Feed for culturing grouper after disaster as well as preparation method and application of feed

Abstract

The invention provides a feed for culturing groupers after disasters as well as a preparation method and application of the feed, and belongs to the technical field of grouper culture feeds. The feed comprises 10-20 parts of hermetia illucens larva powder, 35-45 parts of fish meal, 8-12 parts of soybean protein concentrate, 3-6 parts of casein, 14-16 parts of wheat flour, 2-4 parts of an adhesive, 1-2 parts of monocalcium phosphate, 2-3 parts of shrimp meal, 1-3 parts of soybean oil, 1-3 parts of fish oil, 1-2 parts of cuttlefish paste, 0.5-1.5 parts of a vitamin premix and 0.5-1.5 parts of a mineral premix. The feed is balanced in nutrition, can remarkably promote growth of the grouper after disasters and improve the oxidation resistance, does not cause death of the grouper after disasters, and effectively relieves stress response of the grouper after disasters. The feed is green and environment-friendly, the dependence on marine resources is reduced, the pollution of a culture water body can be reduced, and the culture environment is improved. The preparation method disclosed by the invention is simple, convenient and feasible and is suitable for industrial production.

Description

Technical Field

[0001] The invention belongs to the technical field of grouper breeding feed, and in particular relates to a feed for breeding post-disaster grouper and a preparation method and application thereof. Background Art

[0002] Grouper is a medium-sized warm-water marine fish, widely distributed in tropical and subtropical waters. It has a high market value due to its rapid growth, rich nutrition, and good meat quality, and has gradually become one of the important marine aquaculture targets. Grouper has a high nutritional demand for feed. With the expansion of aquaculture, it is more important to find alternative feed or cheap feed.

[0003] Traditional grouper farming is a shallow-water cage farming method that is highly dependent on the coastal natural environment and climate. When natural disasters occur, such as typhoons, red tides or cold currents, it is easy to cause a reduction in grouper production or even a total loss. Hainan generally has 6 to 10 typhoons every year, and Hainan is one of the main areas of typhoon activity in the world. Its activities are characterized by high frequency, high intensity and long activity time. The active period is from June to November every year. After the typhoon, in addition to the damage to the pond / high-level pond embankment slope, seaward sand filter well, aeration equipment, and the roof of the breeding shed, the grouper farms will also die in large numbers due to power outages, lack of oxygen, and a sudden drop in salinity. Therefore, providing green and environmentally friendly compound feed to meet the survival and growth needs of groupers, especially groupers after disasters, is also a technical problem that needs to be solved at present. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a feed for breeding post-disaster grouper and a preparation method and application thereof, wherein the feed can promote the growth of post-disaster grouper, improve the antioxidant capacity and survival rate of post-disaster grouper, thereby effectively alleviating the stress response of post-disaster grouper.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The present invention provides a feed for breeding post-disaster grouper, comprising the following raw materials in parts by weight: 10-20 parts of black soldier fly larvae powder, 35-45 parts of fish meal, 8-12 parts of concentrated soy protein, 3-6 parts of casein, 14-16 parts of wheat flour, 2-4 parts of adhesive, 1-2 parts of monocalcium phosphate, 2-3 parts of shrimp meal, 1-3 parts of soybean oil, 1-3 parts of fish oil, 1-2 parts of squid paste, 0.5-1.5 parts of vitamin premix and 0.5-1.5 parts of mineral premix.

[0006] Preferably, the feed further comprises 0.01-0.06 parts of vitamin C and 0.2-1.4 parts of taurine; and the adhesive comprises polyadhesive.

[0007] Preferably, the black soldier fly larvae powder is obtained by crushing 6th-instar black soldier fly larvae and passing through a 50-70 mesh sieve.

[0008] Preferably, the method for preparing the 6-instar black soldier fly larvae comprises inoculating 4-6 day old black soldier fly larvae in a culture medium and culturing them for 8-10 days.

[0009] Preferably, the method for preparing the culture medium comprises separating the solid and liquid of the solid waste from the aquaculture farm, collecting the solid matter and drying it to obtain dry solid waste; mixing the dry solid waste, wheat bran and dried dead fish in a mass ratio of (4-6): (1-3): (2-4), crushing and sieving to obtain a mixture, and mixing the mixture with EM bacterial solution for sealed fermentation to obtain the culture medium.

[0010] Preferably, the mesh size of the sieving is 20-40 mesh; the mass ratio of the mixture to the EM bacterial solution is 250-350:2.5-3.5; the fermentation temperature is 20-35°C, and the fermentation time is 10-16 days; and the inoculation density is 1400-1600 per kilogram of culture medium.

[0011] The present invention also provides a method for preparing the above feed, comprising the following steps: (1) grinding and sieving the fish meal, soy protein concentrate and wheat flour to obtain a mixture 1; (2) mixing the mixture 1, black soldier fly larvae powder, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix and mineral premix to obtain a mixture 2; or mixing the mixture 1, black soldier fly larvae powder, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine to obtain a mixture 2a; (3) Mixing the mixed material II, the soybean oil, the fish oil, the squid paste, the binder and water, granulating and drying to obtain a feed for breeding post-disaster grouper; The mixture II is mixture 2 or mixture 2a.

[0012] Preferably, in step (1), the mesh size of the sieve is 50-70 mesh; In step (3), the amount of water added is 20-30 mL, the drying temperature is 20-30° C., and the drying time is 46-50 h; The feed is cylindrical feed particles with a diameter of 3.00 mm and a length of 4 to 5 cm.

[0013] The present invention also provides a use of the above feed or the feed prepared by the preparation method in at least one of the following a to d: a. Raising grouper with breeding agents after the disaster; b. preparing a growth promoter for grouper after disaster; c. Improve the antioxidant capacity and / or survival rate of grouper after disasters; d. Prepare an agent to alleviate the stress response of grouper after a disaster.

[0014] Preferably, the post-disaster grouper is a grouper caught after a typhoon.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a feed for breeding post-disaster grouper and a preparation method and application thereof. The feed is nutritionally balanced and can meet the growth requirements of post-disaster grouper. Studies have shown that feeding the feed of the present invention to post-disaster grouper can significantly promote the growth of post-disaster grouper, improve antioxidant capacity, and no post-disaster grouper death occurs, indicating that the post-disaster grouper stress response is effectively alleviated. The feed of the present invention is green and environmentally friendly, reduces dependence on marine resources, and can also reduce the pollution of aquaculture water bodies and improve the aquaculture environment.

[0016] The preparation method of the feed for breeding post-disaster grouper of the present invention is simple and easy to implement, and is suitable for industrial production. The present invention provides a new idea and choice for breeding feed for post-disaster grouper. DETAILED DESCRIPTION

[0017] The present invention provides a feed for breeding post-disaster grouper, comprising the following raw materials in parts by weight: 10-20 parts of black soldier fly larvae powder, 35-45 parts of fish meal, 8-12 parts of concentrated soy protein, 3-6 parts of casein, 14-16 parts of wheat flour, 2-4 parts of adhesive, 1-2 parts of monocalcium phosphate, 2-3 parts of shrimp meal, 1-3 parts of soybean oil, 1-3 parts of fish oil, 1-2 parts of squid paste, 0.5-1.5 parts of vitamin premix and 0.5-1.5 parts of mineral premix.

[0018] In the above feed, the black soldier fly larvae powder is obtained by crushing 6-year-old black soldier fly larvae and passing through a 50-70 mesh sieve. The mesh sieve is further a 55-65 mesh sieve, more preferably a 60 mesh sieve. The preparation method of the 6-year-old black soldier fly larvae of the present invention comprises inoculating 4-6 day-old black soldier fly larvae in a culture medium and culturing for 8-10 days. The preparation method of the culture medium comprises separating solid and liquid from solid waste from an aquaculture farm, collecting solid matter and drying it to obtain dry solid waste; mixing the dry solid waste, wheat bran and dried dead fish in a mass ratio of (4-6): (1-3): (2-4), crushing, sieving, obtaining a mixture, mixing the mixture with EM bacterial liquid and sealing for fermentation, and obtaining the mixture. The solid waste includes wastes such as residual bait, fish metabolic byproducts or feces. Fish metabolic byproducts mainly refer to non-main products produced during fish processing, and these byproducts include bones, skin, internal organs, scales, etc. The mesh number of the sieve is 20-40 mesh, and the mesh number is further preferably 25-35 mesh, and more preferably 30 mesh; the mass ratio of the mixture to the EM bacterial liquid is 250-350:2.5-3.5; the fermentation temperature is 20-35°C, and the fermentation time is 10-16d, and more preferably 12-15d. The EM bacteria selected in the present invention are a mixed bacteria, including photosynthetic bacteria, yeast, lactic acid bacteria and other beneficial bacteria, which have the function of fermenting and decomposing organic matter in feed and providing efficient metabolic nutritional components. Black soldier flies have weak processing ability for organic macromolecular substrates and strong processing ability for small molecular carbohydrates. The present invention can decompose and utilize the organic matter in the above-mentioned solid waste, wheat bran and dried dead fish through EM bacterial liquid to complete its own growth and reproduction, and at the same time produce a large amount of proteases, amylases and cellulases, etc., and degrade the macromolecular nutrients (such as protein, starch and cellulose, etc.) into small molecular substances that are easily digested by the intestines. Therefore, the culture medium obtained by fermentation ensures the nutrients required by black soldier flies larvae. The inoculation density is 1400-1600 per kilogram of culture medium, more preferably 1450-1550, such as 1500. The present invention not only effectively utilizes the solid waste of aquaculture farms, but also promotes the growth of black soldier fly larvae by feeding the culture medium to black soldier fly larvae, and the obtained 6-year-old black soldier fly larvae have high crude protein and crude fat contents.

[0019] In the above feed, the study found that when the weight of black soldier fly larvae powder is 10 to 20 parts, more preferably 12 to 18 parts, and more preferably 15 parts, it can promote the growth of grouper. The black soldier fly larvae powder of the present invention is a sustainable substitute for fish meal in aquatic feed. The production cost of black soldier fly larvae is lower than that of fish meal, providing a more economical alternative. In addition, black soldier flies grow fast and can reproduce in large numbers in a smaller space, reducing dependence on marine resources. The feed of the present invention uses black soldier fly larvae powder as a raw material, reducing the addition of relatively expensive fish meal, thereby reducing the cost of the feed.

[0020] In the above feed, the fish meal is a high-protein feed raw material made from one or more fish species, which is processed by degreasing, dehydration and pulverization, and is a product made from whole wild fish, by-catch and fish by-products. The weight of the fish meal is further preferably 37 to 42 parts, more preferably 38 to 41 parts, such as 40 parts. The present invention has no special limitation on the source of the fish meal, and commercially available products in the art can be used, such as the fish meal sold by Guangzhou Rifeng Biotechnology Co., Ltd.

[0021] In the above feed, the weight portion of the soy protein concentrate is further preferably 9-11 parts, more preferably 10 parts; the weight portion of the casein is further preferably 4-5 parts, more preferably 5 parts; the weight portion of wheat flour is further preferably 14.2-15.5 parts, more preferably 15.5, 15.24, 14.98, 14.72, 14.46 or 14.20 parts; the weight portion of the adhesive is further preferably 2.5-3.5 parts, more preferably 3 parts, and the adhesive is polynianbao; the weight portion of calcium dihydrogen phosphate is further preferably 1.2-1.6 parts, more preferably 1.5 parts; the weight portion of the shrimp meal is further preferably 2.2-2.8 parts, more preferably 2.5 parts, and the main raw material of the shrimp meal is dried shrimp, which is ground into powder after drying. The weight portion of soybean oil is more preferably 1.5-2.5 parts, more preferably 2 parts; the weight portion of fish oil is more preferably 1.5-2.5 parts, more preferably 2 parts; the weight portion of cuttlefish paste is more preferably 1.2-1.8 parts, more preferably 1.5 parts; the weight portion of vitamin premix is ​​more preferably 0.7-1.3 parts, more preferably 1 part; the weight portion of mineral premix is ​​more preferably 0.7-1.3 parts, more preferably 1 part. The present invention does not specifically limit the sources of fish meal, soybean protein concentrate, casein, wheat flour, adhesive, calcium dihydrogen phosphate, shrimp meal, soybean oil, fish oil, cuttlefish paste, vitamin premix and mineral premix, and commercial products known in the art can be used.

[0022] In the above feed, the feed also includes 0.01-0.06 parts of vitamin C and 0.2-1.4 parts of taurine. Studies have found that the present invention can effectively promote the growth of post-disaster grouper, improve the antioxidant capacity of grouper, prevent post-disaster grouper mortality, and improve the stress response of post-disaster grouper by adding vitamins and taurine to the feed.

[0023] The present invention also provides a method for preparing the above feed, comprising the following steps: (1) grinding and sieving the fish meal, soy protein concentrate and wheat flour to obtain a mixture 1; (2) mixing the mixture 1, black soldier fly larvae powder, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix and mineral premix to obtain a mixture 2; or mixing the mixture 1, black soldier fly larvae powder, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine to obtain a mixture 2a; (3) Mixing the mixed material II, the soybean oil, the fish oil, the squid paste, the binder and water, granulating and drying to obtain a feed for breeding post-disaster grouper; The mixture II is mixture 2 or mixture 2a.

[0024] In the above step (1), the mesh size of the sieve is 50-70 mesh, preferably 55-65 mesh, and more preferably 60 mesh. In the above step (2), the mixing method is not particularly limited, and manual or instrument stirring can be used. In the above step (3), the amount of water added is preferably 20-30 mL, more preferably 22-28 mL, and more preferably 25 mL; the drying temperature is 20-30°C, more preferably 22-28°C, more preferably 23-26°C, such as 25°C. The drying time is preferably 46-50 h, more preferably 47-48 h, such as 48 h. The feed obtained by granulation of the present invention is a cylindrical feed pellet with a diameter of 3.00 mm and a length of 4-5 cm, and more preferably a cylindrical feed pellet with a diameter of 3.00 mm and a length of 4.5 cm. The cylindrical feed pellets prepared by the present invention make it easier for post-disaster grouper to eat in water, and are not easy to pollute the aquaculture water body, thereby improving the aquaculture environment.

[0025] The present invention also provides a use of the above feed or the feed prepared by the preparation method in at least one of the following a to d: a. Raising grouper with breeding agents after the disaster; b. preparing a growth promoter for grouper after disaster; c. Improve the antioxidant capacity and / or survival rate of grouper after disasters; d. Prepare an agent to alleviate the stress response of grouper after a disaster.

[0026] In the present invention, the post-disaster grouper is the grouper after a typhoon.

[0027] In the present invention, unless otherwise specified, all raw material components are commercially available products well known to those skilled in the art.

[0028] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0029] In the following examples, black soldier fly larvae (newly hatched larvae) were purchased from Guangzhou Feixite Biotechnology Co., Ltd.; fish meal, soybean protein concentrate, shrimp meal, calcium dihydrogen phosphate, vitamin premix and mineral premix were all purchased from Guangzhou Rifeng Biotechnology Co., Ltd.; fish oil was purchased from Guangzhou Chenyang Biotechnology Co., Ltd.; soybean oil used was soybean oil from Jinlongyu; the adhesive used was Huzhou Jingbao Feed Additive Co., Ltd. (Ju Nianbao); and EM bacterial liquid was purchased from Liyang Aquatic Products Technology Co., Ltd.

[0030] Example 1 A method for preparing black soldier fly larvae powder, comprising the following steps: (1) Plastic trays were used as feeding apparatus, with fish meal and wheat bran as the main feed. The temperature of the feed in the trays was kept at 30-32°C, the relative humidity (RH) of the environment was not less than 60%, and the humidity in the trays was not more than 70%. A protective net was added to the trays, and the feed was changed every 24 hours. The development period from newly hatched larvae to 1st instar larvae was about 4-6 days. The 1st instar larvae were uniform in size, milky white in color, healthy and lively, i.e. 4-6 day-old (1st instar) black soldier fly larvae.

[0031] (2) After the typhoon, the solid wastes including residual bait, fish metabolic byproducts, feces, etc. in the aquaculture farm are separated from the solid and liquid, and the solids are dried to obtain dry solid waste. The dry solid waste, wheat bran and dried dead fish after the disaster are mixed evenly according to the dry weight ratio of 5:2:3, and then crushed and sieved through 30 mesh to obtain a mixture. Take 300g of the mixture, spray 3g of EM bacterial solution evenly, and ferment it at 28℃ for 12~15d. After that, fill it evenly into a plastic material tray with a length, width and height of 40cm, 40cm and 10cm respectively. The water content requirement is 65~70%. After obtaining the culture medium, inoculate the 4~6-day-old (1st-age) black soldier fly larvae obtained in step (1) at an inoculation density of 1500 per kilogram of culture medium. Raise it for 8~10 days until half of the larvae pre-pupae, that is, obtain 6-age black soldier fly larvae.

[0032] The dry matter reduction rate of the mixture reached 43.60%, and the insect body yield reached 14.60% (g / g-dry matter consumption).

[0033] (3) The 6th-instar black soldier fly larvae are crushed and passed through a 60-mesh net to obtain black soldier fly larvae powder.

[0034] The obtained black soldier fly larvae powder was tested for crude protein, crude fat, crude ash and moisture content, and the percentages of crude protein, crude fat, crude ash and moisture content in the total dry matter of the black soldier fly larvae powder were counted. The results are shown in Table 1.

[0035] Table 1 Nutritional composition test results of black soldier fly larvae powder

[0036] The results in Table 1 show that among the nutritional components of black soldier fly larvae meal, the contents of crude protein and crude fat are high.

[0037] Example 2 A feed for breeding post-disaster grouper, composed of the following raw materials by weight: 15g of black soldier fly larvae powder prepared in Example 1, 40g of fish meal, 10g of concentrated soybean protein, 5g of casein, 15.5g of wheat flour, 3g of adhesive, 1.5g of monocalcium phosphate, 2.5g of shrimp meal, 2g of soybean oil, 2g of fish oil, 1.5g of squid paste, 1g of vitamin premix and 1g of mineral premix.

[0038] The method for preparing feed for breeding post-disaster grouper comprises the following steps: (1) grinding the fish meal, soybean protein concentrate and wheat flour in a powder mill and passing through a 60-mesh screen to obtain a mixture 1; (2) Mixture 1, the black soldier fly larvae powder prepared in Example 1, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix and mineral premix were placed in a U-shaped double-screw ribbon mixer (WLDH-30, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) for mixing to obtain mixture 2; (3) Mixture 2, soybean oil, fish oil, squid paste, and adhesive were mixed with 25 mL of water and a twin-screw extruder (F-75, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) and a granulator (G-500, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) were used to produce cylindrical feed pellets with a diameter of 3.00 mm and a length of 4.5 cm. The pellets were then dried at 25 °C for 48 h to obtain feed for post-disaster grouper farming, which was then stored at -20 °C for later use.

[0039] Example 3 A feed for breeding post-disaster grouper, comprising the following raw materials by weight: 15 g of black soldier fly larvae powder prepared in Example 1, 40 g of fish meal, 10 g of concentrated soybean protein, 5 g of casein, 15.24 g of wheat flour, 3 g of adhesive, 1.5 g of monocalcium phosphate, 2.5 g of shrimp meal, 2 g of soybean oil, 2 g of fish oil, 1.5 g of squid paste, 1 g of vitamin premix, 1 g of mineral premix, 0.01 g of vitamin C and 0.25 g of taurine.

[0040] The method for preparing feed for breeding post-disaster grouper comprises the following steps: (1) grinding the fish meal, soybean protein concentrate and wheat flour in a powder mill and passing through a 60-mesh screen to obtain a mixture 1; (2) The mixture 1, the black soldier fly larvae powder prepared in Example 1, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine were placed in a U-shaped double-screw ribbon mixer (WLDH-30, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) for mixing to obtain a mixture 2a; (3) Mixture 2a, soybean oil, fish oil, squid paste, and adhesive were mixed with 25 mL of water and a twin-screw extruder (F-75, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) and a granulator (G-500, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) were used to produce cylindrical feed pellets with a diameter of 3.00 mm and a length of 4.5 cm. The pellets were then dried at 25 °C for 48 h to obtain feed for post-disaster grouper farming, which was then stored at -20 °C for later use.

[0041] Example 4 A feed for breeding post-disaster grouper, comprising the following raw materials by weight: 15 g of black soldier fly larvae powder prepared in Example 1, 40 g of fish meal, 10 g of concentrated soybean protein, 5 g of casein, 14.98 g of wheat flour, 3 g of adhesive, 1.5 g of monocalcium phosphate, 2.5 g of shrimp meal, 2 g of soybean oil, 2 g of fish oil, 1.5 g of squid paste, 1 g of vitamin premix, 1 g of mineral premix, 0.02 g of vitamin C and 0.5 g of taurine.

[0042] The method for preparing feed for breeding post-disaster grouper comprises the following steps: (1) grinding the fish meal, soybean protein concentrate and wheat flour in a powder mill and passing through a 60-mesh screen to obtain a mixture 1; (2) The mixture 1, the black soldier fly larvae powder prepared in Example 1, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine were placed in a U-shaped double-screw ribbon mixer (WLDH-30, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) for mixing to obtain a mixture 2a; (3) Mixture 2a, soybean oil, fish oil, squid paste, and adhesive were mixed with 25 mL of water and a twin-screw extruder (F-75, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) and a granulator (G-500, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) were used to produce cylindrical feed pellets with a diameter of 3.00 mm and a length of 4.5 cm. The pellets were then dried at 25 °C for 48 h to obtain feed for post-disaster grouper farming, which was then stored at -20 °C for later use.

[0043] Example 5 A feed for breeding post-disaster grouper, comprising the following raw materials by weight: 15 g of black soldier fly larvae powder prepared in Example 1, 40 g of fish meal, 10 g of concentrated soybean protein, 5 g of casein, 14.72 g of wheat flour, 3 g of adhesive, 1.5 g of monocalcium phosphate, 2.5 g of shrimp meal, 2 g of soybean oil, 2 g of fish oil, 1.5 g of squid paste, 1 g of vitamin premix, 1 g of mineral premix, 0.03 g of vitamin C and 0.75 g of taurine.

[0044] The method for preparing feed for breeding post-disaster grouper comprises the following steps: (1) grinding the fish meal, soybean protein concentrate and wheat flour in a powder mill and passing through a 60-mesh screen to obtain a mixture 1; (2) The mixture 1, the black soldier fly larvae powder prepared in Example 1, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine were placed in a U-shaped double-screw ribbon mixer (WLDH-30, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) for mixing to obtain a mixture 2a; (3) Mixture 2a, soybean oil, fish oil, squid paste, and adhesive were mixed with 25 mL of water and a twin-screw extruder (F-75, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) and a granulator (G-500, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) were used to produce cylindrical feed pellets with a diameter of 3.00 mm and a length of 4.5 cm. The pellets were then dried at 25 °C for 48 h to obtain feed for post-disaster grouper farming, which was then stored at -20 °C for later use.

[0045] Example 6 A feed for breeding post-disaster grouper, comprising the following raw materials by weight: 15g of black soldier fly larvae powder prepared in Example 1, 40g of fish meal, 10g of concentrated soybean protein, 5g of casein, 14.46g of wheat flour, 3g of adhesive, 1.5g of monocalcium phosphate, 2.5g of shrimp meal, 2g of soybean oil, 2g of fish oil, 1.5g of squid paste, 1g of vitamin premix, 1g of mineral premix, 0.04g of vitamin C and 1g of taurine.

[0046] The method for preparing feed for breeding post-disaster grouper comprises the following steps: (1) grinding the fish meal, soybean protein concentrate and wheat flour in a powder mill and passing through a 60-mesh screen to obtain a mixture 1; (2) The mixture 1, the black soldier fly larvae powder prepared in Example 1, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine were placed in a U-shaped double-screw ribbon mixer (WLDH-30, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) for mixing to obtain a mixture 2a; (3) Mixture 2a, soybean oil, fish oil, squid paste, and adhesive were mixed with 25 mL of water and a twin-screw extruder (F-75, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) and a granulator (G-500, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) were used to produce cylindrical feed pellets with a diameter of 3.00 mm and a length of 4.5 cm. The pellets were then dried at 25 °C for 48 h to obtain feed for post-disaster grouper farming, which was then stored at -20 °C for later use.

[0047] Example 7 A feed for breeding post-disaster grouper, comprising the following raw materials by weight: 15 g of black soldier fly larvae powder prepared in Example 1, 40 g of fish meal, 10 g of concentrated soybean protein, 5 g of casein, 14.20 g of wheat flour, 3 g of adhesive, 1.5 g of monocalcium phosphate, 2.5 g of shrimp meal, 2 g of soybean oil, 2 g of fish oil, 1.5 g of squid paste, 1 g of vitamin premix, 1 g of mineral premix, 0.05 g of vitamin C and 1.25 g of taurine.

[0048] The method for preparing feed for breeding post-disaster grouper comprises the following steps: (1) grinding the fish meal, soybean protein concentrate and wheat flour in a powder mill and passing through a 60-mesh screen to obtain a mixture 1; (2) The mixture 1, the black soldier fly larvae powder prepared in Example 1, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine were placed in a U-shaped double-screw ribbon mixer (WLDH-30, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) for mixing to obtain a mixture 2a; (3) Mixture 2a, soybean oil, fish oil, squid paste, and adhesive were mixed with 25 mL of water and a twin-screw extruder (F-75, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) and a granulator (G-500, Guangzhou Huagong Optoelectronics Co., Ltd., Guangzhou, China) were used to produce cylindrical feed pellets with a diameter of 3.00 mm and a length of 4.5 cm. The pellets were then dried at 25 °C for 48 h to obtain feed for post-disaster grouper farming, which was then stored at -20 °C for later use.

[0049] Test Example 1 Effects of feeds for breeding post-disaster grouper prepared in Examples 2 to 7 on growth performance and antioxidant capacity of post-disaster grouper The grouper used in the experiment was purchased from a severely affected grouper farm in Danzhou, Hainan. Before the start of the breeding experiment, all the groupers were not eating after the typhoon and were in a depressed state. At this time, the water and electricity were cut off. One week after the typhoon, the surviving groupers were fed twice a day at 08:00 and 16:00. At the beginning of the experiment, all experimental fish fasted for 24 hours. 540 groupers with an initial average weight of about 18g were selected and randomly distributed into 18 500L fiberglass barrels (400L of water in each barrel), 30 per barrel, and three replicates were set for each group. The feed for breeding post-disaster groupers prepared in Examples 2 to 7 was fed at 08:00 and 16:00 every day, and the breeding time was 6 weeks. 80 to 120L of water was changed in each breeding barrel every day. During the breeding experiment, the pH value of the breeding water was 6.8~7.25, the temperature was 28~32°C, the dissolved oxygen concentration was greater than 6.0 mg / L, the salinity was 29~31‰, and the ammonia nitrogen concentration did not exceed 0.05 mg / L.

[0050] Through a 42-day breeding experiment, the initial body weight of grouper in each group and the body weight (final weight) of grouper after feeding were recorded. At the same time, the number of surviving grouper after feeding was recorded, and the relevant indicators of grouper growth performance were determined: SR (survival rate), WGR (weight gain rate), CF (fatness) were affected by the levels of taurine and VC in the feed.

[0051] Among them, SR (survival rate) = the number of surviving groupers after feeding ÷ 30 × 100%.

[0052] WGR (weight gain rate) = (final weight of grouper after feeding - initial weight of grouper) ÷ initial weight of grouper × 100%.

[0053] CF (fatness) = 100 × [fish weight (g) / body length 3 (cm 3 )].

[0054] Table 2 Results of the effects of feeds used in Examples 2 to 7 on the growth performance of post-disaster grouper

[0055] Note: Different letters in the table indicate significant differences among different groups.

[0056] The results in Table 2 show that the addition of taurine and vitamin C to the feed has a significant growth-promoting effect. When taurine and vitamin C are deficient, grouper shows relatively poor growth performance. WGR first increases and then decreases with the increase of taurine level. When the taurine level is 1g and the vitamin C level is 0.04g, that is, when the feed of the farmed post-disaster grouper of Example 6 is fed, the growth-promoting degree is the highest. Therefore, the feed of the farmed post-disaster grouper of Example 6 has a more obvious growth-promoting effect on grouper.

[0057] The superoxide dismutase SOD activity, catalase CAT, total antioxidant capacity T-AOC, glutathione peroxidase GSH-Px activity and malondialdehyde MDA content in the serum of grouper after feeding with each group of feed were detected.

[0058] Table 3 Results of the antioxidant capacity of the feeds for breeding post-disaster grouper in Examples 2 to 7 on post-disaster grouper

[0059] Note: Different letters in the table indicate significant differences among different groups.

[0060] The results in Table 3 show that adding different levels of taurine and vitamin C to the feed can significantly increase the activities of the main antioxidant enzymes in the serum: SOD, CAT, GSH-Px and T-AOC, and significantly reduce the MDA content. This is consistent with the results of the growth performance experiment. Therefore, the addition of 1g of taurine and 0.04g of vitamin C in the feed, that is, the feed for feeding the post-disaster grouper in Example 6, is most conducive to the growth of grouper, antioxidant capacity and immune stress capacity.

[0061] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A feed for breeding post-disaster grouper, characterized in that: The invention comprises the following raw materials in parts by weight: 10-20 parts of black soldier fly larvae powder, 35-45 parts of fish meal, 8-12 parts of concentrated soy protein, 3-6 parts of casein, 14-16 parts of wheat flour, 2-4 parts of adhesive, 1-2 parts of monocalcium phosphate, 2-3 parts of shrimp meal, 1-3 parts of soybean oil, 1-3 parts of fish oil, 1-2 parts of squid paste, 0.5-1.5 parts of vitamin premix and 0.5-1.5 parts of mineral premix.

2. The feed according to claim 1, characterized in that The feed also includes 0.01-0.06 parts of vitamin C and 0.2-1.4 parts of taurine; and the adhesive includes polyadhesive.

3. The feed according to claim 1, characterized in that The black soldier fly larvae powder is obtained by crushing 6th-instar black soldier fly larvae and passing through a 50-70 mesh sieve.

4. The feed according to claim 3, characterized in that The preparation method of the 6-instar black soldier fly larvae comprises inoculating 4-6 day-old black soldier fly larvae into a culture medium and culturing for 8-10 days.

5. The feed according to claim 4, characterized in that The preparation method of the culture medium comprises the following steps: performing solid-liquid separation on solid waste from an aquaculture farm, collecting solid matter and then drying it to obtain dry solid waste; mixing the dry solid waste, wheat bran and dried dead fish in a mass ratio of (4-6): (1-3): (2-4), crushing and sieving to obtain a mixture, and mixing the mixture with EM bacterial liquid for sealed fermentation to obtain the culture medium.

6. The feed according to claim 5, characterized in that The mesh number of the sieving is 20-40 meshes; the mass ratio of the mixture to the EM bacterial solution is 250-350:2.5-3.5; the fermentation temperature is 20-35°C, and the fermentation time is 10-16 days; the inoculation density is 1400-1600 per kilogram of culture medium.

7. A method for preparing the feed according to any one of claims 1 to 6, characterized in that: The following steps are involved: (1) grinding and sieving the fish meal, soy protein concentrate and wheat flour to obtain a mixture 1; (2) mixing the mixture 1, black soldier fly larvae powder, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix and mineral premix to obtain a mixture 2; or mixing the mixture 1, black soldier fly larvae powder, casein, calcium dihydrogen phosphate, shrimp meal, vitamin premix, mineral premix, vitamin C and taurine to obtain a mixture 2a; (3) Mixing the mixed material II, the soybean oil, the fish oil, the squid paste, the binder and water, granulating and drying to obtain a feed for breeding post-disaster grouper; The mixture II is mixture 2 or mixture 2a.

8. The preparation method according to claim 7, characterized in that: In step (1), the mesh size of the sieving is 50-70 mesh; In step (3), the amount of water added is 20-30 mL, the drying temperature is 20-30° C., and the drying time is 46-50 h; The feed is cylindrical feed particles with a diameter of 3.00 mm and a length of 4 to 5 cm.

9. Use of the feed according to any one of claims 1 to 6 or the feed prepared by the preparation method according to claim 7 or 8 in at least one of the following a to d: a. Raising grouper with breeding agents after the disaster; b. preparing a growth promoter for grouper after disaster; c. Improve the antioxidant capacity and / or survival rate of grouper after disasters; d. Prepare an agent to alleviate the stress response of grouper after a disaster.

10. The use according to claim 9, characterized in that: The post-disaster grouper is the grouper after the typhoon.

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