A compound feed for Chinese sturgeon fry and a preparation method thereof

Abstract

The application provides a compound feed for Chinese sturgeon fry and a preparation method thereof. The compound feed according to the application comprises, in terms of mass percentage, 20-40% of fish meal, 0-20% of cottonseed protein concentrate, 10-30% of soybean protein concentrate, 12-18% of flour, 2-6% of blood globule powder, 0.5-2% of calcium dihydrogen phosphate, 0.2-0.8% of choline chloride, 1-2% of phospholipid oil, 2-5% of fish oil, 2-4% of soybean oil, 0.5-1% of compound vitamin, 0.5-1% of compound mineral, 0-6% of glutamic acid and 0-10% of microcrystalline cellulose. The compound feed can increase the weight gain rate and specific growth rate of Chinese sturgeon fry, thereby promoting the growth of Chinese sturgeon fry, and can also reduce the use amount of fish meal and the feed conversion ratio, thereby reducing the production and breeding cost.

Description

Technical Field

[0001] This invention relates to the field of artificial breeding technology for rare fish, and in particular to a compound feed for juvenile and young Chinese sturgeon and its preparation method. Background Technology

[0002] In 1988, the Chinese sturgeon (Acipenser sinensis) was listed as a Class I protected species in the National Key Protected Wild Animals List. To date, relevant release units have released approximately 8 million Chinese sturgeon, which is far from sufficient to effectively replenish the natural population. Although the breeding and release techniques for Chinese sturgeon have become increasingly sophisticated, the rearing of juvenile Chinese sturgeon still relies on live feed such as tubifex worms. This method is not only costly but also prone to polluting the aquatic environment and spreading pathogens, hindering the large-scale development of Chinese sturgeon fry farming. In recent years, with the maturation of first-generation breeding broodstock, the scale of second-generation fry farming has gradually expanded. However, due to a lack of understanding of the essential nutrient requirements and physiological metabolic characteristics of Chinese sturgeon during its early development, there has been a persistent shortage of formulated feeds for Chinese sturgeon juveniles both domestically and internationally. This severely restricts the large-scale development of Chinese sturgeon fry farming and limits the scale of restocking and release programs. Summary of the Invention

[0003] This invention provides a formulated feed for Chinese sturgeon larvae and juveniles. This formulated feed can promote the growth of Chinese sturgeon larvae and juveniles, while using less fishmeal, which can reduce the feed conversion ratio and thus reduce production and breeding costs.

[0004] The present invention also provides a method for preparing the above-mentioned compound feed, which is simple and quick to operate, and the process is scientific and reasonable. The compound feed prepared can not only promote the growth of Chinese sturgeon larvae and juveniles, but also reduce production and breeding costs.

[0005] This invention provides a formulated feed for juvenile and young Chinese sturgeon, comprising, by weight percentage: 20%-40% fish meal, 0%-20% cottonseed protein concentrate, 10%-30% soybean protein concentrate, 12%-18% wheat flour, 2%-6% blood cell meal, 0.5%-2% calcium dihydrogen phosphate, 0.2%-0.8% choline chloride, 1%-2% phospholipid oil, 2%-5% fish oil, 2%-4% soybean oil, 0.5%-1% compound vitamins, 0.5%-1% compound minerals, 0%-6% glutamic acid, and 0%-10% microcrystalline cellulose.

[0006] The compound feed described above contains fishmeal at a mass percentage of 25%-35%, cottonseed protein concentrate at a mass percentage of 5%-15%, and soybean protein concentrate at a mass percentage of 18%-25%.

[0007] In the compound feed described above, the mass ratio of fishmeal, cottonseed protein concentrate, and soybean protein concentrate is (2.5-3.5):(0.5-1.5):(1.5-2.5).

[0008] In the compound feed described above, the mass percentage of blood cell meal is 2%-6%, and the mass percentage of glutamic acid is 1.5%-2.5%.

[0009] In the compound feed described above, the mass ratio of blood cell meal to glutamic acid is (1.5-2.5):1.

[0010] The compound feed described above contains, per kilogram, 15-25 mg of vitamin A, 5-15 mg of vitamin D3, 300-500 mg of vitamin E, 15-25 mg of vitamin K3, 50-150 mg of niacin, 45-55 mg of riboflavin, 25-35 mg of pyridoxine, 20-25 mg of thiamine, 35-45 mg of D-calcium pantothenate, 1-3 mg of biotin, 5-15 mg of folic acid, 5-10 mg of vitamin B12, 900-1200 mg of ascorbic acid, 150-250 mg of inositol, with the remainder being corn gluten meal.

[0011] The compound feed described above contains, per kilogram, 3-5g MgSO4·7H2O, 5-8g Na2SO4, 4-8g K2SO4, 2-5g CaCl2·2H2O, 0.5-1g FeSO4, 0.5-1.5g calcium lactate, 0.1-0.3g ZnSO4·7H2O, 0.04-0.06g MnSO4·4H2O, 0.1-0.3g CuSO4·5H2O, 0.3-0.5g CoSO4, 0.01-0.03g KI, with the remainder being zeolite powder.

[0012] The present invention also provides a method for preparing the above-mentioned compound feed, comprising the following steps:

[0013] Step 1: Mix the first raw material to obtain the first mixture.

[0014] Step 2: Crush the first mixture, add the second raw material, mix, and then steam condition to obtain the second mixture;

[0015] Step 3: The second mixture is subjected to pelleting and drying processes in sequence to obtain compound feed;

[0016] The first raw material, by weight percentage, includes: fish meal 20%-40%, cottonseed protein concentrate 0%-20%, soybean protein concentrate 10%-30%, wheat flour 12%-18%, blood cell powder 2%-6%, calcium dihydrogen phosphate 0.5%-2%, choline chloride 0.2%-0.8%, compound vitamins 0.5%-1%, compound minerals 0.5%-1%, glutamic acid 0%-6%, and microcrystalline cellulose 0%-10%.

[0017] The second raw material includes, by weight percentage: 1%-2% phospholipid oil, 2%-5% fish oil, and 2%-4% soybean oil.

[0018] In the preparation method described above, in step 2, the particle size of the first mixture after crushing is 10 μm-25 μm; and / or,

[0019] In step 3, the particle size of the compound feed is 1mm-2mm.

[0020] In the preparation method described above, in step 2, the temperature of the steam conditioning is 100℃-120℃, and the time is 3-8 minutes.

[0021] This invention provides a formulated feed for Chinese sturgeon larvae and juveniles. This feed, through the combined action of multiple components including fishmeal, specific plant proteins, amino acids, fats, vitamins, minerals, and cellulose, provides the essential nutrients for the growth and development of Chinese sturgeon larvae and juveniles, thereby increasing their weight gain rate and specific growth rate, and promoting their overall growth and development. Furthermore, by adding low-cost plant-based soybean protein concentrate and cottonseed protein concentrate to this feed, the amount of expensive animal-based fishmeal used can be reduced, thus lowering the feed conversion ratio and reducing the production and breeding costs of Chinese sturgeon larvae and juveniles. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below. The specific embodiments listed below are merely descriptions of the principles and features of the present invention, and the examples are only for explaining the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] The first aspect of this invention provides a compound feed for juvenile Chinese sturgeon, comprising, by weight percentage: 20%-40% fish meal, 0%-20% cottonseed protein concentrate, 10%-30% soybean protein concentrate, 12%-18% wheat flour, 2%-6% blood cell meal, 0.5%-2% calcium dihydrogen phosphate, 0.2%-0.8% choline chloride, 1%-2% phospholipid oil, 2%-5% fish oil, 2%-4% soybean oil, 0.5%-1% compound vitamins, 0.5%-1% compound minerals, 0%-6% glutamic acid, and 0%-10% microcrystalline cellulose.

[0024] Compared to their adult and subadult stages, Chinese sturgeon exhibits lower feeding rates, slower growth, and lower feed conversion rates during their larval and juvenile stages, leading to higher mortality rates and making aquaculture more difficult. Therefore, this invention provides a formulated feed for Chinese sturgeon larvae and juveniles that effectively improves the weight gain rate and specific growth rate of larvae and juveniles while reducing the feed conversion ratio. Larvae and juveniles refer to the two early developmental stages in a fish's life cycle, from hatching from the egg membrane to the full development of scales. Fishmeal refers to a high-protein feed ingredient made from one or more fish species, processed through degreasing, dehydration, and grinding. Its crude protein content can reach over 55%, and it has a complete and balanced amino acid profile, significantly contributing to the growth and development of Chinese sturgeon larvae and juveniles and improving their survival rate. This invention does not limit the specific species of fish used in the fishmeal; those skilled in the art can select them as needed.

[0025] Cottonseed protein concentrate is a novel plant protein source obtained by low-temperature extraction, phenol removal, and moderate sugar removal of cottonseed. It has a high protein content, amino acids that are similar to fishmeal, good palatability, and no allergenic antigens.

[0026] Soy protein concentrate is a soy protein product made from soybeans through a series of processing techniques to remove oils and low-molecular-weight soluble non-protein components. It is rich in amino acids, has a high digestibility and absorption rate in juvenile Chinese sturgeon, and is palatable.

[0027] Flour is a powdery substance made from wheat that can provide energy for juvenile and young Chinese sturgeon. It has good palatability and can also act as a binder in formulated feed. Based on the protein content, flour can be classified into high-gluten flour, medium-gluten flour, low-gluten flour, and gluten-free flour. This invention does not limit the specific type of flour; those skilled in the art can select according to their needs.

[0028] Blood cell powder refers to the powder obtained by separating blood cells from animal blood under low-temperature conditions through a series of separation processes, followed by spray drying. It has a high crude protein content and is rich in lysine, leucine, valine, histidine, phenylalanine, and tryptophan, but its palatability is poor. This invention does not limit the specific source of animal blood in the blood cell powder; those skilled in the art can choose according to their needs.

[0029] Calcium dihydrogen phosphate can be used as a feed additive to supplement the calcium and phosphorus nutrition of juvenile and young Chinese sturgeon, and it has high water solubility and high absorption rate.

[0030] Choline chloride can be used as a multifunctional feed additive to promote the growth and development of Chinese sturgeon larvae and juveniles, improve their lipid metabolism and immune function, and increase feed conversion rate.

[0031] Phospholipid oil is a byproduct of soybean oil degumming, obtained through vacuum drying and decolorization; fish oil is a byproduct of fishmeal processing, obtained by steaming, pressing and refining fish and its waste; soybean oil is an oil extracted from soybeans; phospholipid oil, fish oil and soybean oil can be used as fat sources in compound feed.

[0032] Complex vitamins refer to two or more vitamins; complex minerals refer to two or more minerals. Adding complex vitamins and complex minerals to formulated feed can meet the basic nutritional needs of juvenile and young Chinese sturgeon. In this invention, the complex vitamins and complex minerals in the formulated feed can exist in the form of premixes, that is, complex vitamins can be a homogeneous mixture of one or more vitamins with a carrier or diluent in a certain proportion; complex minerals can be a homogeneous mixture of one or more minerals with a carrier or diluent in a certain proportion.

[0033] Glutamic acid, chemically known as α-aminoglutaric acid, is an organic compound with the chemical formula C5H9NO4. It is an acidic amino acid that has a good feeding attraction effect on juvenile and young Chinese sturgeon, not only increasing their feeding rate but also promoting muscle protein synthesis and body growth.

[0034] The main component of microcrystalline cellulose is a linear polysaccharide linked by β-1,4-glucosidic bonds. It can be used as a fiber source in compound feed and is often used as a filler in aquatic feed to balance feed formulations.

[0035] Therefore, the formulated feed for Chinese sturgeon larvae and juveniles provided by this invention uses fishmeal, soybean protein concentrate, and cottonseed protein concentrate as the main protein sources, phospholipid oil, fish oil, and soybean oil as the fat sources, wheat flour as the sugar source, and microcrystalline cellulose as the fiber source. It also adds compound vitamins and minerals to meet the basic nutritional needs of Chinese sturgeon larvae and juveniles, adds calcium dihydrogen phosphate to provide phosphorus and calcium sources, and adds blood cell meal, choline chloride, and glutamic acid to further promote the growth of Chinese sturgeon larvae and juveniles. The formulated feed of this invention includes the above-mentioned specific components, and by limiting the mass percentage of each component within a specific range, the synergistic effect between the components is enhanced, meeting the nutritional needs of Chinese sturgeon larvae and juveniles from multiple dimensions, increasing their weight gain rate and specific growth rate, and enabling them to grow and develop better. In addition, the protein sources in the compound feed, through the reasonable ratio of animal protein fishmeal and plant protein soybean protein concentrate and cottonseed protein concentrate, not only provide the necessary nutrients for Chinese sturgeon fry and juveniles, but also reduce the content of expensive animal protein fishmeal by adding low-cost plant protein, thereby reducing the feed conversion ratio and thus reducing production and breeding costs.

[0036] It is understandable that the mass percentage of a certain component in a compound feed refers to the proportion of the mass of that component to the total mass of the compound feed. For example, fishmeal 20%-40% means that the mass of fishmeal accounts for 20%-40% of the total mass of the compound feed.

[0037] In one specific embodiment, the compound feed contains 25%-35% fishmeal, 5%-15% cottonseed protein concentrate, and 18%-25% soybean protein concentrate.

[0038] Although fishmeal is an excellent feed ingredient, its high price leads to high production costs for raising juvenile Chinese sturgeon. Through long-term research, the inventors discovered that combining fishmeal, cottonseed protein concentrate, and soybean protein concentrate within the specified mass content range can meet the nutritional requirements of juvenile Chinese sturgeon while further reducing the cost of compound feed preparation.

[0039] Specifically, equal masses of cottonseed protein concentrate and soy protein concentrate can be used to replace equal masses of fishmeal. For example, 10% cottonseed protein concentrate and 20% soy protein concentrate can be used to replace 30% fishmeal.

[0040] In the present invention, the mass ratio of fish meal, cottonseed protein concentrate, and soybean protein concentrate in the compound feed is (2.5-3.5):(0.5-1.5):(1.5-2.5).

[0041] When the mass ratio of fishmeal, cottonseed protein concentrate, and soybean protein concentrate in the compound feed meets the requirements of (2.5-3.5):(0.5-1.5):(1.5-2.5), it can further increase the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles, and reduce the feed conversion ratio.

[0042] In one specific embodiment, the compound feed contains 2%-6% by mass of blood cell meal and 1.5%-2.5% by mass of glutamic acid.

[0043] Because blood cell powder is rich in nutrients and high in crude protein, but has poor palatability, its use alone can lead to a decrease in the feeding rate of Chinese sturgeon larvae and juveniles. Therefore, the inventors have found that when blood cell powder and glutamic acid are combined within the above-mentioned mass content range, glutamic acid has a good appetite-inducing effect on Chinese sturgeon larvae and juveniles, and can also supplement the glutamic acid content lacking in blood cell powder, thereby improving the feeding rate of Chinese sturgeon larvae and juveniles, promoting their growth, and reducing the feed conversion ratio.

[0044] In the present invention, the mass ratio of blood cell powder to glutamic acid in the compound feed is (1.5-2.5):1.

[0045] When the mass ratio of blood cell meal to glutamic acid in the compound feed meets the requirement of (1.5-2.5):1, it can further improve the feeding rate of Chinese sturgeon larvae and juveniles, increase the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles, and reduce the feed conversion ratio.

[0046] In one specific embodiment, each kilogram of the multivitamin contains 15-25 mg of vitamin A, 5-15 mg of vitamin D3, 300-500 mg of vitamin E, 15-25 mg of vitamin K3, 50-150 mg of niacin, 45-55 mg of riboflavin, 25-35 mg of pyridoxine, 20-25 mg of thiamine, 35-45 mg of D-calcium pantothenate, 1-3 mg of biotin, 5-15 mg of folic acid, 5-10 mg of vitamin B12, 900-1200 mg of ascorbic acid, 150-250 mg of inositol, and the remainder is corn gluten powder.

[0047] Among them, biotin uses maltodextrin as a carrier, and its mass percentage is 2%, that is, the mass of biotin accounts for 2% of the total mass of biotin and maltodextrin.

[0048] Vitamin B12 uses corn starch as a carrier, and its mass percentage is 1%, meaning that the mass of vitamin B12 accounts for 1% of the total mass of vitamin B12 and corn starch.

[0049] The above-mentioned compound vitamins contain all the vitamins necessary for growth and development. Combining them in the above-mentioned proportions can meet the vitamin requirements of Chinese sturgeon larvae and juveniles, thus making the compound feed more nutritionally complete and further enhancing its nutritional role.

[0050] Each kilogram of the complex minerals contains 3-5g MgSO4·7H2O, 5-8g Na2SO4, 4-8g K2SO4, 2-5g CaCl2·2H2O, 0.5-1g FeSO4, 0.5-1.5g calcium lactate, 0.1-0.3g ZnSO4·7H2O, 0.04-0.06g MnSO4·4H2O, 0.1-0.3g CuSO4·5H2O, 0.3-0.5g CoSO4, 0.01-0.03g KI, with the balance being zeolite powder.

[0051] The above-mentioned compound minerals contain various minerals necessary for growth and development. Combining them according to the above content can meet the mineral requirements of Chinese sturgeon fry and juveniles, thus making the formulated feed more comprehensive in nutrition and further enhancing its nutritional role.

[0052] A second aspect of the present invention provides a method for preparing the compound feed provided in the first aspect of the present invention, comprising the following steps:

[0053] Step 1: Mix the first raw material to obtain the first mixture.

[0054] Step 2: Crush the first mixture, add the second raw material, mix, and then steam condition to obtain the second mixture;

[0055] Step 3: The second mixture is subjected to pelleting and drying processes in sequence to obtain compound feed;

[0056] The first raw material, by weight percentage, includes: fish meal 20%-40%, cottonseed protein concentrate 0%-20%, soybean protein concentrate 10%-30%, wheat flour 12%-18%, blood cell powder 2%-6%, calcium dihydrogen phosphate 0.5%-2%, choline chloride 0.2%-0.8%, compound vitamins 0.5%-1%, compound minerals 0.5%-1%, glutamic acid 0%-6%, and microcrystalline cellulose 0%-10%.

[0057] The second raw material, by weight percentage, includes: 1%-2% phospholipid oil, 2%-5% fish oil, and 2%-4% soybean oil.

[0058] This invention first mixes and crushes the first raw material before adding the second raw material. This is because the first raw material mainly consists of solid components, while the second raw material mainly consists of liquid components. Separating the first and second raw materials and mixing and crushing the first raw material first ensures more thorough mixing and smaller particle size, facilitating subsequent operations. After adding the second raw material, mixing continues and steam conditioning is performed to obtain a second mixture. Finally, the second mixture undergoes granulation and drying processes to obtain a formulated feed. The preparation method provided by this invention is simple, quick, and scientifically sound. The formulated feed not only promotes the growth of juvenile and young Chinese sturgeon but also reduces production and aquaculture costs.

[0059] The mixing process for the first raw material is primarily aimed at ensuring it is thoroughly mixed to facilitate subsequent processing. Therefore, this invention does not limit the specific method of mixing, as long as the first raw material is sufficiently mixed.

[0060] In order to promote uniform mixing of the first raw material, in one embodiment of the present invention, the components with a mass percentage of more than 10% in the first raw material are first crushed to make them easier to mix with other components, and then stirred evenly by a mixer. The mixing sequence follows the principle of gradually expanding the mixing of small materials, which can further improve the mixing effect.

[0061] Next, in order to prepare compound feed that meets the particle size requirements, the first mixture needs to be crushed to facilitate subsequent operations. This invention does not limit the specific method of crushing, as long as the first raw material can be crushed. In one embodiment of this invention, the crushing process is ultrafine grinding. Ultrafine grinding is achieved using an ultrafine grinder, which can utilize air separation, heavy-pressure grinding, and shearing to achieve ultrafine grinding of dry materials.

[0062] After crushing the first mixture, a second raw material is added and mixed, followed by steam conditioning to obtain the second mixture. Steam conditioning refers to the pretreatment of feed raw materials with steam before pelleting to improve the stability and quality of pelleted feed.

[0063] Finally, the second mixture is first granulated and then dried to obtain compound feed. Granulation is the process of processing the second mixture into granules of a specific shape and size. Granulation can break down and gelatinize starch, kill pathogenic microorganisms, reduce the possibility of mold growth, improve feed digestibility and absorption, improve palatability, and ensure the uniformity of feed components, preventing animals from being picky eaters. Granulated feed pellets are easy to feed, occupy little space, and are easy to store and transport. This invention does not limit the specific method of granulation, as long as it can granulate the second mixture. In one embodiment of this invention, the granulation process is achieved using an extrusion pellet mill.

[0064] Furthermore, the pelleting temperature can be 100℃, which helps the feed pellets to form better.

[0065] Drying is the process of removing moisture from feed pellets, ensuring the moisture content by mass does not exceed 8%, effectively preventing mold growth and facilitating storage and transportation. To further improve the nutritional value of the feed and prevent fatty acid oxidation caused by high temperatures, this invention employs low-temperature drying. Specifically, the drying temperature can be 75°C.

[0066] In one specific embodiment, in step 2, the particle size of the first mixture after crushing is 10μm-25μm; and / or,

[0067] In step 3, the particle size of the compound feed is 1mm-2mm.

[0068] The present invention limits the particle size of the first mixture after crushing to facilitate subsequent operations.

[0069] In this invention, the particle size of the formulated feed is 1mm-2mm, which is consistent with the mouth size of Chinese sturgeon larvae and juveniles, and is beneficial for their feeding.

[0070] In the present invention, in step 2, the temperature of steam conditioning is 100℃-120℃, and the time is 3-8 minutes.

[0071] Steam conditioning alters the properties of powdered feed before pelleting by injecting an appropriate amount of dry saturated steam. It can add the necessary moisture for pelleting, providing lubrication and reducing friction. Controlling the steam conditioning temperature promotes starch gelatinization and protein denaturation, improving the nutrient digestibility of compound feeds, while also effectively killing harmful bacteria. Controlling the steam conditioning time regulates the degree of contact and mixing between the steam and the powdered feed, further promoting starch gelatinization to some extent.

[0072] The present invention limits the temperature of steam conditioning to 100℃-120℃ and the time to 3-8 minutes, which helps to further enhance the effect of steam conditioning.

[0073] The technical solution of this application will be further explained and illustrated below with reference to specific embodiments.

[0074] To facilitate understanding, the relevant technical terms involved in the embodiments of this application will first be explained and described.

[0075] In this invention, the first raw material includes fish meal, cottonseed protein concentrate, soybean protein concentrate, flour, blood cell powder, calcium dihydrogen phosphate, choline chloride, compound vitamins, compound minerals, glutamic acid and microcrystalline cellulose; the second raw material includes fish oil, soybean oil and phospholipid oil.

[0076] In this invention, the principle of gradually increasing the amount of raw materials refers to adding the first raw material step by step according to the principle of increasing the mass percentage content.

[0077] In this invention, the feeding rate refers to the daily feeding rate of fish, which is obtained by the following formula: W a / W b *100%; of which, W a This refers to the quality of feed given daily, W b This refers to the fish's weight.

[0078] In this invention, the weight gain rate of Chinese sturgeon larvae and juveniles is obtained by the following formula: (W2-W1) / W1*100%; where W1 refers to the weight of Chinese sturgeon larvae and juveniles before the start of breeding, and W2 refers to the weight of Chinese sturgeon larvae and juveniles after 8 weeks of breeding.

[0079] In this invention, the specific growth rate refers to the ratio of the growth rate to the number of growth days, calculated using the following formula: (lnW2-lnW1)*(lnW2-lnW1)*100% / t, where W1 refers to the weight of the Chinese sturgeon larvae before the start of rearing, W2 refers to the weight of the Chinese sturgeon larvae after 8 weeks of rearing, and t refers to the number of rearing days. The specific growth rate is a commonly used indicator for measuring growth status; a higher specific growth rate indicates a faster daily weight gain.

[0080] In this invention, the feed conversion ratio is obtained by the following formula: W c / W d *100%, of which, W c W refers to the mass of formulated feed consumed by juvenile and young Chinese sturgeon during the 8-week rearing period. d This refers to the difference between the weight of Chinese sturgeon larvae / juveniles after 8 weeks of rearing and their weight before the start of rearing. A lower feed conversion ratio indicates a higher conversion rate and better performance of the formulated feed.

[0081] In the following examples, cottonseed protein concentrate was purchased from Xinjiang Chengrun Jinlan Biotechnology Co., Ltd.; fish meal, fish oil, soybean oil, phospholipid oil, blood cell powder, and soybean protein concentrate were all purchased from Tianmen Haida Feed Co., Ltd. Other reagents without specified manufacturers were commercially available or readily available through public channels. Experimental methods without specific conditions were generally performed under standard conditions or as recommended by the manufacturer.

[0082] Example 1:

[0083] (1) Preparation of compound feed

[0084] Using fishmeal, soybean protein concentrate, and cottonseed protein concentrate as the main protein sources, and phospholipid oil, fish oil, and soybean oil as the fat sources, compound feeds were prepared by replacing 10%, 20%, 30%, or 40% of the fishmeal in the feed with 10%, 20%, 30%, or 40% of the fishmeal by ...

[0085] According to Table 1, accurately weigh the first raw material, crush the components with a mass percentage of more than 10% in the first crushing, and then mix and stir evenly in a mixer. The mixing order follows the principle of gradually increasing the size of the small materials to obtain the mixture.

[0086] The mixture is ultra-finely pulverized to a particle size of 10μm-25μm, the second raw material is added, and then it is conditioned with steam for 4 minutes. During the conditioning process, the temperature of the mixture and the surrounding space is maintained at 110℃ to obtain the conditioned mixture.

[0087] The conditioned mixture is added to an extrusion pellet mill and pelleted at 100°C. Then it is dried at 75°C for 30 minutes to ensure that the moisture content does not exceed 8% by mass. After cooling to room temperature, it is sieved to remove powder, resulting in a water-sinking extruded compound feed with a particle size of 1mm-2mm.

[0088] Table 1

[0089]

[0090]

[0091] (2) Farming of Chinese sturgeon larvae and juveniles

[0092] Eighty-one hundred healthy, uniformly growing Chinese sturgeon juveniles with an average weight of 4 ± 0.25 g were selected and placed in 27 round plastic containers (approximately 400 L each) at a rate of 30 juveniles per container. Nine treatment groups were established, with three biological replicates per group. Each group was fed formulated feeds according to groups 1-9 above, and the experiment was conducted for eight weeks. The rearing conditions were as follows: feeding was conducted twice daily, at 09:00 and 16:00, with a feeding rate of 3%; water was changed once daily, replacing one-third of the total water volume, and juvenile mortality was recorded. During the experiment, the water temperature was maintained between 19.0℃ and 20.5℃, dissolved oxygen was maintained at no less than 8 mg / L, ammonia nitrogen concentration was less than 0.1 mg / L, and pH was between 7.0 and 7.5; the light exposure time was from 08:00 to 20:00 daily. After the breeding experiment, the weight gain rate, specific growth rate and feed conversion ratio of Chinese sturgeon were statistically analyzed. The results are shown in Table 2. The data in Table 2 are expressed as mean ± standard error. Data with the same superscript letter in the same column indicate no significant difference between groups (P>0.05), while data with different lowercase superscript letters indicate significant differences between groups (P<0.05).

[0093] Table 2

[0094]

[0095]

[0096] As shown in Table 2, groups 2, 4, 6, and 8 involved replacing 10%, 20%, 30%, or 40% of fishmeal with 10%, 20%, 30%, or 40% cottonseed protein concentrate, respectively. Compared to group 1, groups 2, 4, and 6 showed no significant differences in weight gain rate, specific growth rate, and feed conversion ratio of Chinese sturgeon larvae and juveniles. However, group 8 showed a significant decrease in weight gain rate and specific growth rate, and a significant increase in feed conversion ratio. These results indicate that the optimal proportion of cottonseed protein concentrate to replace fishmeal is 30%. Groups 3, 5, 7, and 9 involved replacing 10%, 20%, 30%, or 40% of fishmeal with 10%, 20%, 30%, or 40% soybean protein concentrate, respectively. Compared to group 1, groups 3, 5, and 7 showed no significant differences in weight gain rate, specific growth rate, and feed conversion ratio of Chinese sturgeon larvae and juveniles. However, group 9 showed a significant decrease in weight gain rate and specific growth rate, and a significant increase in feed conversion ratio. The above results indicate that the optimal ratio for replacing fishmeal with soy protein concentrate is 30%.

[0097] It is evident that, while maintaining the growth performance of Chinese sturgeon larvae and juveniles, cottonseed protein concentrate or soybean protein concentrate can effectively replace 30% of fishmeal, reducing the amount of fishmeal used, decreasing feed formulation costs, and lowering production and aquaculture costs.

[0098] Example 2:

[0099] Based on the results of Example 1, cottonseed protein concentrate or soy protein concentrate can effectively replace 30% of fishmeal. Further research will be conducted on the optimal mass ratio of fishmeal, cottonseed protein concentrate, and soy protein concentrate.

[0100] (1) Preparation of compound feed

[0101] The mass ratios of fishmeal, cottonseed protein concentrate, and soybean protein concentrate were 1:1:0, 3:2:1, 2:1:1, 3:1:2, or 1:0:1. The compound feeds for groups 6, 7, 10, 11, and 12 were prepared according to the compound feed preparation method in Example 1, as detailed in Table 3.

[0102] Table 3

[0103] Group 6 10 11 12 7 Fish meal (%) 30 30 30 30 30 flour(%) 14 14 14 14 14 Cottonseed protein concentrate (%) 30 20 15 10 - Soy protein concentrate (%) - 10 15 20 30 Blood cell powder (%) 3.5 3.5 3.5 3.5 3.5 Calcium dihydrogen phosphate (%) 1.5 1.5 1.5 1.5 1.5 Choline chloride 50% (%) 0.5 0.5 0.5 0.5 0.5 Phospholipid oil (%) 1.5 1.5 1.5 1.5 1.5 fish oil(%) 3.5 3.5 3.5 3.5 3.5 Soybean oil (%) 3 3 3 3 3 Multivitamins (%) 0.75 0.75 0.75 0.75 0.75 Complex minerals (%) 0.75 0.75 0.75 0.75 0.75 Microcrystalline fibers (%) 11 11 11 11 11 total 100 100 100 100 100

[0104] (2) Farming of Chinese sturgeon larvae and juveniles

[0105] Forty-fivety healthy, uniformly growing Chinese sturgeon larvae were selected, with an average weight of 4 ± 0.25 g. Thirty larvae were placed in 15 round plastic containers, each with a volume of approximately 400 L. Five treatment groups were set up, with three biological replicates in each group. The larvae were fed formulated feeds according to groups 6, 7, 10, 11, and 12, respectively, for eight weeks. All other rearing conditions were the same as in Example 1. After the rearing experiment, the weight gain rate, specific growth rate, and feed conversion ratio of the Chinese sturgeon larvae were statistically analyzed. The results are shown in Table 4. Data in Table 4 are expressed as mean ± standard error. Data with no superscript or the same superscript letter indicate no significant difference between groups (P > 0.05), while data with different lowercase superscript letters indicate significant differences between groups (P < 0.05).

[0106] Table 4

[0107]

[0108]

[0109] As shown in Table 4, the mass ratios of different amounts of fishmeal, cottonseed protein concentrate, and soybean protein concentrate in the formulated feed significantly affected the growth performance of Chinese sturgeon larvae and juveniles. With increasing proportions of soybean protein concentrate in the formulated feed, the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles showed a trend of first increasing and then decreasing. Furthermore, in group 12 (mass ratio of fishmeal, cottonseed protein concentrate, and soybean protein concentrate of 3:1:2), the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles reached their highest values, while the feed conversion ratio (FCR) reached its lowest value. These results indicate that a FCR of 30% fishmeal, 10% cottonseed protein concentrate, and 20% soybean protein concentrate, i.e., a FCR of 3:1:2, is most beneficial for the growth of Chinese sturgeon larvae and juveniles, and also results in the lowest FCR, effectively reducing production and aquaculture costs.

[0110] Example 3:

[0111] Based on the results of Examples 1 and 2, the effect of the mass ratio of blood cell powder to glutamic acid on the growth performance of Chinese sturgeon larvae and juveniles was further investigated.

[0112] (1) Preparation of compound feed

[0113] Compound feeds for groups 13-27 were prepared by adding different levels of blood cell powder (0%, 4%, or 8%) and glutamic acid (0.5%, 1%, 2%, 3%, or 5%), following the preparation method for compound feeds in Example 1, as detailed in Table 5. In the compound feeds for groups 13-27, only the ratio of blood cell powder to glutamic acid was changed; the remainder was balanced with microcrystalline cellulose. The other components and proportions remained consistent with those of group 12.

[0114] Table 5

[0115]

[0116]

[0117] (2) Farming of Chinese sturgeon larvae and juveniles

[0118] One hundred and thirty-five healthy Chinese sturgeon juveniles with uniform growth and an average weight of 4 ± 0.25 g were selected and placed in 45 round plastic buckets (approximately 400 L each) at a ratio of 30 juveniles per bucket. Fifteen treatment groups were set up, with three biological replicates in each group. The groups were fed formulated feeds according to the formulas for groups 13-27 above, and the rearing experiment lasted for eight weeks, with other rearing conditions the same as in Example 1. After the rearing experiment, the weight gain rate, specific growth rate, and feed conversion ratio of the Chinese sturgeon juveniles were statistically analyzed. The results are shown in Table 6. The data in Table 6 are expressed as mean ± standard error. Data in the same column without a letter or with the same letter indicate no significant difference between groups (P > 0.05), while data with different lowercase letters indicate significant differences between groups (P < 0.05).

[0119] Table 6

[0120]

[0121]

[0122] As shown in Table 6, with the increase of the proportion of hemoglobin in the formulated feed, the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles showed an initial increase followed by a decrease, reaching the highest value in the 4% hemoglobin group. Similarly, with the increase of the proportion of glutamic acid in the formulated feed, the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles also showed an initial increase followed by a decrease, reaching the highest value in the 2% glutamic acid group. It can be found that the simultaneous addition of 4% hemoglobin and 2% glutamic acid (group 20) significantly improved the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles, and also resulted in the lowest feed conversion ratio. These results indicate that the simultaneous addition of 4% hemoglobin and 2% glutamic acid (i.e., a hemoglobin to glutamic acid mass ratio of 2:1) to the formulated feed is beneficial to the growth of Chinese sturgeon larvae and juveniles, and results in the lowest feed conversion ratio, thus reducing production and aquaculture costs.

[0123] In summary, this invention provides a formulated feed for Chinese sturgeon larvae and juveniles and its preparation method. By limiting the types and mass percentages of each component within a specific range, the formulated feed of this invention enhances the synergistic effect between the components, meeting the nutritional needs of Chinese sturgeon larvae and juveniles from multiple dimensions, increasing their weight gain rate and specific growth rate, and promoting better growth and development. Furthermore, while providing essential nutrients, the formulated feed of this invention reduces the content of expensive animal protein fishmeal by adding low-cost plant protein, thereby lowering the feed conversion ratio and reducing production and breeding costs. Simultaneously, the combination of blood cell meal and glutamic acid in this formulated feed improves the feed intake rate of Chinese sturgeon larvae and juveniles, promotes their growth, and further reduces the feed conversion ratio. In the compound feed of the present invention, when the mass percentages of fish meal, cottonseed protein concentrate, soybean protein concentrate, blood cell meal and glutamic acid are 30%, 10%, 20%, 4% and 2% respectively, it can not only increase the weight gain rate and specific growth rate of Chinese sturgeon larvae and juveniles, thereby promoting the growth of Chinese sturgeon larvae and juveniles, but also reduce the amount of fish meal used, reduce the feed conversion ratio, and thus reduce production and breeding costs.

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A formulated feed for juvenile and young Chinese sturgeon, characterized in that, The ingredients, by weight percentage, include: fish meal 20%-40%, cottonseed protein concentrate 0%-20%, soybean protein concentrate 10%-30%, flour 12%-18%, blood cell powder 2%-6%, calcium dihydrogen phosphate 0.5%-2%, choline chloride 0.2%-0.8%, phospholipid oil 1%-2%, fish oil 2%-5%, soybean oil 2%-4%, compound vitamins 0.5%-1%, compound minerals 0.5%-1%, glutamic acid 1.5%-2.5%, and microcrystalline cellulose 0%-10%; the mass ratio of blood cell powder to glutamic acid is (1.5-2.5):

1.

2. The compound feed according to claim 1, characterized in that, The fishmeal has a mass percentage content of 25%-35%, the cottonseed protein concentrate has a mass percentage content of 5%-15%, and the soybean protein concentrate has a mass percentage content of 18%-25%.

3. The compound feed according to claim 2, characterized in that, The mass ratio of the fish meal, the cottonseed protein concentrate, and the soybean protein concentrate is (2.5-3.5):(0.5-1.5):(1.5-2.5).

4. The compound feed according to any one of claims 1-3, characterized in that, Each kilogram of the aforementioned multivitamin contains 15-25 mg of vitamin A, 5-15 mg of vitamin D3, 300-500 mg of vitamin E, 15-25 mg of vitamin K3, 50-150 mg of niacin, 45-55 mg of riboflavin, 25-35 mg of pyridoxine, 20-25 mg of thiamine, 35-45 mg of D-calcium pantothenate, 1-3 mg of biotin, 5-15 mg of folic acid, 5-10 mg of vitamin B12, 900-1200 mg of ascorbic acid, 150-250 mg of inositol, with the remainder being corn gluten meal.

5. The compound feed according to any one of claims 1-4, characterized in that, The compound mineral contains 3-5 g per kilogram. 5-8 g 4-8 g 2-5 g 0.5-1 g 0.5-1.5 g calcium lactate, 0.1-0.3 g 0.04-0.06 g 0.1-0.3 g 0.3-0.5 g 0.01-0.03 g The remainder is zeolite powder.

6. The method for preparing compound feed according to any one of claims 1-5, characterized in that, Includes the following steps: Step 1: Mix the first raw material to obtain the first mixture. Step 2: Crush the first mixture, add the second raw material, mix, and then steam condition to obtain the second mixture; Step 3: The second mixture is subjected to pelleting and drying processes in sequence to obtain the compound feed; The first raw material comprises, by weight percentage: fish meal 20%-40%, cottonseed protein concentrate 0%-20%, soybean protein concentrate 10%-30%, flour 12%-18%, blood cell powder 2%-6%, calcium dihydrogen phosphate 0.5%-2%, choline chloride 0.2%-0.8%, compound vitamins 0.5%-1%, compound minerals 0.5%-1%, glutamic acid 1.5%-2.5%, and microcrystalline cellulose 0%-10%; the mass ratio of blood cell powder to glutamic acid is (1.5-2.5):

1. The second raw material, by weight percentage, includes: 1%-2% phospholipid oil, 2%-5% fish oil, and 2%-4% soybean oil.

7. The preparation method according to claim 6, characterized in that, In step 2, the particle size of the first mixture after crushing is 10 μm-25 μm; and / or, In step 3, the particle size of the compound feed is 1 mm-2 mm.

8. The preparation method according to any one of claims 6-7, characterized in that, In step 2, the temperature of the steam conditioning is 100 ℃-120 ℃, and the time is 3-8 minutes.

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