Full-indoor artificial breeding method for plectropomus leopardus

Abstract

The invention provides a full-indoor artificial breeding method for plectropomus leopardus, and belongs to the technical field of artificial breeding of marine fishes. The full-indoor artificial breeding method for the plectropomus leopardus comprises the steps of earlier-stage incubation of fertilized eggs, incubation in an indoor breeding pond, breeding in an indoor flowing water pond, breeding in an indoor circulating water pond and the like. By regulating and controlling illumination, the irritability of the fries is greatly reduced, the ecological conditions of the fries are effectively optimized, and the health condition and adaptability of the fries are improved. Meanwhile, different types and different total amounts of biological bait combinations are fed in the larva stage, the juvenile stage and the fish stage of the plectropomus leopardus, transition is made in each bait transfer period, enteritis caused by excessive intake of larvae and juveniles and too little intake caused by inadaptation of bait transfer are effectively reduced, and the problem that the survival rate is low in the bait transfer period can be effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of artificial breeding of marine fish, in particular to a method for fully indoor artificial breeding of leopard gill mackerel. Background Art

[0002] The leopard perch (Plectropomus leopardus), also known as the eastern star grouper, belongs to the genus Plectropomus, family Serranidae, order Perciformes. It is a carnivorous fish found in warm coral reefs in subtropical and tropical areas. It boasts strong swimming ability, an elongated body, and vibrant colors. Its distinctive crescent-shaped tail fin makes it particularly beautiful when swimming. Its tender, delicious meat, thin skin, and nutritious texture make it highly valued both economically and ornamentally, making it a popular choice among consumers both domestically and internationally, and generating broad market demand.

[0003] Southeast Asia, particularly Hainan in my country, has dedicated many years to the artificial propagation, seedling cultivation, and aquaculture of leopard gill perch. However, in my country, leopard gill perch seedling cultivation has long relied on a combination of outdoor pond rearing and indoor standardization. Outdoor pond rearing is susceptible to weather changes such as rain, wind, and cooling temperatures, as well as the complex and variable nature of pathogenic microorganisms and fluctuating aquatic environmental factors. This makes the seedlings susceptible to infection and disease outbreaks, or even death. During the transfer of seedlings from outdoor ponds to indoor facilities, the high stress levels significantly increase seedling loss, resulting in low seedling survival rates, significantly reducing the scale of seedling cultivation, and causing significant economic losses. The survival rate of domestic leopard gill perch from newly hatched fry to full-sized seedlings is less than 1%. However, there are no reports on methods for fully indoor artificial breeding of leopard grouper. Although Chinese invention patent "CN115250968A" discloses a method for indoor breeding of grouper, the patent states that fry are not placed in the breeding pond until they are 2-3 days old, and the incubation stage from fertilized eggs to 2-3 day old fry is not described. Therefore, providing a method for artificially controlling the entire process of indoor breeding of leopard grouper, from the early hatching of fertilized leopard grouper eggs to the growth and development of fry, juveniles, and young fish, is of great practical significance for promoting the fully indoor large-scale breeding of leopard grouper fry.

[0004] The invention realizes the growth and development process of fertilized eggs of leopard gill perch from early hatching to larvae, juveniles and young fish. Under fully artificially controlled indoor cultivation conditions, the fertilized eggs are placed in indoor flow-through nursery ponds for cultivation after 14-15 hours of hatching, and then transferred to indoor circulating water ponds for cultivation. This greatly reduces the frequency of diseases and stress losses, and has important practical significance for promoting the full indoor large-scale breeding of leopard gill perch seedlings. Summary of the Invention

[0005] In view of this, the present invention provides a fully indoor artificial seedling breeding method for leopard gill perch, which realizes the growth and development process of leopard gill perch fertilized eggs from early hatching to larvae, juveniles and young fish. Under fully artificially controlled indoor cultivation conditions, the fertilized eggs are put into indoor flow-through seedling breeding ponds for cultivation after 14-15 hours of hatching, and then transferred to indoor circulating water ponds for cultivation, which greatly reduces the frequent occurrence of diseases and stress losses.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a method for fully indoor artificial breeding of leopard gill bass, which is characterized by comprising the following steps:

[0008] S1. Early Incubation of Fertilized Eggs: An egg collection trough was installed outside the broodstock rearing pond and connected to the pond. Fertilized eggs of leopard gill bass were collected in a 500-liter rectangular PE plastic frame egg collection trough. A 60-mesh silk screen was used as an isolation facility for egg incubation, and running water incubation was performed for 14-15 hours. Since the egg collection trough and the broodstock rearing pond were connected by a PE pipe, running water from the broodstock rearing pond flowed in through the pipe opening and out through the bottom of the egg collection trough. The incubation conditions and flow rate in the egg collection trough were the same as those in the broodstock rearing pond.

[0009] S2. Indoor hatching in a nursery pond: Use a 60-mesh screen to scoop out the fertilized eggs from the silk cloth, place them in an egg collector, and use high-salt conditions (approximately 35-36‰) for floating screening. The high-quality fertilized eggs that float up are quickly placed in the indoor flow-through nursery pond for hatching at a density of 1-2 g / m 3 .

[0010] S3. Indoor flow-through pond culture: Fertilized eggs are incubated in still water for the first 15 days after spawning. Fry are hatched in the nursery pond on the second day after spawning, and standardized seedling culture begins. Cultivation conditions are: temperature 26-28°C, pH 7.8-8.2, and salinity 28-30. Micro-flow aquaculture is used after 15 days of incubation.

[0011] Light cycle control: From the time the fertilized eggs are placed in the pond and hatched to the 20th day, artificial light is used for control, with a light intensity of 1500-2000Lx and a light cycle of 24 hours a day. After 20 days, the artificial light source is turned off and the natural light cycle is used for control;

[0012] Biological feed feeding: When the fry reached 3 days old, they began to feed Chlorella + SS rotifers, with the amount of Chlorella added being 3×10 5 cell / mL, add Chlorella 2-3 times a day according to the change of water color, and the feeding density of SS rotifers is 3-5 cells / mL;

[0013] When the larvae were 7 to 8 days old, they were fed with L-type rotifers at a density of 3 per mL;

[0014] When the fry are 11-12 days old and enter the transition period, start to add Artemia to the feed. According to the actual feeding situation of the fry, increase the density of Artemia and reduce the density of Rotifers. Feed different proportions of L Rotifers + Artemia every day;

[0015] When the fry are 18 to 20 days old, feed them Artemia nauplii at a density of 0.5 to 1 per mL. Continue feeding for 18 to 20 days.

[0016] S4 indoor circulating water pool cultivation: When the seedlings in step S3 complete metamorphosis, the seedlings are transferred from the indoor water pool to the indoor circulating water pool for cultivation, and the cultivation conditions are: temperature of 27 to 28 ° C, pH 7.0 to 8.0;

[0017] Light cycle control: artificial light source is used for lighting, and the light intensity is 1000-1500Lx only when feeding. The light source is turned off during daily cultivation;

[0018] Biological bait feeding:

[0019] When the fry are 38 to 40 days old, start adding compound feed to the feed. According to the actual feeding situation of the fry, increase the compound feed and reduce the amount of Artemia feeding according to the acclimatization feeding method, feed Artemia + compound feed in different proportions every day;

[0020] When the fry are 47 days old, a few fry can completely eat the formulated feed;

[0021] When the fry are 65 days old, they can completely eat the compound feed and finally complete the complete conversion of the compound feed, with the feeding ratio being 1.8-2.2% of the fish body weight.

[0022] Preferably, step S4 further comprises screening and dividing the fry into ponds. When the fry grow to a stage of 3 cm to 5 cm in length, screening and dividing the fry into ponds are required, and the screened fry and young fish are poured into their respective ponds according to specifications for intermediate cultivation.

[0023] Preferably, the fertilized eggs placed in the nursery pond are 14-15 hour old fertilized eggs of spiny bass.

[0024] Preferably, the leopard gill perch seedlings are fasted for 1 day the day before being transferred from the indoor flow water pool to the circulating water pool.

[0025] Preferably, in step S3, the dissolved oxygen of the culture water body is ≥6 mg / L, the ammonia nitrogen is ≤0.5 mg / L, and the nitrite is ≤0.05 mg / L.

[0026] Preferably, in step S4, the dissolved oxygen in the culture water body is ≥5 mg / L, the ammonia nitrogen is ≤0.5 mg / L, and the nitrite is ≤0.05 mg / L.

[0027] Preferably, steps S3 and S4 also include disease prevention and control, and the disease prevention and control method is: regularly detecting whether the fry and the breeding water have neuronecrosis virus and iridovirus, so as to achieve early prevention and control; promptly removing and eliminating the fry with adverse symptoms in the nursery pond, and regularly spraying EM bacteria, Bacillus, anti-stress spirit, and vitamin C throughout the pond to increase the fish's immunity, strengthen intestinal health, reduce the stress of the fry, and promote the rapid growth and development of the fry.

[0028] By adopting the above technical solution, the present invention has the following beneficial effects:

[0029] 1. The present invention optimizes and maintains the cultivation environment in the indoor nursery pond by adopting a model of relay cultivation of seedlings in an indoor flowing water pool + an indoor circulating water pool, reduces external interference, maintains constant water quality conditions, reduces stress deaths of fry and juvenile fish, and effectively improves the survival rate of leopard gill bass from fry to juvenile and then to young fish.

[0030] 2. The present invention feeds different types and total amounts of biological bait combinations to leopard gill bass at different stages of larval, juvenile and fish stage, and makes a good transition during each feed change, thereby effectively reducing enteritis caused by excessive intake of larval and juvenile fish and insufficient intake caused by poor adaptation to feed change, and can effectively reduce the problem of low survival rate during the feed change period.

[0031] 3. The present invention carries out standardized cultivation and management during the factory-based fully indoor cultivation period, and starts to put the fertilized eggs into the pond to adapt to the hatching environment before they hatch. It effectively utilizes a variety of fungal preparations and anti-stress agents, and significantly reduces the stress of the fry by regulating light, effectively optimizing the ecological conditions of the fry, improving the health status and adaptability of the fry, and taking strict fry quality control and disease prevention and control measures. At the same time, it reduces the risk of disease and effectively improves the seed production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is the ovipositor (a device for floating fertilized eggs) of the leopard spiny bass.

[0033] Figure 2 These are pictures of fertilized eggs of leopard gill bass at different hatching days.

[0034] Figure 3 These are pictures of the larvae, juveniles and young fish of the leopard gill bass bred in an indoor factory at different hatching days.

[0035] Figure 4 The total length and body height of fertilized eggs of Leopard gill bass at different hatching days. DETAILED DESCRIPTION

[0036] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0037] Example 1

[0038] 1. Establishment of an indoor pre-incubation method for fertilized eggs of Leopard gill bass

[0039] (1) Collection of fertilized eggs: When broodstock are observed to be estrus and chasing each other on the water surface, and their gonads are synchronously developed and mature, they are naturally spawned and fertilized in an indoor flowing water or circulating water culture pond. An egg collection trough is installed outside the broodstock culture pond and connected to the pond. The collected fertilized eggs are placed in a rectangular PE plastic frame with a volume of 500L, and a 60-mesh silk cloth is used as an egg hatching isolation facility.

[0040] (2) Early incubation of fertilized eggs: The egg collection tank is continuously aerated and incubated with flowing water. The water temperature is controlled at 25-27°C during the spawning period. The fertilized eggs need to be incubated in the egg collection tank for about 15 hours.

[0041] 2. Establishment of indoor hatching method for leopard gill bass

[0042] (1) Breeding pond specifications and water preparation

[0043] The nursery pond is a 6×6×1.2m square cement pond with a water depth of 1m. It is aerated with air stones at a density of 1 stone / m 2 The aquaculture water is fresh seawater that has been aerated, precipitated, filtered, and disinfected in the water distribution tank. Before laying eggs, 30 ppm disinfectant (Laizhou Dongli Economic and Trade Co., Ltd. Chemical Plant) must be added to the fresh seawater in the pool. After 24 hours, 200 ppm sodium thiosulfate must be added for neutralization.

[0044] (2) Egg laying and hatching in indoor nursery ponds

[0045] The fertilized eggs that had been incubated for 15 hours in the egg collection tank were collected using a 60-mesh sieve silk scoop. The eggs were then placed in an egg collector and floated under high salt conditions (salinity of 35‰). The high-quality fertilized eggs that floated were quickly placed in the indoor flow workshop nursery pond for egg laying. The egg laying density was 1.5g / m 3 .

[0046] 3. Establishment of a method for cultivating leopard gill bass seedlings in an indoor flow-through workshop

[0047] (1) Cultivation conditions in assembly line workshops

[0048] Cultivation conditions: Water temperature: 26-28°C, salinity: 28, pH: 7.8-8.2, adequate dissolved oxygen in still water (dissolved oxygen ≥ 6 mg / L, ammonia nitrogen ≤ 0.5 mg / L, nitrite ≤ 0.05 mg / L). Before laying eggs, use the air stone to aerate the eggs to ensure adequate oxygen supply (≥ 6.0 mg / L) and improve hatchability. Incubate in still water for the first 15 days after laying eggs. After hatching, use micro-flow aquaculture. Adjust aeration to a lower level (≥ 5.0 mg / L) as appropriate, and do no more than 5% water changes.

[0049] (2) Photoperiod control

[0050] From the time the fertilized eggs begin to hatch in the pond to the 20th day, artificial light is used to control the light intensity, 1800Lx, and the light cycle is 24 hours a day. After 20 days, the artificial light source is turned off and natural light is used with a maximum light intensity of 1500Lx. From the beginning of seedling separation, a light strip should be covered on the top of the workshop roof to reduce the indoor brightness and reduce mutual harm.

[0051] (3) Feeding

[0052] When the fry were 2 to 3 days old, they were fed with Chlorella + SS rotifers every day, with the amount of Chlorella added being 3×10 5 cell / mL, Chlorella was added 2-3 times a day according to the change of water color, and the feeding density of SS rotifers was 4 cells / mL;

[0053] When the larvae are 7 to 8 days old, they are fed with L-type rotifers at a feeding density of 2 per mL;

[0054] When the fry are 11-12 days old and enter the transition period, start to add Artemia to the feed. According to the actual feeding situation of the fry, increase the density of Artemia and reduce the density of Rotifers. Feed different proportions of L Rotifers + Artemia every day;

[0055] When the fry are 18 to 20 days old, feed them Artemia nauplii at a density of 0.5 to 1 per mL for 20 consecutive days.

[0056] (4) Disease prevention and control

[0057] Regularly check the fry and breeding water for the presence of neuronecrosis virus and iridovirus to prevent and control them as early as possible; promptly remove the fry in the nursery pond that show adverse symptoms and eliminate them, and regularly spray EM bacteria, Bacillus, anti-stress spirit, and vitamin C throughout the pond to increase the fish's immunity, strengthen intestinal health, reduce the stress of the fry, and promote the rapid growth and development of the fry.

[0058] (5) Daily management:

[0059] Within 3 days after laying the eggs, sinking eggs should be sucked up to prevent water quality deterioration. After the 20th day of incubation, the bottom of the pond should be cleaned once a day to remove residual bait and excrement from the bottom of the pond to avoid deterioration of water quality and affect the survival and development of fry. During the fry breeding period, attention should be paid to the stimulation of water bodies and external fluctuations on fry, and temperature, noise and light should be avoided to affect the feeding of fry. Water turbidity and ammonia nitrogen indicators in the water should be checked regularly to ensure an excellent growth environment. Fry breeding tools should be strictly disinfected every day and placed in fixed positions. Personnel need to be disinfected before entering the workshop, and the number of people entering the workshop should be controlled.

[0060] (6) Transfer of fry to pond:

[0061] Before and after transferring, disinfection and anti-stress measures should be carried out. Apply anti-stress medicine in advance to reduce the risk of fry mortality due to stress or pathogens caused by scratches. Prepare sufficient buckets of water, add sufficient seawater from the nursery pond, place the collected fry in the buckets, and then quickly transfer them to the prepared indoor circulating water tank for the intermediate incubation process.

[0062] 4. Establishment of a method for cultivating leopard gill bass seedlings in an indoor circulating water workshop

[0063] (1) Cultivation conditions of indoor circulating water workshop

[0064] The circulating water tank was a 6×6×1.2m square cement tank with a water depth of 1m. It was aerated with a 30cm diameter air disc, with two placed in each tank. The cultivation conditions were: temperature 27-28°C, pH 7.0-8.0, dissolved oxygen ≥5mg / L, ammonia nitrogen ≤0.5mg / L, and nitrite ≤0.05mg / L.

[0065] (2) Photoperiod control

[0066] Artificial light source is used for lighting, and the light is turned on only when feeding, with a light intensity of 1300Lx. The light source is turned off during daily cultivation.

[0067] (3) Biological bait feeding

[0068] When the fry were 38 to 40 days old, they were transferred from the indoor flow-through pool to the circulating water pool and began to be fed with Haitong brand compound feed (Santong Bioengineering Co., Ltd.). According to the actual feeding situation of the fry, they were fed with different proportions of Artemia + compound feed every day according to the acclimatization method of increasing compound feed and reducing the amount of Artemia.

[0069] When the fry are 47 days old, a few fry can completely eat the formulated feed;

[0070] When the fry are 65 days old, they can eat the compound feed completely and finally complete the complete conversion of compound feed, with the feeding ratio being 1.8-2.2% of the fish body weight;

[0071] (4) Fry screening and pond separation

[0072] After the fry are transferred to the circulating water pond, when the fry body length reaches 3-5 cm, the screening frequency is once a week; when the fry body length reaches 5-10 cm, the screening frequency is once every 10 days; when the fry body length reaches more than 10 cm, the screening frequency is once a month; by screening the fry and dividing the ponds, the stocking density is maintained constant to prevent the density from being too high, which is conducive to the rapid growth of the fry; disinfection and anti-stress work must be done before and after the pond division to reduce the death of the fry due to stress or infection from scratches on the fish body.

[0073] (5) Disease prevention and control:

[0074] Regularly check the fry and circulating water pool for the presence of neuronecrosis virus and iridovirus to prevent and control them as early as possible; promptly remove the fry in the pond that show adverse symptoms and eliminate them, and regularly spray EM bacteria, anti-stress spirit, and vitamin C to increase the fish's immunity, strengthen intestinal health, reduce the stress of the fry, and promote the rapid growth and development of the fry.

[0075] (6) Daily management:

[0076] Regularly check water quality indicators such as ammonia nitrogen and nitrite, and observe the infection of parasites such as leeches and Ichthyophthirius to ensure a good ecological environment; seedling tools are strictly disinfected every day and placed in fixed positions, and personnel need to be disinfected before entering the workshop.

[0077] The developmental timing and main characteristics of leopard gill bass embryos were recorded. The results are shown in Table 1 and Figure 2 shown.

[0078] Table 1 Developmental timing and main characteristics of leopard gill bass embryos

[0079]

[0080]

[0081] To track the growth of leopard gill perch fry in the factory assembly line, the total length and weight of leopard gill perch fry were measured monthly. The number of leopard gill perch fry remaining was counted, and the survival rate was calculated. Thirty leopard gill perch fry were randomly selected and measured for total length and weight using a 0.1g precision weighing scale and a 1mm ruler. The changes in total length and weight of leopard gill perch fry are shown in Table 2.

[0082] Table 2 Changes in total length and weight of leopard gill perch fry

[0083] Measurement indicators 3 months old 4 months old 5 months old Leopard gill perch total length (cm) 5.7 10.2 16.5 Leopard gill bass weight (g) 6.1 22.3 54.8

[0084] Through these comprehensive measures for fully indoor seedling rearing, no major diseases have occurred during the breeding process. In November 2024, approximately 1 kg of fertilized eggs were produced, yielding approximately 800,000 newly hatched fry. By December, approximately 92,000 fry reached 2 cm in size at 35 days of age, and approximately 34,000 commercial fry reached 15 cm or larger at 5 months of age. The survival rate was approximately 4.25% (5-month-old commercial fry / newly hatched fry), accelerating the large-scale indoor breeding of leopard gill perch.

[0085] Comparative Example 1

[0086] Compared with Example 1, the light cycle control of Comparative Example 1 adopts a combination of natural light from the roof and artificial light source control. The light intensity during seedling cultivation is 2500Lx, which causes severe stress and mutual harm in the seedlings, and also causes a decrease in the immunity of the seedlings, resulting in a high early loss rate of the seedlings.

[0087] Comparative Example 2

[0088] Compared with Example 3, the bait feeding of Comparative Example 2 adopts the following steps:

[0089] When the fry were 2 to 3 days old, they were fed with Chlorella + SS rotifers every day, with the amount of Chlorella added being 3×10 5 cell / mL, Chlorella was added 2 to 3 times a day according to the change of water color, and the feeding density of SS rotifers was 2 cells / mL;

[0090] When the fry are 3 to 5 days old, they are fed with 1 oyster fertilized egg / mL daily;

[0091] When the larvae are 6 to 8 days old, they are fed with L-type rotifers daily at a feeding density of 2 rotifers / mL;

[0092] When the fry are 18 to 20 days old, they are fed with Artemia nauplii at a feeding density of 1 nauplii / mL.

[0093] The feeding density during feeding SS rotifers in Comparative Example 2 was 2 rotifers / mL, while the feeding density of rotifers in Example 1 of the present invention was 4 rotifers / mL. In Comparative Example 2, the feeding density of SS rotifers in the early development stage of the seedlings was low, resulting in insufficient nutritional intake in the early stage of the fry, affecting the survival rate and late development, resulting in a low final survival rate;

[0094] In Comparative Example 2, the L rotifer feeding was switched to when the fry were 6 days old, while in Example 1 of the present invention, the L rotifer addition transition was performed only when the fry were 7 to 8 days old. The L rotifer in Comparative Example 2 was added too early, and since a large number of seedlings could not easily ingest the L rotifer at this time, the seedlings would not adapt well during the feed switching period, resulting in insufficient nutrient intake and inability to obtain more energy, and the seedling drop rate during the feed switching period would increase.

[0095] Comparative Example 3

[0096] Compared with the embodiment of the present invention 1, comparative example 3 adopts still water method to hatch and raise seedlings in 1~10 days after fertilized egg hatching, adopts flowing water method subsequently, premature adding external water source easily causes the introduction and infection of pathogen, because this stage is in the early stage of larval development, immunity is very low, and there is nervous necrosis virus outbreak infection seedling event when hatching 18~19 days old, and leopard gill perch seedlings all die when 20~22 days old.And there is no large-scale disease situation in raising seedlings throughout the present invention, fertilized egg is through cultivating normal development, survives to commercial seedling 15cm and above specification, and when 5 months old, seedling reaches 15cm and above commercial seedling about 34,000, and culture survival rate is about 4.25% (5 months old commercial seedlings / first hatching larval fish), and seedling raising method is technologically advanced, and effect is stable.

[0097] As can be seen from the above examples, the present invention provides a method for artificially raising leopard gill perch seedlings indoors. The method reduces stress on leopard gill perch seedlings and effectively improves the survival rate of leopard gill perch from larvae to juveniles and then to young fish.

[0098] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for artificial breeding of leopard gill bass indoors, characterized in that: The following steps are involved: S1. Early incubation of fertilized eggs: Collected fertilized eggs of Leopard spiny bass were incubated in a flowing water tank for 14-15 hours. S2. Indoor hatching pond: The fertilized eggs of the striped spiny sea bass are placed in the indoor flow workshop hatching pond for hatching, with a stocking density of 1-2g / m 3 ; S3. Indoor flow-through pond culture: The first 15 days after spawning, the fertilized eggs are incubated in still water. Fry hatch from the fertilized eggs on the second day of spawning in the nursery pond, and standardized seedling culture begins. Nursery conditions are: temperature 26-28°C, pH 7.8-8.2, and salinity 28-30. Micro-flow aquaculture is used after 15 days of incubation. Light cycle control: From the time the fertilized eggs are placed in the pond and hatched to the 20th day, artificial light is used for control, with a light intensity of 1500-2000Lx and a light cycle of 24 hours a day. After 20 days, the artificial light source is turned off and the natural light cycle is used for control; Biological feed feeding: When the fry reached 3 days old, they began to feed Chlorella + SS rotifers, with the amount of Chlorella added being 3×10 5 cell / mL, add Chlorella 2-3 times a day according to the change of water color, and the feeding density of SS rotifers is 3-5 cells / mL; When the larvae were 7 to 8 days old, they were fed with L-type rotifers at a density of 3 per mL; When the fry are 11-12 days old and enter the transition period, start to add Artemia to the feed. According to the actual feeding situation of the fry, increase the density of Artemia and reduce the density of Rotifers. Feed different proportions of L Rotifers + Artemia every day. When the fry are 18 to 20 days old, feed them Artemia nauplii at a density of 0.5 to 1 per mL for 18 to 20 days. S4 indoor circulating water pool cultivation: When the seedlings in step S3 complete metamorphosis, the seedlings are transferred from the indoor water pool to the indoor circulating water pool for cultivation, and the cultivation conditions are: temperature of 27 to 28 ° C, pH 7.0 to 8.0; Light cycle control: artificial light source is used for lighting, and the light intensity is 1000-1500Lx only when feeding. The light source is turned off during daily cultivation; Biological bait feeding: When the fry are 38 to 40 days old, start adding compound feed to the feed. According to the actual feeding situation of the fry, increase the compound feed and reduce the amount of Artemia feeding according to the acclimatization feeding method, feed Artemia + compound feed in different proportions every day; When the fry are 47 days old, a few fry can completely eat the formulated feed; When the fry are 65 days old, they can completely eat the compound feed and finally complete the complete conversion of the compound feed, with the feeding ratio being 1.8-2.2% of the fish body weight.

2. The method for artificial seedling rearing of leopard gill perch in an indoor environment according to claim 1, wherein Step S4 also includes screening and dividing the fry into ponds. When the fry grow to a stage of 3cm to 5cm in length, screening and dividing the fry into ponds are required. The screened fry and young fish are poured into their respective ponds according to their specifications for intermediate cultivation.

3. The method for artificial seedling rearing of leopard gill perch in an indoor environment according to claim 1, wherein The water temperature for the early incubation of fertilized eggs is 25-27℃, with continuous aeration and flowing water incubation.

4. The method for artificial seedling rearing of leopard gill perch in an indoor environment according to claim 1, wherein The day before the leopard gill perch fry were transferred from the indoor flow water pool to the circulating water pool, the leopard gill perch fry were fasted for 1 day.

5. The method for artificial seedling rearing of leopard gill perch in an indoor environment according to claim 1, wherein Steps S3 and S4 also include disease prevention and control, and the disease prevention and control method is: regularly testing the fry and the breeding water for the presence of neuronecrosis virus and iridovirus to achieve early prevention and control; promptly removing and eliminating the fry showing adverse symptoms in the nursery pond, and regularly spraying EM bacteria, Bacillus, anti-stress spirit, and vitamin C throughout the pond to increase the fish's immunity, strengthen intestinal health, reduce the stress of the fry, and promote the rapid growth and development of the fry.

6. The method for artificial seedling rearing of leopard gill bass indoors according to claim 1, wherein In step S3, the dissolved oxygen of the culture water body is ≥6 mg / L, the ammonia nitrogen is ≤0.5 mg / L, and the nitrite is ≤0.05 mg / L.

7. The method for artificial seedling rearing of leopard gill perch in an indoor environment according to claim 1, wherein In step S4, the dissolved oxygen in the cultivated water body is ≥5 mg / L, the ammonia nitrogen is ≤0.5 mg / L, and the nitrite is ≤0.05 mg / L.

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