A device and method for off-season breeding of parent fish of pristicon macarellus

Abstract

The application belongs to the field of fishery, and particularly discloses a device and method for off-season breeding of parent fish of Eleutheronema tetradactylum. The device comprises a water storage container and a breeding container connected with the water storage container. The water storage container is connected with a large constant temperature cooler. The breeding container has a plurality of breeding units, each of which is installed with an LED lamp and connected with a small constant temperature cooler. In the device, the seasonal breeding conditions are simulated by adjusting the temperature and light changes. The cold temperature accumulation treatment, temperature rising treatment and temperature jump treatment are sequentially performed. The feed fish is nutritionally enhanced before breeding to supplement the nutrition of the parent fish. Through the device and method, the Eleutheronema tetradactylum can be successfully bred in the non-natural breeding season, and the breeding, breeding and sales in the same year are realized, which is suitable for large-scale promotion.

Description

Technical Field

[0001] This invention belongs to the field of fisheries and relates to a fishery breeding technology, specifically to an apparatus and method for off-season breeding of broodstock of the goby. Background Technology

[0002] *Channa argus*, a native fish species of Northeast China, is prized for its delicious flesh, few bones, and high nutritional value, making it a promising area for development. In recent years, *Channa argus* has been increasingly farmed to meet market demand. However, a common problem encountered in its cultivation is the long hatching period for eggs. Because the parent fish breed in May, the fry only grow to 5-8 cm and 8-15 g in the same year, failing to reach marketable size and thus becoming unsellable. Furthermore, significant overwintering losses occur, requiring surviving fish to be raised for another year until they reach 40-80 g before being ready for market. This seasonal breeding pattern leads to time-limited fry supply, high farming costs, and poor economic returns, hindering the further promotion of *Channa argus* farming.

[0003] If broodstock are bred out of season, starting their breeding season in January or February, the fry can reach over 5cm in length before being stocked in May, allowing for same-year breeding, raising to marketable size, and generating profits within the same year. To ensure the broodstock meet the conditions for out-of-season breeding, a user-friendly device that simulates the breeding environment is essential. Furthermore, during the breeding season, females lay eggs every two weeks, resulting in significant energy and nutrient depletion. Males, needing to protect the eggs, have a limited range of movement (less than 0.5 meters), making feeding difficult and hindering their replenishment. This negatively impacts the health of the broodstock and the quality of the eggs. Therefore, even with a complete out-of-season breeding device, proper nutritional management of the broodstock is still necessary. Normally, 5cm goldfish are fed throughout the breeding process as feeder fish to supplement the nutrition of the parent fish. However, goldfish of about 5cm are all juveniles, and their nutritional structure is not suitable for the parent fish to lay eggs. They lack unsaturated fatty acids, phosphorus, calcium and vitamins. Therefore, in the process of designing the off-season breeding method, in addition to optimizing the environmental simulation conditions, we also proposed a method of fortifying feeder fish nutrition to meet the nutritional needs of the off-season breeding of the parent fish of Goby. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides an apparatus and method for off-season breeding of broodstock of *Ctenopharyngodon geyser*. In this apparatus, the conditions for seasonal breeding are simulated by adjusting temperature and light changes. The broodstock undergoes a series of processes, including cold temperature accumulation treatment, temperature increase treatment, and temperature jump treatment. Before breeding, the feed fish are nutritionally fortified to supplement the broodstock's nutrition, thereby successfully promoting the breeding of *Ctenopharyngodon geyser* during the non-natural breeding season.

[0005] To achieve the above objectives, the specific technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present invention provides an apparatus for off-season breeding of broodstock of the goby, comprising:

[0007] The water storage container is equipped with an inlet and an outlet, and is connected to a large constant temperature heating and cooling unit.

[0008] The breeding container has multiple breeding units arranged side by side, with adjacent breeding units separated by partitions. LED lights are installed on both sides of the partitions. Each breeding unit has a water inlet and a water outlet, and is connected to a small constant temperature heating and cooling unit. Its water inlet is connected to the water outlet of the water storage container.

[0009] Furthermore, each of the breeding units is externally connected to a filter for water filtration during device use.

[0010] Furthermore, the LED light is a natural light source and has a timer switch.

[0011] Secondly, this invention provides a method for off-season breeding of broodstock of *Ctenopharyngodon gerberis* using the aforementioned device. By controlling temperature and light, the breeding environment is artificially simulated, making the physiological state of the broodstock closer to that of the natural environment, thereby stimulating their reproductive activity and making them more likely to enter a breeding state. The method specifically includes the following steps:

[0012] S1. Selection of broodstock: Select broodstock weighing 35-85 grams in good physical condition (females with full abdomens and males that are healthy and energetic), with a female-to-male ratio of 1:1.

[0013] S2. Cold temperature accumulation treatment: Cold temperature accumulation operation can be started when the outdoor temperature is below 0℃ at night. Set the temperature of large and small constant temperature heating and cooling units to 4℃ for 1 month.

[0014] S3. Temperature preparation: After the cold temperature accumulation is completed, use LED lights to irradiate the area at set times every day for 5 days;

[0015] S4. Temperature fluctuation treatment: With the water depth unchanged, set the temperature of the large and small constant temperature heating and cooling machines to 10℃, add ice and drain water into the breeding container every 8 hours, so that the water temperature fluctuates between 0-10℃ for 10 days.

[0016] S5. Breeding environment settings: After the temperature jump is completed, set the temperature of the large and small constant temperature heating and cooling units to 18℃;

[0017] S6. Nutritional fortification management: Feed the goldfish injected with nutrient solution to the parent fish as feed fish, with the feeding quantity being twice the number of parent fish, and the feeding frequency being twice a day for one month.

[0018] Furthermore, in step S2, the water depth in the breeding container is set at about 20cm, and the stocking density of *Cyprinus gerberis* is 3 fish / liter; during the cold accumulated temperature treatment period, no light or oxygenation is required, and the water is changed once a week.

[0019] Furthermore, in step S3, the heating preparation operation involves using LED lights to irradiate the water for 12 hours daily, and the water depth and temperature during the heating preparation period are the same as those for the cold temperature accumulation treatment.

[0020] Furthermore, in step S4, during the temperature jump treatment, LED lights are used to irradiate the water for 13 hours daily, and the water is changed once a week.

[0021] Furthermore, in step S5, the water depth is set to 50cm, and four ceramic plates are placed at an angle near the four corners in each breeding unit of the breeding container to provide hiding space for the parent fish. The parent fish will lay their eggs on the ceramic plates. This arrangement can improve the quality of the fish eggs and facilitate their collection. LED lights are used to illuminate the water for 14 hours a day, and the water is continuously changed and aerated.

[0022] Further, in step S6, the nutrient solution injection dosage for the feed fish is 0.2 mL. The nutrient solution formula consists of 30% soybean lecithin, 25% cod liver oil, 10% vitamin premix, 5% calcium chloride, 25% physiological saline, 5% solvent, and 1-3 mg / L metronidazole. Wherein, "%" represents mass fraction; the vitamin premix composition is vitamin C:vitamin E = 2:1 (mass ratio); the solvent composition is emulsifier-gum arabic: stabilizer-glycolipid: pH adjuster-citric acid = 15:2:1 (mass ratio). This formula, by adding a high proportion of soybean lecithin and cod liver oil, improves the nutritional status of the broodstock through the food chain; the addition of metronidazole avoids bacterial infection caused by mechanical damage during injection into the goldfish and prevents bacterial infection during the broodstock production process.

[0023] The present invention has the following beneficial effects:

[0024] 1. This invention innovatively simulates the conditions for seasonal breeding through a process of cold temperature accumulation treatment, temperature rise treatment, temperature jump treatment, and breeding environment setting. This effectively stimulates the reproductive activity of the parent fish, bringing them into a breeding state. The absence of any step in this process (especially the temperature jump treatment) may lead to the failure of the parent fish to reproduce.

[0025] 2. By using the off-season breeding device and method of the present invention, the breeding period of parent fish is advanced from May under natural conditions to January-February, so that the fry in the same year can grow to commercial size, realizing breeding, raising and selling in the same year, thereby significantly shortening the breeding cycle and improving the breeding efficiency.

[0026] 3. The breeding device of this invention is simple to operate and has detailed steps. It can successfully induce the breeding of Goby gracilis during non-natural breeding seasons, thereby enabling large-scale breeding and promotion.

[0027] 4. This invention is based on the design of a nutrient solution formula, and by injecting the nutrient solution into feed fish to feed broodstock, it meets the high nutritional needs of broodstock during the breeding period, thereby improving the production performance of broodstock and the quality of fish eggs. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the apparatus for off-season breeding of broodstock of the Goby in Example 1.

[0029] Figure 2 This is a schematic diagram of the placement of the ceramic plates in Example 1.

[0030] In the diagram: 1: Water storage container; 2: Large constant temperature heating and cooling unit; 3: First water inlet; 4: First water outlet; 5: Second water inlet; 6: Second water outlet; 7: Breeding container; 8: LED light; 9: Small constant temperature heating and cooling unit; 10: Filter; 11: Water outlet pipe; 12: Ceramic plate.

[0031] Figure 3 This is a diagram of the vent holes of the female and male *Gnaphalium affine* parent fish before off-season breeding in Example 1.

[0032] Figure 4 This is a diagram showing the changes in fish eggs after off-season breeding of the parent fish of *Gnaphalium affine* in Example 1.

[0033] Figure 5 This is a comparison of the test results of off-season breeding of broodstock of *Gnaphalium affine* and conventional seasonal breeding of broodstock of *Gnaphalium affine* in Example 1, in terms of fertilization rate, eye development rate, hatching rate, and surfacing rate.

[0034] Figure 6 This is the experimental result of the effect of different doses of nutrient solution-fortified feed fish on the sexual maturity index of parent fish in Example 3.

[0035] Figure 7 This is the experimental result of the effect of different doses of nutrient solution-fortified feed fish on the hormone levels of parent fish in Example 4.

[0036] Figure 8 This is the experimental result of the effect of different doses of nutrient solution-fortified feed fish on the total spawning of parent fish in Example 5.

[0037] Figure 9 This is the experimental result of the effect of different doses of nutrient solution-fortified feed fish on the fertilization rate of parent fish eggs in Example 6.

[0038] Figure 10 This is the experimental result of the effect of different doses of nutrient solution-fortified feed fish on the eye development rate of parent fish eggs in Example 7.

[0039] Figure 11 This is the experimental result of the effect of feed fish fortified with different doses of nutrient solution on the hatching rate of parent fish and fry in Example 8.

[0040] Figure 12 This is the experimental result of the effect of feed fish fortified with different doses of nutrient solution on the buoyancy rate of parent fish and fry in Example 9. Detailed Implementation

[0041] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0042] Example 1: An apparatus and method for off-season breeding of broodstock of *Cyprinus gracilis*.

[0043] The device for off-season breeding of *Ctenopharyngodon gerberis* broodstock is as follows: Figure 1 As shown, the system includes a water storage container 1 and a breeding container 7. The water storage container 1 has a first water inlet 3 and a first water outlet 4, and is externally connected to a large constant temperature heating and cooling unit 2. The breeding container 7 has an open top and multiple breeding units arranged side by side. Adjacent breeding units are separated by partitions. LED lights 8 are installed on both sides of the partitions and the outermost two outermost breeding units. The LED lights 8 are foldable LED lights, which are natural light sources and have timer switches. Each breeding unit has a second water inlet 5 and a second water outlet 6, and is externally connected to a small constant temperature heating and cooling unit 9 and a small filter 10. The second water inlet 5 is connected to the first water outlet 4 through a pipe, and the second water outlet 6 is connected to a water outlet pipe 11.

[0044] The method for off-season breeding of broodstock of *Channa argus* using the above-mentioned device includes the following steps:

[0045] S1. Selection of parent fish: In January and February, parent fish weighing 35-85 grams and in good condition were selected and placed in the breeding container 7 of the device. The ratio of females to males was 1:1. The female fish had full abdomens and the male fish were healthy and energetic.

[0046] S2. Cold Accumulation Temperature Treatment: Cold accumulation temperature treatment can begin when the outdoor temperature drops below 0℃ at night, and lasts for one month. The cold accumulation temperature treatment involves setting the water depth of the breeding container 7 to about 20cm, setting the temperature of the large and small constant temperature heating and cooling machines to 4℃, and then transferring water to the breeding container 7 after the water temperature in the storage container 1 reaches 4℃ and maintaining the water temperature at 4℃. The stocking density of *Cyprinus gerberis* is 3 fish / liter. During this period, no light or oxygenation is required, and the water is changed once a week.

[0047] S3. Temperature preparation: After the cold accumulation temperature is completed, a temperature preparation operation is carried out for 5 days. The temperature preparation operation involves using LED lights 8 for 12 hours a day at set times. During this period, the water depth and water temperature are the same as the cold accumulation temperature treatment conditions.

[0048] S4. Temperature fluctuation treatment: With the water depth unchanged, set the temperature of the large and small constant temperature heating and cooling machines to 10℃, add ice and drain water into the breeding container 7 every 8 hours to make the water temperature fluctuate between 0-10℃; during this period, use LED lights 8 to irradiate for 13 hours every day, and change the water once a week.

[0049] S5. Breeding Environment Setup: After the temperature jump is complete, set the water depth to 50cm and the temperature of both the large and small constant temperature heaters to 18℃; place each breeding unit in breeding container 7 at an angle near the four corners (e.g., Figure 2 (As shown) 4 ceramic plates 12; During this period, LED lights were used for 14 hours a day for regular illumination, and water was continuously changed and oxygenated.

[0050] S6. Nutritional fortification management: Prepare the nutrient solution according to the following formula: 30% soybean lecithin, 25% cod liver oil, 10% multivitamin premix (vitamin C: vitamin E = 2:1), 5% calcium chloride, 25% physiological saline, 5% solvent (emulsifier - gum arabic: glycolipid: citric acid = 15:2:1), and 1-3 mg / L metronidazole; feed the parent fish with 0.2 mL of this nutrient solution, twice the number of parent fish, twice a day for one month, and complete the off-season breeding operation in April.

[0051] In this embodiment, the vent holes of the female and male *Ctenopharyngodon geranium* broodstock before off-season breeding are as follows: Figure 3 As shown in the diagram, the changes in fish eggs after off-season breeding are as follows: Figure 4 As shown, the broodstock reproduced successfully and the eggs were of good quality. The fertilization rate, eye development rate, and hatching rate were calculated, and the results are as follows: Figure 5 As shown, there are no significant differences in fertilization rate, eye emergence rate, hatching rate, and surfacing rate between seasonal and off-season breeding, indicating that off-season breeding of *Gnaphalium affine* broodstock is effective and suitable for large-scale promotion.

[0052] Example 2: Experiment on the effects of different doses of nutrient-fortified feed fish on the nutritional composition of broodstock.

[0053] Twelve healthy, disease-free feedfish of similar size (3.08±0.16 cm) were randomly divided into four groups with three replicates per group. Different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL) of nutrient solution were injected intramuscularly into the feedfish of different groups for nutritional fortification. After 24 hours, whole fish were harvested for nutrient composition analysis. The nutrient composition of the whole fish was determined using national standard methods. Moisture content was determined by drying at 105℃ (GB / T 6435-2014); crude protein was determined by the Kjeldahl method (GB / T 6432-2018); crude fat was determined by Soxhlet extraction (GB / T 5009.6-2016); and crude ash was determined by calcination at 550℃ (GB / T 5009.4-2016).

[0054] The results are shown in Table 1. With increasing nutrient solution injection dosage, the crude protein and crude fat content of the whole fish showed an increasing trend, while the moisture and crude ash content showed a decreasing trend. Compared with the control group, the crude protein and crude fat content of the feed fish injected with 0.1, 0.2, and 0.3 mL of nutrient solution were significantly increased, while there were no significant differences in moisture and crude ash content among the groups. Considering both the nutritional composition of the whole fish and the cost of the nutrient solution, an injection dosage of 0.2 mL was selected as the optimal dosage.

[0055] Table 1. Effects of different nutrient solution dosages on the whole nutrient composition of feedfish

[0056]

[0057] Example 3: Effect of different doses of nutrient-fortified feed on the sexual maturity index of broodstock.

[0058] Two hundred and eighty-eight male and female *Channa argus* broodstock of similar size and good health (63.19±8.43 mm) after off-season breeding were selected and randomly divided into four groups (female:male = 1:1), with three replicates per group and 24 fish per replicate. The broodstock were fed with feed fish fortified with different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL). After 21 days, six females and six males were randomly selected from each replicate to measure their body weight, followed by the weight of their gonads. The sexual maturity coefficient (SMC) of the broodstock was calculated using the formula: SMC = (gona weight / empty shell weight) × 100%.

[0059] The results are as follows Figure 6 As shown, with the increase of the nutrient solution injection dosage, the sexual maturity coefficients of both female and male broodstock fish showed an upward trend, stabilizing at 0.2 mL. Compared with the control group, the sexual maturity coefficients of female fish fed with 0.1, 0.2, and 0.3 mL of nutrient solution were significantly higher, while the sexual maturity coefficients of male fish fed with 0.2 and 0.3 mL of nutrient solution were significantly higher. In conclusion, feeding broodstock fish with 0.2 mL of nutrient solution is the optimal method.

[0060] Example 4: Experiment on the effect of different doses of nutrient solution-fortified feed on hormone levels in broodstock fish

[0061] Different groups of broodstock were fed with feed fortified fish at different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL). After 21 days, three female and three male fish were randomly selected from each replicate, anesthetized, and blood was collected from the tail vein. Serum samples were obtained by centrifugation at 3000 r / min for 10 min. The estradiol (ml003452) content in female fish and the testosterone (ml025781) content in male fish were determined using a Shanghai enzyme-linked ELISA kit.

[0062] The results are as follows Figure 7 As shown, with the increase of the nutrient solution injection dosage, the serum estradiol content of female broodstock and the testosterone content of male broodstock both showed an upward trend. Compared with the control group, the serum testosterone content of female and male broodstock fed with 0.2 and 0.3 mL of nutrient solution fortified feed was significantly higher. In conclusion, feeding broodstock with 0.2 mL of nutrient solution is the optimal method.

[0063] Example 5: Experiment on the effect of different doses of nutrient solution-fortified feed on the total spawning of broodstock.

[0064] Different groups of broodstock were fed with feeder fish fortified with different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL). After the breeding season, the total number of eggs laid in each group was recorded.

[0065] The results are as follows Figure 8 As shown, the total spawning of broodstock increased with increasing nutrient solution injection dosage. Compared with the control group, the total spawning of broodstock fed with 0.1, 0.2, and 0.3 mL of nutrient solution-fortified feed significantly increased. Considering both total spawning and nutrient solution cost, the 0.2 mL injection dosage was the optimal choice.

[0066] Example 6: Experiment on the effect of different doses of nutrient solution-fortified feed fish on the fertilization rate of broodstock eggs

[0067] Different groups of broodstock were fed with feed fish fortified with different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL). After the breeding season, the fertilization status of the eggs in each group was recorded, and the fertilization rate was calculated. The calculation formula is: number of fertilized eggs / total number of eggs laid × 100%.

[0068] The results are as follows Figure 9As shown, the fertilization rate of fish eggs increased with the increase of the nutrient solution injection dosage, and then stabilized at 0.2 mL. Compared with the control group, the fertilization rate of fish eggs fed with nutrient solution fortified with 0.2 and 0.3 mL was significantly higher. In conclusion, feeding broodstock with 0.2 mL of nutrient solution is the optimal method for feeding fish.

[0069] Example 7: Experiment on the effect of different doses of nutrient solution-fortified feeder fish on the eye development rate of broodstock eggs.

[0070] Different groups of broodstock were fed with feeder fish fortified with different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL). After the breeding season, the eye development of eggs in each group was recorded, and the eye development rate was calculated. The calculation formula is: number of eyed eggs / total number of eggs laid × 100%.

[0071] The results are as follows Figure 10 As shown, the eye-seeping rate of fish eggs increased with the increase of the nutrient solution injection dosage. Compared with the control group, the eye-seeping rate of fish eggs fed with 0.1, 0.2, and 0.3 mL of nutrient solution-fortified feed was significantly higher. Considering both eye-seeping rate and nutrient solution cost, the 0.2 mL injection dosage was the optimal choice.

[0072] Example 8: Experiment on the effect of feed fish fortified with different doses of nutrient solution on the hatching rate of broodstock and fry.

[0073] Different groups of broodstock were fed with feeder fish fortified with different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL). After the breeding season, the hatching status of the larvae in each group was recorded, and the hatching rate was calculated. The calculation formula is: (Number of hatched larvae / Total number of eyed eggs) × 100%.

[0074] The results are as follows Figure 11 As shown, the eye-seeping rate of fish eggs increased with the increase of the nutrient solution injection dosage, and then stabilized at 0.2 mL. Compared with the control group, the eye-seeping rate of fish eggs fed with nutrient solution fortified with 0.2 and 0.3 mL was significantly higher. In conclusion, feeding broodstock with 0.2 mL of nutrient solution is the optimal method for feeding fish.

[0075] Example 9: Experiment on the effect of different doses of nutrient-fortified feeder fish on the buoyancy rate of broodstock and fry.

[0076] Different groups of broodstock were fed with feed fish fortified with different doses (0 mL, 0.1 mL, 0.2 mL, 0.3 mL). After the breeding season, the surfacing rate of the larvae in each group was recorded, and the surfacing rate was calculated. The calculation formula is: (Number of surfacing larvae / Total number of ruptured larvae) × 100%.

[0077] The results are as follows Figure 12As shown, the buoyancy rate of larvae increased with the increase of the nutrient solution injection dosage, and then stabilized at 0.2 mL. Compared with the control group, the buoyancy rate of larvae fed with nutrient solution fortified with 0.2 and 0.3 mL was significantly higher. In conclusion, feeding broodstock with 0.2 mL of nutrient solution is the optimal method for feeding larvae.

[0078] Example 10: Experiment on the effects of different nutrient solution compositions on feeder fish

[0079] This example tested the effects of two nutrient solution formulations on the nutritional composition of feed fish:

[0080] Formula 1: 30% soybean lecithin, 25% cod liver oil, 10% vitamin premix, 5% calcium chloride, 25% physiological saline, and 5% solvent;

[0081] Formula 2: 20% soybean lecithin, 15% cod liver oil, 15% multivitamin premix, 5% calcium chloride, 40% physiological saline, and 5% solvent;

[0082] Nutritional composition tests were conducted on feedfish injected with two different nutrient solutions. The results are shown in Table 2. Compared with Formula 1, the feedfish injected with Formula 2 showed a significant decrease in crude protein and crude fat, a significant increase in moisture, while the crude ash content remained unchanged. This indicates that a high proportion of soybean lecithin and cod liver oil has a better effect on feedfish in the short term, thus better improving the nutritional status of the broodstock.

[0083] Table 2. Effects of different proportions of nutrient solution components on the whole nutrient composition of feedfish.

[0084]

[0085] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. Any changes made by those skilled in the art after reading the specification of the present invention, as long as they are within the scope of the claims of the present invention, will be protected by patent law.

Claims

1. A method for off-season breeding of broodstock of *Cyprinus gracilis*, characterized in that: This method utilizes an apparatus, the structure of which includes: The water storage container is equipped with an inlet and an outlet, and is connected to a large constant temperature heating and cooling unit. A breeding container has multiple breeding units arranged side by side, with adjacent breeding units separated by partitions. LED lights are installed on both sides of the partitions. Each breeding unit has a water inlet and a water outlet, and is connected to a small constant temperature heating and cooling unit. Its water inlet is connected to the water outlet of the water storage container. The method for off-season breeding of broodstock of *Cyprinus gracilis* using the aforementioned device includes the following steps: S1. Selection of broodstock: Select broodstock weighing 35-85 grams in good physical condition, with a female-to-male ratio of 1:1; S2. Cold temperature accumulation treatment: Cold temperature accumulation operation can begin when the outdoor temperature is below 0℃ at night. Set the temperature of large and small constant temperature heating and cooling units to 4℃ for one month. S3. Temperature preparation: After the cold temperature accumulation is completed, use LED lights to irradiate the area at set times every day for 5 days; S4. Temperature fluctuation treatment: With the water depth unchanged, set the temperature of the large and small constant temperature heating and cooling machines to 10℃, add ice and drain water into the breeding container every 8 hours, so that the water temperature fluctuates between 0-10℃ for 10 days. S5. Breeding environment settings: After the temperature jump is completed, set the temperature of both the large and small constant temperature heating and cooling units to 18℃; S6. Nutritional Enhancement Management: Feed the goldfish injected with nutrient solution to the parent fish as feed fish, with the feeding quantity being twice the number of parent fish, and feeding frequency twice a day for one month.

2. The method for off-season breeding of *Channa argus* broodstock according to claim 1, characterized in that: In the device, each of the breeding units is externally connected to a filter.

3. The method for off-season breeding of *Ctenopharyngodon gerberis* broodstock according to claim 1, characterized in that: In the device, the LED light is a natural light source and has a timer switch.

4. The method for off-season breeding of *Channa argus* broodstock according to claim 1, characterized in that: In step S2, the water depth in the breeding container is set at about 20 cm, and the stocking density of *Cyprinus gerberis* is 3 fish / liter. During the cold temperature accumulation treatment period, no light or oxygenation is required, and the water is changed once a week.

5. The method for off-season breeding of *Ctenopharyngodon gerberis* broodstock according to claim 4, characterized in that: In step S3, the heating preparation operation involves using LED lights to irradiate the water for 12 hours every day. During the heating preparation period, the water depth and water temperature are the same as those for the cold accumulated temperature treatment.

6. The method for off-season breeding of *Channa argus* broodstock according to claim 5, characterized in that: In step S4, during the temperature jump treatment, LED lights are used to irradiate the water for 13 hours daily, and the water is changed once a week.

7. The method for off-season breeding of *Ctenopharyngodon gerberis* broodstock according to claim 6, characterized in that: In step S5, the water depth is set to 50 cm, and four ceramic plates are placed at an angle near the four corners in each breeding unit of the breeding container; LED lights are used to illuminate the water for 14 hours every day, and water is continuously changed and aerated.

8. The method for off-season breeding of *Channa argus* broodstock according to claim 7, characterized in that: In step S6, the nutrient solution injected into the feed fish is 0.2 mL. The nutrient solution formula is 30% soybean lecithin, 25% cod liver oil, 10% vitamin premix, 5% calcium chloride, 25% physiological saline, 5% solvent, and 1-3 mg / L metronidazole.

9. The method for off-season breeding of *Ctenopharyngodon gerberis* broodstock according to claim 8, characterized in that: The nutrient solution contains a vitamin premix with a ratio of vitamin C to vitamin E of 2:1 and a solvent with a ratio of gum arabic to glycolipid to citric acid of 15:2:1.

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