Artificial propagation method of epinephelus coioides

Abstract

The invention provides an artificial propagation method for epinephelus coioides, and relates to the technical field of epinephelus coioides propagation. The method comprises the following steps: S1, parent selection; s2, parent breeding and nutrient enrichment; s3, parent spawning induction; s4, artificial insemination; according to the steps, the breeding conditions of the epinephelus coioides are improved, egg laying is promoted through nutrient enrichment, and development is properly induced, so that the fry breeding survival rate of the epinephelus coioides in the artificial breeding process is effectively increased, and large-scale breeding of the epinephelus coioides is achieved; and a large batch of high-quality epinephelus coioides fries can be stably obtained.

Description

Technical Field

[0001] The invention relates to the technical field of grouper breeding, in particular to an artificial breeding method of blue-bodied big-spotted grouper. Background Art

[0002] Grouper is a kind of carnivorous reef-dwelling fish that lives in tropical and subtropical waters. It belongs to the family Epinephelus of the order Perciformes. The family Epinephelus includes 16 genera and 165 species with rich phenotypes. They are famous for their delicious meat and rich nutrition. They are known as "chicken of the sea" and are an important edible fish in my country's southern coastal areas. Guangdong Province, Hainan Province, and Fujian Province have always been important areas for the supply of grouper seedlings and commercial fish farming. According to my country's Fisheries Statistical Yearbook, my country's annual production of grouper has reached 241,000 tons, ranking fourth in my country's marine fish production. Grouper is an important farmed economic fish in my country.

[0003] Epinephelus tukula, also known as the golden grouper, is the second largest species in the grouper family, second only to the saddle grouper. It can reach a maximum weight of 100 kg and a body length of more than 2 meters. Because of its growth advantage and low temperature resistance, the blue-bodied grouper is an important paternal parent in grouper hybrid breeding. The Golden Tiger hybrid grouper (brown-spotted grouper♀×blue-bodied grouper♂) and the Golden Rat hybrid grouper (humpback perch♀×blue-bodied grouper♂) are both based on the blue-bodied grouper as the paternal parent. The Golden Tiger hybrid grouper has become an important farmed grouper in my country. Although the blue-bodied grouper plays an important role in grouper breeding, the large-scale breeding of the blue-bodied grouper has not yet been solved, and it is impossible to obtain high-quality seedlings on a large scale in a stable manner.

[0004] In view of this, it is necessary to design an improved artificial breeding method of blue body big spot grouper to solve the above problems. Summary of the invention

[0005] The invention aims to provide an artificial breeding method for blue-bodied giant grouper.

[0006] To achieve the above-mentioned object of the invention, the present invention provides an artificial breeding method for blue-bodied big-spotted grouper, comprising the following steps:

[0007] S1. Parent selection:

[0008] Use healthy blue-bodied grouper over 4 years old and weighing more than 10 kg as reserve parents;

[0009] S2. Breeding and nutritional fortification of parents:

[0010] Choose the breeding environment: in a volume of not less than 30m 3, the reserve parent should be cultured in a pond with a water depth greater than 1.5m. The water temperature of the pond should be 28-31℃, the salinity should be 26-33‰, the pH should be 7.8-8.5, the ammonia nitrogen content should be less than 0.1mg / L, and the culture density should not exceed 10 kg / m 3 The water change frequency is 6 times / day. During the culture process, the light intensity is 3000-4000 lux during the light treatment and less than 30 lux during the dark treatment.

[0011] Nutritional fortification: In the first six months of spawning / sperm production, the reserve parent needs to be continuously fed with feed A and feed B for nutritional fortification. Feed A is fed once a day, and feed B is fed once every three days. Feed A is freshly-frozen bonito coated with a nutritional enhancer. Each time feed A is fed, the feeding amount of freshly-frozen bonito should be 2-4% of the total weight of the reserve parent. Feed B is freshly-shucked oysters and freshly-frozen squid coated with a nutritional enhancer. The feeding ratio of freshly-shucked oysters and freshly-frozen squid is 4:6, and the feeding amount of freshly-shucked oysters is 2-4% of the total weight of the reserve parent.

[0012] S3. Parental induction of labor:

[0013] After nutritional fortification, female parents with obviously enlarged abdomens and male parents with obvious masculine traits were selected for induced spawning;

[0014] S4. Artificial insemination:

[0015] On the day of fertilization, collect the eggs of the female parent and the semen of the male parent respectively; add the semen to the clean seawater, mix well, add the eggs, mix well, let stand for 5 minutes, and wash the fertilized eggs with seawater;

[0016] S5. Hatching of fertilized eggs: Use outdoor pond breeding method or indoor cement pool breeding method for breeding. After 35 days of breeding, fully developed fry are obtained. During the breeding process, the water temperature is 26-35℃, the salinity is 25-33‰, and the ammonia nitrogen is lower than 0.1mg / L.

[0017] Preferably, in step S2, the preparation method of feed A is as follows: after thawing 10 kg of chilled food and draining the water, mix and stir with 200 g of a nutritional enhancer so that the nutritional enhancer adheres to the chilled food, the nutritional enhancer is obtained by mixing the enhancer and food-grade Tween-80 in a mass ratio of 1:1, and the enhancer is composed of: 5 parts of Schizochytrium powder, 2 parts of maca powder, 1 part of epimedium, 1 part of folic acid, 2 parts of vitamin C, 1 part of vitamin E, 0.5 parts of vitamin A, 0.2 parts of vitamin B5, 0.2 parts of vitamin D, and 0.2 parts of zinc chloride.

[0018] Preferably, in step S3, the specific steps of inducing labor are as follows: injecting 150-200 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogues into the female parent 72 hours before spawning, and injecting 150-200 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogues again 48 hours before spawning; injecting oxytocin 48 hours before spermatogenesis into the male parent, the oxytocin is 100-150 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogues.

[0019] Preferably, in step S1, each breeding pond further comprises 8-10 mature brown-spotted groupers weighing 6-10 kg, which are used to promote the maturation of the reserve parents.

[0020] Preferably, in step S3, after the male parent and the female parent are injected with hormones, they are exposed to light for 12 hours and treated in darkness for 12 hours; the light intensity during illumination is 1500-4000 lux, and the light intensity during dark treatment is less than 30 lux.

[0021] Preferably, in step S4, the semen collection method is as follows: at 14:00-17:00 on the day of fertilization, use 20ppm eugenol to anesthetize the male parent, and after losing balance, place it on the production table, and slowly push down from about 15cm above the cloaca and 5cm from the side of the center line of the fish abdomen. When white viscous semen flows out of the cloaca, use a clean dry towel to wipe the cloaca clean, use a sterile 10ml centrifuge tube to collect the white viscous semen, check the sperm under a microscope with a magnification of 40 times, and retain sperm with a sperm motility greater than 60%.

[0022] Preferably, in step S4, the egg collection method is as follows: between 19:00 and 23:00 on the day of fertilization, the female parent is placed on a production table and her abdomen is massaged until the eggs flow out along a conical bag into a collection bucket. The eggs need to be artificially inseminated within 10 minutes after collection.

[0023] Preferably, in step S1, the total number of reserve parents in each breeding pond during the breeding process is not less than 10.

[0024] Preferably, the outdoor pond seedling method is carried out as follows: a floating hatching bag is built in the pond, and the fertilized eggs are placed in the hatching bag for hatching. The amount of eggs corresponding to each cubic meter of water in the hatching bag is not higher than 0.1 kg. When the fry begin to ingest exogenous substances, the fry are placed in the pond for cultivation, and 1 billion rotifers are placed in the pond at the same time. Ten days after hatching, the nauplii of brine shrimp are fed until they are full; 21 days after hatching, copepods are fed until they are full; 35 days after hatching, fully metamorphosed and fully developed fry are obtained; the water temperature of the water body in the hatching bag is 26-35°C, the salinity is 25-33‰, the ammonia nitrogen is lower than 0.1 mg / L, and the weight of the fertilized eggs in each pond is 0.4-1.2 kg.

[0025] Preferably, the indoor cement pool seedling method is carried out as follows: fertilized eggs are placed in a cement pool for hatching, and when the fry begin to ingest exogenous substances, 1 billion rotifers are placed in the cement pool. Ten days after hatching, nauplii of brine shrimp are fed until they are full; 21 days after hatching, copepods are fed until they are full; 35 days after hatching, fully metamorphosed and fully developed fry are obtained; the water temperature of the water in the hatching bag is 26-35°C, the salinity is 25-33‰, the ammonia nitrogen is less than 0.1 mg / L, and the weight of the fertilized eggs in each pond is 0.1-0.3 kg.

[0026] The beneficial effects of the present invention are:

[0027] The artificial breeding method of the blue-bodied big spot grouper provided by the present invention effectively improves the survival rate of the blue-bodied big spot grouper seedlings during the artificial breeding process by improving the breeding conditions of the blue-bodied big spot grouper, promoting spawning through nutritional enhancement, and appropriately inducing development, thereby realizing the large-scale breeding of the blue-bodied big spot grouper and stably obtaining a large number of high-quality blue-bodied big spot grouper seedlings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention provides a flow chart of the artificial propagation method of blue-bodied giant grouper. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0031] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0032] See also Figure 1 As shown, the present invention provides an artificial breeding method for blue-bodied big-spotted grouper, comprising the following steps:

[0033] S1. Parent selection:

[0034] When the blue-bodied big-spotted grouper reaches more than 4 years old, the selection of reserve parents begins, and blue-bodied big-spotted grouper with no deformity, no injury, and weighing more than 10 kg are selected as reserve parents; if fish bred in the same period are selected as reserve parents, fish in the top 5% by weight must be selected first, and then the internal structure of the fish must be detected using an ultrasound machine. Fish with well-developed testes are selected as male reserve parents, and fish with well-developed ovaries and uniform ovarian image texture are selected as female reserve parents;

[0035] S2. Breeding and nutritional fortification of parents:

[0036] Choose the breeding environment: in a volume of not less than 30m 3 , the reserve parent should be cultured in a pond with a water depth greater than 1.5m. The water temperature of the pond should be 28-31℃, the salinity should be 26-33‰, the pH should be 7.8-8.5, the ammonia nitrogen content should be less than 0.1mg / L, and the culture density should not exceed 10 kg / m 3 , the water change frequency is 6 times / day, the light exposure is 16 hours per day and the dark treatment is 8 hours per day during the breeding process, the light intensity during the light exposure is 3000-4000 lux, and the light intensity during the dark treatment must be lower than 30 lux. During the breeding process, the total number of reserve parents in each breeding pond is not less than 10 to maintain a certain group size; in particular, in order to promote the maturity of the parents, 8-10 mature brown spot groupers weighing 6-10 kg are placed in each breeding pond;

[0037] Nutritional fortification: The backup parent needs to be continuously fed with feed A and feed B for nutritional fortification in the first six months of spawning / sperm production. Feed A is fed once a day, and feed B is fed once every three days. Feeding should be done slowly to ensure that the feed is eaten by the fish. Feed A is fresh iced bonito coated with a nutritional enhancer. Each time feed A is fed, the amount of fresh iced bonito should be 2-4% of the total weight of the backup parent. The preparation method is as follows: 10 kg of fresh iced bonito is thawed and drained, and then mixed with 200 g of nutritional enhancer to make the nutritional enhancer adhere to the fresh iced bonito. The nutritional enhancer is a mixture of enhancer and food-grade Tween-80 according to the quality control method. The feed B is chilled shucked oysters and chilled squid coated with the nutritional enhancer, the feeding ratio of the chilled shucked oysters and the chilled squid is 4:6, the feeding amount of the chilled shucked oysters is 2-4% of the total weight of the reserve parent, and the process of coating the nutritional enhancer on the surface of the chilled shucked oysters and the chilled squid is the same as the preparation method of feed A;

[0038] S3. Parental induction of labor:

[0039] After nutritional fortification, female parents with obviously swollen abdomens and male parents with obvious male characteristics are selected for induced labor. 150-200 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogs are injected into the female parents 72 hours before spawning, and 150-200 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogs are injected again 48 hours before spawning; oxytocin is injected into the male parents 48 hours before spermatogenesis, and the oxytocin is 100-150 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogs. After the injection of oxytocin, the female parents and the male parents are exposed to light for 12 hours and dark for 12 hours, wherein the light intensity during light exposure is 1500-4000 lux, and the light intensity during dark treatment needs to be less than 30 lux;

[0040] S4. Artificial insemination:

[0041] On the day of fertilization, sperm was obtained from 14:00 to 17:00. The method was as follows: the male parent was anesthetized with 20ppm eugenol. After losing balance, it was placed on the production table. From about 15cm above the cloaca, 5cm from the side of the center line of the fish's abdomen, it was slowly pushed down. When white viscous semen flowed out of the cloaca, it was wiped clean with a clean dry towel. A sterile 10ml centrifuge tube was used to collect the white viscous semen. After squeezing one side, the fish was turned over and the squeezing and pushing operation was repeated again. The sperm was checked under a microscope with a magnification of 40 times. The sperm could be used if the sperm motility was greater than 60%. The usable sperm was stored at 4℃ for later use.

[0042] 19:00-23:00 to obtain eggs, the method is as follows: place the female parent on the production table, massage its abdomen until the eggs flow out, and the eggs flow into the collection bucket along the conical bag. The eggs need to be artificially inseminated within 10 minutes after collection. The artificial insemination method is as follows: add 5L of clean seawater to a 15L bucket, then add semen, mix well, and quickly put the eggs into the bucket to mix the eggs and sperm evenly. After standing for 5 minutes, use an 80-mesh filter to filter out the seawater, and use clean seawater to wash 2-4 times to obtain the fertilized eggs of blue-bodied big spotted grouper;

[0043] The fertilized eggs are placed in 500-1000L aerated seawater with a water temperature of 26-31°C and a salinity of 25-33‰. The dead eggs are removed through the bottom layer at 3h, 6h, 10h and 16h after fertilization to prevent water corruption.

[0044] S5. Hatching of fertilized eggs:

[0045] The outdoor pond method or indoor cement pool method is used for raising seedlings. The outdoor pond method is carried out as follows: a floating hatching bag is built in the pond, and the fertilized eggs are placed in the hatching bag for hatching. The amount of eggs corresponding to each cubic meter of water in the hatching bag is not more than 0.1 kg. When the fry begin to ingest exogenous substances, the fry are placed in the pond for cultivation. At the same time, 1 billion rotifers are placed in the pond. Ten days after hatching, the nauplii of brine shrimp are fed until they are full (i.e. the fry no longer eat); 21 days after hatching, copepods are fed until they are full; 35 days after hatching, fully metamorphosed and fully developed fry are obtained; the water temperature in the hatching bag is 26-35℃, the salinity is 25-33‰, the ammonia nitrogen is less than 0.1mg / L, and the weight of the fertilized eggs in each pond is 0.4-1.2 kg;

[0046] The indoor cement pool seedling method is carried out as follows: the fertilized eggs are placed in the cement pool for hatching. When the fry begin to ingest exogenous substances, 1 billion rotifers are placed in the cement pool. Ten days after hatching, the nauplii of brine shrimp are fed until they are full; 21 days after hatching, copepods are fed until they are full; 35 days after hatching, fully metamorphosed and developed fry are obtained; the water temperature in the hatching bag is 26-35℃, the salinity is 25-33‰, the ammonia nitrogen is less than 0.1mg / L, and the weight of the fertilized eggs in each pond is 0.1-0.3 kg.

[0047] The artificial propagation method of blue-bodied giant grouper of the present invention will be further described below in conjunction with specific embodiments:

[0048] Example 1

[0049] This embodiment provides an artificial breeding method for blue-bodied big-spotted grouper, comprising the following steps:

[0050] S1. Use healthy blue-bodied grouper over 4 years old and weighing 10.6-17.2 kg as reserve parents;

[0051] S2. Select the breeding environment: in a volume of 40m 3 The parent was cultured in a 1.5m deep pond with a water temperature of 29°C, a salinity of 31‰, a pH of 8.1, an ammonia nitrogen content of 0mg / L, and a culture density of 3.6 kg / m 3 , the water change frequency is 6 times / day, the light intensity is 3000 lux during the light treatment and 10 lux during the dark treatment during the breeding process, and the number of female parents in each breeding pond is 16 to maintain a certain group size; in particular, in order to promote the maturity of the parents, 8 mature brown spot groupers are placed in each breeding pond;

[0052] Nutritional fortification: Blue-bodied big-spotted grouper needs to be continuously fed with feed A and feed B for nutritional fortification six months before spawning. Feed A is fed once a day, and feed B is fed once every three days. Feeding should be done slowly to ensure that the feed is eaten by the fish. Feed A is fresh ice bonito coated with a nutritional enhancer. Each time feed A is fed, the feeding amount of fresh ice bonito should be 3% of the parent weight. The preparation method is as follows: 10 kg of fresh ice is thawed and drained, and then mixed with 200 g of nutritional enhancer to make the nutritional enhancer adhere to the fresh ice. The nutritional enhancer is a mixture of enhancer and food-grade Tween-80 in a mass ratio of 1:1. , the composition of the enhancer is: 5 parts of Schizochytrium powder, 2 parts of Maca powder, 1 part of Epimedium, 1 part of folic acid, 2 parts of vitamin C, 1 part of vitamin E, 0.5 parts of vitamin A, 0.2 parts of vitamin B5, 0.2 parts of vitamin D, and 0.2 parts of zinc chloride; Feed B is chilled shucked oysters and chilled squids coated with nutritional enhancers on the surface, the feeding ratio of chilled shucked oysters and chilled squids is 4:6, and they are enhanced and fed according to the above method, the feeding amount of shelled oysters is 3% of the total weight of the reserve parent, and the process of coating the nutritional enhancer on the surface of chilled shucked oysters and chilled squids is the same as the preparation method of feed A, which will not be repeated here;

[0053] S3. After nutritional fortification, select female parents with obviously swollen abdomen and male parents with obvious male traits for induced labor. Inject 150 IU / kg chorionic gonadotropin and 10 μg / kg luteinizing hormone releasing hormone analogues 72 hours before the female parents lay eggs, and inject 150 IU / kg chorionic gonadotropin and 10 μg / kg luteinizing hormone releasing hormone analogues 48 hours before laying eggs; inject oxytocin 48 hours before the male parents lay sperm, and the oxytocin is 150 IU / kg chorionic gonadotropin and 15 μg / kg luteinizing hormone releasing hormone analogues. After the injection of oxytocin, the female parents and the male parents are exposed to light for 12 hours at a light intensity of 3000 lux and dark for 12 hours at a light intensity of 15 lux.

[0054] S4. On the day of fertilization, sperm was obtained at 14:00. The method was as follows: the male parent was anesthetized with 20ppm eugenol. After losing balance, it was placed on the production table. From about 15cm above the cloaca and 5cm from the side of the center line of the fish's abdomen, it was slowly pushed down. When white viscous semen flowed out of the cloaca, it was wiped clean with a clean dry towel. The white viscous semen was collected with a sterile 10ml centrifuge tube. After squeezing one side, the fish was turned over and the squeezing and pushing operation was repeated again. The sperm was checked under a microscope with a magnification of 40 times. The sperm motility was 80%. The sperm was stored at 4℃ for later use.

[0055] At 22:00, the eggs were obtained as follows: the female parent was placed on the production table, and the abdomen was massaged until the eggs flowed out, and the eggs flowed into the collection bucket along the conical bag. The eggs needed to be artificially inseminated within 10 minutes. The artificial insemination method was as follows: 5L of clean seawater was added to a 15L bucket, and then semen was added, mixed, and the eggs were quickly placed in the bucket to mix the eggs and sperm evenly. After standing for 5 minutes, the seawater was filtered out with an 80-mesh filter, and cleaned with clean seawater 4 times to obtain 3.2 kg of fertilized eggs of blue-bodied big spotted grouper;

[0056] The fertilized eggs were placed in 500L aerated seawater with a water temperature of 29°C and a salinity of 31‰. Dead eggs were removed at 3h, 6h, 10h, and 16h after fertilization to prevent water corruption.

[0057] S5. The outdoor pond seedling raising method is used for seedling raising. The specific method is as follows: floating hatching bags are built in 4 ponds of 3 mu respectively, 0.8 kg of fertilized eggs are put into each pond, and the fertilized eggs are placed in the hatching bags for hatching. The amount of eggs corresponding to each cubic meter of water in the hatching bags is 0.067 kg. When the fry begin to emerge from the membrane, the inflation in the hatching bag is adjusted to a small amount and maintained at a slight inflation. When the fry begin to ingest exogenous substances, the fry are placed in the pond for cultivation, and 1 billion rotifers are placed in the pond at the same time. Ten days after hatching, the nauplii of brine shrimp are fed instead; 21 days after hatching, copepods are fed; 35 days after hatching, the metamorphosis is completed and the fully developed fry are obtained; the water temperature in the hatching bag is 29°C, the salinity is 31‰, and the ammonia nitrogen is 0 mg / L. Under the above breeding method, the hatching rate, the number of 3cm fry, the survival rate and the number of fry produced per kilogram of eggs were calculated; the hatching rate was calculated as the ratio of the number of hatched fish flowers to the number of fertilized eggs; the number of fry was the number of fry of about 3cm after the metamorphosis of grouper fry was completed; the survival rate was the ratio of the number of fry of about 3cm to the number of hatched fish flowers. The statistical results of fry production are shown in Table 1. The results show that 3.2 kg of fertilized eggs produced a total of 634,000 fry, the hatching rate of fertilized eggs was 71.1-81.2%, and the survival rate of fry reached 15.25-18.25%.

[0058] Table 1 Statistical results of seedling production of blue-bodied grouper in Example 1

[0059]

[0060] Example 2

[0061] This embodiment provides an artificial breeding method for blue-bodied big-spotted grouper, comprising the following steps:

[0062] S1. A healthy blue-bodied grouper over 5 years old and weighing more than 10 kg is used as the male parent; a healthy blue-bodied grouper over 4 years old and weighing more than the male parent is used as the female parent;

[0063] S2. Select the breeding environment: in a volume of 30m 3 The parent stock was cultured in a 1.5m deep pond with a water temperature of 30°C, a salinity of 31‰, a pH of 9.1, an ammonia nitrogen content of 0mg / L, and a culture density of no more than 5 kg / m 3 , the water change frequency is 6 times / day, the light intensity is 3000 lux during the light treatment and 10 lux during the dark treatment during the breeding process, and the number of female parents in each breeding pond is 13 to maintain a certain group size; in particular, in order to promote the maturity of the parents, 6 mature brown spot groupers are placed in each breeding pond;

[0064] Nutritional fortification: Blue-bodied big-spotted grouper needs to be continuously fed with feed A and feed B for nutritional fortification six months before spawning. Feed A is fed once a day, and feed B is fed once every three days. Feeding should be done slowly to ensure that the feed is eaten by the fish. Feed A is fresh ice bonito coated with a nutritional enhancer. Each time feed A is fed, the feeding amount of fresh ice bonito should be 3% of the parent weight. The preparation method is as follows: 10 kg of fresh ice is thawed and drained, and then mixed with 200 g of nutritional enhancer to make the nutritional enhancer adhere to the fresh ice. The nutritional enhancer is a mixture of enhancer and food-grade Tween-80 in a mass ratio of 1:1. , the composition of the enhancer is: 5 parts of Schizochytrium powder, 2 parts of Maca powder, 1 part of Epimedium, 1 part of folic acid, 2 parts of vitamin C, 1 part of vitamin E, 0.5 parts of vitamin A, 0.2 parts of vitamin B5, 0.2 parts of vitamin D, and 0.2 parts of zinc chloride; Feed B is chilled shucked oysters and chilled squids coated with nutritional enhancers on the surface, the feeding ratio of chilled shucked oysters and chilled squids is 4:6, and they are enhanced and fed according to the above method, the feeding amount of shelled oysters is 3% of the total weight of the reserve parent, and the process of coating the nutritional enhancer on the surface of chilled shucked oysters and chilled squids is the same as the preparation method of feed A, which will not be repeated here;

[0065] S3. After nutritional fortification, female parents with obviously swollen abdomens and male parents with obvious male traits were selected for induced labor. 150 IU / kg chorionic gonadotropin and 10 μg / kg luteinizing hormone-releasing hormone analogs were injected into the female parents 72 hours before spawning, and 150 IU / kg chorionic gonadotropin and 10 μg / kg luteinizing hormone-releasing hormone analogs were injected 48 hours before spawning; oxytocin was injected into the male parents 48 hours before spermatogenesis, and the oxytocin was 150 IU / kg chorionic gonadotropin and 15 μg / kg luteinizing hormone-releasing hormone analogs. After hormone injection, the female and male parents were illuminated for 12 hours under the condition of light intensity of 2600 lux, and darkened for 12 hours under the condition of light intensity of 25 lux;

[0066] S4. On the day of fertilization, sperm was obtained at 16:00. The method was as follows: the male parent was anesthetized with 20ppm eugenol. After losing balance, it was placed on the production table. From about 15cm above the cloaca and 5cm from the side of the center line of the fish's abdomen, it was slowly pushed down. When white viscous semen flowed out of the cloaca, it was wiped clean with a clean dry towel. The white viscous semen was collected with a sterile 10ml centrifuge tube. After squeezing one side, the fish was turned over and the squeezing and pushing operation was repeated again. The sperm was checked under a microscope with a magnification of 40 times. The sperm motility was 80%. The sperm was stored at 4℃ for later use.

[0067] At 22:00, the eggs were obtained as follows: the female parent was placed on the production table, and the abdomen was massaged until the eggs flowed out, and the eggs flowed into the collection bucket along the conical bag. The eggs needed to be artificially inseminated within 10 minutes. The artificial insemination method was as follows: 5L of clean seawater was added to a 15L bucket, and then semen was added, mixed, and the eggs were quickly placed in the bucket to mix the eggs and sperm evenly. After standing for 5 minutes, the seawater was filtered out with an 80-mesh filter, and cleaned with clean seawater 4 times to obtain 2 kg of fertilized eggs of blue-bodied big spotted grouper;

[0068] The fertilized eggs were placed in 500L aerated seawater with a water temperature of 30°C and a salinity of 31‰. Dead eggs were removed at 3h, 6h, 10h, and 16h after fertilization to prevent water corruption.

[0069] S5. Indoor cement pool seedling raising method is used for seedling raising. The specific method is as follows: fertilized eggs are placed in 10 25-cubic-meter cement pools for hatching, and 0.2 kg of fertilized eggs are placed in each cement pool. When the fry begin to ingest exogenous substances, 1 billion rotifers are placed in the cement pool. After 10 days of hatching, the nauplii of brine shrimp are fed instead; after 21 days of hatching, copepods are fed; after 35 days of hatching, the metamorphosis is completed and the fully developed fry is obtained; the water temperature of the water body in the hatching bag is 30℃, the salinity is 31‰, and the ammonia nitrogen is 0mg / L. Under the above breeding method, the hatching rate, the number of 3cm fry, the survival rate and the number of fry produced per kilogram of eggs are counted; the hatching rate is calculated as the ratio of the number of hatched fish flowers to the number of fertilized eggs; the number of fry is the number of seedlings about 3cm after the metamorphosis of grouper fry is completed; the survival rate is the ratio of the number of seedlings about 3cm to the number of hatched fish flowers. The statistical results of seedling production are shown in Table 2. The results show that 2 kg of fertilized eggs produced a total of 333,000 fry, with a hatching rate of 69.6-86.7% and a seedling survival rate of 4.5-22.9%.

[0070] Table 2 Statistical results of seedling production of blue-bodied big-spotted grouper in Example 2

[0071]

[0072] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. An artificial breeding method for blue-bodied big-spotted grouper, characterized in that: The steps include: S1. Parent selection: Use healthy blue-bodied grouper over 4 years old and weighing more than 10 kg as reserve parents; S2. Breeding and nutritional fortification of parents: Choose the breeding environment: in a volume of not less than 30m 3 , the reserve parent should be cultured in a breeding pond with a water depth greater than 1.5m. The water temperature of the breeding pond should be 28-31℃, the salinity should be 26-33‰, the pH should be 7.8-8.5, the ammonia nitrogen content should be less than 0.1mg / L, and the breeding density should not exceed 10kg / m 3 The water change frequency is 6 times / day. During the culture process, the light intensity is 3000-4000 lux during the light treatment and less than 30 lux during the dark treatment. Nutritional fortification: In the first six months of spawning / sperm production, the reserve parent needs to be continuously fed with feed A and feed B for nutritional fortification. Feed A is fed once a day, and feed B is fed once every three days. Feed A is freshly-frozen bonito coated with a nutritional enhancer. Each time feed A is fed, the feeding amount of freshly-frozen bonito should be 2-4% of the total weight of the reserve parent. Feed B is freshly-shucked oysters and freshly-frozen squid coated with a nutritional enhancer. The feeding ratio of freshly-shucked oysters and freshly-frozen squid is 4:6, and the feeding amount of freshly-shucked oysters is 2-4% of the total weight of the reserve parent. S3. Parental induction of labor: After nutritional fortification, female parents with obviously enlarged abdomens and male parents with obvious masculine traits were selected for induced spawning; S4. Artificial insemination: On the day of fertilization, collect the eggs of the female parent and the semen of the male parent respectively; add the semen to the clean seawater, mix well, add the eggs, mix well, let stand for 5 minutes, and wash the fertilized eggs with seawater; S5. Hatching of fertilized eggs: Use outdoor pond breeding method or indoor cement pool breeding method for breeding. After 35 days of breeding, fully developed fry are obtained. During the breeding process, the water temperature is 26-35℃, the salinity is 25-33‰, and the ammonia nitrogen is lower than 0.1mg / L.

2. The artificial propagation method according to claim 1, characterized in that: In step S2, the preparation method of feed A is as follows: after thawing 10 kg of chilled fish and draining the water, mix and stir with 200 g of a nutritional enhancer so that the nutritional enhancer adheres to the chilled fish, the nutritional enhancer is obtained by mixing the enhancer and food-grade Tween-80 in a mass ratio of 1:1, and the composition of the enhancer is: 5 parts of Schizochytrium powder, 2 parts of maca powder, 1 part of epimedium, 1 part of folic acid, 2 parts of vitamin C, 1 part of vitamin E, 0.5 parts of vitamin A, 0.2 parts of vitamin B5, 0.2 parts of vitamin D, and 0.2 parts of zinc chloride.

3. The artificial propagation method according to claim 1, characterized in that: In step S3, the specific steps of inducing labor are as follows: 72 hours before the female parent lays eggs, inject 150-200 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogues, and inject 150-200 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogues again 48 hours before laying eggs; 48 hours before the male parent lays sperm, inject oxytocin, the oxytocin is 100-150 IU / kg chorionic gonadotropin and 10-15 μg / kg luteinizing hormone releasing hormone analogues.

4. The artificial propagation method according to claim 1, characterized in that: In step S1, each breeding pond also includes 8-10 mature brown-spotted groupers weighing 6-10 kg, which are used to promote the maturity of the reserve parents.

5. The artificial propagation method according to claim 3, characterized in that: In step S3, after the male parent and the female parent are injected with hormones, they need to be exposed to light for 12 hours and treated in darkness for 12 hours; the light intensity during illumination is 1500-4000 lux, and the light intensity during dark treatment is less than 30 lux.

6. The artificial propagation method according to claim 1, characterized in that: In step S4, the semen collection method is as follows: at 14:00-17:00 on the day of fertilization, use 20ppm eugenol to anesthetize the male parent. After losing balance, place it on the production table, and slowly push down from about 15 cm above the cloaca and 5 cm from the side of the center line of the fish abdomen. When white viscous semen flows out of the cloaca, use a clean dry towel to wipe the cloaca clean, use a sterile 10 ml centrifuge tube to collect the white viscous semen, check the sperm under a microscope with a magnification of 40 times, and retain sperm with a sperm motility greater than 60%.

7. The artificial propagation method according to claim 1, characterized in that: In step S4, the egg collection method is as follows: on the day of fertilization from 19:00 to 23:00, the female parent is placed on the production table and her abdomen is massaged until the eggs flow out and flow into the collection bucket along the conical bag. The eggs need to be artificially inseminated within 10 minutes after collection.

8. The artificial propagation method according to claim 1, characterized in that: In step S1, the total number of reserve parents in each breeding pond during the breeding process is not less than 10.

9. The artificial propagation method according to claim 1, characterized in that: The outdoor pond seedling raising method is carried out as follows: a floating hatching bag is built in the pond, fertilized eggs are placed in the hatching bag for hatching, the egg amount corresponding to each cubic meter of water in the hatching bag is not higher than 0.1 kg, the fry are put into the pond for cultivation when the fry start to ingest exogenous substances, and 1 billion rotifers are put into the pond at the same time, and 10 days after hatching, the nauplii of brine shrimp are fed until they are full; 21 days after hatching, copepods are fed until they are full; 35 days after hatching, metamorphosis is completed and fully developed fry are obtained; the water temperature of the water body in the hatching bag is 26-35°C, the salinity is 25-33‰, the ammonia nitrogen is lower than 0.1 mg / L, and the weight of the fertilized eggs in each pond is 0.4-1.2 kg.

10. The artificial propagation method according to claim 1, characterized in that: The indoor cement pool seedling raising method is carried out as follows: fertilized eggs are placed in a cement pool for hatching, and when the fry begin to ingest exogenous substances, 1 billion rotifers are placed in the cement pool; 10 days after hatching, nauplii of brine shrimp are fed until they are full; 21 days after hatching, copepods are fed until they are full; 35 days after hatching, fully metamorphosed and fully developed fry are obtained; the water temperature of the water body in the hatching bag is 26-35°C, the salinity is 25-33‰, the ammonia nitrogen is lower than 0.1 mg / L, and the weight of the fertilized eggs in each pond is 0.1-0.3 kg.

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