A method for artificially breeding long-filament fish

Abstract

The invention discloses an artificial breeding method for long-threaded fish, which comprises the following breeding steps: step one: heat preservation, feeding, flushing to strengthen the cultivation of broodstock, and determine the date to ripen the broodstock. Step two: select broodstock to be born one month later. Step three: injection of oxytocin and running water to stimulate spawning and fertilization of broodstock. Step four: eggs are laid out and hatching conditions are controlled by a semi-submersible hatching device, and placed in a pool water body for hatching. Step five: within 36-48 hours after the fry emerges from the membrane, the fry swims horizontally and opens its mouth, and begins to feed rotifers in the hatching pool or cultivate in a pond. This artificial breeding method creates its large-scale breeding technology according to the reproductive biological characteristics of the long-threaded fish itself, breaks through the technical bottleneck of artificial breeding of domestic long-threaded fish, has a high breeding success rate, obtains artificial seedlings that continue the reproduction of its population, and then effectively maintains the ecological balance of natural waters and protects the rare and endangered aquatic germplasm resources.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, in particular to an artificial breeding method for long-thread fish. Background Art

[0002] Long-filament fish mango Pangasiussanitwongsei ) is a large subtropical migratory fish, also known as Genghis Khan fish, native to the Chao Phraya River and Mekong River basins. In my country, it is only found in Xishuangbanna area in the lower reaches of the Lancang River. It is an aquatic species with high economic and scientific research value.

[0003] In order to maintain the ecological balance of natural waters and protect rare aquatic germplasm resources, it is necessary to artificially breed long-filamented sharks. The closest existing technology is the artificial breeding and seedling raising method of Su's round-bellied shark (common name: freshwater shark). The artificial breeding and seedling raising method of Su's round-bellied shark mainly involves introducing Malaysian Su's round-bellied shark species to cultivate broodstock, then artificially ripening and induced production with ripening and induced production drugs to obtain fish eggs, and then hatching and cultivating the fish eggs to finally obtain seedlings for aquaculture production.

[0004] Through actual production research, it was found that although the long-threaded fish mantis and the Su's round-bellied fish mantis belong to the same family of fish, there are species differences between them, and there are also huge differences in reproductive biological characteristics. The long-threaded fish mantis cannot be successfully propagated using the Su's round-bellied fish mantis. Therefore, it is necessary to develop an artificial breeding method for the long-threaded fish mantis. Summary of the invention

[0005] The purpose of the present invention is to provide an artificial breeding method for long-thread fish mantis, which creates a large-scale breeding technology based on the reproductive biological characteristics of the long-thread fish mantis, breaks through the technical bottleneck of domestic artificial breeding of long-thread fish mantis, has a high breeding success rate, and obtains artificial seedlings that continue the reproduction of its population, thereby effectively maintaining the ecological balance of natural waters and protecting the rare and endangered aquatic germplasm resources.

[0006] In order to achieve the purpose of the present invention, the technical solution adopted is:

[0007] An artificial breeding method for long-filament fish tang, comprising the following breeding steps:

[0008] Step 1: Cultivation and ripening: In a pond with a water temperature above 20℃ and a water depth of more than 2.5 meters, carry out intensive cultivation of adult individuals of long-thread fish over 6 years old.

[0009] Step 2: Selection of fish to be born: One month after the ripening date, squeeze the milky white semen that flows out of the cloaca of the long-threaded fish by hand and disperse it into the water. Use electron microscopy equipment to measure the sperm motility in the semen diluted 100 times, that is, select more than 5 sperm passing through the center of the same visual field in 1 minute as the standard to select male fish to be born, so as to ensure the effective sperm production and fertilization rate of male fish; when selecting female fish, select female fish with soft and swollen abdomen and visible ovarian groove on the back abdomen, and select broodstock whose ovaries have most of the eggs reaching mature egg diameter as female fish to be born. The selection is assisted by a handheld digital ultrasonic detector after anesthesia. The ovaries are explored by a digital ultrasonic detector, and female fish with more than 80% of the eggs with an egg diameter of more than 1.8 mm are selected to induce labor, so as to ensure the effective egg production and fertilization rate of female fish; MS-222 food-grade anesthetic is used for anesthesia. It is diluted with water at a dosage of 250 grams / cubic meter to soak and anesthetize the female and male fish to be born to prevent damage caused by violent swinging of the fish body.

[0010] Step 3: Injection for induction of labor: For female fish to be born, mix the dosage of LRH-A2, DOM, and HCG in the scaleless fish induction instructions, add 0.45% saline to prepare a solution and inject it into the fish body cavity twice. The first injection dosage is 1 / 3 of the total mixed dosage. After an interval of 10-12 hours, the remaining 2 / 3 dosage is injected for the second time. The injection volume of each female fish is 1.5-2 ml; the injection dosage of male fish to be born is 1 / 3-1 / 2 of that of the female fish to be born, synchronized with the second injection time of the female fish, and completed at one time. The injection volume of each male fish is 1.0-1.5 ml. The needle is pointed toward the head of the fish, at a 45-degree angle to the fish body axis, and the needle is inserted from the base of the pectoral fin to a depth of 1 cm to push the solution to ensure The liquid medicine accurately and in sufficient quantity enters the fish body cavity to exert the expected effect. The method of injecting the ripening and expediting liquid medicine into the fish body cavity ensures that the medicine is effectively absorbed by the fish body and fully exerts its efficacy. The parent fish injected with the medicine are placed in a pool together, and a water pump is used to form an internal circulation of the pool water, maintaining the water temperature at 25 degrees Celsius, the water flow rate at 0.05 m / s, and the dissolved oxygen in the water body above the standard of 5 mg / L. After the effective period, the female fish and male fish are caught in a ratio of 1:1. After wiping the water on the surface of the fish with a dry towel, the fish eggs and semen are quickly squeezed into a large dry container. While squeezing the sperm and eggs, stir them with the main wing feathers of the goose. After squeezing the sperm and eggs, add an appropriate amount of water and stir for fertilization for 10-15 seconds, and then use a semi-submersible incubator to lay eggs. LRH-A2 is ovulation hormone No. 2, DOM is dioconazole maleate, and HCG is injectable chorionic gonadotropin, which are purchased from the market.

[0011] Step 4: Incubation of fish eggs: Place the semi-submersible incubator in the water body of the pool for incubation. Specifically, the fertilized fish eggs are laid on a mesh with a specification of 40×60 cm through the semi-submersible incubator, and are suspended in a water depth of 1 meter and an area of ​​15 square meters. The number of meshes is controlled within 40 pieces, the incubation water temperature is controlled at 23-28 degrees Celsius, the dissolved oxygen is maintained at more than 5 mg / L, the pH value is 6.8-7.2, the amount of new water for incubation is maintained at more than 0.5 cubic meters / hour, the amount of water replacement is appropriately increased when the fry emerges from the membrane, and the drain outlet of the incubation pool is wrapped with 80-mesh polyethylene mesh; after all the fry emerge from the membrane, the incubation mesh is removed in time to prevent the egg membrane on the mesh from decomposing and polluting the water quality. The preferred application number of the semi-submersible incubator is 201620776700.4, and the name is the patented technology of the semi-submersible sticky fish egg universal incubator.

[0012] Step 5: Fry cultivation: The fry will swim open within 36-48 hours after hatching, and then be fed with rotifers in the hatching pond or cultivated in the pond.

[0013] Further preferred: in step 1, the cultivation and ripening is also carried out by accumulating the daily average water temperature to determine the injection date for ripening female fish, that is, starting from January 1 of each year, the cumulative daily average water temperature reaches 3700 degrees Celsius to determine the ripening date of female fish in that year, and the dosage of 0.5 micrograms / kg of fish body weight is adjusted according to the instructions for use. 0.45% physiological saline is added to make a liquid medicine, and LRH-A3 is injected into the body cavity of the female fish. The amount of liquid medicine injected for each female fish is 1.0-1.5 ml.

[0014] Further preferably, the injection of LRH-A3 into the body cavity of the female fish is performed by injecting at the base of the pectoral fin, and the injection site is gently rubbed for 1-2 seconds immediately after injection to prevent the drug solution from leaking out of the body. LRH-A3 is ovulation hormone No. 3, which is commercially available.

[0015] Further preferred method: in step 1, the fish are fed with forktail fish feed with a protein content of 35-38% at a rate of 5% of the fish body weight twice a day, a compound multivitamin rich in vitamin E is mixed in two days a week, and a water pump or a submersible aerator is used to form an internal circulation in the pond water to stimulate the gonadal development of the broodstock.

[0016] Further preferred: the goose main wing feather bundle is made of 5-8 main wing feathers gathered and bundled together, and the feather shafts and barbs are radiated outward. The egg density is controlled by quickly sticking the fertilized eggs with the goose main wing feather bundle, so that the eggs attached to the hatching mesh are spaced 2 mm apart and not stuck to each other, ensuring that the effects of water mold and oxygen consumption are effectively reduced.

[0017] Further preferred: the rotifers are fed regularly in the pool every morning and afternoon, and the feeding amount is adjusted in time according to the survival of the rotifers in the water body half an hour after feeding. When the fry reaches 1.5 cm, the powder feed with 42% protein is gradually added and the rotifers are stopped until the fingerling stage, and the particle size of the feed is determined according to the fish caliber. A 200-mesh polyethylene scoop is used to carry water to feed the fry and rotifers, and at the same time, combined with the microphotographic sampling observation method, the number of fry per cubic meter of water in the nursery pool is controlled to be less than 10,000, and the number of live bait individuals fed is more than 10 times the number of fry, to ensure that the early cannibalism rate of the fry is effectively reduced.

[0018] Further preferred: the pond cultivation is to use algae seeds and fertilizer paste to cultivate good water quality 3-5 days in advance, and choose a period of sunny weather and water temperature of about 26°C to put the fry into the pond; after the fry are put into the pond, fertilizer paste and microecological preparations are regularly added to regulate the plankton in the pond water body, and when the fry reach 1.5 cm, start feeding powder feed with 42% protein, and gradually adjust the feeding of feed with appropriate particle size according to the caliber of the fish throughout the entire fish seed cultivation stage.

[0019] The artificial breeding method of the long-thread fish mantis mainly creates a large-scale breeding technology according to the reproductive biological characteristics of the long-thread fish mantis itself during the stages of broodstock ripening, selection, spawning, fish egg hatching and seedling cultivation, breaks through the technical bottleneck of domestic long-thread fish mantis artificial breeding, has a high breeding success rate, and obtains artificial seedlings to continue the reproduction of its population, thereby effectively maintaining the ecological balance of natural waters and protecting this rare and endangered aquatic germplasm resource. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a flow chart of the artificial breeding of long-thread fish Mansonia in the stages of broodstock ripening, selection, induction of spawning, egg hatching and seedling cultivation. It mainly creates large-scale breeding technology based on the reproductive biological characteristics of long-thread fish Mansonia in the stages, breaks through the technical bottleneck of artificial breeding of long-thread fish Mansonia in China, obtains artificial seedlings to continue the reproduction of its population, and thus effectively maintains the ecological balance of natural waters and protects this rare and endangered aquatic germplasm resource. DETAILED DESCRIPTION

[0021] In order to make the technical solution and advantages of the present application clearer, the technical solution is clearly and completely described below in conjunction with embodiments.

[0022] Example 1

[0023] The artificial breeding of long-thread fish can be achieved by adopting the following breeding steps.

[0024] Step 1: Cultivation and ripening: In a pond with a water temperature of more than 20°C and a water depth of more than 2.5 meters, adult individuals of long-threaded fish over 6 years old are subjected to intensive cultivation. Cultivation and ripening also determine the date of female fish ripening injection by accumulating the daily average water temperature. Starting from January 1 of each year, the date when the accumulated daily average water temperature reaches 3700 degrees Celsius can be determined as the date of female fish ripening for that year. LRH-A3 is injected into the body cavity of female fish at a dosage of 0.5 micrograms / kg of fish body weight. The amount of liquid injected per female fish is 1.0-1.5 ml. The injection of LRH-A3 into the body cavity of the female fish is performed by injection at the base of the pectoral fin. Immediately after the injection, gently rub the injection point for 1-2 seconds to prevent the liquid from leaking out of the body. Feed forktail fish feed with a protein content of 35-38% twice a day at 5% of the fish body weight, mix in a complex multivitamin rich in vitamin E two days a week, and use a water pump or submersible aerator to create an internal circulation in the pond water to stimulate the development of the gonads of the broodstock.

[0025] Step 2: Selection of fish to be born: One month after the ripening date, squeeze the milky white semen that flows out of the cloaca of the long-threaded fish by hand and disperse it into the water. Use electron microscopy equipment to measure the sperm motility in the semen diluted 100 times, that is, select more than 5 sperm passing through the center of the same visual field in 1 minute as the standard to select male fish to be born, so as to ensure the effective sperm production and fertilization rate of male fish; when selecting female fish, select female fish with soft and swollen abdomen and visible ovarian groove on the back abdomen, and select broodstock whose ovaries have most of the eggs reaching mature egg diameter as female fish to be born. The selection is assisted by a handheld digital ultrasonic detector after anesthesia. The ovaries are explored by a digital ultrasonic detector, and female fish with more than 80% of the eggs with an egg diameter of more than 1.8 mm are selected to induce labor, so as to ensure the effective egg production and fertilization rate of female fish; MS-222 food-grade anesthetic is used for anesthesia. It is diluted with water at a dosage of 250 grams / cubic meter to soak and anesthetize the female and male fish to be born to prevent damage caused by violent swinging of the fish body.

[0026] Step 3: Injection for inducing labor: For female fish to be born, LRH-A2, DOM, and HCG are mixed with the dosage of scaleless fish inducing labor instructions to prepare a liquid medicine, which is injected into the fish body cavity twice. The dosage of the first injection is 1 / 3 of the total mixed dosage. After an interval of 10-12 hours, the remaining 2 / 3 of the dosage is injected for the second time. The injection volume of each female fish is 1.5-2 ml; the injection dosage of male fish to be born is 1 / 3-1 / 2 of that of the female fish to be born, which is synchronized with the second injection time of the female fish and completed at one time. The injection volume of each male fish is 1.0-1.5 ml; during injection, the needle is pointed toward the head of the fish, at a 45-degree angle to the axis of the fish body, and the needle is inserted from the base of the pectoral fin to a depth of 1 cm to push the liquid medicine to ensure that the liquid medicine enters the fish body cavity accurately and in sufficient quantity to exert the expected effect. The method of injecting the ripening and inducing labor liquid into the fish body cavity ensures that the drug is effectively absorbed by the fish body and fully developed. To exert the drug effect; the injected broodstock to be born are placed in a pool with a depth of 1.2 meters and an area of ​​100 square meters in a ratio of 1:1 between males and females, and a water pump is used to form an internal circulation of the pool water, maintaining the water temperature at 25 degrees Celsius, the water flow rate at 0.05 meters per second, and the dissolved oxygen in the water body above the standard of 5 mg / liter; after the effective period, the female and male fish to be born are caught in a ratio of 1:1 between males and females, and the water dripping on the surface of the fish is wiped dry with a dry towel, and the fish eggs and sperm are quickly squeezed into a large dry container. While squeezing the sperm and eggs, they are stirred with a goose main wing feather bundle. The goose main wing feather bundle is a bundle of 5-8 goose main wing feathers gathered and bundled together, with the feather shafts and barbs radiating outward. The goose main wing feather bundle is used to quickly stick the fertilized eggs to control the egg density, so that the eggs attached to the hatching mesh are 2 mm apart and not sticky, ensuring that the effects of water mold and oxygen consumption are effectively reduced. After squeezing out the sperm and eggs, add an appropriate amount of water and stir for fertilization for 10-15 seconds, then use a semi-submersible incubator to lay the eggs.

[0027] Step 4: Egg hatching: Place a semi-submersible hatching device in the water body of the pool for hatching. Specifically, the fertilized eggs are placed on a mesh of 40×60 cm through the semi-submersible hatching device, and hung at a water depth of 1 meter and an area of ​​15 square meters. The number of meshes is controlled within 40, the hatching water temperature is controlled at 23-28 degrees Celsius, the dissolved oxygen is maintained at more than 5 mg / L, the pH value is 7, the amount of new water for hatching is maintained at more than 0.5 cubic meters / hour, and the amount of water change is appropriately increased when the fry emerge from the membrane, and the drain outlet of the hatching pool is wrapped with 80-mesh polyethylene mesh; after all the fry emerge from the membrane, the hatching mesh is promptly removed to prevent the egg membrane on the mesh from decomposing and polluting the water quality.

[0028] Step 5: Fry cultivation: The fry will swim open within 36-48 hours after hatching, and then be fed with rotifers in the hatching pond or cultivated in the pond.

[0029] The rotifers are fed regularly in the pool every morning and afternoon, and the feeding amount is adjusted in time according to the survival of the rotifers in the water body half an hour after feeding. When the fry reaches 1.5 cm, powder feed with 42% protein kneaded into a ball is gradually added to stop feeding the rotifers, until the particle size of the feed is determined according to the fish caliber in the fingerling stage. A 200-mesh polyethylene scoop is used to carry water to feed the fry and rotifers, and at the same time, combined with the microphotographic sampling observation method, the number of fry per cubic water body in the nursery pool is controlled to be less than 10,000, and the number of live bait individuals fed is more than 10 times the number of fry, ensuring that the early cannibalism rate of the fry is effectively reduced.

[0030] The pond cultivation is to use algae seeds and fertilizer paste to cultivate good water quality 3-5 days in advance, and choose a period of sunny weather and water temperature of about 26°C to put the fry into the pond; after the fry are put into the pond, fertilizer paste and microecological preparations are regularly added to regulate the plankton in the pond water body, and when the fry reach 1.5 cm, start feeding powder feed with 42% protein, and gradually adjust the feeding of feed with appropriate particle size according to the caliber of the fish throughout the entire fish seed cultivation stage.

[0031] Incomplete statistics of breeding trials conducted at the test site are as follows:

[0032] Experimental group: the breeding technique of Example 1.

[0033] Control group 1 (CK1): Broodstock were placed in a pond at a ratio of 1:1 between male and female for natural breeding. The environment in the pond was the same as that in Example 1.

[0034] Control group 2 (CK2): the broodstock were not cultured and ripened, and were selected for spawning after two or more manual appearance inspections. The injection of spawning and the hatching conditions of the eggs were the same as those in Example 1.

[0035] Control group 3 (CK3): injection induced spawning was performed by injecting the female fish to be calved with the dosage of LRH-A2 for scaleless fish induced spawning; the other conditions were the same as those in Example 1.

[0036] Control group 4 (CK4): injection induced spawning was performed by injecting the DOM scaleless fish induced spawning dosage into the expectant female fish; the other conditions were the same as those in Example 1.

[0037] Control group 5 (CK5): injection induced spawning was performed by injecting the expectant female fish with HCG in the dosage indicated for induced spawning of scaleless fish; the other conditions were the same as those in Example 1.

[0038] Control group 6 (CK6): injection induced spawning was prepared by mixing LRH-A2 and DOM in the dosage of scaleless fish induced spawning for female fish to prepare a liquid for injection; the other conditions were the same as those in Example 1.

[0039] Control group 7 (CK7): injection induced labor was prepared by mixing LRH-A2 and HCG in the dosage of scaleless fish induced labor for female fish to prepare a liquid for injection; the other conditions were the same as those in Example 1.

[0040] Control group 8 (CK8): injection induced labor was prepared by mixing LRH-A2, DOM and HCG in the dosage of scaleless fish induced labor for female fish and injecting the mixture into the body cavity of the fish once; the other conditions were the same as those in Example 1.

[0041]

[0042] From the above record table, we can know that the cultivation and ripening, spawning selection and injection induction techniques are the key to the artificial breeding of long-thread fish.

[0043] Application Examples

[0044] The applicant has successfully applied this technology in Wuming District, Nanning City, Guangxi from 2017 to 2022 to achieve the expected breeding results. It is also the only report in China on artificial breeding of long-thread fish and obtained an aquatic wild animal breeding license; among them, about 100,000 long-thread fish seedlings were obtained in 2022, which is the best breeding result obtained after years of research and technical improvement.

[0045] In the pond with a depth of 3 meters and an area of ​​1,000 square meters in Wuming District, Nanning City, Guangxi, 100 adult individuals of 6-year-old long-finned fish (male and female fish are raised together) are stocked. Since the beginning of the year, 5% of the fish weight has been fed with forktail fish feed with a protein content of 35-38% twice a day, and a compound multivitamin rich in vitamin E is mixed in two days a week. The water temperature of the cultivation pond for breeding long-finned fish broodstock is ensured to be above 20℃ by building a transparent plastic film wintering shed and injecting deep well water. The wintering shed will not be removed until after the Qingming Festival in the lunar calendar to reduce the impact of the pond water temperature on the drastic cooling climate. Since the beginning of the year, the pond water temperature has been measured every morning, noon and evening. When the daily average water temperature (the daily average water temperature is accumulated) reaches 3700℃, the broodstock of long-striped fish are caught, and the drug solution is prepared by adding 0.45% physiological saline to the dosage of LRH-A3 at a dosage of 0.5 micrograms / kg of fish weight. According to the weight of the fish, 1.0-1.5 ml of the drug solution is injected into the body cavity of each female fish by injection at the base of the pectoral fin. Immediately after the injection, the injection point is gently rubbed with fingers. Afterwards, a water pump or submersible aerator is used to form an internal circulation in the pond water to stimulate the gonadal development of the broodstock.

[0046] After LRH-A3 is ripened for one month, MS-222 food-grade anesthetic is used. It is diluted with water at a dosage of 250 g / cubic meter and soaked for anesthesia to examine the female and male fish to be born. The milky white semen that flows out of the cloaca of the long-threaded fish awn and disperses as soon as it enters the water is squeezed by hand, and the number of sperm that passes through the same central point of the visual field within 1 minute in the 100-fold diluted semen is measured by electron microscopy equipment. The male fish to be born are selected as the standard; for female fish with soft and swollen abdomen and obvious ovarian groove visible on the back abdomen, a handheld digital ultrasonic detector is used to assist in the exploration, and the broodstock with most of the eggs in the ovaries and eggs with a diameter of more than 1.8 mm accounting for more than 80% are selected as the female fish to be born.

[0047] According to the total weight of the female fish to be born, the dosage of LRH-A2, DOM, and HCG for scaleless fish induced labor is mixed with 0.45% saline to prepare a liquid medicine, which is injected into the fish body cavity twice. The first injection dosage is 1 / 3 of the total mixed dosage, and the remaining 2 / 3 dosage is injected for the second time after an interval of 10-12 hours. According to the weight of the fish, the injection volume of the liquid medicine for each female fish is 1.5-2 ml. The injection dosage of the male fish to be born is 1 / 3-1 / 2 of the female fish to be born, which is synchronized with the second injection time of the female fish, and the injection is completed at one time. According to the weight of the fish, the injection volume of the liquid medicine for each male fish is 1.0-1.5 ml. The parent fish to be born injected with drugs are placed in a pool with a water depth of 1.2 meters and an area of ​​100 square meters in a ratio of 1:1 between male and female, and a water pump is used to form an internal circulation of the pool water, maintaining the water temperature at 25 degrees Celsius, the water flow rate at 0.05 meters / second, and the dissolved oxygen in the water body above the standard of 5 mg / L. After the 12-hour effective period, catch the female and male fish in a 1:1 ratio. After wiping off the water on the fish's body with a dry towel, quickly squeeze the eggs and eggs into a large dry container. Stir with the goose's main wing feathers while squeezing the eggs. After squeezing out the eggs, add a small amount of water and stir for fertilization for 10-15 seconds. Then use a semi-submersible incubator to lay the eggs.

[0048] The fertilized fish eggs are placed on a hatching mesh with a specification of 40×60 cm by a semi-submerged hatching device and a fast sticking method of goose main wing feather bundles. The appropriate egg density is that the eggs attached to the mesh are 2 mm apart and not sticky. The mesh after laying eggs is hung in a pool with a water depth of 1 meter and an area of ​​15 square meters for hatching. The number of meshes is controlled within 40 pieces, the hatching water temperature is controlled at 23-28 degrees Celsius, the dissolved oxygen is maintained at more than 5 mg / L, and the pH value is about 7. The amount of new water for hatching is maintained at more than 0.5 cubic meters / hour. When the fry emerges from the membrane, the amount of water change is appropriately increased, and the drain of the hatching pool is wrapped with 80 mesh polyethylene mesh. After all the fry emerge from the membrane, the hatching mesh is removed in time to prevent the egg membrane on the mesh from decomposing and polluting the water quality.

[0049] The fry will swim and open within 36-48 hours after hatching. Then, they can be fed with rotifers in the hatching pool or cultivated in the pond. When cultivating fry in the pond, use a 200-mesh polyethylene scoop to carry water to throw the fry and take water samples for microscopic observation to ensure that the density of fry in the pond is controlled below 10,000 fry per cubic meter of water. Feed rotifers regularly in the morning and afternoon every day, and adjust the feeding amount in time according to the survival of rotifers in the water body observed by microscopic photography half an hour after feeding. It is advisable that the number of rotifers fed is more than 10 times the number of fry. When the fry reaches 1.5 cm, gradually add powdered feed with 42% protein and stop feeding rotifers until the fingerling stage, the particle size of the feed is determined according to the fish caliber. When cultivating fry in the pond, use algae seeds and fertilizer paste to cultivate good water quality 3-5 days in advance, and choose a sunny day with a water temperature of about 26℃ to release the fry into the pond. After the fry are put into the pond, fertilizer paste and microecological preparations are regularly added to regulate the plankton in the pond water. When the fry reach 1.5 cm, powder feed with 42% protein is started to be fed. The feed particle size is gradually adjusted according to the caliber of the fish throughout the entire fish breeding stage.

[0050] The above description is not a limitation of the present application, and the present application is not limited to the above examples. Any changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present application should fall within the scope of protection of the present application.

Claims

1. A method for artificially breeding filamentous fish, characterized in that: The breeding steps include: Step 1: Cultivation and ripening: In a pond with a water temperature of more than 20°C and a water depth of more than 2.5 meters, adult individuals of long-threaded fish over 6 years old are subjected to intensive cultivation. The cultivation and ripening also determines the injection date of female fish ripening by accumulating the daily average water temperature, that is, the method of accumulating the daily average water temperature to reach 3700 degrees Celsius from January 1st of each year determines the ripening date of female fish in that year, and injects LRH-A3 into the body cavity of female fish according to the dosage of 0.5 micrograms / kg of fish body weight and 0.45% physiological saline according to the instructions for use. The injection volume of the liquid for each female fish is 1.0-1.5 ml; the injection of LRH-A3 into the body cavity of the female fish is injected at the base of the pectoral fin, and the injection point is gently rubbed for 1-2 seconds immediately after the injection; Step 2: Selection of fish to be laid: One month after the ripening date, select the broodstock whose cloaca leaks milky white semen as soon as it enters the water as the male fish to be laid, and select the broodstock whose ovaries have most of the eggs reaching the mature egg diameter as the female fish to be laid; the selection is to use a handheld digital ultrasonic detector to assist in the exploration and selection after anesthesia, and use the digital ultrasonic detector to explore the ovaries, and select female fish with more than 80% of the eggs with a diameter of more than 1.8 mm to induce spawning, so as to ensure the effective egg-laying amount and fertilization rate of the female fish; anesthesia uses MS-222 food-grade anesthetics, and the male and female fish to be laid are soaked in water at a dosage of 250 grams / cubic meter for anesthesia inspection; Step 3: Injection for induced labor: The female fish to be born is mixed with LRH-A2, DOM, and HCG according to the instructions for induced labor for scaleless fish to make a liquid medicine, which is injected into the fish body cavity twice. The first injection is 1 / 3 of the total mixed medicine. After an interval of 10-12 hours, the remaining 2 / 3 of the medicine is injected for the second time. The injection volume of each female fish is 1.5-2 ml; the injection volume of the male fish to be born is 1 / 3-1 / 2 of the female fish to be born, which is synchronized with the second injection time of the female fish. The injection is completed at one time. The injection volume of each male fish is 1.0-1.5 ml. milliliters; the parent fish injected with drugs are put into a pond together, and a water pump is used to form an internal circulation of the pond water, maintaining the water temperature at 25 degrees Celsius, the water flow rate at 0.05 meters per second, and the dissolved oxygen in the water body above the standard of 5 mg / liter; after the effective period, the female fish and male fish are caught in a ratio of 1:1, and the fish body surface is wiped dry with a dry towel, and the eggs and sperm are quickly squeezed into a large dry container, and the eggs are squeezed while stirring with the main wing feathers of the goose. After squeezing the eggs, add an appropriate amount of water and stir for fertilization for 10-15 seconds, and then use a semi-submersible incubator to lay eggs; Step 4: Fish egg hatching: Place the semi-submersible hatching device in the water body of the pool for hatching. The hatching water temperature is controlled at 23-28 degrees Celsius, the dissolved oxygen is maintained at more than 5 mg / L, and the pH value is 6.8-7.

2. The amount of new water for hatching is maintained at more than 0.5 cubic meters / hour. When the fry emerge from the membrane, the amount of water change is appropriately increased, and the drain outlet of the hatching pool is wrapped with 80-mesh polyethylene mesh; Step 5: Fry cultivation: The fry will swim open within 36-48 hours after hatching, and then be fed with rotifers in the hatching pond or cultivated in the pond.

2. The artificial breeding method of filamentous fish awn according to claim 1, characterized in that: In step one, the fish are cultivated and ripened by feeding forktail fish feed with a protein content of 35-38% twice a day at 5% of the fish body weight. A multivitamin rich in vitamin E is mixed in two days a week, and a water pump or submersible aerator is used to form an internal circulation in the pond water to stimulate the development of the gonads of the broodstock.

3. The artificial breeding method of filamentous fish awn according to claim 1, characterized in that: The goose main wing feather bundle is obtained by gathering and bundling the feather roots of 5 to 8 main wing feathers, and the feather shafts and feather branches are radially distributed outwards.

4. The artificial breeding method of filamentous fish as claimed in claim 1, characterized in that: The rotifers are fed in the pool at regular intervals in the morning and afternoon every day, and the feeding amount is adjusted in time according to the survival situation of the rotifers in the water body half an hour after feeding. When the fry reaches 1.5 cm, powder feed kneaded into balls and with a protein content of 42% is gradually added and the rotifer feeding is stopped, until the particle size of the feed is determined according to the fish caliber in the fingerling stage.

5. The artificial breeding method of filamentous fish as claimed in claim 1, characterized in that: The pond cultivation is to use algae seeds and fertilizer paste to cultivate good water quality 3-5 days in advance, and choose a period of sunny weather and water temperature of about 26°C to put the fry into the pond; after the fry are put into the pond, fertilizer paste and microecological preparations are regularly added to regulate the plankton in the pond water body, and when the fry reach 1.5 cm, start feeding powder feed with a protein content of 42%, and gradually adjust the feeding of feed with appropriate particle size according to the caliber of the fish throughout the entire fish seed cultivation stage.

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