Method for artificially regulating all-year natural spawning of tetra fish fingerlings

Abstract

The application discloses a kind of artificial regulation and control methods of four-fingered jack male fish full year natural spawning, it is related to aquatic breeding technical field, comprising the following steps: (1) batch spawning management of parent fish;(2) compound environment regulation;(3) stage type nutrition reinforcement;(4) postpartum recovery of parent fish;(5) probiotics synergistic regulation water quality.The application uses environment, biology, nutrition, parent fish management and other compound management methods to regulate four-fingered jack male fish gonad development, breaks the seasonal restriction of short breeding period of four-fingered jack, achieves full year natural spawning, improves the spawning quantity of parent fish, fertilization rate, hatching rate and postpartum parent fish survival rate, also synchronously solves the low overwintering survival rate of four-fingered jack and other industrial problems.Compared with prior art, the spawning quantity of four-fingered jack male fish of the application increases by 82%, the fertilization rate and hatching rate are all increased by 30%, and the postpartum parent fish survival rate is increased by 15%.

Description

Technical Field

[0001] This invention belongs to the field of aquatic breeding technology, specifically relating to an artificial regulation method for the year-round natural spawning of broodstock of the four-fingered mackerel. Background Technology

[0002] The four-fingered mackerel (Sinibotia spp.) is a warm-water, medium-sized fish belonging to the family Sinibotidae in the order Mugilidae, widely distributed in the northern Indian Ocean and the western Pacific Ocean. The spawning period of the four-fingered mackerel in its natural marine environment is relatively short, lasting only from late March to early May, approximately 50 days. To address the issue of the short spawning period, scientists have been conducting research to find better artificial control methods to extend its spawning cycle and promote the large-scale development of the industry. For example, Chinese patent CN113812356A discloses a method for the all-season cultivation of four-fingered mackerel broodstock, allowing the breeding season to last from mid-March to mid-November. This method includes selectively constructing reproductive populations within the cultured population, cultivating broodstock in culture ponds, feeding the broodstock with special mackerel feed, overwintering, pre-spawning cultivation, and spawning. Summary of the Invention

[0003] The purpose of this invention is to provide an artificial regulation method for the year-round natural spawning of broodstock of the four-fingered mackerel, breaking through the seasonal limitations of the four-fingered mackerel's reproduction and achieving year-round natural spawning.

[0004] To achieve the above objectives, the present invention adopts the following technical solution.

[0005] A method for artificially controlling the natural spawning of four-fingered mackerel parent fish throughout the year includes the following steps:

[0006] (1) Batch spawning management of broodstock:

[0007] The mature broodstock were divided into two groups, A and B, and raised in different broodstock ponds for alternating spawning and egg production.

[0008] Group A's ovulation induction and spawning time: June to August and December to February.

[0009] Group B's induced labor and spawning time: March to May and September to November;

[0010] Among them, hot water pipes are laid at the bottom of the parent fish pond in Group A to heat the pond water in winter;

[0011] (2) Complex environmental regulation during the spawning period:

[0012] Water flow stimulation: 48 hours before spawning, start a 4-inch submersible pump to draw in the reserve culture seawater and flush it into the parent fish pond to create a water flow impact on the parent fish in the pond. The water flow speed is 2.4 m / s. When the fish are observed to be chasing each other to spawn, stop flushing.

[0013] Salinity control: The salinity of the broodstock pond water is controlled within the range of 26-30‰ throughout the year;

[0014] Precise temperature control: During the spawning period, the water temperature in the broodstock pond is controlled between 26 and 31°C to ensure the spawning temperature. Furthermore, during periods of low temperature, the following measures are taken to maintain a suitable spawning temperature:

[0015] In winter, double-layered inflatable membrane structures were used to build insulation sheds for the Group A broodstock ponds. The construction was completed between October and early November to improve insulation performance and save energy, providing sufficient temperature for the Group A broodstock to spawn in winter.

[0016] b. When the water temperature in the parent fish pond of Group A is below 26℃ during the spawning period, hot water is supplied to the bottom hot water pipe to raise the water temperature to above 26℃.

[0017] (3) Stage-specific nutritional fortification during the spawning period:

[0018] From 30 days before spawning until the start of the spawning period, in addition to feeding high-protein pelleted feed, fish oil, egg yolk protein, shrimp, oysters, and squid are supplemented as nutritional fortifiers, and vitamin E and vitamin C are added. The amount of fish oil, egg yolk protein, vitamin E, and vitamin C fed is 2-3% of the weight of high-protein pelleted feed, and the amount of shrimp, oysters, and squid fed is 0.3% of the weight of the broodstock, to promote the development of oocytes and yolk formation in the gonads of the broodstock; the crude protein content of the high-protein pelleted feed is ≥45%;

[0019] Furthermore, for Group A broodstock that spawn in winter, normal feeding is provided during the overwintering period. Thirty days before spawning, Antarctic krill powder and Schizochytrium powder are added to enhance the nutrition, immunity, and digestion of the spawning broodstock. The feeding amounts of Antarctic krill powder and Schizochytrium powder are 3% and 1.2% of the high-protein pelleted feed, respectively. During the winter spawning period, Group A broodstock are supplemented with compound vitamins on top of the high-protein pelleted feed. The compound vitamins are 2% of the high-protein pelleted feed and contain 800 IU / kg vitamin E and 5‰ vitamin C.

[0020] (4) Postpartum recovery of parent fish:

[0021] During the alternating spawning period of parent fish in groups A and B, the parent fish that have finished induced spawning and spawning enter the postpartum recovery phase, which lasts for one month. During the postpartum recovery phase, compound vitamins are fed in combination with high-protein pelleted feed to accumulate nutrients and energy for the next stage of spawning and to promote good gonadal development, thus preparing for the production of high-quality male and female gametes. The compound vitamins are fed at 2% of the mass of the high-protein pelleted feed, which includes 800 IU / kg of vitamin E and 5‰ of vitamin C.

[0022] This invention employs a comprehensive management approach, incorporating environmental, biological, nutritional, and broodstock management methods, to regulate the gonadal development of broodstock of the four-fingered mackerel, achieving year-round natural spawning. It also addresses the deficiency in patent CN113812356A, where broodstock produce no fertilized eggs from mid-November to mid-March. This invention utilizes a batch-based spawning management method, allowing the broodstock sufficient time to recover post-spawning and replenish nutrients for gonadal development. This results in a continuous production of more uniform and higher-quality gametes, leading to higher spawning yields, better fertilization rates, hatching rates, and post-spawning survival rates. Furthermore, unlike patent CN113812356A, which uses a water flow of 0.4–0.6 m / s to promote gradual gonadal development during pre-spawning rearing, this invention uses a higher water flow of 2.4 m / s to stimulate spawning. Once the spawning cycle begins, the water flow is stopped, which promotes concentrated spawning, resulting in a larger and more uniform egg production and improved spawning efficiency.

[0023] Preferably, 300 to 400 broodstock are stocked in each broodstock pond of 2 to 3 mu (approximately 0.33 to 0.33 hectares), with the ratio of male to female broodstock in the pond being 1:1 to 1:2.

[0024] Preferably, the broodstock of Group B are in the postpartum recovery stage when they overwinter, that is, they are fed with the above-mentioned recovery period compound vitamins combined with high-protein pellet feed, and ordinary overwintering sheds are built for the broodstock ponds of Group B.

[0025] Furthermore, this invention also includes the use of probiotics to synergistically regulate water quality; specifically, the following methods are used alternately every 10 days to regulate the water quality in the broodstock pond, degrade and transform metabolic products, and prevent cyanobacterial proliferation and algal blooms: a. Using a 3:1 mass ratio of Bacillus subtilis and Lactobacillus plantarum, sprinkled throughout the pond; b. Using Clostridium butyricum combined with beneficial bacteria such as Bacillus subtilis, lactic acid bacteria, and yeast, sprinkled on the water surface once a day for 3 consecutive days; c. Using 100-250g of cyanobacterium-dissolving bacteria per acre, sprinkled throughout the pond. This invention achieves a better synergistic regulatory effect by using the above three methods in combination at different times and spaces to regulate water quality.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] This invention breaks through the seasonal limitation of the short breeding season of the four-fingered mackerel, enabling natural spawning throughout the year. It also solves the industry problem of low overwintering survival rate, and improves the spawning volume, fertilization rate, hatching rate and post-spawning survival rate of broodstock. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments.

[0029] Example 1

[0030] Follow these steps to artificially regulate the natural spawning of parent fish throughout the year:

[0031] 1. Preparation of broodstock ponds and batch spawning management of broodstock

[0032] The mature parent fish were divided into two groups, A and B, and spawning was induced and spawning was carried out alternately.

[0033] Group A's ovulation induction and spawning time: June to August, December to February.

[0034] Group B's induced labor and spawning time: March to May, September to November;

[0035] Two groups of parent fish, A and B, were raised in separate parent fish ponds for cultivation.

[0036] The broodstock ponds cover an area of ​​2-3 mu (approximately 0.33-0.2 hectares) with a water depth of 1.5-1.8 meters. Each diagonal corner of the broodstock pond is equipped with a waterwheel-type aerator (2.0kW / unit) and an egg collection device to control dissolved oxygen at 5.1-7.6 mg / L. The dissolved oxygen rate in the ponds is monitored through an environmental monitoring system. Each broodstock pond is equipped with an automatic feeder. Adjacent to the broodstock ponds is a water storage tank containing seawater with the same salinity as the broodstock ponds.

[0037] Group A broodstock ponds are equipped with hot water pipes at the bottom and a boiler room on land, which contains a boiler heating device. The boiler and hot water pipes form a closed-loop water heating system that can heat the pond water in winter. Group B broodstock ponds are not equipped with a boiler heating system.

[0038] Each parent fish pond is stocked with 300 to 400 parent fish, with male and female parent fish mixed together in a ratio of 1:1 to 1:2.

[0039] 7-15 days before introducing the parent fish into the pond, the pond should be cleaned, exposed to the sun, and dry-sprinkled with quicklime. Then, fertilizer and compound microbial agents should be added to adjust the water transparency and salinity and fertilize the water.

[0040] Select mature four-finger mackerel broodstock that are plump and have a slightly or obviously swollen abdomen, and carefully transfer them to the broodstock pond for cultivation.

[0041] 2. Complex environmental regulation during the spawning period

[0042] Water flow stimulation: 48 hours before spawning, use a 4-inch submersible pump to draw seawater of the same salinity from the reservoir and flush it into the parent fish pond to create a water flow impact on the parent fish in the pond. The water flow speed is 2.4 m / s. When the fish are observed to be chasing each other to spawn, stop flushing.

[0043] Salinity control: The salinity of the parent fish pond water is controlled within the range of 26-30‰ throughout the year. High-salinity seawater or freshwater used for salinity adjustment must be sedimented and filtered to ensure that the water is fresh, clean, unpolluted, and free of pathogens.

[0044] Precise temperature control: During the spawning period, the water temperature in the broodstock pond is controlled between 26 and 31°C, and the following measures are taken to maintain a suitable spawning temperature during the low-temperature spawning period:

[0045] a. In winter, double-layered inflatable membrane structures are used to build heat-insulating sheds for the Group A broodstock ponds. The structures are completed between October and early November to improve heat preservation performance and save energy, providing sufficient temperature for the broodstock to spawn in winter.

[0046] b. When the water temperature is below 26℃, start the circulating water heating system to allow hot water to flow into the hot water pipes at the bottom of the A group of parent fish ponds, raising the pond water temperature to above 26℃.

[0047] 3. Use probiotics to synergistically regulate water quality

[0048] a. Use Bacillus subtilis and Lactobacillus plantarum in a 3:1 mass ratio and sprinkle the mixture throughout the pond; b. Sprinkle 50g of Butyric Acid Intestinal Detox and 0.5kg of Active Enzyme (both products contain beneficial bacteria such as Clostridium butyricum, Bacillus subtilis, Lactobacillus, and yeast) per acre of pond surface once a day for 3 consecutive days, then stop until method a or c is used; c. Use 100-250g of Blue-green Algae Dissolving Bacterium per acre and sprinkle it throughout the pond. Throughout the broodstock rearing process, use all three methods once a month, alternating between methods every 10 days to synergistically regulate water quality, degrade and transform metabolic products, and prevent blue-green algae proliferation and algal blooms.

[0049] 4. Stage-specific nutritional fortification during the spawning period

[0050] In daily management, use complete artificial compound floating pellet feed (hereinafter referred to as high protein pellet feed) produced by regular feed manufacturers, with a crude protein content of more than 45%, and feed once in the morning and once in the afternoon, with a daily feeding amount of 3 to 5% of the fish's body weight.

[0051] From 30 days before spawning until the start of the spawning period, in addition to the above-mentioned high-protein pelleted feed, fish oil, egg yolk protein, shrimp, oysters, and squid are supplemented as nutritional fortifiers. Vitamin E and vitamin C are also appropriately increased, with fish oil, egg yolk protein, vitamin E, and vitamin C accounting for 2-3% of the weight of the high-protein pelleted feed, and shrimp, oysters, and squid accounting for 0.3% of the broodstock's body weight. This promotes the development of oocytes and yolk formation in the broodstock's gonads. High-protein pelleted feed is used during the spawning period.

[0052] For Group A broodstock that are planned to spawn in winter, they are fed normally during the overwintering period. In the 30 days before spawning, in addition to the aforementioned nutritional fortification methods, they are also fed Antarctic krill powder and Schizochytrium powder to help the spawning broodstock enhance nutrition, improve immunity, and promote digestion. The feeding amounts of Antarctic krill powder and Schizochytrium powder are 3% and 1.2% of the mass of high-protein pelleted feed, respectively (see Table 1).

[0053] During the winter spawning period, Group A broodstock were fed a compound vitamin supplement on top of a high-protein pelleted feed. The compound vitamin was added at 2% of the mass of the high-protein pelleted feed, and it contained 800 IU / kg of vitamin E and 5‰ of vitamin C (see Table 1).

[0054] Table 1

[0055]

[0056] 5. Postpartum recovery of parent fish

[0057] During the alternating spawning period of the parent fish in groups A and B, the parent fish that have finished induced spawning and spawning enter the postpartum recovery stage, which lasts for 1 month.

[0058] During the postpartum recovery phase, maintaining good water quality and nutrition is crucial to promote the healthy recovery of broodstock. Feeding with high-protein pelleted feed plus 2% compound vitamins (containing 800 IU / kg of vitamin E and 5‰ of vitamin C) helps accumulate nutrients and energy for the next stage of spawning and promotes healthy gonadal development, preparing for the production of high-quality male and female gametes.

[0059] For the overwintering period of Group B broodstock, this period is the postpartum recovery stage. The above-mentioned method of feeding compound vitamins combined with high-protein pelleted feed is adopted. After the recovery period, feeding is carried out according to the conventional overwintering management until the next nutritional fortification begins. Ordinary overwintering sheds are built for the Group B broodstock ponds for overwintering.

[0060] This embodiment describes an artificial method for controlling the year-round spawning of four-fingered mackerel broodstock. Approximately 2000 broodstock are involved, with a total annual spawning volume of about 330 million eggs. This represents an increase of approximately 28% compared to the year-round spawning volume of Chinese Patent CN113812356A, and an increase of 82% compared to existing general techniques. The average fertilization rate of this embodiment is approximately 90%, and the average hatching rate is approximately 85%, both representing an increase of approximately 10% compared to Chinese Patent CN113812356A and an increase of 30% compared to existing general techniques. The post-spawning survival rate of the broodstock in this embodiment is approximately 98%, an increase of approximately 5% compared to Chinese Patent CN113812356A and an increase of 15% compared to existing general techniques.

Claims

1. A method for artificially controlling the year-round natural spawning of broodstock of the four-fingered mackerel, characterized in that, Includes the following steps: (1) Batch spawning management of broodstock: The mature broodstock were divided into two groups, A and B, and raised in different broodstock ponds for alternating spawning and egg production. Group A's induced labor and spawning time: June to August and December to February. Group B's induced labor and spawning time: March to May and September to November; Among them, hot water pipes are laid at the bottom of the parent fish pond in Group A to heat the pond water in winter; (2) Complex environmental regulation during the spawning period: Water flow stimulation: 48 hours before spawning, start a 4-inch submersible pump to draw in the reserve culture seawater and flush it into the parent fish pond to create a water flow impact on the parent fish in the pond. The water flow speed is 2.4 m / s. When the fish are observed to be chasing each other to spawn, stop flushing. Salinity control: The salinity of the broodstock pond water is controlled within the range of 26-30‰ throughout the year; Precise temperature control: During the spawning period, the water temperature in the broodstock pond is controlled at 26~31℃ to ensure the spawning temperature. During periods of low temperature, the following measures are taken to maintain a suitable spawning temperature: a. In winter, double-layered inflatable membrane structures were used to build heat-insulating sheds for the Group A broodstock ponds. The structures were completed between October and early November to improve heat preservation performance and save energy, providing sufficient temperature for the Group A broodstock to spawn in winter. b. When the water temperature in the parent fish pond of Group A is below 26℃ during the spawning period, hot water is supplied to the bottom hot water pipe to raise the water temperature to above 26℃. (3) Stage-based nutritional fortification during the spawning period: From 30 days before spawning until the start of the spawning period, in addition to feeding high-protein pelleted feed, fish oil, egg yolk protein, shrimp, oysters and squid are added as nutritional fortifiers, and vitamin E and vitamin C are also added. Furthermore, for Group A broodstock that spawn in winter, they are fed normally during the overwintering period, and supplemented with Antarctic krill powder and Schizochytrium powder 30 days before spawning; during the winter spawning period, Group A broodstock are fed compound vitamins in addition to high-protein pelleted feed. (4) Postpartum recovery of parent fish: During the alternating spawning period of the parent fish in groups A and B, the parent fish that have finished induced spawning and spawning enter the postpartum recovery stage, which lasts for 1 month. During the postpartum recovery stage, they are fed with compound vitamins in combination with high-protein pelleted feed. The compound vitamins contain 800 IU / kg of vitamin E and 5‰ of vitamin C.

2. The method for artificially controlling the year-round natural spawning of four-fingered mackerel broodstock as described in claim 1, characterized in that, It also includes using probiotics to synergistically regulate water quality; specifically, one of the following methods is used alternately every 10 days to regulate the water quality in the broodstock pond: a. Use a compound of Bacillus and Lactobacillus plantarum, sprinkled throughout the pond; b. Use Clostridium butyricum combined with Bacillus, lactic acid bacteria and yeast to sprinkle on the water surface once a day for 3 consecutive days; c. Use cyanobacteria-dissolving bacteria, sprinkled throughout the pond.

3. The method for artificially controlling the year-round natural spawning of four-fingered mackerel broodstock as described in claim 2, characterized in that, Each broodstock pond, measuring 2 to 3 acres, is stocked with 300 to 400 broodstock fish, with a male-to-female ratio of 1:1 to 1:

2.

4. The method for artificially controlling the year-round natural spawning of four-fingered mackerel broodstock as described in claim 3, characterized in that, When the broodstock of Group B were overwintering, they were in the postpartum recovery stage. They were fed with the above-mentioned recovery period compound vitamins combined with high-protein pellet feed, and ordinary overwintering sheds were built for the Group B broodstock ponds.

5. The artificial regulation method for year-round natural spawning of four-fingered mackerel broodstock as described in claim 4, characterized in that, In step (3), the amount of fish oil, egg yolk protein, vitamin E and vitamin C fed is 2 to 3% of the weight of high-protein pellet feed, and the amount of shrimp, oyster and squid fed is 0.3% of the weight of the parent fish.

6. The method for artificially controlling the year-round natural spawning of four-fingered mackerel broodstock as described in claim 5, characterized in that, In step (3), the feeding amounts of Antarctic krill powder and Schizochytrium powder are 3% and 1.2% of the mass of the high-protein pellet feed, respectively.

7. The method for artificially controlling the year-round natural spawning of four-fingered mackerel broodstock as described in claim 6, characterized in that, In steps (3) and (4), the amount of the compound vitamins fed is 2% of the mass of the high-protein pellet feed.

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