application value and wide popularization and application prospects on cynoglossus semilaevis sex control and full female breeding.

The invention discloses a preparation method of a Cynoglossus semilaevis vibrio anguillarum vaccine, which is characterized in that Cynoglossus semilaevis pathogeny Listonella anguillarum BH1 serves as an immunogen, and Astragalus mongholicus lixivium serves as an adjuvant. The preparation method comprises the following steps: inoculating the Cynoglossus semilaevis pathogeny Listonella anguillarum BH1 bacterial strain on a common nutrient broth culture medium; after the bacterial strain is cultured, inactivating by formaldehyde to obtain inactivated bacteria; after dipping the Astragalus mongholicus with distilled water, decocting, and filtering; condensing until the final concentration is 1g of raw drug per ml, and obtaining the Astragalus mongholicus lixivium; and mixing the inactivatedbacteria with the Astragalus mongholicus lixivium to obtain the Cynoglossus semilaevis Vibrio anguillarum vaccine. When the vaccine prepared with the method disclosed by the invention is used for immunizing Cynoglossus semilaevis, the capability of the Cynoglossus semilaevis on resisting Vibrio anguillarum infection can be obviously improved, Vibrio anguillarum infection during the culture production of the Cynoglossus semilaevis can be effectively prevented, the death rate of the Cynoglossus semilaevis is reduced, the culture yield of the Cynoglossus semilaevis is improved, the Cynoglossus semilaevis culture production is guaranteed to healthily and sustainably develop, and the economic benefit for Cynoglossus semilaevis culture production is improved.

The invention discloses a method for cultivating chrysophyceae by utilizing cynoglossus semilaevis cultivation waste water, including the steps of cynoglossus semilaevis cultivation waste water precipitation or filtration, mixed culture solution preparation and isochrysis zhanjiangensis cultivation. The invention adopts culture solution taking cynoglossus semilaevis cultivation waste water as main body, thus greatly reducing cultivation cost, and cultivation waste water purification is realized and carbon emission is reduced while the microalgae is obtained. Besides, cultivation water quality is improved while isochrysis zhanjiangensis with higher economic value is obtained, and the invention has better economic and social benefits.

The invention relates to a fish feed, in particular to compound feed for cynoglossus semilaevis gunther. The compound feed for the cynoglossus semilaevis gunther comprises the following ingredients in parts by weight: 23-25 parts of fish powder, 30-38 parts of housefly larvae powder, 5-10 parts of shell mussel powder, 10-15 parts of astragalus root dregs, 6-8 parts of yeast powder, 0.02-0.05 part of Vitamin C, and 0.01-0.02 part of Vitamin E. A plurality of ingredients are effectively mixed, proper housefly larvae powder can improve the palatability for the cynoglossus semilaevis gunther, the contents of protein and fat of the feed can satisfy the growth for the cynoglossus semilaevis gunther, the added astragalus root dregs, Vitamin C and Vitamin E can effectively reduce the infection risk of the cynoglossus semilaevis gunther, during use, a certain amount of complex feed can be added into the feed to increase microelement and basic nutrient.

The invention relates to the field of molecular biology, in particular to Cynoglossus semilaevis thioredoxin and a preparation method and application thereof. The thioredoxin is shown as an amino acid sequence in a sequence table SEQ ID No.1. The preparation method comprises the following steps of: constructing a plasmid pETrx, transforming the plasmid pETrx by using BL21(DE3) to obtain BL21(DE3) / pETrx, inducing by using isopropyl-beta-D-isopropylthiogalactoside, and purifying recombinant protein by using an affinity chromatography column to obtain the thioredoxin. The thioredoxin has remarkable reductase activity, a remarkable antioxidation effect and a remarkable cell growth promotion effect.