A method for domesticating wild larvae of pseudosciaena crocea

Abstract

The application provides a domestication method of wild Pseudosciaena heterura fry, and belongs to the technical field of aquaculture. The application comprises the following steps: capturing wild Pseudosciaena heterura fry, transporting the wild Pseudosciaena heterura fry to a breeding pond for temporary breeding, and then sequentially performing live bait domestication, ice fresh bait domestication, soft granular feed domestication and artificial compound granular feed domestication breeding. The application gradually transitions the wild Pseudosciaena heterura fry to special artificial compound feed by feeding the live bait that is preferred by the wild Pseudosciaena heterura fry, so that the feeding habit and the digestive system of the wild Pseudosciaena heterura fry gradually adapt. The wild Pseudosciaena heterura fry can successfully switch to artificial compound feed after 20 days of domestication, the survival rate is more than 63%, and no batch death phenomenon occurs during the domestication. The application effectively improves the survival rate of the wild Pseudosciaena heterura fry domesticated into artificial breeding condition fry, and provides guarantee for solving the construction of the artificial breeding basic parent fish population.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of aquaculture, and particularly relates to a domestication method of wild Pseudosciaena crocea seedlings of Xizhou group. BACKGROUND

[0002] In China, Pseudosciaena crocea is generally divided into three groups according to population ecology, namely, Min-Yue-Dong group represented by Ningde in Fujian, Daiqu group in Zhoushan, Zhejiang and Xizhou group mainly in the near sea of Xizhou, Guangdong. Among them, Pseudosciaena crocea of Min-Yue-Dong group and Daiqu group has been developed and researched, and formed an industrial scale in Fujian, Zhejiang and other places, while Pseudosciaena crocea of Xizhou group has not been developed and utilized. Pseudosciaena crocea of Xizhou group has a unique advantage in adapting to high sea conditions of deep sea aquaculture, which makes it become a more advantageous variety in the development of deep sea aquaculture in Guangdong. After large-scale breeding, it will effectively solve the industrial development bottleneck that Pseudosciaena crocea of Min-Yue-Dong group in Fujian and Daiqu group in Zhejiang cannot be bred in related areas throughout the year due to poor high-temperature resistance, and is expected to become an important development variety of deep sea aquaculture in the future.

[0003] Due to the destruction of spawning grounds and overfishing, the germplasm resources of wild Pseudosciaena crocea of Xizhou group have shown obvious signs of decline. Maintaining a sufficient number of high-quality Pseudosciaena crocea parents after artificial domestication has become one of the key technical bottlenecks restricting the large-scale artificial breeding and breeding promotion of Pseudosciaena crocea of Xizhou group. Since wild Pseudosciaena crocea of Xizhou group inhabits the middle and lower layers of the near sea, the stress during the catching process is large, and the survival time under artificial breeding conditions is short, making it difficult to build a basic parent fish population for artificial breeding. There are mainly two methods to solve the artificial breeding technology of Pseudosciaena crocea of Xizhou group: one is to capture wild parents, obtain high-quality fertilized eggs through temporary breeding, injection of ovulation hormone, artificial insemination and other series of operations, and then hatch to obtain larvae, and then breed into parents for breeding. The other method is to capture wild Pseudosciaena crocea fry, and make it become fry adapted to the breeding environment through artificial domestication method, and then breed into parents for breeding. However, since wild Pseudosciaena crocea of Xizhou group is highly stressed and sensitive to environmental stimuli such as sound and light, if the captured wild fry is not domesticated, a large number of deaths will occur in a short time. Therefore, providing a domestication method of wild Pseudosciaena crocea fry has a positive significance for the development of artificial breeding of Pseudosciaena crocea of Xizhou group. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a domestication method of wild Pseudosciaena crocea fry of Xizhou group, so as to improve the survival rate of wild Pseudosciaena crocea fry of Xizhou group domesticated as fry under artificial breeding conditions, and provide protection for solving the construction of a basic parent fish population for artificial breeding.

[0005] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical solutions:

[0006] A domestication method of wild Pseudosciaena polyactis fry, comprising the following steps: capturing wild Pseudosciaena polyactis fry, transporting to a breeding pond for temporary breeding, and then sequentially performing live bait domestication, ice fresh bait domestication, soft granular feed domestication, and artificial compound granular feed domestication breeding; the proportion of domestication materials in each domestication stage is gradually reduced until the fry is adapted; the ice fresh bait domestication comprises feeding ice fresh fish meat; the ice fresh fish meat is mackerel, blue round scad or squid.

[0007] Preferably, the live bait domestication comprises feeding live Perinereis aibuhitensis; the daily feeding amount of the live Perinereis aibuhitensis is 10-20% of the body mass of the wild fry.

[0008] Preferably, the ice fresh bait domestication comprises feeding ice fresh fish meat; the daily feeding amount of the ice fresh fish meat is 4-5% of the body mass of the wild fry.

[0009] Preferably, the soft granular feed domestication comprises feeding soft granular feed; the soft granular feed is composed of ice fresh fish meat in the ice fresh bait domestication stage and eel powder compound feed; the daily feeding amount of the soft granular feed is 8-10% of the body mass of the wild fry.

[0010] Preferably, the artificial compound granular feed domestication comprises feeding artificial compound granular feed; the artificial compound granular feed is composed of Pseudosciaena polyactis compound feed, electrolytic multi-vitamins and live probiotic bacteria; the daily feeding amount of the artificial compound granular feed is 8-10% of the body mass of the wild fry.

[0011] Preferably, the domestication and breeding conditions are as follows: water temperature is 23-25 DEG C, pH is 8.2-8.4, dissolved oxygen is 5.5-6.5 mg / L, ammonia nitrogen is 0.01-0.05 mg / L, and illumination is 1000-2000 lux.

[0012] Preferably, the wild fry is wild Pseudosciaena polyactis with a mass of 50-100 g.

[0013] Preferably, during the transportation of the wild fry to the breeding pond, the water temperature is 22-24 DEG C, and the dissolved oxygen is greater than or equal to 5.0 mg / L.

[0014] Preferably, esterified vitamin C is added to the breeding pond; the addition amount of the esterified vitamin C is 4-6 mg / m 3 of water.

[0015] Preferably, during the ice fresh bait domestication, the soft granular feed domestication, and the artificial compound granular feed domestication, residual materials are sucked after feeding the domestication materials in each domestication stage, and water is changed.

[0016] Compared with the prior art, the present application has the following beneficial effects:

[0017] The application provides a domestication method of wild Pseudosciaena polyactis fry, and selects appropriate bait according to the natural feeding habit of Pseudosciaena polyactis, gradually transits to special artificial compound feed by feeding the live bait, and gradually adapts the feeding habit and digestive system of wild Pseudosciaena polyactis, and the survival rate reaches more than 63% after 20 days of domestication, and no batch death phenomenon occurs during domestication. The application effectively improves the survival rate of wild Pseudosciaena polyactis fry domesticated into fry under artificial breeding conditions, and provides guarantee for solving the construction of artificial breeding basic parent fish population. DETAILED DESCRIPTION

[0018] The application provides a domestication method of wild Pseudosciaena polyactis fry, and selects appropriate bait according to the natural feeding habit of Pseudosciaena polyactis, gradually transits to special artificial compound feed by feeding the live bait, and gradually adapts the feeding habit and digestive system of wild Pseudosciaena polyactis, and the survival rate reaches more than 63% after 20 days of domestication, and no batch death phenomenon occurs during domestication. The application effectively improves the survival rate of wild Pseudosciaena polyactis fry domesticated into fry under artificial breeding conditions, and provides guarantee for solving the construction of artificial breeding basic parent fish population.

[0019] The application selects appropriate bait according to the natural feeding habit of Pseudosciaena polyactis, gradually transits to special artificial compound feed by feeding the live bait, and gradually adapts the feeding habit and digestive system of wild Pseudosciaena polyactis, and effectively improves the survival rate of wild Pseudosciaena polyactis fry domesticated into fry under artificial breeding conditions.

[0020] The application sets a trap net on the migration route of Pseudosciaena polyactis in the sea area near Oulu Island in Zhanjiang, Guangdong, the net is composed of a net wall, a net body and a net bag, the total length is 140 meters, the total width is 140 meters, the total height is 5 meters, the mesh of the net wall is 5 cm, and the mesh of the net body is 10 cm. The migration route of Pseudosciaena polyactis is set to intercept and capture fry. The application can effectively improve the survival rate of capture and domestication. The fry in the application is 50-100 g of wild Pseudosciaena polyactis fry, which is easy to domesticate and has high survival rate.

[0021] The application puts the captured wild fry into a live water warehouse and then transports them to a indoor breeding pond. In the application, the wild fry is transported to the indoor breeding pond by a special live fish transport vehicle. During the transportation process, the water temperature is 22-24 DEG C, and the dissolved oxygen is more than 5 mg / L. The application uses pure oxygen to oxygenate the water body, and ice strips are used to control the temperature in the carriage, so as to ensure the survival rate of the wild fry and make the survival rate of the wild fry reach 75%.

[0022] The wild seedlings reach the farm, preferably using erythromycin ointment to smear the damaged part of the fish body, to kill pathogenic bacteria, promote wound healing, and avoid the death of the parent fish. As an implementable way, after the wild seedlings reach the farm, the fish is slowly lifted by hand with a hand net and placed in a plastic bucket containing half a bucket of water, then the fish's eyes are covered with a wet towel, the damaged part of the fish body is smeared with erythromycin ointment, and then slowly transferred to an indoor breeding pond. As an implementable way, the indoor breeding pond has a specification of 5m long*4m wide*1.5m high.

[0023] In the present application, esterified vitamin C is added to the water body in the indoor breeding pond, and the addition amount of the esterified vitamin C is 4-6mg / m 3 Water body. By adding esterified vitamin C to the water body, the present application can alleviate environmental stress, avoid short survival time of wild seedlings due to high stress, and improve the survival rate of wild seedlings. In the specific embodiment of the present application, the esterified vitamin C is purchased from Guangzhou Zhengge Agriculture and Pasture Service Co., Ltd.

[0024] In the present application, the wild seedlings are temporarily raised in the indoor breeding pond for 2-4d, preferably for 3d; and then bait domestication is carried out. In the present application, the wild seedlings are temporarily raised in the oxygenated flowing water, and no feeding is carried out in the temporary raising stage. The wild seedlings are raised at a density of 2-3 tails / m 3 Water body. By temporarily raising the wild seedlings, the present application can reduce the stress of the wild seedlings and improve their survival rate.

[0025] In the present application, the temporary raising and domestication culture conditions of the wild seedlings are as follows: water temperature 23-25℃, salinity 28-30, pH 8.2-8.4, dissolved oxygen 5.5-6.5mg / L, ammonia nitrogen 0.01-0.05mg / L, illumination 1000-2000lux, and flow rate 0.3-0.5m / s. As an implementable way, the present application adjusts the light intensity on the surface of the breeding pond with a sunshade net. The Pseudosciaena polyactis of the Lutjanus bohar species is a middle and lower layer fish, and the light intensity is controlled by shading, which can alleviate the stress of the environment and improve the survival rate of domestication.

[0026] After the temporary raising in the present application, live bait domestication is carried out, and live Perinereis aibuhitensis is fed twice a day. According to the feeding habit of the Pseudosciaena polyactis of the Lutjanus bohar species, the feeding is preferably carried out at 8:00 and 14:00. The live Perinereis aibuhitensis has a body length of 5.0-8.0cm, and the daily feeding amount of the sandworm is 10%-20% of the body weight of the wild seedlings, and the feeding situation of the seedlings is observed. As an implementable way, the remaining sandworms in the pond are fished out at 18:00 every day.

[0027] The live bait domestication in the present application lasts for 4-6d, preferably 5d, and it is found that the wild Pseudosciaena polyactis seedlings actively feed on live Perinereis aibuhitensis and have a food stealing phenomenon. At this time, ice fresh bait domestication can be started.

[0028] The present application carries out ice fresh bait domestication, according to the feeding of Pseudosciaena crocea in Naozhou population has the cluster characteristic, feeds the ice fresh fish meat three times a day, the daily feeding amount of the ice fresh fish meat is 4-5% of the body mass of wild fry; the present application preferably feeds at 8:00, 12:00 and 16:00. The present application cuts the fish meat into blocks, which is convenient for feeding and does not easily pollute the water quality. The ice fresh fish meat of the present application is fresh marine fish purchased in the market, and the ice fresh fish meat is preferably mackerel, blue round sardine or squid. As an implementable way, the present application feeds the fish meat after cleaning, shaving the back muscle, disinfecting with iodine preparation and cutting into blocks.

[0029] The present application feeds the ice fresh fish meat for 1h each time, and then feeds the live Perinereis aibuhitensis, and the feeding amount of the live Perinereis aibuhitensis is reduced day by day. In the present application, the feeding amount of the live Perinereis aibuhitensis in the first 2 days of ice fresh bait domestication is reduced by 25-35% compared with that in the live bait domestication stage, the feeding amount of the live Perinereis aibuhitensis in the third day is reduced by 45-55% compared with that in the live bait domestication stage, the feeding amount of the live Perinereis aibuhitensis in the fourth day is reduced by 75-85% compared with that in the live bait domestication stage, and the wild Pseudosciaena crocea fry in Naozhou population can normally snatch the ice fresh fish meat in the fifth day, at which time the domestication of soft granular feed is started.

[0030] The present application increases the water replacement amount in the ice fresh bait domestication stage, 30min after each feeding of the ice fresh fish meat, the residual bait is sucked and the water is replaced, and the water replacement amount is 100%. As an implementable way, the present application adopts the siphon method to suck the residual bait. The present application ensures that the water quality meets the growth needs of the wild Pseudosciaena crocea fry in Naozhou population by timely removing the residual bait and replacing a large amount of water.

[0031] The present application carries out soft granular feed domestication, and feeds the soft granular feed three times a day, and the daily feeding amount of the soft granular feed is 8-10% of the body mass of wild fry; the present application preferably feeds at 8:00, 12:00 and 16:00. The soft granular feed is composed of ice fresh fish meat in the ice fresh bait domestication stage and eel powder-shaped compound feed, and the added mass of the ice fresh fish meat is 75-85% of the mass of the soft granular feed. As an implementable way, the ice fresh fish meat is stirred and crushed, the eel powder-shaped compound feed is added, water is added and stirred uniformly, and then the mixture is kneaded into 1-2cm strips for feeding. In the specific embodiment of the present application, the eel powder-shaped compound feed is purchased from Fujian Tianma Feed Co., Ltd.

[0032] The soft granular feed is fed for 30 minutes each time, and then the ice fresh fish meat is fed, and the feeding amount of the ice fresh fish meat is reduced day by day. In the present application, on the first day of soft granular feed domestication, the feeding amount of the ice fresh fish meat is reduced by 45-55% compared with that in the ice fresh bait domestication stage, on the second day, the feeding amount of the ice fresh fish meat is reduced by 75-85% compared with that in the ice fresh bait domestication stage, and on the third day, it is observed that the wild Lutjanus argentimaculatus fry can normally snatch the soft granular feed, at this time, the domestication of the artificial compound granular feed is started.

[0033] In the soft granular feed domestication stage of the present application, after each feeding of the soft granular feed is finished, the water is sucked and replaced, and the water replacement amount is 80-100%; as an implementable way, the present application adopts the siphon method to suck the residual bait. The present application ensures that the water quality meets the growth needs of the wild Lutjanus argentimaculatus fry by timely removing the residual bait and replacing a large amount of water. As an implementable way, the present application adds EM bacteria to regulate the water quality according to the water quality, and the EM bacteria are purchased from Hubei Fentian Biotechnology Co., Ltd., and the use method refers to the method recommended by the manufacturer.

[0034] In the present application, the domestication of the artificial compound granular feed is carried out, and the artificial compound granular feed is fed three times a day at fixed time and fixed point, and the daily feeding amount of the artificial compound granular feed is 8-10% of the body weight of the wild fry; the present application preferably feeds at 8:00, 12:00 and 16:00. The artificial compound granular feed is composed of Lutjanus compound feed, electrolytic multi-vitamins and live probiotics, and the mass ratio of the Lutjanus compound feed, electrolytic multi-vitamins and live probiotics is 1000:0.8-1.2:2.8-3.2; as an implementable way, the electrolytic multi-vitamins and live probiotics are dissolved in water, and then adsorbed by the Lutjanus compound feed, and the solid-liquid ratio of the Lutjanus compound feed and the water solution is 50-100g:1mL, preferably 60-80g:1mL, and more preferably 70g:1mL. In the specific embodiments of the present application, the electrolytic multi-vitamins are purchased from Zhejiang Shengda Biotechnology Co., Ltd., the live probiotics are purchased from Cangzhou Yihong Biotechnology Co., Ltd., and the Lutjanus compound feed is produced by Fujian Tianma Technology Group Co., Ltd.

[0035] In the present application, the domestication of the artificial compound granular feed is carried out, and the artificial compound granular feed is fed three times a day at fixed time and fixed point, and the daily feeding amount of the artificial compound granular feed is 8-10% of the body weight of the wild fry; the present application preferably feeds at 8:00, 12:00 and 16:00. The artificial compound granular feed is composed of Lutjanus compound feed, electrolytic multi-vitamins and live probiotics, and the mass ratio of the Lutjanus compound feed, electrolytic multi-vitamins and live probiotics is 1000:0.8-1.2:2.8-3.2; as an implementable way, the electrolytic multi-vitamins and live probiotics are dissolved in water, and then adsorbed by the Lutjanus compound feed, and the solid-liquid ratio of the Lutjanus compound feed and the water solution is 50-100g:1mL, preferably 60-80g:1mL, and more preferably 70g:1mL. In the specific embodiments of the present application, the electrolytic multi-vitamins are purchased from Zhejiang Shengda Biotechnology Co., Ltd., the live probiotics are purchased from Cangzhou Yihong Biotechnology Co., Ltd., and the Lutjanus compound feed is produced by Fujian Tianma Technology Group Co., Ltd.

[0036] The present application domesticates the artificial compound granular feed, and after each feeding of the artificial compound granular feed, the present application carries out the suction of the dirt and the water change, and the water change amount is 80-100%; as an implementable way, the present application adopts the siphon method to suck the residual bait. The present application guarantees that the water quality meets the growth needs of the wild Pseudosciaena crocea by timely removing the residual bait and carrying out the large water change. As an implementable way, the present application adds the EM bacteria to regulate the water quality according to the water quality, and the EM bacteria are purchased from Hubei Fengtian Biotechnology Co., Ltd., and the use method refers to the method recommended by the manufacturer.

[0037] The technical solutions in the present application will be clearly and completely described below in combination with the embodiments in the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0038] Embodiment 1

[0039] Capture of wild fry: a trap net is set on the migration route of Pseudosciaena crocea in the sea area near Oulu Island in Zhanjiang, Guangdong, the net is composed of a net wall, a net body and a net bag, the total length is 140 meters, the total width is 140 meters, the total height is 5 meters, the net mesh of the net wall part is 5 centimeters, and the net mesh of the net body is 10 centimeters. The net is set on the migration route of Pseudosciaena crocea to achieve the purpose of capturing fry. 50-100g wild Pseudosciaena crocea fry is selected, the fry is slowly put into the live water tank by hand net, and oxygen is filled in the live water tank to more than 5mg / L.

[0040] Transport to the culture pond: after the fishing boat returns to the harbor, the wild fry is slowly transferred to a special live fish transport vehicle with a plastic bucket with water, the live fish transport vehicle is oxygenated to more than 5mg / L with pure oxygen, the vehicle compartment is cooled with ice strips, and the water temperature is controlled at 23℃. After arriving at the culture farm, the fish is slowly lifted and put into a plastic bucket filled with half a bucket of water with a hand net, then the fish eyes are covered with a wet towel, the damaged parts of the fish body are smeared with erythromycin ointment, and then the fish is slowly transferred to an indoor culture pond (5m long x 4m wide x 1.5m high).

[0041] Temporary culture and domestication: esterified vitamin C is sprayed in the water in advance, and the dosage per cubic meter of water is 5mg, which is used to alleviate the stress reaction caused by environmental changes. The water quality conditions are as follows: water temperature 25℃, salinity 28, pH 8.3, dissolved oxygen 6.0mg / L, ammonia nitrogen 0.02mg / L, water flow velocity 0.5m / s, temporary culture for 2 days, no feeding during the temporary culture stage, the pool surface is covered with a shading net to adjust the light intensity to 1500lux.

[0042] Live bait acclimation: After the end of the temporary cultivation, live Perinereis aibuhitensis with a body length of 5.0-8.0 cm were put into the tank at 8:00 and 14:00 every day, with a density of 3-5 per square meter. The daily feeding amount of the sandworms was 15% of the body weight of the wild seedlings. The feeding condition of the seedlings was observed. The remaining sandworms in the tank at 18:00 every day were fished out with a fishing net. The water quality condition was controlled in the same way as in the temporary cultivation stage. After 6 days of live bait acclimation, the wild L. niwazhouensis seedlings actively preyed on the sandworms and showed a feeding competition phenomenon. At this time, the acclimation of the ice fresh bait could be started.

[0043] Ice fresh bait acclimation: From the first day of the ice fresh bait acclimation, the daily feeding amount of the ice fresh fish meat was 4% of the body weight of the wild seedlings. The ice fresh fish meat was purchased fresh from the market every day, washed, had the back muscles shaved, disinfected with iodine preparation, cut into 1-2 cm 3 blocks, and fed at fixed points at the edge of the tank at 8:00, 12:00, and 16:00 every day. Each feeding lasted for 1 hour, and then live Perinereis aibuhitensis was fed. The amount of live Perinereis aibuhitensis was gradually reduced every day. On the first and second days of the ice fresh bait acclimation, the amount of live Perinereis aibuhitensis was reduced by 30% compared with that in the live bait acclimation stage. On the third day, the amount of live Perinereis aibuhitensis was reduced by 50% compared with that in the live bait acclimation stage. On the fourth day, the amount of live Perinereis aibuhitensis was reduced by 80% compared with that in the live bait acclimation stage. From the fifth day, it was observed that the wild L. niwazhouensis seedlings could normally prey on the ice fresh fish meat. At this time, the acclimation of the soft granular feed was started.

[0044] During the ice fresh bait acclimation, the water quality condition was controlled in the same way as in the temporary cultivation stage. In addition, the water exchange amount was increased. Half an hour after the end of each feeding of the ice fresh fish meat, the residual bait was sucked and the water was changed by siphoning, with a water exchange amount of 100%.

[0045] Soft granular feed acclimation stage: From the first day of the soft granular feed acclimation, soft granular feed was fed at fixed points at the edge of the tank at 8:00, 12:00, and 16:00 every day. The soft granular feed was mainly composed of the ice fresh fish meat used in the previous stage, which was stirred and crushed to serve as the feed basis, accounting for 80%, and added with powdered eel feed, accounting for 20%. An appropriate amount of water was added, stirred, and kneaded into 1-2 cm strips for feeding. The daily feeding amount of the soft granular feed was 10% of the body weight of the wild seedlings. Each timed feeding lasted for 30 min, and then ice fresh fish meat was fed. On the first day of the soft granular feed acclimation, the amount of fish meat was reduced by 50%. On the second day, the amount of fish meat was reduced by 80%. From the third day, it was observed that the wild L. niwazhouensis seedlings could normally prey on the soft granular feed. At this time, the acclimation of the artificial compound feed was started.

[0046] During the soft granular feed acclimation, the water quality condition was controlled in the same way as in the temporary cultivation stage. In addition, the water exchange amount was increased. After the end of each feeding of the soft granular feed, the sewage was sucked and the water was changed in a timely manner, with a water exchange amount of 80-100%.

[0047] Artificial compound granular feed domestication stage: from the first day of artificial compound granular feed domestication, at 8:00, 12:00 and 16:00 every day, the artificial compound granular feed was fed at the fixed point of the pool. The artificial compound feed for large yellow croaker produced by Fujian Tianma Technology Group Co., Ltd. was purchased, supplemented with electrolytic multivitamin and live probiotic, and the mass ratio of the artificial compound feed for large yellow croaker, electrolytic multivitamin and live probiotic was 1000:1:3. The electrolytic multivitamin and live probiotic were dissolved in water, and then the artificial compound feed for large yellow croaker was fully adsorbed. The material-liquid ratio of the artificial compound feed for large yellow croaker and the water solution was 70g:1mL. After adsorption, the mixture was dried for 10 minutes and then fed. The daily feeding amount of the artificial compound granular feed was 9% of the body weight of the wild fry, and the soft granular feed was fed for 30 minutes after the artificial compound granular feed was fed at a fixed time every day. On the first day of artificial compound granular feed domestication, the feeding amount of the soft granular feed was reduced by 30%, on the second day, the feeding amount of the soft granular feed was reduced by 50%, and on the third day, the feeding amount of the soft granular feed was reduced by 80%. From the fourth day, it was observed that the fry could normally rush to eat the artificial compound granular feed, indicating that the wild Naozhou race large yellow croaker fry domestication was successful.

[0048] During the artificial compound granular feed domestication period, the water quality condition control was the same as that in the temporary breeding stage, and in addition, the water exchange amount was increased. After each feeding of the artificial compound granular feed, the water was immediately sucked and replaced, and the water exchange amount was 80-100%.

[0049] In this example, 150 wild large yellow croaker fry were captured for domestication. After 20 days of domestication, 95 fry that could feed on artificial compound feed were successfully converted, with a survival rate of about 63.3%, and no batch death occurred during the domestication period.

[0050] Example 2

[0051] Capture of wild fry: In the sea area near Naozhou Island in Zhanjiang, Guangdong, a trap net was set on the migration route of Naozhou race large yellow croaker. The net was composed of a net wall, a net body and a net bag, with a total length of 140 meters, a total width of 140 meters, a total height of 5 meters, a net wall part with a mesh size of 5 centimeters, and a net body with a mesh size of 10 centimeters. The net was set to intercept and capture fry on the migration route of Naozhou large yellow croaker. 50-100g wild Naozhou race large yellow croaker fry were selected and slowly put into a live water tank with a hand scoop net, and the tank was oxygenated to more than 5mg / L.

[0052] Transport to the breeding pond: After the fishing boat returned to the harbor, the wild fry were slowly transferred to a special live fish transport vehicle with a plastic bucket with water. The live fish transport vehicle used pure oxygen to increase the oxygen to 6mg / L, and ice strips were used to cool the vehicle compartment to control the water temperature at 22℃. After arriving at the breeding farm, the fish were slowly lifted with a hand scoop net and placed in a plastic bucket containing half a bucket of water. Then, the fish eyes were covered with a wet towel, and the damaged parts of the fish body were smeared with erythromycin ointment before being slowly transferred to an indoor breeding pond (5m long x 4m wide x 1.5m high).

[0053] Temporary acclimation: Sprinkle esterified vitamin C in water in advance, 6 mg per cubic meter of water, to alleviate the stress caused by environmental changes. Water quality conditions: water temperature 24℃, salinity 29, pH 8.4, dissolved oxygen 5.5 mg / L, ammonia nitrogen 0.03 mg / L, water flow rate 0.4 m / s, temporary cultivation for 3 days, no feeding during the temporary cultivation stage, adjust light intensity on the pool surface with shading net, control at 1200 lux.

[0054] Live bait acclimation: After the temporary cultivation, put live Perinereis aibuhitensis at 8:00 and 14:00 every day, body length 5.0-8.0 cm, stocking density 3-5 per square meter, daily feeding amount of sandworms 15% of the body weight of wild seedlings, and observe the feeding behavior of the seedlings. The remaining sandworms in the pool at 18:00 every day are removed with a net. The water quality conditions are controlled the same as in the temporary cultivation stage. After 5 days of live bait acclimation, the wild L. niujiangensis seedlings actively feed on the sandworms and show food competition. At this time, the acclimation of frozen bait can be started.

[0055] Frozen bait acclimation: From the first day of frozen bait acclimation, the daily feeding amount of frozen fish meat is 4% of the body weight of wild seedlings, and the frozen fish meat is fed at 8:00, 12:00 and 16:00 every day at the pool edge. The fish meat is fresh blue scad purchased on the market on the same day, washed, back muscles removed, disinfected with iodine preparation, and cut into 2 cm 3 blocks for feeding. Each feeding lasts for 1 hour, and then live Perinereis aibuhitensis is fed. The amount of live Perinereis aibuhitensis is reduced day by day. On the first and second days of frozen bait acclimation, the amount of live Perinereis aibuhitensis is reduced by 28% compared with the live bait acclimation stage, on the third day, the amount of live Perinereis aibuhitensis is reduced by 52% compared with the live bait acclimation stage, and on the fourth day, the amount of live Perinereis aibuhitensis is reduced by 76% compared with the live bait acclimation stage. From the fifth day, it is observed that the wild L. niujiangensis seedlings can normally compete for frozen fish meat, and at this time, the acclimation of soft granular feed can be started.

[0056] During the frozen bait acclimation, the water quality conditions are controlled the same as in the temporary cultivation stage, and the water exchange amount is increased. Half an hour after each feeding of frozen fish meat is completed, the remaining bait is removed by siphoning and the water is changed, and the water exchange amount is 100%.

[0057] Soft pellet feed domestication stage: from the first day of soft pellet feed domestication, at 8:00, 12:00 and 16:00 every day, soft pellet feed was fed at the pool edge. Soft pellet feed was mainly composed of minced ice-fresh fish meat used in the previous stage as feed basis, accounting for 76%, adding powdered eel feed, accounting for 24%, adding an appropriate amount of water and stirring uniformly, and then kneading into 2cm strips for feeding. The daily feeding amount of soft pellet feed was 10% of the body weight of wild seed fish. Each day, the soft pellet feed was fed for 30 minutes, and then ice-fresh fish meat was fed. On the first day of soft pellet feed domestication, the amount of ice-fresh fish meat was reduced by 48% compared with the ice-fresh bait domestication stage, and on the second day, the amount of ice-fresh fish meat was reduced by 82% compared with the ice-fresh bait domestication stage. From the third day, it was observed that the wild Lutjanus argentimaculatus seed fish could normally feed on soft pellet feed, at which time the domestication of artificial compound feed began.

[0058] During the soft pellet feed domestication period, the water quality conditions were controlled the same as in the temporary cultivation stage, and in addition, the water exchange amount was increased. After each feeding of soft pellet feed, the water was immediately pumped and replaced, and the water exchange amount was 100%.

[0059] Artificial compound pellet feed domestication stage: from the first day of artificial compound pellet feed domestication, at 8:00, 12:00 and 16:00 every day, artificial compound pellet feed was fed at the pool edge. The artificial compound feed for large yellow croaker produced by Fujian Tianma Technology Group Co., Ltd. was purchased, supplemented with electrolytic multi-vitamins and probiotics. The mass ratio of artificial compound feed for large yellow croaker, electrolytic multi-vitamins and probiotics was 1000:1.1:2.8. First, the electrolytic multi-vitamins and probiotics were dissolved in water, and then the artificial compound feed for large yellow croaker was fully adsorbed. The mass ratio of the artificial compound feed for large yellow croaker to the water solution was 80g:1mL. After adsorption, it was dried for 15 minutes and then fed. The daily feeding amount of artificial compound pellet feed was 8% of the body weight of wild seed fish. Each day, the artificial compound pellet feed was fed for 30 minutes, and then soft pellet feed was fed. On the first day of artificial compound pellet feed domestication, the amount of soft pellet feed was reduced by 32%, on the second day, the amount of soft pellet feed was reduced by 48%, and on the third day, the amount of soft pellet feed was reduced by 80%. From the fourth day, it was observed that the seed fish could normally feed on artificial compound pellet feed, indicating that the wild Lutjanus argentimaculatus seed fish domestication was successful.

[0060] During the artificial compound pellet feed domestication period, the water quality conditions were controlled the same as in the temporary cultivation stage, and in addition, the water exchange amount was increased. After each feeding of artificial compound pellet feed, the water was immediately pumped and replaced, and the water exchange amount was 100%.

[0061] In this embodiment, 210 wild large yellow croaker seed fish were captured for domestication. After 20 days of domestication, 140 seed fish successfully converted to feed on artificial compound feed, with a survival rate of about 66.7%, and no batch death occurred during the domestication period.

[0062] Example 3

[0063] The difference between the present example and example 1 is that the wild seedlings are temporarily cultured and domesticated under the conditions of water temperature 25℃, salinity 30, pH 8.2, dissolved oxygen 6.5 mg / L, ammonia nitrogen 0.04 mg / L, illumination 2000 lux, and water flow speed 0.4 m / s.

[0064] In the present example, 180 wild large yellow croaker seedlings are captured for domestication, and 130 seedlings can be successfully converted to feed on artificial compound feed after 20 days of domestication, with a survival rate of about 72.2%, and no batch death phenomenon occurs during the domestication period.

[0065] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which should also be considered within the scope of protection of the present application.

Claims

1. A method for domesticating wild large yellow croaker fry, characterized in that, The process includes the following steps: capturing wild fry of large yellow croaker from Naozhou, transporting them to a rearing pond for temporary holding, and then sequentially acclimating them to live food, frozen food, soft pellet feed, and artificially formulated pellet feed. At each acclimation stage, the proportion of the feed from the previous stage is gradually reduced until the fry adapt. Frozen food acclimation includes feeding them frozen fish meat, such as mackerel, bluefin trevally, or squid. Live food acclimation involves feeding them live sandworms, with the daily feeding amount being 10-20% of the wild fry's body weight. When acclimating to frozen bait, feed frozen fish meat for 1 hour each time, and then feed live sandworms after the feeding. When acclimatizing the fish to soft pellet feed, feed the fish to soft pellet feed for 30 minutes each time, and then feed it fresh fish meat after the feeding is finished. When acclimatizing with artificially formulated pelleted feed, each feeding session should last 30 minutes, followed by feeding with soft pelleted feed.

2. The domestication method according to claim 1, characterized in that, The daily feeding amount of the chilled bait is 4-5% of the body weight of the wild seedlings.

3. The domestication method according to claim 1, characterized in that, The soft pellet feed acclimatization includes feeding soft pellet feed, which is composed of fresh fish meat with eel powder added during the fresh bait acclimatization stage. The daily feeding amount of soft pellet feed is 8-10% of the body weight of wild seedlings.

4. The domestication method according to claim 1, characterized in that, The artificial compounded feed domestication includes feeding artificial compounded feed, which is composed of large yellow croaker compound feed, electrolyte multivitamins and live probiotics. The daily feeding amount of artificial compounded feed is 8-10% of the body weight of wild seedlings.

5. The domestication method according to claim 1, characterized in that, The acclimatization and cultivation conditions are as follows: water temperature 23-25℃, pH 8.2-8.4, dissolved oxygen 5.5-6.5 mg / L, ammonia nitrogen 0.01-0.05 mg / L, and light intensity 1000-2000 lux.

6. The domestication method according to claim 1, characterized in that, The wild seedlings are wild Naozhou large yellow croakers weighing 50-100g.

7. The domestication method according to claim 1, characterized in that, During the transportation of the wild seedlings to the breeding pond, the water temperature was 22-24℃ and the dissolved oxygen was ≥5.0mg / L.

8. The domestication method according to claim 1, characterized in that, Esterified vitamin C is added to the aquaculture tank at a concentration of 4-6 mg / m³. 3 Water bodies.

9. The domestication method according to claim 1, characterized in that, During the domestication processes of fresh bait, soft pellet feed, and artificial compound pellet feed, after feeding the domestication material for each domestication stage, the remaining material is removed and the water is changed.