Cultivation method and application of artificially induced pseudo-male golden pomfret in batches

Abstract

The present invention relates to the field of aquaculture technology, and more particularly to a method and application for cultivating artificially induced pseudo-male golden pomfret in batches. The method includes: weighing aromatase inhibitor and / or 17α-methyltestosterone hormone and dissolving them in ethanol to obtain induction hormone A, B, C mother liquor; placing fry in a circulating water culture system; soaking rotifers with induction hormone A mother liquor; feeding rotifers every day for fry 3 to 20 days old; adding induction hormone A mother liquor to breeding feed, feeding 21 to 80-day-old golden pomfret; transferring to an outdoor pond for breeding; adding induction hormone B mother liquor to breeding feed, feeding 81-120-day-old golden pomfret; transferring fry to sea cages for breeding; adding induction hormone C mother liquor to breeding feed, feeding 121-180-day-old golden pomfret every day; stopping adding hormone feeding after 180 days of age. Advantages: effectively controlling the direction of sex differentiation, promoting gonad reversal, and obtaining pseudo-male golden pomfret reserve parents.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, and in particular to a method and application of cultivating batches of artificially induced pseudo-male golden pomfret. Background Art

[0002] Golden pomfret is one of the important marine economic fish in my country and a wide-salt warm-water fish. The meat of golden pomfret is tender, delicious and grows fast. It is mainly farmed in Guangdong, Guangxi, Hainan, Fujian and other sea areas. It has become the second largest marine farmed fish in my country. According to the 2024 China Fisheries Statistical Yearbook report, the farming volume reached 292,000 tons in 2023, with an output value of about 20 billion yuan. The growth traits of golden pomfret are sexually dimorphic, with females growing faster than males, and showing significant differences at 8 months of age. For this reason, if the sex of golden pomfret can be controlled and the advantage of the faster growth rate of females can be used for single-sex farming, higher yields and benefits can be obtained under the same conditions. In response to this situation, super-female and super-male offspring can be obtained by mating the pseudo-female fish after sex reversal with normal females, and then all-female groups can be cultivated.

[0003] At present, the main methods of artificially controlling the sex of fish include interspecific hybridization, exogenous hormone induction, and artificially induced gynogenesis. Interspecific hybridization and artificially induced gynogenesis are only carried out in a few fish, and most fish use exogenous hormone induction methods to breed sex-reversed fish. In the current research on fish sex reversal, a single hormone is mostly used for induction, and sex-reversed individuals can be obtained in a short time. However, the gonad development cycle of golden pomfret is long, and sex-reversed individuals cannot be obtained using conventional methods. Therefore, it is necessary to establish a unique sex reversal method for golden pomfret based on its gonad development characteristics. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for cultivating artificially induced pseudo-male golden pomfret in batches and its application.

[0005] The first object of the present invention is to provide a method for cultivating pseudo-male golden pomfret by artificially inducing batches of the pomfret, which specifically comprises the following steps:

[0006] S1. Prepare the mother solution of inducing hormone: weigh the aromatase inhibitor and dissolve it in ethanol solution to obtain the mother solution of inducing hormone A; weigh the aromatase inhibitor and 17α-methyltestosterone hormone and dissolve them in ethanol solution to obtain the mother solution of inducing hormone B; weigh the 17α-methyltestosterone hormone and dissolve it in ethanol solution to obtain the mother solution of inducing hormone C;

[0007] S2. Induced rearing of newly hatched golden pomfret larvae with undifferentiated gonads; specifically comprising the following sub-steps:

[0008] S201. In a recirculating aquaculture system, placing newly hatched golden pomfret fry with undifferentiated gonads;

[0009] S202. soaking the rotifers in the mother solution of inducing hormone A for 20 to 40 minutes; feeding the soaked rotifers to the newly hatched golden pomfret larvae daily from the 3rd day of age until the larvae are 20 days old;

[0010] S203. The mother solution of inducing hormone A is added to the breeding feed to prepare compound feed A; the compound feed A is fed to the 21-80-day-old golden pomfret fry every day, and the state of the golden pomfret fry is observed and detected at any time;

[0011] S3. Induced rearing of golden pomfret fry: The golden pomfret fry were transferred to an outdoor pond for breeding; the mother solution of inducing hormone B was added to the breeding feed to prepare compound feed B; the compound feed B was fed to the golden pomfret fry aged 81-120 days every day, and the status of the golden pomfret fry was observed and detected at any time;

[0012] S4. Male differentiation induction breeding of golden pomfret: golden pomfret fry were transferred to sea cages for breeding; the mother solution of induction hormone C was added to the breeding feed to prepare compound feed C; compound feed C was fed to golden pomfret aged 121-180 days every day, and the status of golden pomfret was observed and tested at any time;

[0013] S5. After the golden pomfret reaches 180 days of age, stop adding hormones to the feeding and feed it with breeding feed without hormones instead.

[0014] Preferably, the concentration of the ethanol solution in step S1 is 95%; and the aromatase inhibitor is letrozole hormone.

[0015] Preferably, the concentration of the inducing hormone A mother solution is 50-150 μg / L.

[0016] Preferably, the concentration of the mother solution of inducing hormone A is 100 μg / L; the soaking time of the rotifers in step S202 is 30 minutes, and the rotifers are 9-15 days old, 100-200 μm in diameter, and the rotifers are small Celsius rotifers.

[0017] Preferably, the amount of letrozole hormone added in compound feed A is 80-120 mg / kg; the amount of letrozole added in compound feed B is 40-60 mg / kg, and the amount of 17α-methyltestosterone added is 80-120 mg / kg; the amount of 17α-methyltestosterone added in compound feed C is 140-180 mg / kg.

[0018] Preferably, the amount of letrozole hormone added to compound feed A is 100 mg / kg; the amount of letrozole added to compound feed B is 50 mg / kg, and the amount of 17α-methyltestosterone added is 100 mg / kg; the amount of 17α-methyltestosterone added to compound feed C is 150 mg / kg.

[0019] Preferably, the diameter of the circulating aquaculture system is 1.5-2.5 m and the water depth is 0.8-1.0 m.

[0020] Preferably, the number of times the golden pomfret is fed per day in step S3 and step S4 is 2-3 times.

[0021] The second purpose of the present invention is to provide a method for cultivating pseudo-male golden pomfret by artificially inducing batches of artificial male golden pomfret and its application in cultivating pseudo-male golden pomfret.

[0022] The third object of the present invention is to provide a method for cultivating artificially induced pseudo-male golden pomfret in batches for application in cultivating all-female golden pomfret seedlings, which is characterized by: using the cultivated pseudo-male golden pomfret and normal female golden pomfret as parents of the F0 generation for mating, and after obtaining offspring, selecting super-female golden pomfret as F1 generation parents; and mating the super-female golden pomfret with normal male golden pomfret parents to obtain all-female golden pomfret seedlings.

[0023] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0024] In view of the above problems, the present invention provides a pseudo-male golden pomfret reserve parent induction method and breeding application, which uses aromatase inhibitor letrozole and androgen 17α-methyltestosterone to induce the masculinization of golden pomfret with undifferentiated gonads, which can achieve the male differentiation of golden pomfret with female genetic sex, and obtain female individual gonads that reverse and develop into fully male individuals, so as to serve as reserve parents. The method can be used to induce a pseudo-male golden pomfret population, and then obtain reserve parents through cultivation, and then carry out breeding applications to obtain all-female golden pomfret seedlings and improve economic benefits. The method of the present invention has the advantages of strong operability, little impact on young fish, mild and efficient, and not being restricted by the natural environment. It also opens up technical approaches for the study of golden pomfret sex control and unisexual breeding, and further explains the sex development pattern of golden pomfret.

[0025] In summary, the present invention provides a method for inducing pseudo-male golden pomfret reserve parents, which can effectively promote gonad reversal by feeding different hormones at different stages of golden pomfret gonad development, obtain pseudo-male golden pomfret reserve parents, and carry out breeding applications after intensive cultivation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the result of genotype detection and genetic sex identification of the golden pomfret sample provided by the embodiment of the present invention.

[0027] Figure 2 Schematic diagram of intersexual slices of golden pomfret provided according to an embodiment of the present invention; in the figure, (A) is a slice of female ovary of the control group; (B) is a slice of golden pomfret in intersexual gonad after hormone treatment; (C) is a slice of testis of male after sex reversal after hormone treatment; Oc represents oocyte, and Sc represents spermatocyte.

[0028] Figure 3 The present invention provides a technical roadmap for cultivating all-female golden pomfret seedlings according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are represented by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, the detailed description thereof will not be repeated.

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0031] The present invention provides a method for cultivating artificially induced pseudo-male golden pomfret in batches, which specifically comprises the following steps:

[0032] S1. Prepare the mother solution of inducing hormone: weigh a certain amount of aromatase inhibitor letrozole hormone and dissolve it in 95% ethanol solution to obtain the mother solution of inducing hormone A;

[0033] Weigh a certain amount of letrozole hormone and 17α-methyltestosterone hormone respectively and dissolve them in 95% ethanol solution to obtain the induction hormone B mother solution;

[0034] Weigh a certain amount of 17α-methyltestosterone hormone and dissolve it in 95% ethanol solution to obtain the induction hormone C mother solution.

[0035] S2. Induced rearing of newly hatched golden pomfret larvae with undifferentiated gonads; specifically comprising the following sub-steps:

[0036] S201. In a recirculating aquaculture system, placing newly hatched golden pomfret fry with undifferentiated gonads;

[0037] The diameter of the circulating aquaculture system is 1.5-2.5m, and the water depth is 0.8-2m; specifically, the diameter is 2m, and the water depth is 1m or 1.5m;

[0038] S202. The rotifers were soaked in a mother solution of induction hormone A with a concentration of 50-150 μg / L for 20-40 min; the rotifers were 9-15 days old and 100-200 μm in diameter; the newly hatched golden pomfret larvae were fed with soaked rotifers every day from 3 days old (dph) until the larvae were 20 days old;

[0039] In a specific embodiment, the concentration of the inducing hormone A mother solution is 100 μg / L, and the rotifer soaking time is 30 min;

[0040] S203. Add the mother solution of inducing hormone A to the breeding feed to prepare compound feed A; feed the compound feed A to golden pomfret fry aged 21 to 80 days every day, and observe and detect the status of the golden pomfret fry at any time.

[0041] S3. Induction rearing of golden pomfret fry; specifically comprising the following sub-steps:

[0042] S301. The fry of golden pomfret are transferred to outdoor ponds for breeding, which is conducive to their faster growth;

[0043] S302. Add the mother solution of inducing hormone B to the breeding feed to prepare compound feed B; feed the compound feed B to the golden pomfret fry aged 81-120 days 2-3 times a day; observe and detect the status of the golden pomfret fry at any time.

[0044] S4. Male differentiation induction breeding of golden pomfret; specifically comprising the following sub-steps:

[0045] S401. The golden pomfret fry are transferred to the sea cages for breeding, making the environment more conducive to its growth and growing faster;

[0046] S402. The mother solution of inducing hormone C is added to the breeding feed to prepare compound feed C; the compound feed C is fed to the golden pomfret aged 121-180 days daily, 2-3 times a day; the state of the golden pomfret is observed and detected at any time;

[0047] S5. After the golden pomfret reaches 180 days of age, stop adding hormones to the feeding and feed it with breeding feed without hormones instead.

[0048] Preferably, the breeding feed is the golden pomfret compound feed produced by Guangdong Yuehai Feed Group.

[0049] Preferably, the amount of letrozole hormone added in compound feed A is 80-120 mg / kg; the amount of letrozole added in compound feed B is 40-60 mg / kg, and the amount of 17α-methyltestosterone added is 80-120 mg / kg; the amount of 17α-methyltestosterone added in compound feed C is 140-180 mg / kg.

[0050] In a specific embodiment, the amount of letrozole hormone added to compound feed A is 100 mg / kg; the amount of letrozole added to compound feed B is 50 mg / kg, and the amount of 17α-methyltestosterone added is 100 mg / kg; the amount of 17α-methyltestosterone added to compound feed C is 150 mg / kg.

[0051] Example 1

[0052] This embodiment provides a method for cultivating artificially induced pseudo-male golden pomfret in batches, which specifically comprises the following steps:

[0053] S1. Prepare the mother solution of induction hormone: weigh a certain amount of aromatase inhibitor letrozole hormone and dissolve it in 95% ethanol solution to obtain the mother solution of induction hormone A; weigh a certain amount of letrozole hormone and 17α-methyltestosterone hormone and dissolve them in 95% ethanol solution to obtain the mother solution of induction hormone B; weigh a certain amount of 17α-methyltestosterone hormone and dissolve it in 95% ethanol solution to obtain the mother solution of induction hormone C.

[0054] 17α-methyltestosterone is a synthetic androgen drug. Due to its methylation modification in structure, especially the methyl group at the 17α position, it is more stable in the body than natural testosterone, especially in the intestines and liver of fish. This chemical modification enhances its anti-metabolism ability, making it more effective when administered orally and in water. Compared with other natural hormones, it can remain active for a longer time, making it more effective in the process of sex reversal. At a reasonable dose, 17α-methyltestosterone has relatively few side effects and has a low negative impact on the growth, health and survival rate of fish. 17α-methyltestosterone is relatively economical and has a stable supply, making it suitable for large-scale aquaculture applications.

[0055] S2. Induced rearing of newly hatched golden pomfret larvae with undifferentiated gonads; specifically comprising the following sub-steps:

[0056] S201. In a recirculating aquaculture system with a diameter of 2m and a water depth of 1.5m, wash and disinfect the water buckets, add seawater with a salinity of 33%, maintain the water temperature at 26-28℃, pH at 8.2-8.4, and ammonia nitrogen at less than 0.01mg / L. Aerate the aquaculture water buckets to maintain dissolved oxygen at more than 6mg / L. Put 10,000 3-day-old newly hatched fry with undifferentiated gonads in each bucket. Since there will be a large loss of fry during the opening period, a large density is maintained at the beginning.

[0057] S202. One hundred million rotifers are placed in 10L of seawater, and a mother solution of inducing hormone A with a concentration of 100 μg / L is added to soak the rotifers, and the rotifers are slightly aerated to maintain the vitality of the rotifers. After soaking for 30 minutes, the rotifers are filtered and collected with a 500-mesh net; the rotifers are 9-15 days old and 100-200 μm in diameter; the newly hatched golden pomfret larvae in each bucket are fed with soaked rotifers every day from 3 days old (dph) until the larvae are 20 days old;

[0058] The method of feeding the aromatase inhibitor letrozole hormone to soak the rotifers has the advantage of being more gentle, that is, it can reduce the harm of androgens to young fish, has little stimulation to the organs of young golden pomfret, especially the digestive organs, and can effectively induce;

[0059] Two hours after feeding, check the feeding status of the juveniles under a microscope and adjust the number of rotifers fed according to the feeding status to ensure that they have consumed enough rotifers.

[0060] S203. Add the mother solution of inducing hormone A to the breeding feed to prepare compound feed A; the addition amount of letrozole hormone in compound feed A is 100 mg / kg, and the preparation method is to spray the mother solution of inducing hormone A evenly on the breeding feed by spraying, air-dry in a cool place for 24 hours, and store the prepared compound feed A at 4°C (the control group is sprayed with the same volume of 95% ethanol and air-dried); protect the hormone-treated feed from light when drying to avoid affecting the effect of letrozole;

[0061] Compound feed A was fed to golden pomfret fry aged 21 to 80 days every day, and the status of the golden pomfret fry was observed and tested at any time; compound feed A was fed three times a day at 8:00, 12:00 and 15:30 respectively. Golden pomfret swims fast and consumes a lot of water, and the daily feeding amount is 10% of its body weight; if conditions permit, fresh water was replaced every day to facilitate the growth and development of golden pomfret.

[0062] S3. Induction rearing of golden pomfret fry; specifically comprising the following sub-steps:

[0063] S301. The fry of golden pomfret are transferred to outdoor ponds for breeding, which is conducive to their faster growth;

[0064] S302. Add the mother solution of inducing hormone B to the breeding feed to prepare compound feed B; the addition amount of letrozole in compound feed B is 50 mg / kg, and the addition amount of 17α-methyltestosterone is 100 mg / kg, and the spray method is also adopted (refer to step S203); feed the compound feed B to the golden pomfret fry aged 81-120 days every day, and the feeding frequency is 2-3 times a day; observe and detect the status of the golden pomfret fry at any time.

[0065] S4. Male differentiation induction breeding of golden pomfret; specifically comprising the following sub-steps:

[0066] S401. The golden pomfret fry are transferred to the sea cages for breeding, making the environment more conducive to its growth and growing faster;

[0067] S402. The mother solution of inducing hormone C is added to the breeding feed to prepare compound feed C; the amount of 17α-methyltestosterone added to the compound feed C is 150 mg / kg, and the spray method is also used (refer to step S203); the compound feed C is fed to the golden pomfret aged 121-180 days every day, and the feeding frequency is 2-3 times a day; the state of the golden pomfret is observed and detected at any time;

[0068] S5. After the golden pomfret reaches 180 days of age, stop adding hormones to the feeding and feed it with breeding feed without hormones instead.

[0069] Example 2

[0070] This embodiment provides a method for cultivating artificially induced pseudo-male golden pomfret in batches, wherein:

[0071] The amount of letrozole hormone added in compound feed A is 100 mg / kg; the amount of letrozole added in compound feed B is 40 mg / kg, and the amount of 17α-methyltestosterone added is 120 mg / kg; the amount of 17α-methyltestosterone added in compound feed C is 150 mg / kg.

[0072] The remaining steps are the same as in Example 1.

[0073] Example 3

[0074] This embodiment provides a method for cultivating artificially induced pseudo-male golden pomfret in batches, wherein:

[0075] The concentration of the induction hormone A mother solution in step S202 is 150 μg / L;

[0076] The amount of letrozole hormone added in compound feed A is 80 mg / kg; the amount of letrozole added in compound feed B is 50 mg / kg, and the amount of 17α-methyltestosterone added is 100 mg / kg; the amount of 17α-methyltestosterone added in compound feed C is 180 mg / kg.

[0077] The remaining steps are the same as in Example 1.

[0078] Example 4

[0079] The KASP-based genotyping and identification experiment is as follows: Cultivate and induce pseudo-male golden pomfret according to the method of Example 1, 2 or 3; after feeding hormones for 180 days, collect golden pomfret fin samples, extract DNA to identify genetic sex, and calculate genetic sex ratio. Convert a SNP (Chr17:8325779) in the hsd17β1 gene into a sex-specific marker, and perform genotyping, i.e., KASP reaction, through competitive allele-specific PCR and high-resolution melting analysis to identify sex. This SNP is a sex-specific marker for golden pomfret. After ensuring that the quality of the extracted DNA genotyping test is qualified, read the genotype data of the golden pomfret sample, analyze the data, and then perform statistics according to the sample and site conditions to obtain the typing results of each sample, thereby determining the male and female typing of the sample. Use different fluorescent dyes to mark the two alleles, C / T for females (marked in green) and T / T for males (marked in blue). The results are as follows: Figure 1 As shown in the figure, among the 50 fish samples, 26 were genetically female (circled in the figure), 22 were genetically male (circled in the figure), and 2 were not detected, indicating that the pseudo-male golden pomfret was successfully cultivated.

[0080] Example 5

[0081] The histological sex identification of golden pomfret is specifically as follows: pseudo-male golden pomfret is bred and induced according to the method of Example 1, 2 or 3; after feeding hormones for 180 days, fin ray samples of golden pomfret are collected, and the physiological sex is identified after DNA extraction, and the physiological sex ratio is calculated.

[0082] The gonadal samples stored in the paraformaldehyde solution were taken out, and the gonadal tissues of appropriate size were cut and selected. The cut gonadal tissues were placed in gradient alcohol (50%, 70%, 80%, 95%, and 100%) for dehydration, and the dehydration time was 2h, 1h, 30min, 30min, and 30min, respectively. After dehydration, the tissue was transparently treated in a 1:1 mixture of xylene and alcohol for 2min30s. The tissue block after transparent treatment was translucent; then the tissue was placed in pure xylene for 1min, and the gonadal tissue became completely transparent. After that, the tissue was immersed in a 1:1 solution of xylene and paraffin in the embedding machine for 60min, and then transferred to a paraffin solution for wax immersion for 120min. After wax immersion, the tissue was fixed to the paraffin embedding bottom mold and paraffin embedding box, placed on a cold table for 20min, and after it was fully cooled, it was transferred to -20℃ for storage and sliced ​​24h later.

[0083] Before slicing, it is necessary to perform a wax trimming step. Use a knife to trim the paraffin block into a cube or cuboid of the appropriate size for the tissue. Fix the trimmed paraffin block in the microtome slot and adjust the slice thickness according to the size of the gonadal tissue. Since the gonadal tissue in this experiment is relatively thin, the slice thickness is 5 μm. Place the complete, continuous, curl-free paraffin slices in 39°C warm water for spreading. After the spreading is complete, place them on a slide and dry them in a 37°C oven for 20 hours.

[0084] After drying, hematoxylin-eosin staining (HE staining) was performed, including xylene dewaxing, gradient dehydration of ethanol and staining. After staining, the slices were dried and observed and photographed under an optical microscope at 100, 200, and 400 times the size.

[0085] The results are as follows Figure 2 As shown; among the 50 MT-treated fish sampled, 26 were genetically female as identified by kasp, of which 19 were found to have intersex female gonadal development by tissue section observation, accounting for 73% of genetic females; among the 50 MT-treated fish, 43 were physiologically intersex and physiologically male, with an induction rate of 86%.

[0086] Example 6

[0087] The method for breeding pseudo-male golden pomfret artificially induced in batches of the present invention can successfully breed pseudo-male golden pomfret. This embodiment provides an application example of breeding all-female golden pomfret seedlings using pseudo-male golden pomfret. The specific breeding method is as follows:

[0088] The pseudo-male golden pomfret obtained by hormone induction is selected as the backup parent; after it reaches sexual maturity, the pseudo-male golden pomfret parent (ZW♂) and the normal female fish parent (ZW♀) are used as the F0 generation original line parents for mating to obtain male (ZZ♂), female (ZW♀) and super-female (WW♀) offspring individuals; molecular biological technology is used to identify and screen out super-female individuals as backup parents for cultivation, and after sexual maturity, the super-female individuals are mated with normal males as F1 generation conversion line parents to obtain all-female golden pomfret seedlings (i.e., F2 generation female homozygous lines); the technical route is detailed in Figure 3 .

[0089] The key technical points of the present invention are as follows:

[0090] 1. Use letrozole for induction during the larval stage: The larval stage is in the early stages of gonadal development of golden pomfret, which is mainly the process of production, migration and differentiation of primordial germ cells. Feeding letrozole during this period can effectively inhibit the production of estrogen and make the gonadal differentiation direction develop towards males.

[0091] 2. Use letrozole and methyltestosterone combined induction in the juvenile stage: In the juvenile stage, it is a critical period for the differentiation of the gonads of golden pomfret. At this time, the use of letrozole and methyltestosterone mixed hormones can inhibit the production of estrogen on the one hand, and increase the androgen content in the body on the other hand, which can further promote the development of gonads towards males.

[0092] 3. Use methyltestosterone for induction in the juvenile stage: In the juvenile stage, the sexual differentiation of golden pomfret has been completed. The golden pomfret that has undergone early sex reversal to obtain pseudo-maleness needs to be maintained with androgens to keep its sex stable and prevent reversal.

[0093] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the disclosure of the present invention can be performed in parallel, sequentially or in different orders, as long as the desired results of the technical solution disclosed in the present invention can be achieved, and this document does not limit this.

[0094] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for cultivating artificially induced pseudo-male golden pomfret in batches, characterized in that: The specific steps include: S1. Prepare the mother solution of inducing hormone: weigh the aromatase inhibitor and dissolve it in an ethanol solution to obtain the mother solution of inducing hormone A; weigh the aromatase inhibitor and 17α-methyltestosterone hormone and dissolve them in an ethanol solution to obtain the mother solution of inducing hormone B; weigh the 17α-methyltestosterone hormone and dissolve it in an ethanol solution to obtain the mother solution of inducing hormone C; the aromatase inhibitor is letrozole hormone; S2. Induced rearing of newly hatched golden pomfret larvae with undifferentiated gonads; specifically comprising the following sub-steps: S201. In a recirculating aquaculture system, placing newly hatched golden pomfret fry with undifferentiated gonads; S202. soaking the rotifers in the mother solution of inducing hormone A for 20 to 40 minutes; feeding the soaked rotifers to the newly hatched golden pomfret larvae daily from the 3rd day of age until the larvae are 20 days old; S203. The mother solution of inducing hormone A is added to the breeding feed to prepare compound feed A; the compound feed A is fed to 21-80-day-old golden pomfret fry every day, and the state of the golden pomfret fry is observed and detected at any time; the amount of letrozole hormone added in the compound feed A is 80-120 mg / kg; S3. Induced rearing of golden pomfret fry: The golden pomfret fry were transferred to an outdoor pond for breeding; the mother solution of inducing hormone B was added to the breeding feed to prepare compound feed B; the compound feed B was fed to the golden pomfret fry aged 81-120 days every day, and the status of the golden pomfret fry was observed and detected at any time; the amount of letrozole added to the compound feed B was 40-60 mg / kg, and the amount of 17α-methyltestosterone added was 80-120 mg / kg; S4. Male differentiation induction breeding of golden pomfret: transfer golden pomfret fry to sea cages for breeding; add the mother solution of induction hormone C to the breeding feed to prepare compound feed C; feed compound feed C to golden pomfret aged 121-180 days every day, and observe and detect the status of golden pomfret at any time; the amount of 17α-methyltestosterone added in the compound feed C is 140-180 mg / kg; S5. After the golden pomfret reaches 180 days of age, stop adding hormones to the feeding and feed it with breeding feed without hormones instead.

2. The method for cultivating pseudo-male golden pomfret by artificial induction in batches according to claim 1, characterized in that: The concentration of the ethanol solution in step S1 is 95%.

3. The method for cultivating pseudo-male golden pomfret by artificial induction in batches according to claim 2, characterized in that: The concentration of the inducing hormone A mother solution is 50-150 μg / L.

4. The method for cultivating pseudo-male golden pomfret by artificial induction in batches according to claim 2, characterized in that: The concentration of the inducing hormone A mother solution is 100 μg / L; the soaking time of the rotifers in step S202 is 30 minutes, and the rotifers are 9-15 days old, with a diameter of 100-200 μm.

5. The method for cultivating pseudo-male golden pomfret by artificial induction in batches according to claim 4, characterized in that: The amount of letrozole hormone added in the compound feed A is 100 mg / kg; the amount of letrozole added in the compound feed B is 50 mg / kg, and the amount of 17α-methyltestosterone added is 100 mg / kg; the amount of 17α-methyltestosterone added in the compound feed C is 150 mg / kg.

6. The method for cultivating pseudo-male golden pomfret by artificial induction in batches according to claim 1, characterized in that: The diameter of the circulating aquaculture system is 1.5-2.5 m, and the water depth is 0.8-1.0 m.

7. The method for cultivating pseudo-male golden pomfret by artificial induction in batches according to claim 1, characterized in that: In the step S3 and step S4, the number of times of feeding the golden pomfret every day is 2-3 times.

8. Use of the method for breeding artificially induced pseudo-male golden pomfret in batches as claimed in any one of claims 1 to 7 in breeding pseudo-male golden pomfret.

9. Application of a method for breeding artificially induced pseudo-male golden pomfret in batches according to any one of claims 1 to 7 in breeding all-female golden pomfret seedlings, characterized in that: The pseudo-male golden pomfret cultivated was used as the parent F0 generation for mating with the normal female golden pomfret, and after obtaining the offspring, the super-female golden pomfret was selected as the parent F1 generation; the super-female golden pomfret was mated with the normal male golden pomfret parent to obtain the all-female golden pomfret seedlings.

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