A method for synergistically enhancing the survival rate of vannamei shrimp by probiotics and nutrients

Abstract

The application discloses a method for synergistically strengthening Litopenaeus vannamei with probiotics and nutrients, and technical solution points of the method comprise the following steps: preparing water for breeding Litopenaeus vannamei, preparing a breeding pond, adding a probiotic group into the breeding pond, cultivating nauplii, adding chondrophycus into the breeding pond, cultivating copepodid larvae, feeding rotifer into the breeding pond, cultivating brine shrimp larvae, feeding shrimp slices into the breeding pond, feeding rotifer and brine shrimp nauplii together, cultivating postlarvae, feeding shrimp slices and brine shrimp nauplii into the breeding pond, and feeding rotifer, shrimp slices and brine shrimp nauplii after synergistic strengthening with probiotics and nutrients. The method has the advantages that the postlarvae feed is synergistically strengthened with probiotics and nutrients, the problems of large water spraying amount, easy strain inactivation and short effect period are avoided, the postlarvae is convenient to feed, the intestinal tract of the postlarvae is regulated, the digestion and absorption of nutritional components are promoted, the disease resistance of the postlarvae is improved, and the effect of promoting the production and cultivation of high-quality postlarvae is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of Penaeus vannamei culture, and in particular to a Penaeus vannamei seedling culture method with synergistic enhancement of probiotics and nutrients. Background Art

[0002] Litopenaeus vannamei, commonly known as the South American whiteleg shrimp, is a commercial marine species with a wide range of temperatures and salinities. Its aquaculture output exceeds 2 million tons, and its seed production exceeds 1 trillion. The sustainable development of the vannamei shrimp industry currently relies on the supply of high-quality seed.

[0003] From hatching to adulthood, shrimp larvae undergo four metamorphosis stages. The transition from zoea to mysid larvae and from mysid larvae to postlarvae are two critical periods in shrimp nursery. Larval mortality is frequent during these stages, with bacterial infection being a key factor. Years of experimental research have shown that the total bacterial counts in diseased nursery pond water and in diseased larvae are significantly higher than those in healthy pond water and larvae, with pathogens of the genus Vibrio, primarily Vibrio parahaemolyticus, comprising the majority of these bacteria. Therefore, preventing Vibrio infections during the development of Litopenaeus vannamei larvae is a key challenge in shrimp nursery.

[0004] Probiotics are beneficial microorganisms that can colonize the shrimp intestines or improve the quality of nursery water. They can enhance the growth performance of Penaeus vannamei and maintain the nursery water environment, and generally do not have a negative impact on the juveniles. Probiotics are widely used in shrimp nursery to optimize the water quality of nursery water. Their application as feed improvers and immunostimulants is still in the early stages of development. Currently, in the production of Penaeus vannamei nursery, probiotics are mostly applied by spraying water. This application method has many problems, such as large amounts of bacterial solution, easy inactivation of strains in water, and a short effective period. These problems greatly reduce the beneficial effects of probiotics, thereby reducing the effectiveness of shrimp nursery.

[0005] During the development of Penaeus vannamei larvae, they also need to consume a large amount of nutrients, but these existing nutrients can only provide basic nutrition during the seedling rearing process, and cannot reduce or inhibit the growth of harmful bacteria such as Vibrio in the larvae. Summary of the Invention

[0006] In response to the shortcomings of the existing technology, the present invention provides a method for cultivating shrimp fry with synergistically enhanced probiotics and nutrients. The method has the advantages of synergistically strengthening the shrimp fry bait with probiotics and nutrients, avoiding the problems of large direct water spraying, easy inactivation of strains, and short effective period. It is convenient for shrimp fry to directly feed, regulates the intestinal microbial flora of shrimp, promotes digestion and absorption of nutrients, improves the disease resistance of shrimp fry, and thus promotes the production and cultivation of high-quality shrimp fry.

[0007] To achieve the above object, the present invention provides the following technical solution: a method for raising shrimp seedlings with synergistic enhancement of probiotics and nutrients, comprising the following steps:

[0008] Step 1: Preparation of water for shrimp seedling cultivation:

[0009] (1) The water used for shrimp seedling cultivation can be natural seawater from the sea area adjacent to the shrimp seedling cultivation area. The natural seawater is preliminarily treated by sedimentation, sand filtration, nitrification, etc. to make the water body of the natural seawater clear and transparent, thus obtaining first-class seedling cultivation water;

[0010] (2) The salinity of the first-level seedling water is adjusted by concentration and desalination, so that the salinity of the water is controlled at 29-30‰. Then, chlorine-containing disinfectant is added to the water, and the concentration is controlled at 25ppm. The disinfection time is controlled at 24h. The water is then aerated to make the water tumble. The aeration time is controlled at more than 10h. Finally, sodium thiosulfate solution is sprayed into the water to neutralize the residual chlorine in the water, thereby obtaining the second-level seedling water.

[0011] (3) Sprinkle activated carbon powder into the secondary seedling water, and then evenly sprinkle disodium ethylenediaminetetraacetic acid (EDTA) into the water. Disodium ethylenediaminetetraacetic acid (EDTA) can chelate heavy metals such as lead, mercury, cadmium, chromium, and arsenic, and then obtain the tertiary seedling water;

[0012] Step 2: Preparation of the nursery pond:

[0013] (1) Use 100ppm chlorine-containing disinfectant to flush the nursery pond used for shrimp cultivation, then transfer the water used for shrimp cultivation to the nursery pond, control the water storage capacity at 60%, and then adjust the water temperature to 28~30℃ through the heating facilities of the nursery pond. At the same time, aerate the water in the nursery pond so that the water surface is slightly boiling;

[0014] (2) Probiotics were added to the water in the nursery pond. The probiotics included Bacillus subtilis, Bacillus licheniformis and Lactobacillus plantarum, and the bacterial content in the water was set to 1×10 4 CFU / mL, 2×10 3 CFU / mL and 2×10 3 CFU / mL, 24 h after adding probiotics, nauplii were released;

[0015] Step 3: Cultivation of nauplii:

[0016] (1) Nauplii were released into the water of the nursery pond where probiotics had been added for more than 24 hours, with a density of 150,000 to 250,000 nauplii / mL, and then vitamin C powder was sprinkled into the water of the nursery pond;

[0017] (2) After the nauplii were cultured for 40 hours, Chaetoceros was added to the water in the nursery pond, and the cell density was controlled at 300,000 to 400,000 cells / mL; Chaetoceros is a high-temperature resistant variety.

[0018] (3) The nauplii in the nursery pond will metamorphose into zoeae within 48 hours. During the nauplii culture period, shrimp culture water should be added to the nursery pond every day, and the amount of shrimp culture water added should be controlled at 10% of the total water volume in the nursery pond. During the nauplii culture period, there is no need to add bait to the nursery pond. Nauplii use their own yolk as a nutrient source, so no external bait is needed.

[0019] Step 4: Cultivation of zoeae;

[0020] The development of zoeae to mysid larvae is divided into three cycles. When zoeae develop to stage I, they are fed with Chaetoceros algae in the nursery pond. When zoeae develop to stages II and III, they are fed with treated rotifers, with a feeding rate of 15 to 20 million Brachionus plicatilis for every one million zoeae. During the cultivation period of zoeae, shrimp nursery water is added to the nursery pond every day, and the amount of water added is controlled to be 10% of the total water volume in the nursery pond.

[0021] Step 5: Cultivation of Mysid Shrimp Larvae:

[0022] Feed the nursery ponds with processed shrimp flakes at a rate of 30g per million mysid shrimp larvae. Simultaneously, feed the nursery ponds with a mixture of processed rotifers and Artemia nauplii at a density of 5-6 rotifers / mL and 0.5-1 Artemia nauplii / mL. During the mysid shrimp larvae rearing period, add shrimp nursery water to the nursery ponds daily, controlling the amount of water added to 10% of the total water volume.

[0023] Step 6: Cultivation of shrimp larvae:

[0024] (1) Feed the nursery pond with processed shrimp flakes, 40g of shrimp flakes per million shrimp larvae, twice a day, morning and evening; and replace 20% of the water in the nursery pond with fresh water every day. The water temperature should be maintained at 30-31℃, and the nitrite content in the water should be less than 0.1mg / L and the total ammonium nitrogen content should be less than 0.3mg / L.

[0025] (2) During the rearing period of shrimp larvae, they need to be fed with processed Artemia nauplii; the feeding amount for shrimp larvae in the P1 stage is 10 million Artemia nauplii for every one million shrimp larvae, and then the feeding amount is increased by 10% every day; shrimp larvae can be hatched when they reach the P5~P10 stage, and the shrimp fry are transported long distances in oxygenated packages.

[0026] By adopting the above technical solution, probiotics are added to the water in the nursery pond to inhibit Vibrio in the water of the nursery pond, and by feeding shrimp fry with processed rotifers, shrimp flakes, artemia nauplii and other shrimp fry baits, Vibrio in the shrimp fry can be inhibited, thereby improving the survival rate and seed quality of the shrimp fry.

[0027] The present invention is further configured as follows: the treated rotifers are strengthened by using a rotifer strengthening material, and after strengthening for 12 hours, impurities and dead worms are separated to obtain the treated rotifers, and the rotifer strengthening material includes Bacillus subtilis, Lactobacillus plantarum, Lactobacillus valerate, Lactobacillus rhamnosus, concentrated Nannochloropsis, concentrated deep-sea fish oil, and vitamin C.

[0028] By adopting the above technical solution, the probiotics in the rotifer-enhanced material are convenient for shrimp fry to directly ingest, while regulating the intestinal microbial flora of the shrimp, promoting the digestion and absorption of nutrients, inhibiting the growth of harmful bacteria such as Vibrio, and improving the quality of the shrimp fry; the content of DHA and EPA in the nutritional composition of rotifers is lower than the nutritional requirement of shrimp larvae, so concentrated microgreens and concentrated deep-sea fish oil are added to the rotifer-enhanced material to increase the DHA and EPA content to enhance the nutritional composition of the rotifers, thereby improving the growth and metamorphosis rate of shrimp larvae.

[0029] The present invention is further configured as follows: the rotifer strengthening material is prepared by mixing 500 mL of Bacillus subtilis, 500 mL of Lactobacillus plantarum, 500 mL of Lactobacillus valerate, 500 mL of Lactobacillus rhamnosus, 800 mL of concentrated Nannochloropsis algae, 15 mL of concentrated deep-sea fish oil, and 30 g of vitamin C; each portion of the rotifer strengthening material can be used to strengthen 100 million rotifers, and the bacterial concentrations of Bacillus subtilis, Lactobacillus plantarum, Lactobacillus valerate, and Lactobacillus rhamnosus in the rotifer strengthening material are not less than 1×10 8 CFU / mL.

[0030] By adopting the above technical solution, the rotifer-enhanced material is convenient for shrimp fry to directly ingest, regulates the intestinal microbial flora of shrimp, promotes the digestion and absorption of nutrients, inhibits the growth of harmful bacteria such as Vibrio, and improves the quality of shrimp fry.

[0031] The present invention is further configured as follows: the processed shrimp chips are shrimp microcapsule feed, the shrimp chips are scrubbed with a 200-mesh mesh bag, and the liquid used during scrubbing is a probiotic solution I, 10 L of the probiotic solution I is used for every 100 g of shrimp chips, the scrubbed shrimp chips are placed in a constant temperature culture chamber for fermentation, and the processed shrimp chips are obtained after fermentation for 5 to 6 hours.

[0032] By adopting the above technical solution, the fermented shrimp chips contain beneficial microorganisms, which are convenient for the shrimp fry to directly ingest. While providing the necessary nutrition, they also regulate the intestinal microbial flora of the shrimp, promote the digestion and absorption of nutrients, inhibit the growth of harmful bacteria such as Vibrio, and improve the quality of the shrimp fry.

[0033] The present invention is further configured as follows: the probiotic solution I includes Bacillus subtilis solution and Lactobacillus plantarum solution, the Bacillus subtilis solution and the Lactobacillus plantarum solution are uniformly mixed in equal proportions, and the bacterial contents in the Bacillus subtilis solution and the Lactobacillus plantarum solution are 1×10 9 CFU / mL and 1×10 8 CFU / mL.

[0034] By adopting the above technical solution, the probiotic solution I inhibits the growth of harmful bacteria such as Vibrio, increases the survival rate of shrimp larvae, and improves the quality of shrimp seedlings.

[0035] The present invention is further configured as follows: the processed Artemia nauplii are 3 80 million Artemia nauplii, 400 mL of probiotic solution II, 50 g of DHA enhancer, 30 g of astaxanthin, 10 g of multivitamins and 10 g of polysaccharide were sequentially added into the water to obtain treated Artemia nauplii.

[0036] By adopting the above technical solution, Artemia nauplii generally lack DHA. Adding DHA enhancers and other nutrients can improve the survival rate of shrimp larvae. Probiotic liquid II is convenient for shrimp fry to directly ingest, while regulating the intestinal microbial flora of shrimp, promoting the digestion and absorption of nutrients, inhibiting the growth of harmful bacteria such as Vibrio, and improving the quality of shrimp fry.

[0037] The present invention is further configured as follows: the probiotic liquid II includes Bacillus subtilis liquid, Bacillus licheniformis, Lactobacillus rhamnosus, Lactobacillus plantarum, Pediococcus pentosaceus, and Lactococcus lactis, and the Bacillus subtilis liquid, Bacillus licheniformis, Lactobacillus rhamnosus, Lactobacillus plantarum, Pediococcus pentosaceus, and Lactococcus lactis account for 25%, 25%, 12.5%, 12.5%, 12.5%, and 12.5% ​​of the total liquid, respectively.

[0038] By adopting the above technical solution, Probiotic Liquid II inhibits the growth of harmful bacteria such as Vibrio, increases the survival rate of shrimp larvae, and improves the quality of shrimp seedlings.

[0039] In summary, the present invention has the following beneficial effects:

[0040] 1. By adding probiotics to the water in the nursery pond, the Vibrio in the water of the nursery pond is suppressed, and by feeding the shrimp fry with processed rotifers, shrimp flakes and Artemia nauplii, the Vibrio in the shrimp fry is suppressed, thereby improving the survival rate and quality of the shrimp fry;

[0041] 2. By adding DHA and other nutrients to the rotifers and Artemia nauplii, the nutrients required for the growth of shrimp fry can be met, thereby improving the quality of shrimp fry. DETAILED DESCRIPTION

[0042] The present invention will be further described in detail below with reference to the accompanying drawings.

[0043] This embodiment discloses a method for cultivating shrimp seedlings with synergistic enhancement of probiotics and nutrients, comprising the following steps: Step 1: preparing water for cultivating shrimp seedlings:

[0044] (1) The water for shrimp seedling cultivation can be natural seawater from the sea area adjacent to the shrimp seedling cultivation area. The natural seawater can be preliminarily treated by sedimentation, sand filtration, nitrification, etc. to remove most of the sediment, microalgae, bacteria, debris, impurities and inorganic nitrogen in the seawater, making the water body of the natural seawater clear and transparent, thus obtaining first-class seedling cultivation water;

[0045] (2) The salinity of the first-level seedling water is adjusted by concentration and desalination, so that the salinity of the water is controlled at 29~30‰. Then, chlorine-containing disinfectant is added to the water, and the concentration is controlled at 25ppm. The disinfection time is controlled at 24h. Then, the water is aerated to make the water tumble. The aeration time is controlled at more than 10h. By aerating the water, harmful components such as hydrogen sulfide in the water can be removed. Finally, sodium thiosulfate solution is sprayed into the water to neutralize the residual chlorine in the water, thereby obtaining the second-level seedling water.

[0046] (3) Sprinkle activated carbon powder into the secondary seedling water to absorb harmful components such as microalgae toxins and chlorophenols in the water. Then, sprinkle disodium ethylenediaminetetraacetic acid (EDTA) evenly into the water. Disodium ethylenediaminetetraacetic acid (EDTA) can chelate heavy metals such as lead, mercury, cadmium, chromium, and arsenic, thereby improving the water quality and obtaining tertiary seedling water.

[0047] Step 2: Preparation of the nursery pond:

[0048] (1) Use 100ppm chlorine-containing disinfectant to flush the nursery pond used for shrimp cultivation to keep it clean and tidy. Then, transfer the water used for shrimp cultivation to the nursery pond, control the water storage capacity at 60%, and then adjust the water temperature to 28~30℃ through the heating facilities of the nursery pond. At the same time, aerate the water in the nursery pond so that the water surface is slightly boiling.

[0049] (2) Add the probiotics required for shrimp seedling cultivation to the water in the nursery pond. The probiotics include Bacillus subtilis, Bacillus licheniformis and Lactobacillus plantarum, and the bacterial content in the water is set to 1×10 4 CFU / mL, 2×10 3 CFU / mL and 2×10 3 CFU / mL. Inoculating beneficial microorganisms into water bodies can improve water quality and inhibit the growth of harmful bacteria such as Vibrio. Nauplii seeds are added 24 hours after adding probiotics.

[0050] Step 3: Cultivation of nauplii:

[0051] (1) Nauplii are released into the water of the nursery pond that has been supplemented with probiotics for more than 24 hours. The density of the released nauplii is 150,000 to 250,000 nauplii / mL. Vitamin C powder is then sprinkled into the water of the nursery pond. Vitamin C powder can alleviate the stress behavior of nauplii, allowing the nauplii to be successfully cultured in the nursery pond.

[0052] (2) After the nauplii were cultured for 40 hours, Chaetoceros was added to the water in the nursery pond. The cell density of the algae was controlled at 300,000 to 400,000 cells / mL. Chaetoceros effectively inhibited the growth of pathogens such as Vibrio parahaemolyticus and Vibrio alginolyticus, thus preventing the excessive number of pathogens from affecting the survival rate of the seedlings. Chaetoceros is a high-temperature resistant variety, mainly Chaetoceros muelleri.

[0053] (3) The nauplii in the nursery pond will metamorphose into zoeae within 48 hours. During the nauplii culture period, shrimp culture water should be added to the nursery pond every day, and the amount of shrimp culture water added should be controlled at 10% of the total water volume in the nursery pond. During the nauplii culture period, there is no need to add bait to the nursery pond. Nauplii use their own yolk as a nutrient source, so no external bait is needed.

[0054] Step 4: Cultivation of zoeae;

[0055] The development of zoeae into mysid larvae is divided into three cycles. When zoeae develop to stage I, they are fed with Chaetoceros algae in the nursery pond. When zoeae develop to stages II and III, they are fed with treated rotifers at a rate of 15 to 20 million rotifers per one million zoeae. The rotifers are the Brachionus plicatilis rotifers, which provide them with sufficient and balanced nutrition to support their successful metamorphosis into mysid larvae. During the cultivation period of zoeae, water for shrimp nursery is added to the nursery pond every day, and the amount of water added is controlled to be 10% of the total water volume in the nursery pond.

[0056] Step 5: Cultivation of Mysid Shrimp Larvae:

[0057] Feed the nursery ponds with processed shrimp flakes at a rate of 30g per million mysid shrimp larvae. Simultaneously, feed the nursery ponds with a mixture of processed rotifers and Artemia nauplii at a density of 5-6 rotifers / mL and 0.5-1 Artemia nauplii / mL. During the mysid shrimp larvae rearing period, add shrimp nursery water to the nursery ponds daily, controlling the amount of water added to 10% of the total water volume.

[0058] Step 6: Cultivation of shrimp larvae:

[0059] (1) Feed the nursery pond with processed shrimp flakes, 40g of shrimp flakes per million shrimp larvae, twice a day, morning and evening; and replace 20% of the water in the nursery pond with fresh water every day. The water temperature should be maintained at 30-31℃, and the nitrite content in the water should be less than 0.1mg / L and the total ammonium nitrogen content should be less than 0.3mg / L.

[0060] (2) During the rearing period of shrimp larvae, they need to be fed with processed Artemia nauplii; the feeding amount for shrimp larvae in the P1 stage is 10 million Artemia nauplii for every one million shrimp larvae, and then the feeding amount is increased by 10% every day; shrimp larvae can be hatched when they reach the P5~P10 stage, and the shrimp fry are transported long distances in oxygenated packages.

[0061] The treated rotifers are strengthened by using a rotifer strengthening material, and after strengthening for 12 hours, impurities and dead worms are separated to obtain the treated rotifers. The rotifer strengthening material includes Bacillus subtilis, Lactobacillus plantarum, Lactobacillus valerate, Lactobacillus rhamnosus, concentrated Nannochloropsis algae, concentrated deep-sea fish oil, and vitamin C. Each portion of the rotifer strengthening material can strengthen 100 million rotifers. Each portion of the rotifer strengthening material is prepared according to the ratio of 500 mL of Bacillus subtilis, 500 mL of Lactobacillus plantarum, 500 mL of Lactobacillus valerate, 500 mL of Lactobacillus rhamnosus, 800 mL of concentrated Nannochloropsis algae, 15 mL of concentrated deep-sea fish oil, and 30 g of vitamin C. The bacterial concentrations of Bacillus subtilis, Lactobacillus plantarum, Lactobacillus valerate, and Lactobacillus rhamnosus in the rotifer strengthening material are not less than 1×10 8 CFU / mL, the probiotics in the rotifer fortified material are convenient for shrimp fry to directly ingest, while regulating the intestinal microbial flora of shrimp, promoting the digestion and absorption of nutrients, inhibiting the growth of harmful bacteria such as Vibrio, and improving the quality of shrimp fry; the content of DHA and EPA in the nutritional composition of rotifers is lower than the nutritional requirement of shrimp larvae, so concentrated microgreens and concentrated deep-sea fish oil are added to the rotifer fortified material to increase the DHA and EPA content to strengthen the nutritional composition of rotifers, so as to improve the growth and metamorphosis rate of shrimp larvae.

[0062] The processed shrimp chips are shrimp microcapsule feeds, the shrimp chips are scrubbed with a 200-mesh mesh bag, and the liquid used for scrubbing is a probiotic solution, 10 L of probiotic solution I is used for every 100 g of shrimp chips, the shrimp chips after scrubbing are placed in a constant temperature culture room for fermentation, and the processed shrimp chips are obtained after fermentation for 5 to 6 hours, which can be fed to shrimp fry; the probiotic solution I includes Bacillus subtilis solution and Lactobacillus plantarum solution, the Bacillus subtilis solution and the Lactobacillus plantarum solution are uniformly mixed in equal proportions, and the bacterial content of the Bacillus subtilis solution and the Lactobacillus plantarum solution are 1×10 9 CFU / mL and 1×10 8CFU / mL; The fermented shrimp chips contain beneficial microorganisms, which are convenient for shrimp fry to directly ingest. While providing the necessary nutrition, they also regulate the intestinal microbial flora of shrimp, promote the digestion and absorption of nutrients, inhibit the growth of harmful bacteria such as Vibrio, and improve the quality of shrimp fry.

[0063] Treated Artemia nauplii, per 1m 3 80 million Artemia nauplii and probiotic solution II were added to the water in sequence. The invention discloses a method for preparing a probiotic solution of Artemia nauplii by mixing 400 mL of a mixture of Bacillus subtilis, Bacillus licheniformis, Lactobacillus rhamnosus, Lactobacillus plantarum, Pediococcus pentosaceus and Lactococcus lactis, wherein the probiotic solution II comprises Bacillus subtilis solution, Bacillus licheniformis, Lactobacillus rhamnosus, Lactobacillus plantarum, Pediococcus pentosaceus and Lactococcus lactis, and the Bacillus subtilis solution, Bacillus licheniformis, Lactobacillus rhamnosus, Lactobacillus plantarum, Pediococcus pentosaceus and Lactococcus lactis account for 25%, 25%, 12.5%, 12.5%, 12.5% ​​and 12.5% ​​of the total liquid volume, respectively. Artemia nauplii generally lack DHA, and feeding the fortified Artemia nauplii significantly improves the survival rate of shrimp larvae. The probiotic solution is convenient for shrimp fry to directly ingest, and at the same time regulates the intestinal microbial flora of shrimp, promotes the digestion and absorption of nutrients, inhibits the growth of harmful bacteria such as Vibrio, and improves the quality of shrimp fry.

[0064] In summary, the present invention has the following beneficial effects:

[0065] 1. By adding probiotics to the water in the nursery pond, the Vibrio in the water of the nursery pond is suppressed, and by feeding the shrimp fry with processed rotifers, shrimp flakes and Artemia nauplii, the Vibrio in the shrimp fry is suppressed, thereby improving the survival rate and quality of the shrimp fry;

[0066] 2. By adding DHA and other nutrients to the rotifers and Artemia nauplii, the nutrients required for the growth of shrimp fry can be met, thereby improving the quality of shrimp fry.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the design concept of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for raising Litopenaeus vannamei seedlings with synergistic enhancement of probiotics and nutrients, comprising the following steps: Step 1: Preparation of water for shrimp seedling cultivation: (1) The water used for shrimp seedling cultivation is natural seawater from the sea area adjacent to the shrimp seedling cultivation area. The natural seawater is preliminarily treated through sedimentation, sand filtration, and nitrification to make the water body of the natural seawater clear and transparent, thus obtaining first-class seedling cultivation water; (2) The salinity of the first-level seedling water is adjusted by concentration and desalination to control the salinity of the water at 29-30‰. Then, chlorine-containing disinfectant is added to the water, and the concentration is controlled at 25ppm. The disinfection time is controlled at 24h. The water is then aerated to make the water tumble. The aeration time is controlled at more than 10h. Finally, sodium thiosulfate solution is sprayed into the water to neutralize the residual chlorine in the water, thereby obtaining the second-level seedling water. (3) Sprinkle activated carbon powder into the secondary seedling water, and then evenly sprinkle disodium ethylenediaminetetraacetic acid (EDTA) into the water. Disodium ethylenediaminetetraacetic acid (EDTA) can chelate heavy metals such as lead, mercury, cadmium, chromium, and arsenic, and then obtain the tertiary seedling water; Step 2: Preparation of the nursery pond: (1) Use 100ppm chlorine-containing disinfectant to flush the nursery pond used for shrimp cultivation, then transfer the water used for shrimp cultivation to the nursery pond, control the water storage capacity at 60%, and then adjust the water temperature to 28~30℃ through the heating facilities of the nursery pond. At the same time, aerate the water in the nursery pond so that the water surface is slightly boiling; (2) Probiotics were added to the water in the nursery pond. The probiotics included Bacillus subtilis, Bacillus licheniformis and Lactobacillus plantarum, and the bacterial content in the water was set to 1×10 4 CFU / mL, 2×10 3 CFU / mL and 2×10 3 CFU / mL, 24 h after adding probiotics, nauplii were released; Step 3: Cultivation of nauplii: (1) Nauplii were released into the water of the nursery pond where probiotics had been added for more than 24 hours, with a density of 150,000 to 250,000 nauplii / mL, and then vitamin C powder was sprinkled into the water of the nursery pond; (2) After the nauplii were cultured for 40 hours, Chaetoceros was added to the water in the nursery pond, and the cell density was controlled at 300,000 to 400,000 cells / mL; Chaetoceros is a high-temperature resistant variety. (3) The nauplii in the nursery pond will metamorphose into zoeae within 48 hours. During the nauplii culture period, shrimp culture water should be added to the nursery pond every day, and the amount of shrimp culture water added should be controlled at 10% of the total water volume in the nursery pond. During the nauplii culture period, there is no need to add bait to the nursery pond. Nauplii use their own yolk as a nutrient source, so no external bait is needed. Step 4: Cultivation of zoeae; The development of zoeae to mysid larvae is divided into three cycles. When zoeae develop to stage I, they are fed with Chaetoceros algae in the nursery pond. When zoeae develop to stages II and III, they are fed with treated rotifers, with a feeding rate of 15 to 20 million Brachionus plicatilis for every one million zoeae. During the cultivation period of zoeae, shrimp nursery water is added to the nursery pond every day, and the amount of water added is controlled to be 10% of the total water volume in the nursery pond. Step 5: Cultivation of Mysid Shrimp Larvae: Feed the nursery ponds with processed shrimp flakes at a rate of 30g per million mysid shrimp larvae. Simultaneously, feed the nursery ponds with a mixture of processed rotifers and Artemia nauplii at a density of 5-6 rotifers / mL and 0.5-1 Artemia nauplii / mL. During the mysid shrimp larvae rearing period, add shrimp nursery water to the nursery ponds daily, controlling the amount of water added to 10% of the total water volume. Step 6: Cultivation of shrimp larvae: (1) Feed the nursery pond with processed shrimp flakes, 40g of shrimp flakes per million shrimp larvae, twice a day, morning and evening; and replace 20% of the water in the nursery pond with fresh water every day. The water temperature should be maintained at 30-31℃, and the nitrite content in the water should be less than 0.1mg / L and the total ammonium nitrogen content should be less than 0.3mg / L. (2) During the cultivation period of shrimp larvae, they need to be fed with processed Artemia nauplii. The feeding amount for shrimp larvae at the P1 stage is 10 million Artemia nauplii per million shrimp larvae, and then the feeding amount is increased by 10% every day. Shrimp larvae can be hatched when they reach the P5~P10 stage, and the shrimp fry are transported long distances in oxygenated packages. The treated rotifers are strengthened by using a rotifer strengthening material, and after strengthening for 12 hours, impurities and dead worms are separated to obtain the treated rotifers, wherein the rotifer strengthening material includes Bacillus subtilis, Lactobacillus plantarum, Lactobacillus valerate, Lactobacillus rhamnosus, concentrated Nannochloropsis algae, concentrated deep-sea fish oil, and vitamin C; The treated shrimp chips are shrimp microcapsule feeds, the shrimp chips are scrubbed with a 200-mesh mesh bag, and the liquid used during scrubbing is a probiotic liquid I, 10L of probiotic liquid I is used for every 100g of shrimp chips, the shrimp chips after scrubbing are placed in a constant temperature culture chamber for fermentation, and the treated shrimp chips are obtained after fermentation for 5-6h, wherein the probiotic liquid I includes a Bacillus subtilis liquid and a Lactobacillus plantarum liquid, and the Bacillus subtilis liquid and the Lactobacillus plantarum liquid are evenly mixed in equal proportions; The treated Artemia nauplii, per 1m 3 80 million Artemia nauplii, 400 mL of probiotic liquid II, 50 g of DHA enhancer, 30 g of astaxanthin, 10 g of multivitamins and 10 g of polysaccharide are sequentially added into the water body to obtain treated Artemia nauplii. The probiotic liquid II includes Bacillus subtilis liquid, Bacillus licheniformis, Lactobacillus rhamnosus, Lactobacillus plantarum, Pediococcus pentosaceus and Lactococcus lactis.

2. The method for raising Litopenaeus vannamei seedlings with synergistic enhancement of probiotics and nutrients according to claim 1, characterized in that: The rotifer fortification material is prepared by mixing 500 mL of Bacillus subtilis, 500 mL of Lactobacillus plantarum, 500 mL of Lactobacillus valerate, 500 mL of Lactobacillus rhamnosus, 800 mL of concentrated Nannochloropsis algae, 15 mL of concentrated deep-sea fish oil, and 30 g of vitamin C. Each portion of the rotifer fortification material can be used to fortify 100 million rotifers, and the bacterial concentrations of Bacillus subtilis, Lactobacillus plantarum, Lactobacillus valerate, and Lactobacillus rhamnosus in the rotifer fortification material are not less than 10 8 CFU / mL.

3. The method for raising Litopenaeus vannamei seedlings with synergistic enhancement of probiotics and nutrients according to claim 1, characterized in that: The bacterial contents in the Bacillus subtilis solution and the Lactobacillus plantarum solution were 1×10 9 CFU / mL and 1×10 8 CFU / mL.

4. The method for raising Litopenaeus vannamei seedlings with synergistic enhancement of probiotics and nutrients according to claim 1, characterized in that: The Bacillus subtilis liquid, Bacillus licheniformis, Lactobacillus rhamnosus, Lactobacillus plantarum, Pediococcus pentosaceus and Lactococcus lactis account for 25%, 25%, 12.5%, 12.5%, 12.5% ​​and 12.5% ​​of the total liquid respectively.