Method for nursing mandarin fish parent fish before and after artificial spawning induction

Abstract

The invention discloses a nursing method before and after artificial spawning induction of parent mandarin fish, which comprises the following steps: nursing after collection of wild mandarin fish: selecting healthy, disease-free and residue-free fish, carrying out aeration transfer with water in a sorting box, controlling the temperature difference between water temperatures before and after transfer not to exceed 5 DEG C, soaking in a bag for over-temperature, soaking in saline water, and putting the wild mandarin fish into a 1: 1 filtered circulating water system; the steps of disinfection, pest killing, sterilization and bacteriostasis are alternately carried out, the ingestion condition, the swimming capacity and the clustering condition of the mandarin fish are observed, sampling microscopic examination observation is carried out, and if all conditions are normal and do not have parasitic diseases or bacterial infection, nursing work after the wild mandarin fish is collected is completed. The method further comprises the steps of prenatal breeding of mandarin fish, spawning induction, egg squeezing, postnatal breeding of parent fish and disease control, the survival rate of the wild mandarin fish after collection is improved in multiple aspects, breed conservation and breeding work of the wild mandarin fish is facilitated, the survival rate of the parent fish of the mandarin fish reaches 80% or above, and the method plays an important role in breeding of excellent new varieties which grow fast and are high in stress resistance.

Description

Technical Field

[0001] The invention relates to the technical field of mandarin fish breeding, and in particular to a method for nurturing mandarin fish broodstock before and after artificial induction of spawning. Background Art

[0002] Siniperca chuatsi, also known as mandarin fish, mandarin fish and seasonal fish, belongs to the order Perciformes, family Percichthyidae, genus Siniperca, and is an important freshwater aquaculture species in my country. At present, my country's Siniperca chuatsi industry has broad development prospects, but it still faces many problems in breeding. Long-term inbreeding has led to obvious germplasm degradation in farmed Siniperca chuatsi, which is mainly manifested in reduced growth rate, decreased disease resistance and stress resistance, which has seriously restricted the sustainable and healthy development of Siniperca chuatsi aquaculture industry.

[0003] It was also found that during the breeding process of mandarin fish, the loss of mandarin fish broodstock after spawning was large, resulting in dystocia, namely "mandarin fish spawning syndrome", which increased the difficulty of native mandarin fish conservation, population expansion and breeding. The main reasons are: the lack of care technology for wild mandarin fish after collection, the lack of post-birth broodstock care technology, the lack of early and delayed breeding broodstock breeding environment regulation technology, the lack of technical specifications for induction of spawning and squeezing eggs, the lack of standardization of broodstock sources, and the unevenness and poor repeatability of existing disease prevention and control technologies.

[0004] It can be seen from this that how to improve the survival rate of mandarin fish broodstock, especially for the conservation of indigenous mandarin fish, to achieve the breeding of good varieties of mandarin fish, and to cultivate new excellent varieties with fast growth and strong resistance, has become a goal that the industry urgently needs to improve. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for the conservation of mandarin fish broodstock before and after artificial induction of spawning, so as to improve the survival rate of mandarin fish broodstock, realize the breeding of fine varieties of mandarin fish, cultivate new fine varieties with fast growth and strong stress resistance, thereby overcoming the shortcomings existing in the existing mandarin fish breeding process.

[0006] In order to solve the above technical problems, the present invention provides a method for the conservation of mandarin fish broodstock before and after artificial induction of spawning, the method comprising the steps of nursing wild mandarin fish after collection: selecting healthy, disease-free and non-disabled fish at the wild mandarin fish catching site for transportation in a sorting box with water aeration, measuring the water temperature of the water area before transportation, adjusting the water temperature after arriving at the destination, with the temperature difference not exceeding 5°C, packing the fish, soaking the fish in a bag for overheating, and soaking in salt water, and then putting the wild mandarin fish into a 1:1 filtered circulating water system; adding iodine disinfectant, adding insecticide the next day, putting palatable bait fish after 3 days, and treating the bait fish with enrofloxacin by gavage after being soaked in salt water, repeating the above disinfection-insecticide-bactericidal / bacteriostatic steps alternately for 1-2 times, observing the feeding situation, swimming ability and clustering situation of the mandarin fish and sampling for microscopic observation, and if everything is normal and there is no parasitic disease or bacterial infection, the nursing work of the wild mandarin fish after collection is completed.

[0007] As a further improvement, the iodine disinfectant is povidone-iodine solution, and the insecticide is tobendazole solution and terpenoids.

[0008] As a further improvement, the bait fish is a scaly fish which swims slowly, has no hard spines, is slender, and has a body length of 1 / 3-1 / 2 of the body length of a mandarin fish.

[0009] The method is further improved, and further comprises the step of pre-natal cultivation of mandarin fish: selecting mandarin fish with a strong physique, no injuries on the body surface, and a fat body as broodstock, selecting female broodstock of 1.5-2.0 kg at the age of 3, and selecting male broodstock of 1.0 kg or more at the age of 2; cultivating mandarin fish broodstock in a system of 1:2 between the filtering pool and the breeding pool, and providing scale fish with a slow swimming speed, no hard spines, slender body, and a body length of 1 / 3-1 / 2 of the body length of mandarin fish as bait fish; and installing outer edge waterway pipes on the side walls and bottom of the breeding pool, adjusting the water temperature through the outer edge waterway pipes according to the needs of early breeding or delayed breeding of mandarin fish, and regularly replenishing the circulating water with micro-water flow and regularly measuring the water quality.

[0010] As a further improvement, when the mandarin fish needs to be bred in advance, the water is heated through the outer edge waterway pipe and the waterway running time is controlled to make the system water temperature reach 20-25°C; when the mandarin fish needs to be delayed in breeding, low-temperature water is added through the outer edge waterway pipe and the waterway running time is controlled to control the system water temperature within 20°C.

[0011] Further improved, the method also includes an induction of labor step: after the mandarin fish pre-natal cultivation step, female broodstock with a swollen, soft and elastic abdomen, a concave midline of the abdomen, and eggs flowing out when lightly pressed, and male broodstock with milky white semen flowing out when lightly pressed are selected for artificial induction of labor; the mandarin fish broodstock are transferred to a spawning pond one day before induction of labor, and the temperature difference of the water before and after the transfer is controlled at ±2°C. During the induction of labor, oxytocin is injected into the base of the pectoral fin, the injection volume is within 5mL, the depth of the induction of labor needle is 1.5cm, and the breeding water temperature is controlled at 24-26°C; after induction of labor, the female mandarin fish and the male mandarin fish are paired in a ratio of 1:1.5, and placed in a simple loop for water flow stimulation to promote natural spawning.

[0012] As a further improvement, the oxytocin is injected with one injection of DOM: 10 mg / kg, LRH-A2: 10 μg / kg, and HCG: 1000 IU / kg to female broodstock, and the injection of male broodstock is reduced by half.

[0013] The inducing spawning step further comprises an artificial egg squeezing step, specifically: controlling the water temperature in the loop to be 26°C, checking the rear-end collision of the parent fish every hour after 22 hours of the end of the inducing spawning, and if rear-end collision is found, fishing out the female parent fish and squeezing the eggs; blocking the reproductive opening of the female parent fish when fishing out the fish, and when squeezing the eggs, one person holds the fish with a dry towel, and the other person uses both palms to massage and squeeze from the abdomen of the female parent fish toward the reproductive opening, and stopping squeezing the eggs when blood clots appear.

[0014] As a further improvement, the method further comprises a postpartum care step: injecting potassium penicillin for injection into the base of the pectoral fin of the postpartum broodstock at a dosage of 50,000 units per kilogram, packing the fish, measuring the water temperature of the spawning pond, adjusting the temperature of the 1:1 filtered circulating water system in advance, with a temperature difference of no more than 3°C, placing the fish in a 1:1 filtered circulating water system after superheating with a bubble bag and soaking in salt water, adding iodine disinfectants, adding insecticides the next day, placing palatable bait fish three days later, and treating the bait fish with enrofloxacin by gavage, repeating the above disinfection-insecticide-bactericidal / bacteriostatic steps alternately 1-2 times, regularly checking the feeding situation of the mandarin fish, and taking samples for microscopic examination if they are not eating, floating, or out of the group. If everything is normal and there is no parasitic disease, bacterial infection, etc., the fish are transferred to a 1:2 system of the filtration pool and the breeding pool for continued cultivation in preparation for the next round of induced spawning.

[0015] As a further improvement, the method also includes the steps of disease prevention and control: for wheelworm disease, copper sulfate and trichlorfon are used for treatment; for dactylariasis, trichlorfon and tobendazole solution are used in combination with artemisia annua powder hanging bags for treatment; for ichthyophthirius disease, new effective mefenamic acid is used for treatment; for bacterial infection, enrofloxacin is used for oral treatment; for saprolegniasis in low-temperature aquaculture water, allicin is used for prevention and salicylic acid for treatment; for fish mullet disease and anchorfish disease, trichlorfon and "anchorfish killer" are used for regular pest control according to the life history of the parasites.

[0016] After adopting such a design, the present invention has at least the following advantages:

[0017] The method for pre- and post-artificial induction of broodstock of mandarin fish of the present invention improves key technologies such as post-collection care of wild mandarin fish, pre-birth breeding of mandarin fish, induction of spawning, squeezing eggs, post-birth breeding of broodstock and disease prevention, thereby greatly improving the survival rate of wild mandarin fish after collection, and achieving a survival rate of more than 80% in the post-collection care stage of wild mandarin fish; it is also beneficial to the smooth progress of seed conservation and excellent variety breeding of wild mandarin fish, and reduces the injury of broodstock during egg squeezing; and after the post-birth care step, the survival rate of mandarin fish broodstock is still more than 80%, which truly and effectively improves the survival rate and seed conservation of wild mandarin fish, and plays an important role in breeding an excellent new variety of mandarin fish with fast growth and strong stress resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0019] Figure 1 The invention is a flowchart of a method for the conservation of mandarin fish broodstock before and after artificial induced spawning. DETAILED DESCRIPTION

[0020] The Hebei Fauna - Fishes records that there are Siniperca chuatsi in Jixian County, Tianjin, Huairou, Beijing, Baiyangdian, Hebei, Daqing River and Ziya River. However, in recent years, Siniperca chuatsi resources have been seriously threatened, and the problems of sharp decline in wild germplasm resources, germplasm degradation, decreased growth and stress resistance of Siniperca chuatsi have become more and more serious. Therefore, it is particularly important to collect, preserve seeds and cultivate seedlings of indigenous Siniperca chuatsi in the Beijing-Tianjin-Hebei region. This embodiment is to select wild Siniperca chuatsi in the Beijing-Tianjin-Hebei region for conservation work before and after artificial induction of spawning, and achieved good results. The specific embodiments are as follows.

[0021] Refer to the attached Figure 1 As shown, this embodiment is directed to a method for the conservation of mandarin fish broodstock before and after artificial induction of spawning in the Beijing-Tianjin-Hebei region, and the steps are as follows:

[0022] Step 1: Care after collecting wild mandarin fish:

[0023] Wild mandarin fish were collected during the non-banned fishing season. At the fishing site, healthy, disease-free and non-diseased fish were selected for transportation in sorting boxes with water aeration. The water temperature was measured before transportation. After arriving at the destination, the water temperature was adjusted so that the temperature difference did not exceed 5°C. The fish were packed, soaked in the bags for 15 minutes, and immersed in salt water. They were placed in a 1:1 filtered circulating water system. Povidone iodine was added for disinfection. Tobacco solution and terbinazone were added the next day. Three days later, palatable bait fish were added. The bait fish were immersed in salt water for 15 minutes and then gavaged with enrofloxacin. The above disinfection-insecticide-bactericidal / antibacterial steps were repeated alternately once. After one week of temporary rearing, the feeding situation, swimming ability, grouping situation of the mandarin fish were observed, and the sampling and microscopic observation were carried out. If everything was normal and there was no parasitic disease or bacterial infection, the wild mandarin fish were transferred to the mandarin fish broodstock intensive breeding pond for further breeding.

[0024] The disinfectant povidone-iodine solution may also be replaced by other iodine disinfectants or other salt disinfectants. For water bodies with high alkalinity and hardness and a temperature above 20°C, 1 ppm trichlorfon may also be used as an insecticide.

[0025] The bait fish is a scaled fish that swims slowly, has no hard spines, is slender, and has a body length of 1 / 3-1 / 2 of that of the mandarin fish, such as crucian carp, four major carps, dace, eliminated goldfish, koi, etc., all of which can be used as bait fish for the mandarin fish.

[0026] Through this method, the survival rate of wild mandarin fish collected can reach over 80%.

[0027] Step 2: Prenatal training of mandarin fish:

[0028] Selection of broodstock: Female broodstock should be 3 years old and weigh 1.5-2.0 kg, and male broodstock should be 2 years old and weigh more than 1.0 kg. They should be strong, have no injuries on the body, and be plump.

[0029] Parent fish cultivation: Mandarin fish are cultivated in a circulating water system with a ratio of 1:2 between the filter pool and the breeding pool. Scaly fish with slow swimming speed, no hard spines, slender body, and body length of 1 / 3-1 / 2 of mandarin fish are given as bait fish. The circulating water is regularly replenished with micro-flow and the water quality is regularly measured. When the concentration of ammonia nitrogen and nitrite nitrogen in the water body is higher than 0.6mg / L and 0.05mg / L respectively, the bottom sewage needs to be discharged and 1 / 3 of the water needs to be replaced, which is conducive to maintaining a stable growth environment. The filter tank is cleaned once every 1-2 months.

[0030] In addition, an outer waterway pipe is installed on the side wall and the bottom of the breeding pond, and then the water temperature of the circulating water body is adjusted through the outer waterway pipe according to the actual needs of early breeding or delayed breeding of mandarin fish, so as to achieve early breeding or delayed breeding of mandarin fish. If early breeding is required, water is heated and the waterway operation time is controlled through the outer waterway pipe to make the system water temperature reach 20-25°C, so as to achieve early breeding of parent fish; if delayed breeding is required, low-temperature water is added through the outer waterway pipe and the waterway operation time is controlled to make the system water temperature reach within 20°C, which can effectively extend the breeding time of mandarin fish and achieve delayed breeding of parent fish.

[0031] Step 3: Inducing labor:

[0032] Select female broodstock with a swollen, soft and elastic abdomen, a concave midline, and eggs flowing out when pressed lightly, and male broodstock with milky white semen flowing out when pressed lightly for artificial induction of spawning.

[0033] The broodstock were transferred to the spawning pond one day in advance, and the temperature difference before and after the transfer was controlled at ±2℃. The oxytocin for female broodstock was 10mg / kg of domperidone for injection (DOM), 10μg / kg of luteinizing hormone-releasing hormone for injection (LRH-A2), and 1000IU / kg of human chorionic gonadotropin for injection (HCG), and the injection was halved for male broodstock. The injection was injected at the base of the pectoral fin, with an injection volume of less than 5mL and a needle depth of 1.5cm to avoid injuring the heart too deeply. The most suitable water temperature for breeding is 24-26℃. After induced spawning, the female and male mandarin fish were paired in a ratio of 1:1.5, placed in a simple loop, and stimulated by running water to promote natural spawning. If artificial egg squeezing is used, the water temperature should be controlled at around 26℃ so that the spawning time of each group of mandarin fish tends to be synchronized and the egg maturation time in the ovaries of the same fish is relatively concentrated.

[0034] Step 4: Egg squeezing:

[0035] 22 hours after the end of induced spawning, check the broodstock every hour for tail-chasing. If any tail-chasing is found, remove the female broodstock and start squeezing the eggs.

[0036] When catching fish, use fingers to block the reproductive hole of female parent fish to prevent the loss of eggs, and use a dry towel to wipe the surface of the fish dry. When squeezing eggs, two people work together, one person holds the fish with a dry towel, and places the fish horizontally (remember not to squeeze eggs with the head up and the tail down, which can easily cause immature eggs to block the reproductive hole, ovarian eversion, and mature eggs cannot be squeezed out due to blocked passages), and one person uses both palms to massage and squeeze from the abdomen toward the reproductive hole, and stops squeezing eggs when blood clots appear. This method effectively increases the contact area between the palm and the fish's abdomen, avoids uneven force on the ovaries, and repeated squeezing of eggs; it also avoids squeezing eggs with one hand, where the thumb and palm are separated on both sides, and uneven force causes internal injuries to the mandarin fish.

[0037] Step 5: Postpartum care:

[0038] For postpartum broodstock, injectable penicillin potassium solution at the base of the pectoral fin, with a dosage of 50,000 units per kilogram (penicillin potassium for injection is dissolved and diluted with injectable saline). Measure the water temperature of the spawning pond, adjust the temperature of the 1:1 filtered circulating water system in advance, and the temperature difference should not exceed 3°C. Pack the fish, soak the bags for 15 minutes, soak them in salt water, and put them into the 1:1 filtered circulating water system. Add povidone iodine to disinfect the system, add tobendazole solution and terfenadine the next day, and add palatable bait fish (bait fish are treated with enrofloxacin after being soaked in salt water for 15 minutes) after 3 days. Repeat the above disinfection-insecticide-bactericidal / bacteriostatic steps alternately once. After 2 weeks of temporary rearing, observe the feeding situation, swimming ability, clustering situation of the mandarin fish, and observe the sampling microscopy. If everything is normal and there is no parasitic disease or bacterial infection, transfer it to the 1:2 system of the filtration pool and the breeding pool for continued cultivation to prepare for the next round of artificial induction of birth.

[0039] After completing this postpartum care step, the survival rate of postpartum mandarin fish broodstock can reach more than 80%.

[0040] Step 6: Disease prevention and control:

[0041] Disease control is always prevention-oriented in the whole method of artificial induction of broodstock of mandarin fish. For example, before and after the transfer of broodstock, the above disinfection-insecticide-bactericidal / bacteriostatic operation steps should be carried out, that is, the breeding pond is disinfected, the bubble bag is heated, the salt water is immersed, and it is placed in a 1:1 filtered circulating water system, and povidone iodine is added for disinfection. The next day, tobendazole solution and terfenadine are added respectively. After 3 days, palatable bait fish are put in. The bait fish are immersed in salt water for 15 minutes and then gavage with enrofloxacin. The above disinfection-insecticide-bactericidal / bacteriostatic steps are repeated alternately 1-2 times according to the actual situation.

[0042] It is also necessary to regularly check the feeding situation of mandarin fish broodstock. If they do not eat, float, or leave the group, take samples for microscopic examination. If trichodinasis is found, copper sulfate and trichlorfon are used for treatment; if dactylariasis is found, trichlorfon and tobendazole solution (for aquaculture) are used in combination with artemisia annua powder for hanging tape treatment; if Ichthyophthirius is found, new effective mefenamic acid is used for treatment; if bacterial infection is found, enrofloxacin is used for oral treatment; if saprolegniasis is found in low-temperature aquaculture water, allicin is used for prevention and salicylic acid for treatment. If fish mullet disease and anchor mullet disease are found, regular deworming is carried out according to the life history of the parasites, mainly using trichlorfon and "anchor mullet killer" for treatment, so as to achieve the effect of early detection and early treatment.

[0043] Of course, the conservation method of mandarin fish broodstock before and after artificial induction of spawning can also be used for wild mandarin fish conservation in other regions, effectively improving the survival rate and seed conservation of wild mandarin fish, and is of great significance for breeding a new variety of mandarin fish that grows fast and has strong resistance to adversity.

[0044] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Those skilled in the art may make some simple modifications, equivalent changes or modifications using the technical contents disclosed above, which all fall within the protection scope of the present invention.

Claims

1. A method for the conservation of mandarin fish broodstock before and after artificial induction of spawning, characterized in that: The method comprises the following steps of post-collection care of wild mandarin fish: At the wild mandarin fish catching site, healthy, disease-free and intact fish are selected for transportation in boxes with water and aeration. The water temperature is measured before transportation. After arriving at the destination, the water temperature is adjusted, and the temperature difference does not exceed 5°C. The fish are packed, soaked in warm water, and then placed in a 1:1 filtered circulating water system. Iodine disinfectant was added, and insecticide was added the next day. After 3 days, palatable bait fish was put in. The bait fish was treated with enrofloxacin by gavage after being immersed in salt water. The above disinfection-insecticide-bactericidal / bacteriostatic steps were repeated alternately 1-2 times, and the feeding situation, swimming ability, and aggregation situation of the mandarin fish were observed. The sampling was observed under a microscopic microscope. If everything was normal and there was no parasitic disease or bacterial infection, the care work for the wild mandarin fish after collection was completed.

2. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 1, characterized in that: The iodine disinfectant is povidone-iodine solution, and the insecticide is mebendazole solution and terpenoid.

3. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 1, characterized in that: The bait fish is a scaly fish which swims slowly, has no hard spines, is slender, and has a body length of 1 / 3 to 1 / 2 of the body length of a mandarin fish.

4. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 1, characterized in that: The method also includes the step of pre-natal cultivation of mandarin fish: Select healthy, uninjured, and plump mandarin fish as broodstock. Female broodstock are 3-year-old and 1.5-2.0 kg, and male broodstock are 2-year-old and over 1.0 kg. Mandarin fish broodstock are cultivated in a system of 1:2 between a filtration pond and a breeding pond, and scaly fish that swim slowly, have no hard spines, are slender, and are 1 / 3-1 / 2 the length of mandarin fish are given as bait fish; and peripheral waterway pipes are installed on the side walls and the bottom of the breeding pond. According to the needs of early or delayed breeding of mandarin fish, the water temperature is adjusted through the peripheral waterway pipes, and the circulating water is regularly replenished with micro-flow water and the water quality is regularly measured.

5. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 4, characterized in that: When the mandarin fish needs to be bred in advance, the water is heated through the outer edge waterway pipeline and the waterway running time is controlled to make the system water temperature reach 20-25°C; when the mandarin fish needs to be bred later, low-temperature water is added through the outer edge waterway pipeline and the waterway running time is controlled to make the system water temperature within 20°C.

6. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 4, characterized in that: The method further comprises the step of inducing labor: After the pre-natal cultivation steps of mandarin fish, female broodstock with swollen, soft and elastic abdomen, concave midline abdomen, and eggs flowing out when lightly pressed, and male broodstock with milky white semen flowing out when lightly pressed are selected for artificial induced spawning; The mandarin fish broodstock are transferred to the spawning pond one day before induction of spawning. The water temperature difference before and after the transfer is controlled at ±2℃. Oxytocin is injected at the base of the pectoral fin during induction of spawning. The injection volume is within 5mL, the needle insertion depth is 1.5cm, and the breeding water temperature is controlled at 24-26℃. After induction of spawning, the female mandarin fish and the male mandarin fish are paired in a ratio of 1:1.5 and placed in a simple loop for water flow stimulation to induce natural spawning.

7. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 6, characterized in that: The oxytocin is injected with one injection of DOM: 10 mg / kg, LRH-A2: 10 μg / kg, and HCG: 1000 IU / kg to female broodstock, and half the injection is given to male broodstock.

8. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 7, characterized in that: The inducing labor step also includes an artificial egg squeezing step, specifically: The water temperature in the control loop was 26℃. After 22 hours of induced spawning, the broodstock were checked every 1 hour for rear-end collision. If any rear-end collision was found, the female broodstock should be removed and the eggs squeezed. The reproductive pores of the female broodstock should be blocked when the fish were removed. When squeezing the eggs, one person held the fish with a dry towel, and the other person used both palms to massage and push from the abdomen of the female broodstock toward the reproductive pore. When blood clots appeared, squeezing the eggs stopped.

9. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to claim 8, characterized in that: The method further comprises the step of postpartum care: The postpartum broodstock were injected with potassium penicillin at the base of the pectoral fin at a dosage of 50,000 units per kilogram. The fish were packed and the water temperature of the spawning pond was measured. The temperature of the 1:1 filtered circulating water system was adjusted in advance with a temperature difference of no more than 3°C. After being superheated with a bubble bag and immersed in salt water, the fish were placed in a 1:1 filtered circulating water system and iodine disinfectants were added. Insecticides were added the next day. After 3 days, palatable bait fish were added and the bait fish were treated with enrofloxacin by gavage. The above disinfection-insecticide-bactericidal / inhibitory steps were repeated alternately 1-2 times. The feeding situation of the mandarin fish was checked regularly. If the fish were not eating, floating on the surface or out of the group, samples were taken for microscopic observation. If everything was normal and there was no parasitic disease or bacterial infection, the fish were transferred to a 1:2 system of the filtration pool and the breeding pool for continued cultivation in preparation for the next round of induced spawning.

10. The method for pre- and post-artificial induction of spawning of mandarin fish broodstock according to any one of claims 1 to 9, characterized in that: The method also includes the disease control step: For trichodinasis, copper sulfate and trichodina are used for treatment; For dactylariasis, use trichlorfon, mebendazole solution and artemisia annua powder hanging bags for treatment; For Ichthyophthirius trichoderma, use the new effective melon-killing agent for treatment; For bacterial infections, enrofloxacin is used orally; For Saprolegniasis in low-temperature aquaculture water, allicin is used for prevention and salicylic acid for treatment; For fish mullet disease and anchor mullet disease, use trichlorfon and "anchor mullet killer" to regularly kill insects according to the life history of the parasites.

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