Breeding method of sturgeons, sturgeon feed and preparation method of sturgeon feed

Abstract

The invention discloses a culture method of sturgeons, a sturgeon feed and a preparation method of the sturgeon feed, and belongs to the technical field of aquaculture. The sturgeon feed comprises basic nutrient substances of protein, fat, vitamins and mineral substances, and in the feed, arachidonic acid accounts for 0.1-2% of the weight of the feed. In addition, the invention further provides a preparation method of the sturgeon feed, and the preparation method comprises the following steps: S1, mixing the fish oil, the soybean oil, the choline, the arachidonic acid, the compound multi-vitamins, the compound multi-minerals, the first flour and the water, and granulating to obtain first particles; s2, mixing the first particles, fish meal, soybean meal, chicken meal, squid visceral meal, sodium carboxymethyl cellulose, monocalcium phosphate and second flour, granulating and drying to obtain second particles. In addition, the invention further provides a culture method of the sturgeons. According to the feed provided by the invention, ovaries of the III-stage 10-age Yangtze River sturgeons can be developed to the IV stage.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, and in particular to a sturgeon breeding method, a sturgeon feed and a preparation method thereof. Background Art

[0002] Sturgeons are one of the earliest vertebrate groups. Fossils of Acipenseriformes fish were found as early as 200 million years ago in the Jurassic period of the Mesozoic Era. Acipenseriformes fish are characterized by large body, long lifespan and late sexual maturity. There are 27 species of sturgeons in the world. Most of them are endangered to varying degrees due to factors such as water conservancy project construction, fishing, shipping and pollution. There are 8 species of sturgeon in my country, including the Daurian sturgeon (Husodauricus) and Acipenser schrenckr in Heilongjiang; the Siberian sturgeon (Acipenser baer), small-bodied sturgeon (Acipenser ruthanus) and naked sturgeon (Acipenser nudiventris) in the Irtysh River and other waters in Xinjiang; as well as the river-sea migratory Chinese sturgeon (Acipenser sinensis Gray), the freshwater sedentary Yangtze sturgeon (Acipenser dabryanus), and the white sturgeon (Pesphurus gladius) that lives in the estuaries of the Yangtze River and other large rivers. Unfortunately, the white sturgeon, known as the "King of China's Freshwater Sturgeon", was declared functionally extinct in 2020. On July 21, 2022, the World Conservation Union (IUCN) announced that the Yangtze sturgeon was "extinct in the wild." The Chinese sturgeon is also facing the dilemma of continuous interruption of natural reproduction (2017-2023). If we do not take active and effective artificial protection measures, I am afraid that more and more sturgeon populations will disappear from our sight in the future.

[0003] The Yangtze sturgeon is a freshwater resident sturgeon in the middle and upper reaches of the Yangtze River in my country. It has a long sexual maturity cycle, with females reaching their first sexual maturity at 6 to 8 years old and males at 3 to 5 years old. After the 1980s, the size of the natural population shrank sharply, and its natural reproduction activities stopped after 2000. It was listed as a national first-class protected wild animal in 1988, listed as a protected species in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in 1997, and upgraded to a critically endangered (CR) species by the World Conservation Union (IUCN) in 2010. It was declared "extinct in the wild" by the World Conservation Union (IUCN) in 2022. A group of Yangtze sturgeon populations have been conserved under artificial conservation conditions, and breakthroughs have been made in the artificial breeding technology of its second generation, but large-scale breeding of this species has not yet been achieved. In the breeding process, it still faces problems such as slow growth and development, long initial sexual maturity, asynchronous development of males and females, and low ratio of sexually mature female fish. Recently, artificial breeding of the second generation of Yangtze sturgeon was carried out, and it was found that the success rate of induced spawning of female parents was only 33.33%. The absolute egg carrying capacity of farmed individuals was significantly lower than that of wild individuals, and the egg diameter was also smaller than that of wild individuals. There were three peaks of death during the seedling cultivation process. It can be seen that the regulation of gonadal development and improvement of reproductive performance of the second generation of Yangtze sturgeon parents are still key issues that need to be urgently addressed. Feeding is beneficial to promoting the development of Yangtze sturgeon, but there is currently a lack of feed that can successfully develop the ovaries of Yangtze sturgeon parents to stage IV. Summary of the invention

[0004] Recently, we conducted a comparative analysis of the nutritional components of different tissues of subadult Yangtze sturgeon and found that fat and long-chain highly unsaturated fat play an important role in gonadal development. Other studies on farmed fish have shown that dietary arachidonic acid has a positive effect on the synthesis of sex steroid hormones, gonadal development and reproductive performance of the parents. In view of the above review, the present invention mainly explores the effect of dietary arachidonic acid levels on the ovarian development of 10-year-old Yangtze sturgeon at stage III. It explores the preparation of different proportions of arachidonic acid feeds to culture Yangtze sturgeon broodstock for 12 months on the premise of meeting the basic nutritional needs of stage III broodstock of Yangtze sturgeon, and examines the effects of arachidonic acid on the growth, fatty acid deposition, inflammatory factors, developmental ratios and hormone synthesis of Yangtze sturgeon broodstock, thereby screening out an efficient Yangtze sturgeon broodstock feed formula and making it into a product for Yangtze sturgeon broodstock farming.

[0005] The purpose of the present invention is to overcome the above technical deficiencies, provide a sturgeon breeding method, a sturgeon feed and a preparation method thereof, and solve the technical problem in the prior art of how to use feed to successfully develop the ovaries of Yangtze sturgeon broodstock to stage IV.

[0006] To achieve the above technical purpose, the technical solution of the present invention provides a sturgeon feed, including basic nutrients such as protein, fat, vitamins and minerals, in which arachidonic acid accounts for 0.1% to 2% of the weight percentage of the feed.

[0007] In any embodiment, calculated by weight percentage, the composition includes: 30%-40% fish meal, 10%-20% soybean meal, 10%-15% chicken meal, 5%-7% squid viscera meal, 3%-4% fish oil, 3%-4% soybean oil, 20%-25% flour, 0.1%-0.4% choline, 1%-1.5% monocalcium phosphate, 1%-2% compound multivitamin, 2%-3% compound multimineral, 2%-3% sodium carboxymethyl cellulose and 0.1% to 2% arachidonic acid.

[0008] In any embodiment, probiotics 1%-1.5% are also included.

[0009] In any embodiment, the probiotic is Bacillus subtilis.

[0010] In any embodiment, gelatin 1%-3% is also included.

[0011] In addition, the present invention also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0012] S1. Mixing fish oil, soybean oil, choline, arachidonic acid, compound multivitamin, compound multimineral, first flour and water, and granulating to obtain first particles;

[0013] S2, mixing the first particles, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate and the second flour, granulating and drying to obtain the second particles.

[0014] In any embodiment, step S1 further includes mixing the probiotics and the third flour to obtain third particles, and mixing the third particles, fish oil, soybean oil, choline, arachidonic acid, compound multivitamins, compound multiminerals, the second flour and water to obtain the first particles.

[0015] In any embodiment, step S1 further includes spraying gelatin on the surface of the first particles to obtain the first particles having the surface coated with gelatin.

[0016] In any embodiment, in step S1, the mesh size of the first particles is 80-90 mesh.

[0017] In addition, the present invention also provides a method for breeding sturgeons, comprising the following steps:

[0018] Feed the above-mentioned sturgeon feed or the sturgeon feed prepared by the above-mentioned preparation method twice / day, adopt flow-through culture, the flow rate is 0.132-140m3 / min, the average water temperature during the culture period is 18.15-18.5℃, the water temperature range is 5.5℃~26.6℃, the average dissolved oxygen is 7.55-8mg / L, the dissolved oxygen range is 5.12mg / L~11.23mg / L, the pH is 7.91~8.15, and the ammonia nitrogen is 0.08~0.30mg / L;

[0019] When the water temperature drops below 10℃, natural lake water is used for low temperature and flow rate stimulation. The water temperature range is 5.5-12.4℃, and the average water temperature is 8.72-8.8℃.

[0020] Compared with the prior art, the beneficial effects of the present invention include: the sturgeon feed proposed in the present invention includes basic nutrients such as protein, fat, vitamins and minerals, and arachidonic acid accounts for 0.1% to 2% by weight of the feed. The present invention explores the effect of adding arachidonic acid to the feed on the ovarian development of 10-year-old Yangtze sturgeon in stage III, and explores the cultivation of Yangtze sturgeon broodstock for 12 months by adding arachidonic acid to the feed while meeting the basic nutritional needs of Yangtze sturgeon in stage III. It is concluded that the feed proposed in the present invention can develop the ovaries of 10-year-old Yangtze sturgeon in stage III to stage IV. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a B-ultrasound photo of sturgeon broodstock after one year of being fed with the feed proposed in Example 1 of the present invention;

[0022] Figure 2 This is a statistical result chart of blood sex hormones of sturgeon broodstock one year after being fed with the feeds proposed in Examples 1-2 of the present invention and Comparative Example 1. DETAILED DESCRIPTION

[0023] The "range" disclosed in the present application is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 60 to 120 and 80 to 110 is listed for a particular parameter, it is understood that a range of 60 to 110 and 80 to 120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following ranges can all be expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4 and 2 to 5. In the present application, unless otherwise specified, the numerical range "a to b" represents an abbreviation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0024] If there is no special explanation, the "include" and "comprising" mentioned in this application are open-ended or closed-ended. For example, the "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0025] If not specifically stated, in this application, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0026] This specific embodiment provides a sturgeon feed, comprising basic nutrients of protein, fat, vitamins and minerals, characterized in that arachidonic acid accounts for 0.1% to 2% of the weight percentage of the feed.

[0027] In some embodiments, the composition includes, by weight percentage, 30%-40% fish meal, 10%-20% soybean meal, 10%-15% chicken meal, 5%-7% squid viscera meal, 3%-4% fish oil, 3%-4% soybean oil, 20%-25% flour, 0.1%-0.4% choline, 1%-1.5% calcium dihydrogen phosphate, 1%-2% compound multivitamin, 2%-3% compound multimineral, 2%-3% sodium carboxymethyl cellulose and 0.1%-2% arachidonic acid. Under the coordination of various components, the basic nutritional requirements of Yangtze sturgeon III broodstock are met.

[0028] In some embodiments, probiotics 1%-1.5% are also included.

[0029] In some embodiments, the probiotics are Bacillus subtilis. After entering the intestinal tract of the sturgeon, Bacillus subtilis can promote the degradation of nutrients in the feed, so that the sturgeon can absorb and utilize the feed more fully.

[0030] In some embodiments, gelatin 1%-3% is also included.

[0031] In addition, the present invention also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0032] S1. Mixing fish oil, soybean oil, choline, arachidonic acid, compound multivitamin, compound multimineral, first flour and water, and granulating to obtain first particles;

[0033] S2, mixing the first particles, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate and the second flour, granulating and drying to obtain the second particles.

[0034] In some embodiments, step S1 further includes mixing probiotics and third flour to obtain third particles, and mixing the third particles, fish oil, soybean oil, choline, arachidonic acid, compound multivitamins, compound multiminerals, second flour and water to obtain the first particles. The probiotics are protected in the inner layer, which helps to prolong their effectiveness and can be released continuously, which helps the sturgeon digest and absorb the feed.

[0035] In some embodiments, step S1 further includes spraying gelatin on the surface of the first particle to obtain the first particle coated with gelatin. The first particle coated with gelatin helps the feed to enter the intestine and first digest the indigestible part outside the first particle. At the same time, the components in the first particle are slowly released, which can not only ensure the growth needs of the sturgeon, but also avoid the components in the first particle being discharged from the fish body without being fully absorbed, and further avoid the loss caused by the direct dispersion of arachidonic acid and other components of the feed into the water.

[0036] In some embodiments, the mesh size of the first particles is 80-90 mesh.

[0037] In addition, this specific embodiment also proposes a method for breeding sturgeons, comprising the following steps:

[0038] Feed the above-mentioned sturgeon feed or the sturgeon feed prepared by the above-mentioned preparation method twice / day, adopt flow-through culture, the flow rate is 0.132-140m3 / min, the average water temperature during the culture period is 18.15-18.5℃, the water temperature range is 5.5℃~26.6℃, the average dissolved oxygen is 7.55-8mg / L, the dissolved oxygen range is 5.12mg / L~11.23mg / L, the pH is 7.91~8.15, and the ammonia nitrogen is 0.08~0.30mg / L;

[0039] When the water temperature drops below 10℃, natural lake water is used for low temperature and flow rate stimulation. The water temperature range is 5.5-12.4℃, and the average water temperature is 8.72-8.8℃.

[0040] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0041] In the present invention, reference is made to “some embodiments”, “this embodiment”, examples, etc., which describe a subset of all possible embodiments, but it can be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0042] If similar descriptions of "first / second" appear in the application documents, the following instructions are added. In the following description, the terms "first\second\third" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged in a specific order or sequence where permitted, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0043] In this embodiment, the term "and / or" is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, object A and / or object B may represent three situations: object A exists alone, object A and object B exist at the same time, and object B exists alone.

[0044] Hereinafter, the embodiments of the present application will be described. The embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If no specific techniques or conditions are indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be obtained commercially.

[0045] It should be noted that in the following examples or comparative examples, each kilogram of feed contains vitamin premix: VB150 mg, VB2 200 mg, VB6 50 mg, VB 12 20mg, folic acid 15mg, V c 325mg, pantothenic acid 400mg, inositol 1500mg, D-biotin (2%) 5mg, niacin 750mg, V A 2.5mg, V E (50%) 250mg, VD3 2mg, V K 20mg.

[0046] Each kilogram of feed contains mineral salt premix: Ca(H2PO4)2 1800mg, KH2PO4 1350mg, NaCl 500mg, MgSO4 7H2O 750mg, NaH2PO4 2H2O 650mg, KI 1.5mg, COSO4 6H2O 2.5mg, CuSO4 5H2O 15mg, ZnSO47H2O 350mg, FeSO4 7H2O 1250mg, MnSO4 4H2O 80mg, Na2SeO36.00mg.

[0047] The gelatin solution in the following examples or comparative examples is a gelatin solution prepared by dissolving gelatin in deionized water. The mesh size of the first particles in the following examples is 80-90 meshes.

[0048] Example 1

[0049] The present embodiment provides a sturgeon feed, which includes, by weight percentage, 35% fish meal, 15% soybean meal, 10% chicken meal, 5% squid viscera powder, 3.5% fish oil, 3.5% soybean oil, 20.6% flour, 0.2% choline, 1.2% monocalcium phosphate, 1% compound multivitamin, 2% compound multimineral, 2% sodium carboxymethyl cellulose and 1% arachidonic acid.

[0050] This embodiment also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0051] Fish meal, soybean meal, chicken meal, squid viscera meal, flour, compound multivitamin, compound multi-mineral, choline, calcium dihydrogen phosphate and sodium carboxymethyl cellulose are mixed in a mixer, and then fish oil, soybean oil and arachidonic acid as well as water accounting for 15% of the total weight of each component are added to form a wet-based mixture, and the wet-based mixture is placed in a feed pellet machine and extruded to form cylindrical long strip particles, which are then blown dry in a cool and dry place and stored in a -20°C refrigerator for standby use.

[0052] Example 2

[0053] The present embodiment provides a sturgeon feed, which includes, by weight percentage, 35% fish meal, 15% soybean meal, 10% chicken meal, 5% squid viscera powder, 3% fish oil, 3% soybean oil, 20.6% flour, 0.2% choline, 1.2% monocalcium phosphate, 1% compound multivitamin, 2% compound multimineral, 2% sodium carboxymethyl cellulose and 2% arachidonic acid.

[0054] The preparation method of the sturgeon feed in this embodiment is the same as that in Example 1.

[0055] Example 3

[0056] The formula of the sturgeon feed proposed in this embodiment is the same as that in Example 1.

[0057] This embodiment also provides a method for preparing the sturgeon feed, comprising the following steps:

[0058] S1. According to the above ratio, fish oil, soybean oil, choline, arachidonic acid, compound multivitamin, compound multimineral, first flour and first water are mixed and granulated to obtain first granules; the amount of the first water is 8% of the mass of the first flour;

[0059] S2, mixing the first particles, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate, a second flour and a second water, granulating and drying to obtain a second particle; the amount of the second water is 10% of the mass of the second flour;

[0060] The mass ratio of the first flour to the second flour is 1:4, and the total amount of the first flour and the second flour is the amount of flour in the sturgeon feed formula.

[0061] Example 4

[0062] The formula of the sturgeon feed proposed in this embodiment is the same as that in Example 2.

[0063] This embodiment also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0064] S1. According to the above ratio, fish oil, soybean oil, choline, arachidonic acid, compound multivitamin, compound multimineral, first flour and first water are mixed and granulated to obtain first granules; the amount of the first water is 8% of the mass of the first flour;

[0065] S2, mixing the first particles, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate, a second flour and a second water, granulating and drying to obtain a second particle; the amount of the second water is 10% of the mass of the second flour;

[0066] The mass ratio of the first flour to the second flour is 1:4, and the total amount of the first flour and the second flour is the amount of flour in the sturgeon feed formula.

[0067] Example 5

[0068] The difference between the sturgeon feed of this embodiment and that of embodiment 3 is that the feed further comprises 1.5% of Bacillus subtilis.

[0069] This embodiment also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0070] S1. According to the above ratio, Bacillus subtilis, the third flour and the third water are mixed, and granulated to obtain the third granules; the third granules, fish oil, soybean oil, choline, arachidonic acid, compound multi-dimensional, compound multi-mineral, the first flour and the first water are mixed, and granulated to obtain the first granules; the amount of the third water is 5% of the mass of the third flour, and the amount of the first water is 8% of the mass of the first flour;

[0071] S2, mixing the first particles, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate, the second flour and the second water, granulating and drying to obtain the second particles; the amount of the second water is 10% of the mass of the second flour;

[0072] The mass ratio of the third flour, the first flour and the second flour is 0.2:1:3.8; the total amount of the third flour, the first flour and the second flour is the amount of flour in the sturgeon feed formula.

[0073] Example 6

[0074] The sturgeon feed of this embodiment is different from that of embodiment 3 only in that it further comprises 1% of Bacillus subtilis.

[0075] This embodiment also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0076] S1. According to the above ratio, Bacillus subtilis, the third flour and the third water are mixed, and granulated to obtain the third granules; the third granules, fish oil, soybean oil, choline, arachidonic acid, compound multi-dimensional, compound multi-mineral, the first flour and the first water are mixed, and granulated to obtain the first granules; the amount of the third water is 5% of the mass of the third flour, and the amount of the first water is 8% of the mass of the first flour;

[0077] S2, mixing the first particles, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate, the second flour and the second water, granulating and drying to obtain the second particles; the amount of the second water is 10% of the amount of the second flour;

[0078] The mass ratio of the third flour, the first flour and the second flour is 0.2:1:3.8; the total amount of the third flour, the first flour and the second flour is the amount of flour in the sturgeon feed formula.

[0079] Example 7

[0080] The sturgeon feed of this embodiment is different from that of embodiment 3 only in that it further comprises 2% gelatin.

[0081] This embodiment also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0082] S1. According to the above ratio, fish oil, soybean oil, choline, arachidonic acid, compound multivitamin, compound multi-mineral, first flour and first water are mixed and granulated to obtain first particles; the amount of the first water is 8% of the mass of the first flour; the gelatin solution is sprayed on the surface of the first particles and then dried to obtain the first particles coated with gelatin;

[0083] S2, mixing the first particles coated with gelatin, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate, the second flour and the second water to form granules, and then drying to obtain the second particles; the amount of the second water is 10% of the mass of the second flour;

[0084] The mass ratio of the first flour to the second flour is 1:4, and the total amount of the first flour and the second flour is the amount of flour in the sturgeon feed formula.

[0085] Example 8

[0086] The difference between the sturgeon feed of this embodiment and that of embodiment 7 is that the feed further comprises 1.5% of Bacillus subtilis.

[0087] This embodiment also provides a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0088] S1. According to the above ratio, Bacillus subtilis, the third flour and the third water are mixed to obtain the third particles, and the third particles, fish oil, soybean oil, choline, arachidonic acid, compound multivitamin, compound multi-mineral, the first flour and the first water are mixed, and granulated to obtain the first particles; the amount of the third water is 5% of the mass of the third flour, and the amount of the first water is 8% of the mass of the first flour; the gelatin solution is sprayed on the surface of the first particles, and then dried to obtain the first particles coated with gelatin on the surface;

[0089] S2, mixing the first particles coated with gelatin, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate, the second flour and the second water to form granules, and then drying to obtain the second particles; the amount of the second water is 10% of the mass of the second flour;

[0090] The mass ratio of the third flour, the first flour and the second flour is 0.2:1:3.8; the total amount of the third flour, the first flour and the second flour is the amount of flour in the sturgeon feed formula.

[0091] Comparative Example 1

[0092] The difference between this comparative example and Example 1 is that arachidonic acid is not contained. This example proposes a sturgeon feed, which, calculated by weight percentage, includes: 35% fish meal, 15% soybean meal, 10% chicken meal, 5% squid viscera powder, 4% fish oil, 4% soybean oil, 20.6% flour, 0.2% choline, 1.2% monocalcium phosphate, 1% compound multivitamin, 2% compound multimineral and 2% sodium carboxymethyl cellulose.

[0093] This comparative example also proposes a method for preparing the above-mentioned sturgeon feed, comprising the following steps:

[0094] Fish meal, soybean meal, chicken meal, squid viscera meal, flour, compound multivitamin, compound multi-mineral, choline, calcium dihydrogen phosphate and sodium carboxymethyl cellulose are mixed in a mixer, and then fish oil and soybean oil as well as water accounting for 15% of the total weight of each component are added to form a wet-based mixture, and the wet-based mixture is placed in a feed pellet machine and extruded to form cylindrical long strip particles, which are then dried in a cool and dry place and stored in a -20°C refrigerator for standby use.

[0095] Comparative Example 2

[0096] The difference between this comparative example and Example 8 is that the preparation method of the sturgeon feed is to directly mix the components to obtain the second particles, including the following steps:

[0097] S1. According to the proportions of each component in Example 8, all the components and water are mixed and granulated, and then dried to obtain the second granules.

[0098] Breeding experiment:

[0099] Before the experiment, 27 healthy Yangtze sturgeons with the same size and ovary stage III were selected by B-ultrasound and randomly divided into 3 groups. Each group was fed with the feed of Example 1, Example 2 and Comparative Example 1, and 9 fish in each group were cultured at 24.5 m 2 The elliptical cement pool has a water depth of 1.0m and an effective culture volume of 24.5m 3 The culture biomass is 4.77m3 / kg, the culture cycle is 12 months, feed is fed twice a day (feeding time is 8:00 and 20:00 respectively), the daily feeding rate is 0.6%, the culture water is underground deep well water, after aeration and sand filtration, it flows directly to the culture pond, and the flow rate is 0.132m / min. The sewage is discharged twice a day, 30 minutes before feeding, and the discharge volume accounts for about 1 / 5 of the total volume. The water temperature and dissolved oxygen are measured once a day, and the pH and ammonia nitrogen are measured once a week. The average water temperature during the culture period is 18.15℃, the water temperature range is 5.5℃~26.6℃, the average dissolved oxygen is 7.55mg / L, the dissolved oxygen range is 5.12mg / L~11.23mg / L, the pH is 7.91~8.15, and the ammonia nitrogen is 0.08~0.30mg / L.

[0100] Low temperature and flow rate creation measures: Based on the physiological characteristics of the Yangtze River sturgeon's development, a certain period of low temperature and flow rate stimulation is required. When the natural water temperature drops below 10°C, natural lake water is used for low temperature and flow rate stimulation to promote its development. In this study, the low temperature response time was 30 days, the water temperature range was 5.5-12.4°C, and the average water temperature was 8.72°C.

[0101] The flow rate is mainly created by pumping water into the culture pond with a submersible pump, and then transforming it into a high-pressure water flow with strong impact through the water outlet, thereby forming a large water flow on the surface water of the pond, so that a certain amount of micro-flow water is formed in the entire culture pond. In this study, the micro-flow water stimulation lasted for 30 days, which is consistent with the duration of low temperature.

[0102] Study Results

[0103] (1) Effects of arachidonic acid (ARA) on the growth and health status of female Yangtze sturgeon broodstock in stage III

[0104] Sturgeons with an initial average weight of 13.36±0.59kg were divided into 3 treatment groups, each with 9 test fish, a total of 27 female sturgeon broodstocks. The arachidonic acid feed was used to culture the III stage sturgeon broodstock for one year. The growth performance data of the test broodstock such as body length, weight gain rate, survival rate, and feed coefficient of different content of arachidonic acid in the feed were obtained, and the effect of ARA feed on the growth effect of sturgeon was evaluated. The results showed that the weight gain rate of the test fish in the 1% ARA group (Example 1) was the highest, significantly higher than that of the 0% ARA group (p<0.05) (Comparative Example 1), and there was no significant difference with the 2% ARA group (Example 2) (p>0.05). The weight gain rate had a downward trend with the increase of ARA content in the feed, and the feed coefficient of the 1% ARA group was the lowest. There was no significant difference in survival rate and terminal body weight among the groups (p>0.05). The specific results are shown in Table 1.

[0105] ②The inflammatory factor kit was used to determine the immune indicators such as TNF-α, IL-1β, IL-6, IL-8, IL-10, TGF-β1 in serum and mucus, and the effects of ARA feed on the health and immune function of sturgeon were evaluated. The results showed that there was no significant difference in blood IL-1β and IL-10 among the groups (p>0.05), and the blood TNF-α and TGF-β1 levels were highest in 1% ARA, significantly higher than those in 2% ARA group; the IL-6 content in 2% ARA group was significantly higher than that in 0% and 1% ARA groups (p<0.05); the IL-8 in 0% ARA group was significantly higher than that in 1% ARA group (p<0.05), and there was no significant difference between 0% ARA group and 2% ARA group (p>0.05). Mucus TNF-α and IL-1β were not affected by the ARA content in feed; the IL-10 and TGF-β1 contents were the highest in the 1% ARA group, significantly higher than that in the 0% ARA group, and the TGF-β1 content in the 2% ARA group was significantly higher than that in the 0% and 1% ARA groups; IL-6 showed an increasing trend with the increase of ARA content in feed, while IL-8 showed the opposite trend, the IL-6 content in the 0% ARA group was significantly lower than that in the 2% ARA group, and the IL-8 content in the 0% ARA group was significantly higher than that in the 2% ARA group. The specific results are shown in Table 2.

[0106] Table 1: Effects of arachidonic acid on growth performance and feed utilization of female Yangtze sturgeon broodstock in stage III

[0107]

[0108] Note: Data in the same row with different letters on their shoulders indicate significant differences (p<0.05), while data with the same letters or no letters indicate no significant differences (p>0.05). The number of replicates is n=9.

[0109] Table 2: Effects of arachidonic acid on serum and mucus inflammatory factors in female Yangtze sturgeon broodstock at stage III (pg / ml)

[0110]

[0111] Note: Different letters in the same row indicate significant differences (p<0.05), while the same or no letters indicate no significant differences (p

[0112] >0.05), where the number of replicates for blood was n=3 and for mucus was n=4.

[0113] Effects of arachidonic acid on hormone synthesis and egg development in female Yangtze sturgeon broodstock at stage III

[0114] One year after the sturgeon broodstock were fed with arachidonic acid feed, the ovarian development was monitored by B-ultrasound. At the same time, the blood of the experimental fish was collected and the serum sex hormones were measured. Combined with Table 3, the B-ultrasound monitoring results showed that the proportion of ovarian development to stage IV in the 1% ARA group was the highest, followed by the 2% ARA group, and the 0% ARA group was the lowest. The B-ultrasound monitoring results of the development of some broodstock are shown in Figure 1 It should be noted that in Example 2, the sexes of the two fish could not be distinguished, so only the proportion of the seven fish that developed into IV broodstock could be calculated, and six of the seven fish developed into IV broodstock.

[0115] Table 3: Effects of arachidonic acid on the developmental proportion of female Yangtze sturgeon broodstock in stage III

[0116]

[0117] Combination Figure 2 The results of blood sex hormones showed that the estradiol content in the 2% ARA group was the highest and the follicle-stimulating hormone content was the lowest; the testosterone content in the three groups was consistent; the luteinizing hormone content in the 1% ARA group was the highest.

[0118] On the basis of the above breeding experiments, we further optimized the scheme and used the feed prepared in Examples 3-8 and Comparative Example 2 to breed sturgeons. The breeding experimental method was the same as above, but the number of sturgeons in each group was increased to 15 in each group. After one year of breeding, the weight changes and egg development were detected. The results are shown in Tables 4, 5 and 6.

[0119] Table 4: Effects of Examples 3-6 on Growth Performance of Female Yangtze Sturgeon Parents in Stage III

[0120]

[0121] Table 5: Effects of Examples 7-8 and Comparative Example 2 on the Growth Performance of Female Yangtze Sturgeon Parents in Stage III

[0122]

[0123] Table 6: Effects of Examples 3-8 and Comparative Example 2 on the Development Ratio of Female Yangtze Sturgeon Parents in Stage III

[0124] Proportion of broodstock that develop to IV Example 3 93.33 Example 4 86.67 Example 5 93.33 Example 6 93.33 Example 7 100 Example 8 100 Comparative Example 2 86.67

[0125] Combined with Tables 4-6, it can be seen that the feeds prepared in Examples 3-8 can significantly increase the weight of sturgeons and develop to IV parent fish, which is higher than that in Examples 1-2; in particular, the feed prepared in Example 8 can increase the weight of sturgeons most significantly, and can develop 100% of stage III female sturgeons to IV parent fish.

[0126] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A sturgeon feed, characterized in that: The basic nutrients include protein, fat, vitamins and minerals, and are characterized in that, in the feed, arachidonic acid accounts for 0.1% to 2% of the weight percentage of the feed.

2. The sturgeon feed according to claim 1, characterized in that Calculated by weight percentage, it includes: 30%-40% fish meal, 10%-20% soybean meal, 10%-15% chicken meal, 5%-7% squid viscera powder, 3%-4% fish oil, 3%-4% soybean oil, 20%-25% flour, 0.1%-0.4% choline, 1%-1.5% monocalcium phosphate, 1%-2% compound multivitamin, 2%-3% compound multi-mineral, 2%-3% sodium carboxymethyl cellulose and 0.1%-2% arachidonic acid.

3. The sturgeon feed according to claim 1, characterized in that Calculated by weight percentage, the composition also includes 1%-1.5% probiotics.

4. The sturgeon feed according to claim 3, characterized in that The probiotics are Bacillus subtilis.

5. The sturgeon feed according to any one of claims 1 to 4, characterized in that: Also includes gelatin 1%-3%.

6. A method for preparing a sturgeon feed according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Mixing fish oil, soybean oil, choline, arachidonic acid, compound multivitamin, compound multimineral, first flour and water, and granulating to obtain first particles; S2, mixing the first particles, fish meal, soybean meal, chicken meal, squid viscera powder, sodium carboxymethyl cellulose, calcium dihydrogen phosphate and the second flour, granulating and drying to obtain the second particles.

7. The method for preparing sturgeon feed according to claim 6, characterized in that: In step S1, the process also includes mixing the probiotics and the third flour to obtain the third particles, and mixing the third particles, fish oil, soybean oil, choline, arachidonic acid, compound multivitamins, compound multiminerals, the second flour and water to obtain the first particles.

8. The method for preparing sturgeon feed according to claim 6 or 7, characterized in that: In step S1, it also includes spraying a gelatin solution on the surface of the first particles to obtain the first particles with the surface coated with gelatin.

9. The method for preparing sturgeon feed according to claim 6, characterized in that: In step S1, the mesh size of the first particles is 80-90 mesh.

10. A method for breeding sturgeons, characterized in that: The following steps are involved: Feeding the sturgeon feed according to any one of claims 1 to 5 or the sturgeon feed prepared by the preparation method according to any one of claims 6 to 9 twice a day, adopting flow-through culture, with a flow rate of 0.132-140 m 3 / min, the average water temperature during the breeding period is 18.15-18.5℃, the water temperature range is 5.5℃~26.6℃, the average dissolved oxygen is 7.55-8mg / L, the dissolved oxygen range is 5.12mg / L~11.23mg / L, the pH is 7.91~8.15, and the ammonia nitrogen is 0.08~0.30mg / L; When the water temperature drops below 10℃, natural lake water is used for low temperature and flow rate stimulation. The water temperature range is 5.5-12.4℃, and the average water temperature is 8.72-8.8℃.

Images