A method for efficiently cultivating high-quality seedlings of the luxurious scallop "Nan'ao Jinbei"

Abstract

The present invention provides a method for efficiently cultivating high-quality seedlings of the elegant comb scallop "Nan'ao Jinbei." Based on the biological characteristics of plankton, which "hibernate during the day and sink at night," and utilizing the principle of microecological balance, the method changes the position of the aerated air stone used in traditional methods from being laid flat on the pond bottom to being suspended 1 / 3 to 1 / 2 below the water surface. This allows planktonic larvae and single-celled phytoplankton algae to live in the middle and upper layers of the water body under low light conditions, thereby cultivating the seedlings. Continuous aeration is performed during the seedling cultivation period, and the amount of aeration increases as the larvae grow. No water changes, pond draining, or antibiotic addition are required throughout the entire planktonic larval stage. Seedlings cultivated using the present invention grow more than 10% faster and produce nearly 40% more seedlings than those cultivated using traditional methods. This method also saves significant electricity and labor costs, reduces the discharge of seedling cultivation wastewater, and reduces the use of antibiotics. Therefore, the present method offers the advantages of high efficiency, low cost, and environmental friendliness.

Description

Technical Field

[0001] The invention belongs to the field of marine aquaculture and relates to a method for efficiently cultivating high-quality seedlings of the luxurious scallop "Nan'ao Jinbei". Background Art

[0002] Artificial propagation of shellfish seed is one of the most important aspects of shellfish aquaculture. It holds several important significances: 1. It can compensate for the shortage of natural seed; 2. It allows for stable and planned production; 3. It can advance or delay seeding, improving efficiency and profitability; and 4. It allows for targeted seed selection and breeding. Therefore, artificial propagation of shellfish seed has always been a priority for shellfish aquaculture companies.

[0003] The elegant scallop "Nan'ao Golden Scallop" (abbreviated as "Nan'ao Golden Scallop") is a national-level new variety bred by Shantou University through targeted breeding technology. It has four major advantages: "three highs and one strong": high sensory quality, high nutritional value, high aquaculture efficiency, and strong resistance to adversity. Once bred, the "Nan'ao Golden Scallop" was highly favored by aquaculture operators and consumers, and its aquaculture was quickly promoted in my country's southern waters, generating huge economic and social benefits. The elegant scallop is an important marine aquaculture shellfish in southern my country. Since the successful cultivation of artificial seedlings in the late 1970s, it has been widely cultivated in coastal areas of Guangdong, Guangxi, Fujian, Hainan and other places in my country. For more than 40 years, all the elegant scallop seedlings cultivated in southern my country have come from indoor artificial breeding (conventional breeding), and there have been many reports on the artificial breeding technology of elegant scallops. The conventional breeding process of the elegant scallop generally includes: 1. Selection of seed shellfish, 2. Induction of spawning, 3. Fertilization and hatching, 4. Cultivation of planktonic larvae (usually at a depth of 1.5 to 2 meters at 20 to 30 meters). 3 5. Placement of substrate. Since the water needs to be changed 1-2 times a day and the pond needs to be emptied every 2-3 days during the entire seedling cultivation period, this conventional seedling cultivation technology has the following problems: ① Planktonic larvae are easily harmed, resulting in low seedling cultivation efficiency; ② It consumes a large amount of water, electricity, and human resources, resulting in high seedling cultivation costs; ③ The wastewater discharged from the seedling cultivation will cause certain pollution to the environment, which is not environmentally friendly.

[0004] With the implementation of my country's "Dual Carbon" strategy, the country is vigorously advocating for a green, environmentally friendly, and low-carbon lifestyle. Furthermore, with the country's economic and social development, labor costs are also increasing. Therefore, to enhance the global competitiveness of industry and the economy, it is imperative to accelerate the reduction of carbon emissions and the development of green innovative technologies, while also reducing labor costs. However, the current production of noble scallop seedlings still relies on conventional seedling cultivation techniques. Therefore, the development of an efficient, low-cost, and environmentally friendly technology for the cultivation of noble scallop seedlings is highly desirable. Summary of the Invention

[0005] The present invention provides a method for efficiently cultivating high-quality seedlings of the noble scallop "Nan'ao Jinbei". By changing the position of an inflatable air stone in a nursery pond, the method can achieve the goal of not changing water or emptying the pond during the entire planktonic larval stage, thereby solving the problems of low efficiency, high cost, and environmental pollution in conventional nursery of the noble scallop.

[0006] A method for efficiently cultivating high-quality seedlings of the luxurious comb scallop "Nan'ao Golden Shell" comprises the following steps: selecting seed scallops, inducing spawning, fertilizing, hatching, cultivating planktonic larvae, placing attachment substrates, and managing the seedlings after attachment. During the cultivation of planktonic larvae, an inflatable air stone in a nursery pond is vertically suspended 1 / 3 to 1 / 2 below the water surface, and the pond is continuously inflated, with the amount of inflation increasing as the larvae grow. The indoor light intensity is controlled to be less than 50 lux, thereby efficiently cultivating high-quality seedlings of the luxurious comb scallop "Nan'ao Golden Shell".

[0007] Furthermore, the density of the inflatable air stones is 0.5-2 per square meter of water surface.

[0008] A method for efficiently cultivating high-quality seedlings of the luxurious scallop "Nan'ao Jinbei" mainly comprises the following steps:

[0009] (1) Selection of broodstock: Select healthy, undamaged, and fully-grown adult “South Australia Golden Clams” as broodstock;

[0010] (2) Artificial induction of labor: injecting 5-hydroxytryptamine into the gonads of the parent shellfish to induce labor;

[0011] (3) Fertilization and incubation: Sperm is added to the incubation pool containing the eggs for artificial insemination. After the eggs are fully fertilized, water is added to the incubation pool for incubation;

[0012] (4) Planktonic larvae culture: D-shaped larvae are collected from the hatching pond and transferred to the nursery pond for planktonic larvae culture;

[0013] (5) Placement of attachment base: When the number of eyed larvae reaches more than 30%, place brown rope as attachment base. The amount of attachment base is based on the number of larvae in the water body.

[0014] (6) Management after seedling attachment.

[0015] Furthermore, in step (4), the water body for culturing and raising planktonic larvae is 90% of the volume of the pond, the larvae density is 3 to 4 per mL, the water temperature can be 25 to 28° C., the natural seawater salinity is 28 to 32, golden algae are fed once a day for the first 5 days, 5,000 to 10,000 algal cells per mL of water, and golden algae and small diatoms are fed once a day, 10,000 to 30,000 algal cells per mL of water; after 8 to 9 days, eye spots appear on the larvae; and during the entire planktonic larval culture period, no water change, no pond inversion, and no antibiotics are added. Preferably, in step (4), the planktonic larvae are cultured and nursed in water of 90% of the pond volume, the larvae density is 4 cells / mL, the water temperature can be 25°C, the natural seawater salinity is 28, golden algae are fed once a day for the first 5 days, 5000 algae cells / mL of water, and golden algae and small diatoms are fed once a day at 10000 algae cells / mL of water; after 8 to 9 days, the larvae develop eye spots; during the entire planktonic larvae culture period, no water change, no pond inversion, and no antibiotics are added.

[0016] Furthermore, in step (6), the management of the seedlings after attachment is as follows: the water is completely changed once every three days, flat algae + diatoms are fed once a day, 30,000 to 50,000 algae cells / mL of water, preferably 30,000 algae cells / mL of water, and continuous aeration is performed; when the seedlings grow to a size of 500 μm or more, they reach the specifications for leaving the pond.

[0017] Furthermore, the indoor light intensity is 20-40 lux.

[0018] The technical principle of the present invention is as follows: based on the biological characteristics of plankton that "hibernate during the day and sink at night", and utilizing the principle of microecological balance, by changing the position of the inflatable air stone in the traditional method (from the bottom of the pond to 1 / 3 to 1 / 2 from the water surface), under low light conditions, both planktonic larvae and single-celled phytoplankton microalgae live in the middle and upper layers of the nursery pond water body, while feces, corpses or impurities all settle to the bottom of the water body, thereby forming a microecologically balanced environment in the middle and upper layers of the water body. During the entire planktonic larval stage, no water changes, no pond inversion, and no antibiotics are required. Utilizing the technology of the present invention not only improves seedling cultivation efficiency, but also saves seedling cultivation costs (labor, electricity, and reagents and drugs) and is environmentally friendly by not changing water, no pond inversion, and no antibiotics.

[0019] Compared with conventional seedling cultivation, the present invention has the following advantages:

[0020] 1. High efficiency. The larvae cultivated by the present invention not only grow fast, but also have significantly improved survival rate, attachment rate and emergence rate, thus achieving high efficiency. The seedlings grow more than 10% faster and the emergence rate is nearly 40% higher.

[0021] 2. Low cost. The present invention does not require emptying the pond, changing water, or adding antibiotics, and the labor and material costs are significantly lower than traditional methods.

[0022] 3. Ecological and environmental protection: The present invention reduces the discharge of wastewater from seedling cultivation in traditional methods and does not require the feeding of antibiotics, thus being ecological and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a photo of the planktonic larvae cultured in the nursery pond of workshop 1# in Example 1;

[0024] Figure 2 This is a photograph of the metamorphosed spat obtained by culture in Example 1;

[0025] Figure 3 This is a photo of the larvae cultured in the nursery pond of workshop 1# in Example 1 under a microscope;

[0026] Figure 4 This is a photo taken under a microscope of the juvenile spat cultured in the 1# workshop nursery pond in Example 1. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with specific examples and accompanying drawings. These examples are intended to illustrate the present invention only and are not intended to limit the scope of the invention. The experimental methods in the following examples where specific conditions are not specified are generally based on the conditions described in the conventional conditions.

[0028] Example 1:

[0029] Time: March 2021-April 2021, Location: Scallop nursery of Longyuanfa Aquaculture Professional Cooperative, Raoping County (Chengnan Village, Dacheng Town, Raoping County, Chaozhou City).

[0030] On March 21, 2021, 1,800 healthy, undamaged, and gonadal-filled "Nan'ao Golden Clams" were selected, and D-shaped larvae were obtained through artificial induction of labor, insemination, and hatching. Then, 20 40m2 larvae were used in both the 1# and 2# nursery workshops. 3 In a nursery pond with the same water body (5m long × 4m wide × 2m deep), planktonic larvae were cultured using the present invention and conventional nursery methods, with eyespots appearing on the 9th day, substrates added on the 10th day, and seedlings removed from the pond on the 28th day. The specific steps are as follows:

[0031] 1. Selection of parent shellfish: Select 1,800 healthy, undamaged, and fully gonadal "South Australia Golden Shellfish".

[0032] 2. Artificial induction of spawning. Inject 0.01 mL of 0.02 mM 5-HT into the gonads of each parent oyster. Then, separate the male and female oysters in a spawning tank or bucket. After 10 minutes, the parent oysters will begin spawning and ejaculating. When the number of eggs and sperm reaches a certain level, remove the parent oysters and transfer the eggs to an incubation tank. Fill the incubation tank with water to maintain an egg density of approximately 50 eggs / mL.

[0033] 3. Fertilization and Incubation. Artificial insemination is performed by adding a certain amount of sperm to the incubation tank containing the eggs. Microscopic examination shows four sperm surrounding each egg. Fertilization is complete and incubation is initiated. The incubation water temperature is 25°C and the salinity of natural seawater is 28°C. During the incubation period, the water is manually agitated every three hours. After 28 hours, the fertilized eggs develop into D-shaped larvae.

[0034] 4. Planktonic larvae culture: D-shaped larvae were collected from the hatching pond using a 400-mesh screen and transferred to a total of 40 nursery ponds in workshops 1 and 2 for planktonic larvae culture. The pond water was filled to a depth of 180 cm. In workshop 1 (using the present invention), the inflated air stone in the nursery pond was vertically suspended 60 cm below the water surface. Feed was given once a day without water changes or pond inversion. In workshop 2 (using conventional nursery), the air stone in the nursery pond was laid flat on the pond bottom. The water was changed twice a day, and the pond was inverted once every three days, with three people working each time. Feed was given after each water change or pond inversion. The initial larvae density in both nurseries was 4 larvae / mL, the water temperature was 25°C, the natural seawater salinity was 28, one air stone was used per square meter for continuous aeration, and the light intensity was 40 lux. The total daily feed volume was the same, increasing as the larvae grew. For the first five days, they were fed golden algae at 5,000 algal cells / mL of water, followed by golden algae and small diatoms at 10,000 algal cells / mL of water. However, in Workshop 1, feed was administered once daily, while in Workshop 2, feed was administered once after each water change and tank drain. On day 9, larval survival in Workshop 1 was 68.5 ± 3.6%, with an eyed larval rate of 8.3 ± 0.4%, while in Workshop 2, the survival rate was 52.5 ± 5.7%, with an eyed larval rate of 3.4 ± 0.6%. On day 10, larval survival in Workshop 1 was 57.5 ± 4.4%, with an eyed larval rate of 38.4 ± 2.2%, while in Workshop 2, the survival rate was 41.5 ± 4.6%, with an eyed larval rate of 25.4 ± 6.5%. No antibiotics were added throughout the larval incubation period.

[0035] 5. Place the attachment base: Place the coir rope attachment base on the 10th day in workshop 1#, and place the coir rope attachment base on the 11th day in workshop 2#; 500 coir ropes are placed in each pool, each coir rope is 1.5m long and 1.5cm in diameter.

[0036] 6. Management after seedling attachment. The water in workshop 1# is fully changed every 3 days, and in workshop 2#, it is fully changed every day. Both workshops are fed with flat algae + diatoms once a day, 30,000 algae cells / mL of water, and are continuously aerated. On the 17th day, the seedling attachment rate was measured by sampling: workshop 1# was 95.6±6.5%, and workshop 2# was 85.8±7.2%. On April 16, the seedling specifications (shell length) and seedling quantity (grains / root coir rope) were randomly inspected: the seedling specifications of workshop 1# were 512.6±10.1μm, and the seedling quantity was 13,200 grains / root coir rope, and the seedlings did not meet the specifications for leaving the pond; the seedling specifications of workshop 2# were 452.5±15.7μm, and the seedling quantity was 9,500 grains / root coir rope, and the seedlings did not meet the specifications for leaving the pond. The seedling output of workshop 1# was 38.95% more than that of workshop 2#.

[0037] The above examples show that the seedlings cultivated by the present invention not only grow 13.28% faster than the traditional method, but also produce 38.95% more seedlings than the traditional method, while also saving 3 seedling workers and 2,200 yuan in electricity costs. In addition, the wastewater discharge from seedling cultivation is reduced by 400m3 per day. 3 Therefore, the present invention has the advantages of high efficiency, low cost, and environmental protection.

[0038] Example 2:

[0039] Time: September 2021 - October 2021, Location: Scallop hatchery of Longyuanfa Aquaculture Professional Cooperative, Raoping County (Chengnan Village, Dacheng Town, Raoping County, Chaozhou City).

[0040] On September 12, 2021, 2,000 healthy, undamaged, and gonadal-filled "Nan'ao Golden Clams" were selected, and D-shaped larvae were obtained through artificial induction of labor, insemination, and hatching. Then, 20 40m2 larvae were used in both the 1# and 2# nursery workshops. 3 In a nursery pond with the same water body (5m long × 4m wide × 2m deep), planktonic larvae were cultured using the present invention and conventional nursery methods. On the 8th day, the larvae developed eyespots, the culturing medium was added on the 9th day, and the fry were removed from the pond on the 25th day. The specific steps are as follows:

[0041] 1. Selection of parent shellfish: Select 2,000 healthy, undamaged, and fully gonadal "South Australia Golden Shellfish".

[0042] 2. Artificial induction of spawning. Inject 0.01 mL of 0.02 mM 5-HT into the gonads of each parent oyster. Then, separate the male and female oysters in a spawning tank or bucket. After 10 minutes, the parent oysters will begin spawning and ejaculating. When the number of eggs and sperm reaches a certain level, remove the parent oysters and transfer the eggs to an incubation tank. Fill the incubation tank with water to maintain an egg density of approximately 50 eggs / mL.

[0043] 3. Fertilization and Incubation. Artificial insemination is performed by adding a certain amount of sperm to the incubation tank containing the eggs. Microscopic examination shows four sperm surrounding each egg. Fertilization is complete and incubation is initiated. The incubation water temperature is 28°C and the salinity of natural seawater is 32°C. During the incubation period, the water is manually agitated every three hours. After 20 hours, the fertilized eggs develop into D-shaped larvae.

[0044] 4. Cultivation of floating larvae: D-shaped larvae were collected from the hatching pond using a 400-mesh screen and transferred to a total of 40 nursery ponds in workshops 1 and 2 for cultivation of floating larvae. The pond water was filled to a depth of 180 cm. In workshop 1 (using the present invention), the inflatable air stone in the nursery pond was vertically suspended 90 cm below the water surface. Feed was given once a day without water changes or pond inversion. In workshop 2 (using conventional nursery), the air stone in the nursery pond was laid flat on the pond bottom. The water was changed twice a day, and the pond was inverted once every three days, with three people working each time. Feed was given after each water change or pond inversion. The initial larval density in both workshops was 5 larvae / mL, the water temperature was 28°C, the natural seawater salinity was 30, one air stone was used per square meter for continuous inflation, and the indoor light intensity was 30 lux. The total daily feed volume was the same: golden algae at 10,000 algal cells / mL of water for the first five days, followed by golden algae and small diatoms at 30,000 algal cells / mL of water. However, in Workshop 1, feed was administered once daily, while in Workshop 2, feed was administered once after each water change and tank draining. On day 8, larval survival in Workshop 1 was 78.4 ± 3.2%, with an eyed larval rate of 15.5 ± 0.6%, while that in Workshop 2 was 61.6 ± 5.2%, with an eyed larval rate of 6.6 ± 0.8%. On day 9, larval survival in Workshop 1 was 70.5 ± 4.5%, with an eyed larval rate of 42.6 ± 2.5%, while that in Workshop 2 was 43.6 ± 4.1%, with an eyed larval rate of 26.6 ± 5.8%. No antibiotics were added throughout the larval incubation period.

[0045] 5. Place the attachment base: Place the coir rope attachment base on the 9th day in workshop 1#, and place the coir rope attachment base on the 10th day in workshop 2#; 500 coir ropes are placed in each pool, each coir rope is 1.5m long and 1.5cm in diameter.

[0046] 6. Management after seedling attachment. The water in workshop 1# is fully changed every 3 days, and in workshop 2#, it is fully changed every day. Both workshops are fed with flat algae + diatoms once a day, 50,000 algae cells / mL of water, and are continuously aerated. On the 16th day, the seedling attachment rate was measured by sampling: workshop 1# was 100%, and workshop 2# was 93.4±7.5%. On October 15, the seedling specifications (shell length) and seedling quantity (grains / root coir rope) were randomly inspected: the seedling specifications of workshop 1# were 528.4±12.2μm, and the seedling quantity was 19,800 grains / root coir rope, and the seedlings did not meet the specifications for leaving the pond; the seedling specifications of workshop 2# were 461.8±16.6μm, and the seedling quantity was 14,080 grains / root coir rope, and the seedlings did not meet the specifications for leaving the pond. The seedling output in workshop 1# was 40.63% more than that in workshop 2#.

[0047] The above examples show that the seedlings grown by the present invention not only grow 14.42% faster than conventional seedling cultivation, but also produce 40.63% more seedlings than conventional seedling cultivation. It also saves 3 seedling cultivation workers and 2,200 yuan in electricity costs. In addition, the wastewater discharge from seedling cultivation is reduced by 400m3 per day. 3 Therefore, the present invention has the advantages of high efficiency, low cost, and environmental protection.

[0048] Example 3:

[0049] Time: March 2022-April 2021, Location: Shellfish Hatchery of Shantou Nan'ao Gengtaiyang Aquatic Products Co., Ltd. (Aoqian Village, Yun'ao Town, Nan'ao County).

[0050] On March 18, 2021, 2,500 healthy, undamaged, and gonadal-filled "Nan'ao Golden Clams" were selected, and D-shaped larvae were obtained through artificial induction of labor, insemination, and hatching. Then, 20 50m2 larvae were used in both the 1# and 2# nursery workshops. 3 In a nursery pond with the same water body (5m long × 5m wide × 2m deep), planktonic larvae were cultured using the present invention and conventional nursery methods, with eyespots appearing on the 9th day, substrates added on the 10th day, and seedlings removed from the pond on the 27th day. The specific steps are as follows:

[0051] 1. Selection of parent shellfish: Select 2,500 healthy, undamaged, and fully gonadal "South Australia Golden Shellfish".

[0052] 2. Artificial induction of spawning. Inject 0.01 mL of 0.02 mM 5-HT into the gonads of each parent oyster. Then, separate the male and female oysters in a spawning tank or bucket. After 10 minutes, the parent oysters will begin spawning and ejaculating. When the number of eggs and sperm reaches a certain level, remove the parent oysters and transfer the eggs to an incubation tank. Fill the incubation tank with water to maintain an egg density of approximately 50 eggs / mL.

[0053] 3. Fertilization and Incubation. Artificial insemination is performed by adding a certain amount of sperm to the incubation tank containing the eggs. Microscopic examination shows that four sperm are present around each egg. Fertilization is complete and incubation is then initiated. The incubation water temperature is 26°C and the salinity of natural seawater is 30°C. During incubation, the water is manually stirred every three hours. After 25 hours, the fertilized eggs develop into D-shaped larvae.

[0054] 4. Cultivation of floating larvae: D-shaped larvae were collected from the hatching pond using a 400-mesh screen and transferred to five nursery ponds in workshops 1 and 2 for culturing floating larvae. The water in the nursery pond in workshop 1 (using the present invention) was filled to a depth of 180 cm. The air stone in the nursery pond in workshop 1 (using the present invention) was suspended vertically 70 cm below the water surface and fed once daily without water changes or pond inversion. The air stone in the nursery pond in workshop 2 (using conventional nursery) was laid flat on the pond bottom, with water changes twice daily and pond inversion every three days, performed by three people each time. Feeding was performed after each water change or pond inversion. The initial larval density in both nurseries was 4 larvae / mL, the water temperature was 25°C, the natural seawater salinity was 28, 0.5 air stones per square meter were used for continuous aeration, and the light intensity was 20 lux. The total daily feed volume was the same, increasing as the larvae grew. For the first five days, they were fed golden algae at 5,000 algal cells / mL of water, followed by golden algae and small diatoms at 10,000 algal cells / mL of water. However, in Workshop 1, feed was administered once daily, while in Workshop 2 was fed once after each water change and tank draining. On day 9, larval survival in Workshop 1 was 72.5 ± 3.4%, with an eyed larval rate of 10.2 ± 0.6%, while in Workshop 2, the survival rate was 55.6 ± 5.3%, with an eyed larval rate of 4.8 ± 0.8%. On day 10, larval survival in Workshop 1 was 60.6 ± 3.8%, with an eyed larval rate of 40.5 ± 2.5%, while in Workshop 2, the survival rate was 40.3 ± 4.1%, with an eyed larval rate of 24.6 ± 5.8%. No antibiotics were added throughout the larval incubation period.

[0055] 5. Placement of attachment base: Palm rope attachment base was placed in workshop 1# on the 10th day, and in workshop 2# on the 11th day; 600 palm ropes were placed in each pool, each with a length of 1.5m and a diameter of 1.5cm.

[0056] 6. Management after seedling attachment. The water in workshop 1# is fully changed every 3 days, and in workshop 2#, it is fully changed every day. Both workshops are fed with flat algae + diatoms once a day, 30,000 algae cells / mL of water, and are continuously aerated. On the 17th day, the seedling attachment rate was measured by sampling: workshop 1# was 96.2±5.1%, and workshop 2# was 88.4±6.6%. On April 16, the seedling specifications (shell length) and seedling quantity (grains / root coir rope) were randomly inspected: the seedling specifications of workshop 1# were 515.2±10.2μm, and the seedling quantity was 13,600 grains / root coir rope, and the seedlings did not meet the specifications for leaving the pond; the seedling specifications of workshop 2# were 455.6±12.8μm, and the seedling quantity was 9,800 grains / root coir rope, and the seedlings did not meet the specifications for leaving the pond. The seedling output of workshop 1# was 38.78% more than that of workshop 2#.

[0057] The above examples show that the seedlings cultivated by the present invention not only grow 13.08% faster than conventional seedling cultivation, but also produce 38.78% more seedlings than conventional seedling cultivation. It also saves 3 seedling cultivation workers and 2,500 yuan in electricity costs. In addition, the wastewater discharge from seedling cultivation is reduced by 500m3 per day. 3 Therefore, the present invention has the advantages of high efficiency, low cost, and environmental protection.

[0058] In addition, any method of efficiently cultivating shellfish seedlings without changing water, emptying the pond, or adding antibiotics by changing the position of the aerated air stone in the seedling water body is also within the scope of the creative ideas described in the present invention.

Claims

1. A method for efficiently cultivating high-quality seedlings of the luxurious scallop "Nan'ao Jinbei" comprises: during the cultivation of planktonic larvae, vertically suspending an inflatable air stone in a nursery pond 1 / 3 to 1 / 2 below the water surface, continuously inflating the pond, increasing the amount of air as the larvae grow, controlling the indoor light intensity to 20-40 lux, and not changing the water or emptying the pond during the entire planktonic larval stage; the density of the inflatable air stone is 0.5-2 per square meter of water surface.

2. The method according to claim 1, characterized in that The following steps are involved: (1) Selection of broodstock: Select healthy, undamaged, and fully-grown adult "South Australia Golden Clams" as broodstock; (2) Artificial induction of labor: Injecting 5-hydroxytryptamine into the gonads of the parent shellfish to induce labor; (3) Fertilization and incubation: Sperm is added to the incubation pool containing the eggs for artificial insemination. After the eggs are fully fertilized, water is added to the incubation pool for incubation; (4) Planktonic larvae culture: Collect D-shaped larvae from the hatching pond and transfer them to the nursery pond for planktonic larvae culture; (5) Placement of attachment base: When the number of eyed larvae reaches more than 30%, place brown rope as attachment base. The amount of attachment base should be based on the number of larvae in the water body. (6) Management after seedling attachment.

3. The method according to claim 2, characterized in that In step (4), the planktonic larvae are cultured and nursed in water of 90% of the pond volume, with a larval density of 4 cells / mL, a water temperature of 25°C, a natural seawater salinity of 28, and golden algae are fed once a day for the first 5 days at a density of 5,000 algal cells / mL of water. Thereafter, golden algae and small diatoms are fed once a day at a density of 10,000 algal cells / mL of water. Eye spots appear in the larvae after 8 to 9 days. During the entire planktonic larval culture period, no water changes, no pond inversions, and no antibiotics are added.

4. The method according to claim 2, characterized in that The management of the seedlings after attachment in step (6) is as follows: change the water once every three days, feed the algae + diatoms once a day, 30,000 algal cells / mL of water, and continuously aerate; when the seedlings grow to a size of more than 500µm, they reach the specifications for leaving the pond.

Images