Indoor cultivation method for improving survival rate of larvae and juveniles of horse mackerels

Abstract

The invention discloses an indoor cultivation method for increasing the survival rate of larvae and juveniles of horse mackerels, and relates to the technical field of aquaculture. Pretreated rotifers, shadberry fruit extracts and 2, 4 '-dihydroxychalcone are added in the early larva fish breeding stage and the later larva fish breeding stage, active ingredients such as gulcomannan, proline, chlorogenic acid and potentilla discolor extracts are added in the juvenile fish breeding stage, and meanwhile environmental factors such as illumination and sound wave stimulation are regulated and controlled, so that the juvenile fish breeding efficiency is improved. The survival rate of the horse mackerels and the capability of resisting infection of lactococcus gasseri and vibrio anguillarum can be effectively improved, the investment of the breeding cost is reduced, and the used baits are simple, easy to obtain and simple to prepare.

Description

Technical Field

[0001] This invention relates to the field of aquaculture technology, and in particular to an indoor cultivation method for improving the survival rate of juvenile and young horse mackerel. Background Technology

[0002] Yellow-banded trevally ( Pseudocaranx dentex The yellow-banded trevally (Pterodon spp.), belonging to the genus Pterodon in the family Carangidae, is commonly known in the market as the large jack mackerel, island trevally, or long-striped trevally. It is a typical mid-to-upper-level bony fish. Morphologically, it exhibits typical streamlined features, such as a laterally compressed body, a short caudal peduncle, and a relatively long caudal fin, adapted for rapid swimming. The yellow-banded trevally is large, grows rapidly (adults can reach several kilograms), has firm flesh, and is rich in fat, earning it the title of "King of Trevally." It has become a newly emerging warm-water aquaculture species in recent years. Existing research largely focuses on marine fishing resources and deep-sea cage aquaculture. For example, Chinese patent application number 202511959318.7, published on January 23, 2026, discloses a deep-sea cage aquaculture method for *Triplophysa fulvidraco*. This method uses submersible cages and adjusts the temperature according to seasonal changes (surface water temperature) to maintain the *Triplophysa fulvidraco* at the optimal growth level of 20-25℃ year-round. Feed is delivered via a guide tube at specific points, and a coupled model of "water temperature-feeding amount-allicin-probiotics" is established. Currently, research on the indoor controlled environment for raising larvae and juveniles of *Triplophysa fulvidraco* is still insufficient. Summary of the Invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention proposes an indoor cultivation method to improve the survival rate of juvenile and young jack mackerel, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: An indoor rearing method for improving the survival rate of fry and juvenile mackerel includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, includes 50-80 parts of pretreated rotifers and 10-20 parts of oyster fertilized eggs; (2) Later stage of larval rearing: The water flow rate in the rearing pond is 15~25L / min. When the larvae are 6~10 days old, feed them feed B; when the larvae are 11~14 days old, turn on the green light and feed them feed C. The feed B, by weight, includes 30-60 parts of pretreated rotifers and 20-40 parts of oyster fertilized eggs; The bait C, by weight, includes 20-30 parts white fish meal, 10-15 parts krill meal, 10-12 parts chlorella meal, 2-4 parts fish oil, 1-3 parts Dioscorea opposita fruit extract, 0.5-1.0 parts 2,4'-dihydroxychalcone, 1-3 parts compound vitamins, and 1-3 parts compound minerals. (3) Fry rearing: The water flow rate in the rearing pond is 25~30L / min. When the fry grow to 15~35 days old, green light irradiation and sound wave stimulation are turned on at the same time. After completion, feed D is given. The bait D, by weight, includes 15-25 parts white fish meal, 8-12 parts soybean lecithin, 5-8 parts yeast hydrolysate, 3-6 parts glucomannan, 3-5 parts proline, 0.5-1.5 parts chlorogenic acid, 2-5 parts Agrimonia pilosa extract, 1-3 parts compound vitamins, and 1-3 parts compound minerals.

[0005] Preferably, the entire aquaculture environment is controlled as follows: water temperature 25~27℃, salinity 28~32‰, dissolved oxygen ≥6mg / L, pH 7.8~8.2, ammonia nitrogen <0.1mg / L, and nitrite <0.05mg / L.

[0006] Preferably, the stocking density of fry in the early stage of step (1) is 900~1200 fish / cubic meter.

[0007] Preferably, the feed A mentioned in step (1) includes 60 parts of pretreated rotifers and 15 parts of oyster fertilized eggs by weight; it is fed 5 to 7 times a day, and the daily feeding amount is 3 to 5% of the total body weight of the fish.

[0008] Preferably, the pretreatment of rotifers in steps (1) and (2) involves soaking the rotifers in a pretreatment solution for 5 to 10 hours; the pretreatment solution includes DHA algal oil emulsifier and grapefruit flower extract mixed at a volume ratio of 1 mL: (2 to 3) mL.

[0009] Preferably, the pomelo flower extract is prepared by weighing and crushing dried pomelo flowers, adding 5 to 10 times the weight of purified water, heating and refluxing at 60 to 80°C for 1 to 2 hours, filtering to remove residue, and cooling the filtrate to room temperature.

[0010] Preferably, the stocking density of fry in the later stage of step (2) is 700~900 fish / cubic meter; the wavelength of the green light in steps (2) and (3) is 520~530nm, the light intensity is 500~1000lx, and the irradiation time is 2~5min.

[0011] Preferably, the feed B mentioned in step (2) includes 50 parts of pretreated rotifers and 30 parts of oyster fertilized eggs by weight; it is fed 4 to 5 times a day, and the daily feeding amount is 5 to 8% of the total body weight of the fish.

[0012] Preferably, the compound vitamins were purchased from Shaanxi Jinguan Animal Husbandry Co., Ltd., the compound minerals were purchased from Leshengyuan Biotechnology (Nanjing) Co., Ltd., and the DHA algal oil emulsifier was purchased from Guangzhou Yuanda New Materials Co., Ltd.

[0013] Preferably, the feed C mentioned in step (2) includes, by weight, 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts Dioscorea opposita fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 4 to 5 times a day, and the daily feeding amount is 6 to 9% of the total body weight of the fish.

[0014] Preferably, the preparation method of the *Dipterygium indicum* fruit extract is as follows: weigh fresh *Dipterygium indicum* fruit, dry it in an electric thermostatic drying oven at 50℃, grind and pulverize it, add 8-12 times the weight of purified water, extract at 70-85℃ for 2-3 hours, filter, and concentrate the filtrate to obtain the *Dipterygium indicum* fruit extract.

[0015] Preferably, the stocking density of juvenile fish in step (3) is 500-750 fish / cubic meter; the sound wave stimulation time is 2-5 minutes and the sound wave frequency is 600-800 Hz.

[0016] Preferably, the feed D mentioned in step (3) includes, by weight, 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 2 to 3 times a day, and the daily feeding amount is 7 to 10% of the total body weight of the fish.

[0017] The present invention relates to an indoor culture method for improving the survival rate of juvenile and young horse mackerel, and its application in improving the survival rate of horse mackerel and enhancing their resistance to infection by Lactococcus gasseri and / or Vibrio anguillarum.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: By feeding fish with a diet rich in flavonoids, polyphenols, polysaccharides and natural active substances in stages, the present invention can significantly improve the non-specific immune function of fish. At the same time, it can regulate environmental factors such as light and sound stimulation, which can not only alleviate the stress response of juvenile and large mackerel fish and reduce oxidative damage, but also increase the feed intake of large mackerel fish, thereby improving the survival rate of large mackerel fish and their ability to resist infection by Lactococcus gasseri and Vibrio anguillarum. Attached Figure Description

[0019] Figure 1 This refers to the growth stage of juvenile giant mackerel. Figure 2 Indoor farming of giant jack mackerel. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical content of the present invention, the technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0021] Example 1 An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the indoor rearing environment is controlled at a water temperature of 25℃, a salinity of 28‰, and dissolved oxygen ≥6mg / L, and the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 50 parts pretreated rotifers and 10 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 3% of the total body weight of the fish. The pretreated rotifers were soaked in a pretreatment solution for 5 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL: 2 mL. (2) Later stage of larval rearing: The water flow rate in the rearing pond is 15L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 520nm and a light intensity of 500lx for 2 minutes and then feed them feed C. The feed B, by weight, comprises 30 parts pretreated rotifers and 20 parts fertilized oyster eggs; it is fed four times a day, with the daily feeding amount being 5% of the total fish body weight. The feed C, by weight, comprises 20 parts white fish meal, 10 parts krill meal, 10 parts chlorella meal, 2 parts fish oil, 1 part *Dioscorea opposita* fruit extract, 0.5 parts 2,4'-dihydroxychalcone, 1 part compound vitamins, and 1 part compound minerals; it is fed 4 times a day, with the daily feeding amount being 6% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 25L / min. When the fry grow to 15-35 days old, green light with a wavelength of 520nm and a light intensity of 500lx and sound wave stimulation with a frequency of 600Hz are turned on simultaneously for 2 minutes. After completion, feed D is given. The feed D, by weight, includes 15 parts white fish meal, 8 parts soybean lecithin, 5 parts yeast hydrolysate, 3 parts glucomannan, 3 parts proline, 0.5 parts chlorogenic acid, 2 parts Agrimonia pilosa extract, 1 part compound vitamins, and 1 part compound minerals; it is fed twice a day, with the daily feeding amount being 7% of the total body weight of the fish.

[0022] Example 2 An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the indoor rearing environment is controlled at a water temperature of 27℃, a salinity of 32‰, and dissolved oxygen ≥6mg / L, and the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 80 parts pretreated rotifers and 20 parts fertilized oyster eggs; it is fed 7 times a day, with the daily feeding amount being 5% of the total fish body weight. The rotifers were pretreated by soaking them in a pretreatment solution for 10 hours. The pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 25L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on green light with a wavelength of 530nm and a light intensity of 1000lx for 5 minutes and then feed them feed C. The feed B, by weight, comprises 60 parts pretreated rotifers and 40 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 8% of the total fish body weight. The feed C, by weight, comprises 30 parts white fish meal, 15 parts krill meal, 12 parts chlorella meal, 4 parts fish oil, 3 parts *Dioscorea opposita* fruit extract, 1.0 part 2,4'-dihydroxychalcone, 3 parts compound vitamins, and 3 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 9% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 30L / min. When the fry grow to 15-35 days old, green light with a wavelength of 530nm and a light intensity of 1000lx and sound wave stimulation with a frequency of 800Hz are turned on for 5 minutes. After completion, feed D is given. The feed D, by weight, includes 25 parts white fish meal, 12 parts soybean lecithin, 8 parts yeast hydrolysate, 6 parts glucomannan, 5 parts proline, 1.5 parts chlorogenic acid, 5 parts Agrimonia pilosa extract, 3 parts compound vitamins, and 3 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 10% of the total body weight of the fish.

[0023] Example 3 An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in a pretreatment solution for 8 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 525nm and a light intensity of 800lx for 4 minutes and then feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts *Dioscorea opposita* fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, green light with a wavelength of 525nm and a light intensity of 800lx and sound wave stimulation with a frequency of 700Hz are turned on simultaneously for 4 minutes. After completion, feed D is given. The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0024] Comparative Example 1 The difference between this comparative example and Example 3 is that grapefruit flower extract is not used in the rotifer pretreatment, while the other components and steps remain the same.

[0025] An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in DHA algal oil emulsifier for 8 hours. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 525nm and a light intensity of 800lx for 4 minutes and then feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts *Dioscorea opposita* fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, green light with a wavelength of 525nm and a light intensity of 800lx and sound wave stimulation with a frequency of 700Hz are turned on simultaneously for 4 minutes. After completion, feed D is given. The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0026] Comparative Example 2 The difference between this comparative example and Example 3 is that no extract of Dioscorea opposita fruit is added to bait C, while the other ingredients and steps remain unchanged.

[0027] An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in a pretreatment solution for 8 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 525nm and a light intensity of 800lx for 4 minutes and then feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total body weight of the fish. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, green light with a wavelength of 525nm and a light intensity of 800lx and sound wave stimulation with a frequency of 700Hz are turned on simultaneously for 4 minutes. After completion, feed D is given. The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0028] Comparative Example 3 The difference between this comparative example and Example 3 is that 2,4'-dihydroxychalcone in bait C is replaced with quercetin, while the other components and steps remain unchanged.

[0029] An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in a pretreatment solution for 8 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 525nm and a light intensity of 800lx for 4 minutes and then feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts *Dioscorea opposita* fruit extract, 0.8 parts quercetin, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, green light with a wavelength of 525nm and a light intensity of 800lx and sound wave stimulation with a frequency of 700Hz are turned on simultaneously for 4 minutes. After completion, feed D is given. The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0030] Comparative Example 4 The difference between this comparative example and Example 3 is that chlorogenic acid in bait D is replaced with gallic acid, while the other components and steps remain unchanged.

[0031] An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in a pretreatment solution for 8 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 525nm and a light intensity of 800lx for 4 minutes and then feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts *Dioscorea opposita* fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, green light with a wavelength of 525nm and a light intensity of 800lx and sound wave stimulation with a frequency of 700Hz are turned on simultaneously for 4 minutes. After completion, feed D is given. The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts gallic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0032] Comparative Example 5 The difference between this comparative example and Example 3 is that the extract of Agrimonia pilosa in bait D is replaced with dandelion extract, while the other ingredients and steps remain unchanged.

[0033] An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in a pretreatment solution for 8 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 525nm and a light intensity of 800lx for 4 minutes and then feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts *Dioscorea opposita* fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, green light with a wavelength of 525nm and a light intensity of 800lx and sound wave stimulation with a frequency of 700Hz are turned on simultaneously for 4 minutes. After completion, feed D is given. The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts dandelion extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0034] Comparative Example 6 The difference between this comparative example and Example 3 is that no Agrimonia pilosa extract is added to bait D, while the other ingredients and steps remain the same.

[0035] An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in a pretreatment solution for 8 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B. When the larvae are 11 to 14 days old, turn on the green light with a wavelength of 525nm and a light intensity of 800lx for 4 minutes and then feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts *Dioscorea opposita* fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, green light with a wavelength of 525nm and a light intensity of 800lx and sound wave stimulation with a frequency of 700Hz are turned on simultaneously for 4 minutes. After completion, feed D is given. The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0036] Comparative Example 7 The difference between this comparative example and Example 3 is that green light irradiation is not used in the later stage of larval rearing and green light irradiation and sound wave stimulation are not used in the juvenile rearing, while the other components and steps remain unchanged.

[0037] An indoor rearing method for improving the survival rate of juvenile and young horse mackerel, wherein the rearing environment is controlled at a water temperature of 26℃, a salinity of 29‰, and dissolved oxygen ≥6mg / L, the indoor rearing method includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, comprises 60 parts pretreated rotifers and 15 parts fertilized oyster eggs; it is fed 6 times a day, with the daily feeding amount being 4% of the total fish body weight. The pretreated rotifers were soaked in a pretreatment solution for 8 hours; the pretreatment solution consisted of a mixture of DHA algal oil emulsifier and grapefruit flower extract at a volume ratio of 1 mL:3 mL. (2) Later stage larval rearing: The water flow rate in the rearing pond is 20L / min. When the larvae are 6 to 10 days old, feed them feed B; when the larvae are 11 to 14 days old, feed them feed C. The feed B, by weight, comprises 50 parts pretreated rotifers and 30 parts fertilized oyster eggs; it is fed 5 times a day, with the daily feeding amount being 6% of the total fish body weight. The feed C, by weight, comprises 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts *Dioscorea opposita* fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 5 times a day, with the daily feeding amount being 7% of the total fish body weight. (3) Fry rearing: The water flow rate in the rearing pond is 28L / min. When the fry grow to 15-35 days old, feed them with feed D; The feed D, by weight, includes 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; it is fed 3 times a day, with the daily feeding amount being 8% of the total body weight of the fish.

[0038] Survival rate and morbidity in Experiment Example 1 Examples 1-3 and Comparative Examples 1-7 were set up, and the indoor culture methods of Examples 1-3 and Comparative Examples 1-7 were used respectively. After the juvenile fish were cultured, the survival rate of the large mackerel was counted. The survival rate = (number of surviving juveniles / number of larvae released in the early stage) × 100%. At the same time, the infection of Lactococcus gasseri and Vibrio anguillarum during the culture process was observed. The morbidity rate = (number of diseased fish / number of larvae released in the early stage) × 100%. The results are shown in Table 1. Table 1 Survival rate and morbidity

[0039] Table 1 shows that the indoor cultivation method of the present invention can improve the survival rate of large horse mackerel and its resistance to *Lactococcus gasseri* and *Vibrio anguillarum* infection. Example 3 showed the best experimental results, with an incidence rate of 0.1% for both *Lactococcus gasseri* and *Vibrio anguillarum*, indicating that the present invention can effectively resist the invasion of these bacteria. Comparing Example 3 with Comparative Example 1, it can be seen that after large horse mackerel consumed rotifers soaked in pomelo flower extract, the active substances in the pomelo flower increased the activity of lysozyme and antioxidant enzymes in the fish, activated immune cells such as macrophages, and enhanced the body's ability to clear pathogens. Comparing Example 3 with Comparative Examples 2-6, it can be seen that *Dioscorea opposita* fruit extract, 2,4'-dihydroxychalcone, chlorogenic acid, and *Potentilla anguillarum* extract reduce the risk of bacterial infection by enhancing the fish's non-specific immunity, directly inhibiting the growth of *Lactococcus gasseri* and *Vibrio anguillarum*, and also through antioxidant and anti-stress mechanisms and protecting the intestinal barrier. Even replacing 2,4'-dihydroxychalcone, chlorogenic acid, and Agrimonia pilosa extract with chemically similar substances cannot completely achieve the original effect, indicating that the various feed components in this technical solution work synergistically to enhance the fish's adaptability to the environment and disease resistance.

[0040] Experiment Example 2: Virus Challenge Experiment After the juvenile rearing was completed, 200 large horse mackerel from each treatment group were selected for a challenge experiment. These 200 fish were divided into two groups of 100 fish each. Each large horse mackerel in each group was injected intraperitoneally (inner side of the base of the pelvic fin) with 50 μL of a 1×10⁻⁶ concentration. 6 CFU / mL of Lactococcus garvieae bacterial suspension and 50 μL of 1×10 8 CFU / mL of Vibrio anguillarum was used to continuously observe the fish for 5 days, with the number of dead individuals counted every 12 hours to calculate the survival rate. The results are shown in Table 2, verifying that the cultivation method of this invention can indeed enhance the fish's resistance to Lactococcus gasseri and Vibrio anguillarum, thereby improving the survival rate. Table 2. Effects of poison attack

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An indoor rearing method for improving the survival rate of fry and juvenile horse mackerel, characterized in that, Includes the following steps: (1) Early stage of larval rearing: Raise larvae aged 1 to 5 days in still water. When the larvae grow to 3 to 5 days old, feed them feed A. The feed A, by weight, includes 50-80 parts of pretreated rotifers and 10-20 parts of oyster fertilized eggs; (2) Later stage of larval rearing: The water flow rate in the rearing pond is 15~25L / min. When the larvae are 6~10 days old, feed them feed B; when the larvae are 11~14 days old, turn on the green light and feed them feed C. The bait B, by weight, includes 30-60 parts of pretreated rotifers and 20-40 parts of oyster fertilized eggs; The bait C, by weight, includes 20-30 parts white fish meal, 10-15 parts krill meal, 10-12 parts chlorella meal, 2-4 parts fish oil, 1-3 parts Dioscorea opposita fruit extract, 0.5-1.0 parts 2,4'-dihydroxychalcone, 1-3 parts compound vitamins, and 1-3 parts compound minerals. (3) Fry rearing: The water flow rate in the rearing pond is 25~30L / min. When the fry grow to 15~35 days old, green light irradiation and sound wave stimulation are turned on at the same time. After completion, feed D is given. The bait D, by weight, includes 15-25 parts white fish meal, 8-12 parts soybean lecithin, 5-8 parts yeast hydrolysate, 3-6 parts glucomannan, 3-5 parts proline, 0.5-1.5 parts chlorogenic acid, 2-5 parts Agrimonia pilosa extract, 1-3 parts compound vitamins, and 1-3 parts compound minerals.

2. The indoor cultivation method according to claim 1, characterized in that, In step (1), the stocking density of fry in the early stage is 900~1200 fish / cubic meter.

3. The indoor cultivation method according to claim 1, characterized in that, The feed A mentioned in step (1) includes 60 parts of pretreated rotifers and 15 parts of fertilized oyster eggs by weight; feed 5 to 7 times a day, and the daily feeding amount is 3 to 5% of the total body weight of the fish.

4. The indoor cultivation method according to claim 1, characterized in that, The pretreatment of rotifers in steps (1) and (2) involves soaking the rotifers in a pretreatment solution for 5-10 hours. The pretreatment solution includes DHA algal oil emulsifier and grapefruit flower extract mixed at a volume ratio of 1 mL: (2-3) mL.

5. The indoor cultivation method according to claim 1, characterized in that, In step (2), the stocking density of fry in the later stage is 700-900 fish / cubic meter; the wavelength of the green light in steps (2) and (3) is 520-530 nm, the light intensity is 500-1000 lx, and the irradiation time is 2-5 min.

6. The indoor cultivation method according to claim 1, characterized in that, The feed B mentioned in step (2) includes 50 parts of pretreated rotifers and 30 parts of oyster fertilized eggs by weight; feed 4 to 5 times a day, and the daily feeding amount is 5 to 8% of the total body weight of the fish.

7. The indoor cultivation method according to claim 1, characterized in that, The feed C mentioned in step (2) includes, by weight, 25 parts white fish meal, 11 parts krill meal, 11 parts chlorella meal, 3 parts fish oil, 2 parts Dioscorea opposita fruit extract, 0.8 parts 2,4'-dihydroxychalcone, 2 parts compound vitamins, and 2 parts compound minerals; feed 4 to 5 times a day, with the daily feeding amount being 6 to 9% of the total body weight of the fish.

8. The indoor cultivation method according to claim 1, characterized in that, In step (3), the stocking density of juvenile fish is 500-750 fish / cubic meter; the sound wave stimulation time is 2-5 minutes and the sound wave frequency is 600-800 Hz.

9. The indoor cultivation method according to claim 1, characterized in that, The feed D mentioned in step (3) includes, by weight, 20 parts white fish meal, 9 parts soybean lecithin, 7 parts yeast hydrolysate, 5 parts glucomannan, 4 parts proline, 0.8 parts chlorogenic acid, 3 parts Agrimonia pilosa extract, 2 parts compound vitamins, and 2 parts compound minerals; feed 2-3 times a day, with the daily feeding amount being 7-10% of the total body weight of the fish.

10. The use of the indoor culture method according to any one of claims 1 to 9 in improving the survival rate of large mackerel and enhancing its resistance to infection by Lactococcus gasseri and / or Vibrio anguillarum.

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