Ecological breeding system and method for macrobrachium rosenbergii in land-based circular pond

Abstract

This invention discloses a land-based circular pond ecological seedling cultivation system and method for giant freshwater prawns, belonging to the field of seedling cultivation technology. It includes steps such as stocking, water quality management, feeding management, pond transfer, and larval desalination. The system maintains a microalgae abundance of 10⁴-10⁷ cells / mL through microecological regulation, adds beneficial microecological agents, and purifies the water using a microfiltration machine, disinfection tank, and water purification tank. Feeding management is adjusted according to the larval growth stages: no feeding in stage I, mainly Artemia nauplii in stages II-VI, gradually increasing shrimp flakes in stages VII-XI, and feeding egg custard and shrimp flakes during the larval stage. Pond transfer is carried out when ammonia nitrogen ≥2 mg / L or nitrite ≥0.5 mg / L. Larval desalination is achieved by adding fresh water daily to reduce salinity to 3‰. This invention is suitable for large-scale seedling cultivation, significantly improving larval survival rate and growth rate, and is characterized by high efficiency and ecological sustainability. It can be widely applied to other aquaculture fields.

Description

Technical Field

[0001] This invention relates to the field of seedling technology, and in particular to a land-based circular pond ecological seedling system and method for giant freshwater prawns. Background Technology

[0002] The giant freshwater prawn (Macrobrachium rosenbergii) belongs to the class Crustacea, order Decapoda, family Palaemonidae, and genus Macrobrachium. It is one of the largest freshwater shrimp in the world. According to surveys, current giant freshwater prawn hatcheries primarily use traditional cement ponds for raising larvae.

[0003] The traditional cement pond shrimp larvae rearing model has remained relatively fixed and simple after decades of development. While it has advantages such as low cost, simple and basic operation, and low technical requirements, it also has many drawbacks. These include the need for significant manpower, material resources, and financial investment in larvae rearing and management; difficulty in controlling water quality; challenges in establishing standardized management models; and frequent disease outbreaks. This results in highly unstable production quantities and quality of giant freshwater prawn larvae, with survival rates sometimes reaching 90% and sometimes falling below 10%. Furthermore, poor larvae quality often necessitates draining the entire pond, causing substantial economic losses. This traditional cement pond rearing model significantly impacts and restricts the high-quality development of the giant freshwater prawn industry, failing to meet the current demand from farmers for large quantities of high-quality larvae. Summary of the Invention

[0004] To address the shortcomings of the existing technologies, this invention provides a land-based circular pond ecological seedling raising system and method for giant freshwater prawns. Through a series of operational procedures, including reasonable stocking, water quality management, feeding management, pond transfer, and freshwater acclimation of prawn seedlings, combined with specific micro-ecological regulation, water purification measures, and aquaculture equipment, the survival rate and quality of giant freshwater prawn seedlings are improved, achieving sustainable seedling production.

[0005] The specific technical solution is as follows: In a first aspect, this invention discloses a method for ecological breeding of giant freshwater prawns in a land-based circular pond, comprising: Release the seedlings in the morning. The newly released larvae, at a density of 1 million to 1.2 million per tank, are zoea larvae of stages I to VI. After being raised in cement ponds, they are then transferred to the rearing tanks. Water quality management: Initially, the water volume in the larval rearing tank is 2-3 m³, gradually increasing to 5 m³; adjust the salinity to 12-14‰, maintain dissolved oxygen ≥5 mg / L and water temperature 30-32℃; maintain the water quality at the following levels through micro-ecological regulation, siphon suction, direct discharge, and water purification: ammonia nitrogen ≤2 mg / L, nitrite ≤0.5 mg / L, and pH 7.5-8.5. Feeding management: During the zoea larval stage, stage I larvae are not fed; stage II-VI larvae are mainly fed Artemia nauplii; stage VII-XI larvae are mainly fed egg custard with shrimp chips gradually added; stage XI larvae are kept with sufficient Artemia nauplii; during the juvenile shrimp stage, egg custard and shrimp chips are fed according to the set time. Transfer the seedlings to a new culture tank every 6-7 days during the culture cycle. When ammonia nitrogen ≥2mg / L, nitrite ≥0.5mg / L and the fleas are eating less, use a 40-mesh or 20-mesh net to collect the seedlings and transfer them to a new culture tank. Transfer the seedlings to a new culture tank 0-3 times depending on the water quality. After the shrimp larvae have been acclimated to freshwater, and more than 90% of their bodies have metamorphosed into juvenile shrimp, freshwater is added daily for 2-3 days to reduce the salinity by 1-3‰ each day until it reaches 3‰, at which point they are ready to be harvested or sold.

[0006] Furthermore, the microecological regulation in the above scheme involves adding 50-100L of microalgae solution and 3-5g / m³ of beneficial microecological agents daily after the water quality regulation is satisfactory, so that the abundance of microalgae in the water body is maintained at 104-107 cells / mL. The microalgae solution includes Chlorella, Cyclophyta, Platycodon, Chaetoceros, and Spirulina, and the beneficial microecological agents include photosynthetic bacteria, lactobacilli, and Bacillus.

[0007] Furthermore, after the zoea larvae grow to stage VI, the wastewater in the tank is discharged sequentially from the primary sewage pipe to the microfilter, microalgae treatment tank, disinfection tank and water purification tank, and then the filtered water is discharged into the aquaculture tank. Before the microfilter is turned on, the gas is stopped for 5-15 minutes to allow a large amount of particulate matter to settle to the bottom, 1-2 times a day, 30-120 minutes each time.

[0008] Furthermore, in the above scheme, the salinity of the water used for microalgae culture is 12-14%, dissolved oxygen is ≥5mg / L, and the water temperature is 30-32℃, with culture medium added for cultivation.

[0009] Furthermore, in the above scheme, after the flea larvae grow to stage VI, the wastewater and large particulate matter that cannot be filtered by the microfilter are discharged into the sedimentation tank through the sewage pipe.

[0010] Furthermore, the above plan specifies the following feeding times per day: egg custard with shrimp chips: 6:00, 10:00, 12:00, 16:00, and 19:00; and the feeding times for Artemia nauplii: 8:00-9:00 and 14:00-15:00.

[0011] Furthermore, in the above scheme, the microfilter is connected to the breeding tank through a secondary sewage pipe. When the zoea larvae grow to stage VI, the sewage in the breeding tank is directly discharged from the secondary sewage pipe to the microfilter, and then the filtered water is discharged into the breeding tank.

[0012] Furthermore, the primary sewage pipe is divided into multiple sewage channels along its length, and the sewage channels are respectively connected to the sewage inlets at the bottom and side walls of the primary sewage pipe.

[0013] Furthermore, the bottom of the aquaculture tank is conical, and a nano-aeration pipe is laid at the bottom of the aquaculture tank. A water inlet pipe is vertically installed on the side wall of the aquaculture tank, and water outlet holes are evenly distributed along the length of the water inlet pipe. The water outlet holes are horizontal and inclined relative to the axis of the aquaculture tank. A heating pipe for heating the water is laid inside the aquaculture tank.

[0014] Secondly, this invention also discloses a system for the land-based circular pond ecological seedling cultivation method of giant freshwater prawns, comprising: Culture tanks are used for the rearing of giant freshwater prawn larvae. The water purification unit includes a microfilter, a microalgae treatment tank, a disinfection tank, and a purified water tank connected in sequence. The microalgae cultivation unit is used for cultivating microalgae, which is then introduced into the cultivation tanks through a mixing pipeline. Sedimentation tanks are used to settle and filter wastewater discharged from water purification units.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention, by rationally controlling stocking density, providing suitable feed according to different growth stages of zoea larvae, and precisely setting feeding times, fully meets the nutritional needs of larval growth. These measures effectively improve the survival rate of shrimp larvae, increasing it by approximately 20% compared to traditional methods. Furthermore, the cultivated shrimp larvae are robust and grow at a uniform rate, laying a solid foundation for subsequent aquaculture production.

[0016] This invention comprehensively utilizes measures such as microecological regulation, siphon suction, direct sewage discharge, and water purification. Daily addition of microalgae solution and beneficial microecological agents maintains the abundance of microalgae in the water and effectively improves the water quality and degrades harmful substances through the ecological functions of microalgae and beneficial microorganisms. Simultaneously, a purification system composed of a microfilter, ozone sterilizer, and purifier regularly purifies the aquaculture water, ensuring that the water quality remains at an optimal level with ammonia nitrogen ≤2mg / L, nitrite ≤0.5mg / L, and pH 7.5-8.5, saving 30-40% of water. This significantly reduces the occurrence of diseases, lowers shrimp larvae losses due to water quality issues, and consequently reduces aquaculture costs.

[0017] This invention exhibits strong adaptability to aquaculture environments. By rationally adjusting water quality parameters such as temperature and salinity, a stable environment suitable for the growth of giant freshwater prawn larvae is created, providing a strong guarantee for sustainable seedling production. In practical applications, this method demonstrates good feasibility and effectiveness, providing an efficient and ecological solution for the development of the giant freshwater prawn seedling industry. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the method steps of the present invention; Figure 2 This is a functional framework diagram of the system of the present invention. Detailed Implementation

[0019] The embodiments of the invention will be described in further detail below with reference to the accompanying drawings, so that the objectives, technical solutions and technical effects of the invention will be more clearly presented.

[0020] like Figure 1 As shown, this invention discloses a method for ecological breeding of giant freshwater prawns in a land-based circular pond, comprising: Release of seedlings: In the morning, the newly released larvae, at a density of 1-1.2 million per tank, are raised in cement ponds for stages I to VI zoea larvae before being transferred to the rearing tanks.

[0021] Water quality management: The initial water volume in the larval rearing tank is 2-3 m³, which is gradually increased to 5 m³. The salinity is adjusted to 12-14‰, and the dissolved oxygen is maintained at ≥5 mg / L and the water temperature is 30-32℃. Through microecological regulation, siphon suction, direct discharge and water purification, the water quality is maintained at: ammonia nitrogen ≤2 mg / L, nitrite ≤0.5 mg / L and pH value 7.5-8.5.

[0022] Feeding Management: During the zoea larval stage, stage I larvae are not fed. Stages II-VI larvae are mainly fed Artemia nauplii. Stages VII-XI are mainly fed egg custard with the gradual addition of shrimp chips. Stage XI is fed a sufficient supply of Artemia nauplii. During the juvenile shrimp stage, feed egg custard and shrimp chips according to the set feeding times. Daily feeding times for egg custard and shrimp chips: 6:00, 10:00, 12:00, 16:00, and 19:00. Daily feeding times for Artemia nauplii: 8:00-9:00 and 14:00-15:00.

[0023] Pond transfer: Every 6-7 days of the breeding cycle, when ammonia nitrogen ≥2mg / L, nitrite ≥0.5mg / L and the fleas' feeding decreases, use a 40-mesh or 20-mesh net to collect the seedlings and transfer them to a new breeding tank. Transfer the seedlings 0-3 times depending on the water quality.

[0024] Freshwater acclimatization of shrimp larvae: After more than 90% of the larvae have metamorphosed into juvenile shrimp, add fresh water daily for 2-3 days to reduce the salinity by 1-3‰ each day until the salinity reaches 3‰, at which point the shrimp can be harvested or sold.

[0025] In the above-mentioned scheme, in order to maintain the abundance of microalgae and the balance of beneficial microorganisms in the water, the microecological regulation involves adding 50-100L of microalgae solution and 3-5g / m³ of beneficial microecological agents daily after the water quality regulation is met, so as to maintain the abundance of microalgae in the water at 10. 4 -10 7The cell / mL microalgae solution contains Chlorella, Cyclostome, Platycodon, Chaetoceros, and Spirulina, among others, and beneficial microecological agents include photosynthetic bacteria, lactobacilli, and Bacillus.

[0026] To effectively treat wastewater and particulate matter in the aquaculture tanks, after the zoea larvae reach stage VI, the wastewater is sequentially discharged from the primary drain pipe to a microfilter, disinfection tank, and purification tank, before the filtered water is returned to the aquaculture tanks. Before turning on the microfilter, aeration is stopped for 5-15 minutes to allow a large amount of particulate matter to settle, 1-2 times daily for 30-120 minutes each time. This ensures that the wastewater is filtered, disinfected, and purified before returning to the aquaculture tanks, maintaining clean and stable water quality. Once the zoea larvae reach stage VI, the microfilter is connected to the aquaculture tanks via a secondary drain pipe, from which wastewater is directly discharged to the microfilter, before the filtered water is returned to the aquaculture tanks. To improve the coverage and efficiency of the drainage system, the primary drain pipe is divided into multiple drainage channels along its length. These channels are connected to the inlets at the bottom and side walls of the primary drain pipe, allowing wastewater to be quickly discharged through multiple channels, reducing dead zones and improving drainage efficiency.

[0027] To provide suitable environmental conditions for microalgae cultivation, the water salinity during microalgae culture was set at 12-14%, dissolved oxygen ≥5 mg / L, and water temperature at 30-32℃, with the addition of culture medium. This ensures that the microalgae can grow in the optimal environment, guaranteeing the quality and quantity of the microalgae culture solution.

[0028] Here, the bottom of the culture tank is conical, and nano-aeration pipes are laid at the bottom. A water inlet pipe is vertically installed on the side wall of the culture tank, and a water outlet is located at the bottom. A 60cm diameter mesh cover with 60mm apertures is placed above the water outlet to prevent shrimp larvae from being trapped. Heating pipes for water heating are installed inside the culture tank. The culture tank allows for even water distribution and circulation, maintaining stable water temperature and quality, and promoting the healthy growth of shrimp larvae.

[0029] The following are detailed instructions with reference to the specific operating steps: First, stocking is carried out by placing 1-1.2 million zoea larvae (stages I to VI) into each rearing tank. For water quality management, the initial water volume is 2-3 m³, gradually increasing to 5 m³. Salinity is adjusted to 12-14‰, dissolved oxygen is maintained at ≥5 mg / L, and water temperature is 30-32℃. Through microecological regulation, siphon suction, direct wastewater discharge, and water purification, the water quality is controlled within the range of ammonia nitrogen ≤2 mg / L, nitrite ≤0.5 mg / L, and pH 7.5-8.5. Feeding management is conducted according to the different growth stages of shrimp larvae. Stage I larvae are not fed; stages II-VI are mainly fed Artemia nauplii; stages VII-XI gradually increase shrimp flakes; and the juvenile stage is mainly fed egg custard and shrimp flakes. Feeding times are fixed at 6:00, 10:00, 12:00, 16:00, and 19:00 daily. Artemia nauplii are fed from 8:00-9:00 and 14:00-15:00. Transferring larvae to new ponds is carried out when ammonia nitrogen or nitrite levels are high and shrimp larvae feed intake decreases. Every 6-7 days, shrimp larvae are transferred to new ponds using a net. The number of transfers depends on water quality conditions and is 0-3 times. During the acclimation stage, after more than 90% of the larvae have metamorphosed into juveniles, fresh water is added daily to reduce salinity by 1-3‰ until the salinity reaches 3‰, at which point the larvae are ready for harvesting or sale.

[0030] Microecological regulation is achieved by adding 50-100L of microalgae solution and 3-5g / m³ of beneficial microecological agents daily to maintain the microalgae abundance in the water at 10⁴-10⁷ cells / mL. The microalgae species include Chlorella, Cyclophyllum, Platycladus, Chaetoceros, and Spirulina. Beneficial microecological agents include photosynthetic bacteria, lactobacilli, and Bacillus. The wastewater system uses a primary drain pipe to sequentially discharge wastewater into a microfiltration unit, microalgae treatment tank, disinfection tank, and purification tank. The filtered water is then returned to the culture tank. Before starting the microfiltration unit, aeration is stopped for 5-15 minutes to allow particulate matter to settle. The system operates 1-2 times daily for 30-120 minutes each time. During microalgae culture, the water salinity is maintained at 12-14%, dissolved oxygen ≥5mg / L, and water temperature at 30-32℃, with culture medium added. Wastewater and large particles that cannot be filtered by the microfiltration unit are discharged into a sedimentation tank through a drain pipe. The bottom of the aquaculture tank is conical, with nano-aeration pipes laid on it. The side wall has a water inlet pipe, and the water outlet is horizontal and inclined. The tank is also equipped with a heating pipe to maintain the water temperature.

[0031] like Figure 2 As shown, on the other hand, this invention discloses a system for a land-based circular pond ecological seedling cultivation method for giant freshwater prawns, comprising: A culture tank used for the rearing of giant freshwater prawn larvae.

[0032] The water purification unit includes a microfilter, a microalgae treatment unit, a disinfection tank, and a purification tank connected in sequence.

[0033] The microalgae cultivation unit is used for cultivating microalgae, which is then introduced into the culture tanks through a mixing pipeline.

[0034] In the water purification unit: the microfilter is located at the front end of the water purification process. It performs preliminary filtration of the aquaculture water, removing larger particles of impurities, uneaten feed, feces, etc., reducing the load on subsequent treatment units and ensuring that the water entering the subsequent treatment stages is relatively clean.

[0035] The microalgae treatment unit, building upon the microfiltration process, further purifies the water by utilizing the physiological characteristics of microalgae. Microalgae can absorb nutrients such as nitrogen and phosphorus from the water, reducing eutrophication, and simultaneously release oxygen through photosynthesis, increasing dissolved oxygen levels and improving the aquatic environment.

[0036] The disinfection and purification device disinfects the water after it passes through the microalgae treatment unit, killing harmful microorganisms, bacteria, viruses, etc. in the water, ensuring that the water entering the breeding tank is safe and hygienic, and reducing the risk of disease in larvae.

[0037] Microalgae cultivation unit: This unit is specifically designed for cultivating microalgae. The cultivated microalgae can serve as a high-quality natural food for giant freshwater prawn larvae, providing them with abundant nutrients. Additionally, they can be introduced into the culture tanks through distribution pipes to participate in the ecological balance regulation of the culture water, helping to maintain a good water quality environment.

[0038] Sedimentation tank: Receives wastewater discharged from the water purification unit. Through sedimentation and filtration, suspended particles and colloidal substances in the wastewater settle, further removing impurities and achieving preliminary purification and recycling of water resources. The supernatant after sedimentation can be re-entered into the water purification unit for further treatment as needed, while the settled sludge and other substances can be properly treated and disposed of.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the patent application of the present invention. All equivalent changes, substitutions or modifications made within the technical spirit and principles indicated by the present invention should be included within the scope of patent protection covered by the present invention.

Claims

1. A method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond, characterized in that, include: Release the seedlings in the morning. The newly released larvae, at a density of 1 million to 1.2 million per tank, are zoea larvae of stages I to VI. After being raised in cement ponds, they are then transferred to the rearing tanks. Water quality management: Initially, the water volume in the larval rearing tank is 2-3 m³, gradually increasing to 5 m³; adjust the salinity to 12-14‰, maintain dissolved oxygen ≥5 mg / L and water temperature 30-32℃; maintain the water quality at the following levels through micro-ecological regulation, siphon suction, direct discharge, and water purification: ammonia nitrogen ≤2 mg / L, nitrite ≤0.5 mg / L, and pH 7.5-8.

5. Feeding management: During the zoea larval stage, stage I larvae are not fed; stage II-VI larvae are mainly fed Artemia nauplii; stage VII-XI larvae are mainly fed egg custard with shrimp chips gradually added; stage XI larvae are kept with sufficient Artemia nauplii; during the juvenile shrimp stage, egg custard and shrimp chips are fed according to the set time. Transfer the seedlings to a new culture tank every 6-7 days during the culture cycle. When ammonia nitrogen ≥2mg / L, nitrite ≥0.5mg / L and the fleas are eating less, use a 40-mesh or 20-mesh net to collect the seedlings and transfer them to a new culture tank. Transfer the seedlings to a new culture tank 0-3 times depending on the water quality. After the shrimp larvae have been acclimated to freshwater, and more than 90% of their bodies have metamorphosed into juvenile shrimp, freshwater is added daily for 2-3 days to reduce the salinity by 1-3‰ each day until it reaches 3‰, at which point they are ready to be harvested or sold.

2. The method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond according to claim 1, characterized in that: The microecological regulation involves adding 50-100L of microalgae solution and 3-5g / m³ of beneficial microecological agents daily after the water quality meets the standards, so as to maintain the microalgae abundance in the water body at 10. 4 -10 7 The cell / mL microalgae solution contains Chlorella, Cyclostome, Platycodon, Chaetoceros, and Spirulina, and the beneficial microecological preparations include photosynthetic bacteria, lactobacilli, and Bacillus.

3. The method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond according to claim 1, characterized in that: After the zoea larvae grow to stage VI, the wastewater in the tank is discharged sequentially from the primary sewage pipe to the microfilter, microalgae treatment tank, disinfection tank and water purification tank, and then the filtered water is discharged into the culture tank. Before turning on the microfilter, the gas is stopped for 5-15 minutes to allow a large amount of particulate matter to settle to the bottom. This is done 1-2 times a day, for 30-120 minutes each time.

4. The method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond according to claim 3, characterized in that: The microalgae were cultured in a water with a salinity of 12-14%, dissolved oxygen ≥5 mg / L, and a water temperature of 30-32℃, with culture medium added for cultivation.

5. The method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond according to claim 1, characterized in that: After the flea larvae grow to stage VI, the wastewater and large particles that cannot be filtered by the microfilter are discharged into the sedimentation tank through the drain pipe.

6. The method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond according to claim 1, characterized in that: Feeding times for egg custard and shrimp chips: 6:00, 10:00, 12:00, 16:00, and 19:00 daily; feeding times for Artemia nauplii: 8:00-9:00 and 14:00-15:00 daily.

7. The method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond according to claim 3, characterized in that: The microfilter is connected to the breeding tank through a secondary sewage pipe. When the zoea larvae grow to stage VI, the sewage in the breeding tank is directly discharged into the microfilter through the secondary sewage pipe, and then the filtered water is discharged into the breeding tank.

8. The method for ecological seedling raising of giant freshwater prawns in a land-based circular pond according to claim 3, characterized in that: The primary sewage pipe is divided into multiple sewage channels along its length, and each sewage channel is connected to the sewage inlet at the bottom and side wall of the primary sewage pipe.

9. The method for ecological seedling cultivation of giant freshwater prawns in a land-based circular pond according to claim 1, characterized in that: The bottom of the aquaculture tank is conical, and a nano-aeration pipe is laid at the bottom of the aquaculture tank. A water inlet pipe is vertically installed on the side wall of the aquaculture tank, and water outlet holes are evenly distributed along the length of the water inlet pipe. The water outlet holes are horizontal and inclined relative to the axis of the aquaculture tank. A heating pipe for heating the water is laid inside the aquaculture tank.

10. The system for the land-based circular pond ecological seedling cultivation method for giant freshwater prawns according to claim 1, characterized in that: include: Culture tanks are used for the rearing of giant freshwater prawn larvae. The water purification unit includes a microfilter, a microalgae treatment tank, a disinfection tank, and a purified water tank connected in sequence. The microalgae cultivation unit is used for cultivating microalgae, which is then introduced into the cultivation tanks through a mixing pipeline. Sedimentation tanks are used to settle and filter wastewater discharged from water purification units.

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