阅读说明：本技术 一种功能性饲料及其制备方法 (Functional feed and preparation method thereof ) 是由 缪凌鸿 高亮 林艳 张建桥 于丹 刘波 戈贤平 于 2021-08-30 设计创作，主要内容包括：本发明提供一种功能性饲料及其制备方法,所述功能性饲料主要由以下重量份的原料所制成：鱼粉1.0～2.5份、高生物利用率棉粕45～60份、豆粕10～15份、菜粕15～20份、小麦粉10～20份、豆油2.0～4.0份、磷酸二氢钙1.0～1.5份和复合预混料1.0～2.0份。本发明高生物利用率棉粕包括棉粕、复合营养补充添加剂、复合益生菌培养物添加剂和复合中草药提取物添加剂,各组分协同作用可有效增强淡水鱼类消化道物理屏障和营养物质吸收能力、提高胆汁的分泌和消化、肝脏的抗氧化解毒功能,促进鱼类营养感知和摄食行为,并且可促进棉粕营养物质的消化吸收,提高鱼类生长和饲料效率,提高养殖效益。(The invention provides a functional feed and a preparation method thereof, wherein the functional feed is mainly prepared from the following raw materials in parts by weight: 1.0-2.5 parts of fish meal, 45-60 parts of high-bioavailability cottonseed meal, 10-15 parts of soybean meal, 15-20 parts of rapeseed meal, 10-20 parts of wheat flour, 2.0-4.0 parts of soybean oil, 1.0-1.5 parts of monocalcium phosphate and 1.0-2.0 parts of compound premix. The cottonseed meal with high bioavailability comprises cottonseed meal, a composite nutrition supplement additive, a composite probiotic culture additive and a composite Chinese herbal medicine extract additive, and the components have synergistic effects of effectively enhancing the physical barrier of the alimentary canal of freshwater fish and the absorption capacity of nutrient substances, improving the secretion and digestion of bile and the antioxidation and detoxification functions of liver, promoting the nutrition perception and ingestion behavior of fish, promoting the digestion and absorption of nutrient substances of the cottonseed meal, improving the growth and feed efficiency of fish and improving the culture benefit.)

1. The functional feed is characterized by being mainly prepared from the following raw materials in parts by weight: 1.0-2.5 parts of fish meal, 45-60 parts of high-bioavailability cottonseed meal, 10-15 parts of soybean meal, 15-20 parts of rapeseed meal, 10-20 parts of wheat flour, 2.0-4.0 parts of soybean oil, 1.0-1.5 parts of monocalcium phosphate and 1.0-2.0 parts of compound premix;

the cottonseed meal with high bioavailability comprises 100-140 parts of cottonseed meal, 55-65 parts of composite nutrition supplement additive, 25-35 parts of composite probiotic culture additive and 5-15 parts of composite Chinese herbal medicine extract additive.

2. The functional feed according to claim 1, wherein the complex nutritional supplement additive comprises the following raw materials: 5-15 parts of ferrous sulfate, 10-20 parts of activated carbon, 15-25 parts of compound amino acid, 3-8 parts of choline chloride and 40-60 parts of bran; the composite probiotic culture additive comprises the following raw materials: 20-40 parts of freeze-dried lactic acid bacteria, 10-20 parts of Zhangzhou bacillus, 15-25 parts of butyric acid bacillus, 10-20 parts of saccharomycetes and 15-25 parts of aspergillus oryzae, wherein the composite Chinese herbal medicine extract additive comprises the following raw materials: 45-55 parts of ferulic acid, 25-35 parts of emodin and 15-25 parts of mulberry leaf polysaccharide.

3. The functional feed according to claim 2, wherein the freeze-dried lactic acid bacteria have a bacteria content of 4.1 x 10¹⁰~4.5×10¹⁰cfu/g, the bacterial content of the Zhangzhou bacillus is 5.4 multiplied by 10¹⁰~5.8×10¹⁰cfu/g, the bacterium content of the bacillus casei is 3.4 multiplied by 10¹⁰~4.1×10¹⁰cfu/g, the bacteria content of the yeast is 3.1 multiplied by 10¹⁰~3.6×10¹⁰cfu/g, the bacterium content of the aspergillus oryzae is 2.7 multiplied by 10⁹~3.3×10⁹cfu/g。

4. The functional feed as claimed in claim 2, wherein the compound amino acid is mainly prepared from the following raw materials in parts by weight: 12-18 parts of L-lysine, 4-8 parts of L-methionine, 6-14 parts of L-phenylalanine, 6-15 parts of L-isoleucine, 16-25 parts of L-leucine, 6-12 parts of L-valine, 6-12 parts of L-threonine, 12-18 parts of L-arginine and 3-8 parts of L-histidine.

5. A preparation method of a functional feed is characterized by comprising the following steps:

(1) uniformly mixing 5-15 parts of ferrous sulfate, 10-20 parts of activated carbon, 15-25 parts of compound amino acid, 3-8 parts of choline chloride and 40-60 parts of bran according to a weight ratio to prepare a compound nutrition supplement additive; uniformly mixing 20-40 parts of freeze-dried lactic acid bacteria, 10-20 parts of Zhangzhou bacillus, 15-25 parts of butyric acid bacillus, 10-20 parts of saccharomycetes and 15-25 parts of aspergillus oryzae according to a weight ratio to prepare a composite probiotic culture additive;

(2) respectively carrying out superfine grinding and sieving on ferula asafetida, rheum officinale and mulberry leaves, adding distilled water to prepare 15-20% suspension, carrying out water bath reflux extraction, carrying out ethanol precipitation on an extracting solution, carrying out extraction filtration on the extracting solution, carrying out freeze drying at-18 ℃ for 18-20 hours to obtain ferulic acid, emodin and mulberry leaf crude polysaccharide powder, respectively, and mixing 45-55 parts of ferulic acid, 25-35 parts of emodin and 15-25 parts of mulberry leaf polysaccharide according to a weight ratio to obtain a composite Chinese herbal medicine extract additive;

(3) fully and uniformly mixing 100-140 parts of cottonseed meal and 55-65 parts of composite nutrition supplement additive for 10 minutes at room temperature, and standing for 36-48 hours at 30-35 ℃ under aerobic condition;

(4) fully and uniformly mixing 25-35 parts of composite probiotic culture additive and the mixture obtained in the step (3) for 10 minutes at room temperature, adding 25-35% of distilled water, and standing for 4-6 days at 30-35 ℃ under a closed anaerobic condition;

(5) fully and uniformly mixing 5-15 parts of the composite Chinese herbal medicine extract additive and the mixture obtained in the step (4) for 10 minutes at room temperature to obtain cottonseed meal with high bioavailability;

(6) 1.0-2.5 parts of fish meal, 45-60 parts of cottonseed meal with high bioavailability, 10-15 parts of soybean meal and 15-20 parts of rapeseed meal are crushed and sieved, and are stirred and mixed with 10-20 parts of wheat flour, 1.0-1.5 parts of monocalcium phosphate and 1.0-2.0 parts of compound premix for 10 minutes at room temperature, 2.0-4.0 parts of soybean oil is added, and the mixture is stirred and mixed for 10 minutes at room temperature and then is extruded and granulated in a flat-grinding extrusion granulator to obtain the functional feed.

Technical Field

The invention relates to the technical field of feed in aquaculture, in particular to a functional feed and a preparation method thereof.

Background

The feed cost of the aquaculture industry accounts for about 70 percent of the total culture cost, and the feed is mainly protein raw materials. With the rising of the prices of protein sources such as fish meal, bean pulp and the like, the breeding cost is directly and rapidly increased. Nowadays, the protein source with high quality and low price can be replaced to become a main object for research in the feed nutrition industry. The cottonseed meal is used as a byproduct of cottonseed oil pressing, the content of crude protein of the cottonseed meal can reach more than 45 percent, and the cottonseed meal is a high-quality low-price plant protein source. In addition, the yield in China is large, the yield of the cotton seeds in China, which is the first major country for producing cotton, accounts for 1/4 of the total yield in the world, is more than 1100 million tons in 2018, and the cottonseed meal is 600 million tons, but the application of the cottonseed meal in aquatic animal feed is limited due to the fact that the cottonseed meal contains anti-nutritional factors such as free gossypol, cyclopropene fatty acid, phytic acid, tannin and the like, and particularly the free gossypol in the cottonseed meal can cause adverse effects on the growth and the immunity of aquatic animals. A great deal of research shows that the feed with high content of free gossypol can adversely affect the growth and immunity of aquatic animals such as crucian, porgy, turbot, black carp, grass carp, tilapia, eriocheir sinensis and the like, and can affect the muscle quality of the cultured animals, thereby causing the muscle residue of the free gossypol.

In order to improve the utilization rate of the cottonseed meal, a great deal of research is carried out on the detoxification technology of the cottonseed meal in recent years, the main means is to reduce the content of antinutritional factors in the cottonseed meal by physical, chemical and biological methods, wherein the physical method comprises high-temperature treatment, radiation technology and puffing treatment, and the chemical method comprises Fe²⁺Treatment, alkali neutralization and oxidation treatment, and biological methods refer to microbial fermentation and enzymolysis.

Gossypol has the property of dibasic acid, and is extremely easy to combine with divalent metal ions to form non-toxic combined gossypol, while Fe²⁺Can be combined with gossypol in the molar mass ratio of 1:1 to achieve the detoxication effect of the cottonseed meal. The ferrous sulfate detoxification method has low cost and convenient operation, and is a well-known detoxification method. But for added Fe²⁺The amount of (A) needs to be further studied, Fe²⁺Although the content of free gossypol in the cottonseed meal can be reduced, the palatability is reduced due to excessive addition, meanwhile, the divalent iron can also chelate lysine and the like to reduce the nutritional value of the feed and generate negative effects on cultured animals, and Fe at present²⁺The research on the application of the cottonseed meal detoxification technology to aquatic animals is few, and the main research object is livestock and poultry.

The fermented cottonseed meal is a feed raw material which takes cottonseed meal as a main raw material, reduces the content of various anti-nutritional factors in the cottonseed meal by using a microbial fermentation technology, and simultaneously generates nutrient substances such as small peptides, amino acids, organic acids, vitamins and the like by using the growth metabolic activity of beneficial microorganisms, so that the method not only can reduce the toxic effect of free gossypol, but also can improve the nutritional value of the cottonseed meal; the fermented cottonseed meal has high protein content and contains a large amount of probiotics and digestive enzymes, so the fermented cottonseed meal has great application potential in aquatic animal culture, and has been studied in freshwater animals such as black carp, crucian carp, eriocheir sinensis and the like. However, due to the complexity of the fermentation microorganisms and the metabolites thereof, the fermentation effect of some probiotics is also found to be not ideal, and even the animal production performance is affected, so that the search for an effective fermentation probiotic compatibility and a fermentation and addition technology thereof is very important.

Therefore, the content of the invention is optimized and improved mainly aiming at the technical and application defects existing in the preparation of detoxified cottonseed meal by physics and microorganisms, and the synergistic combined action of the composite nutrition supplement additive, the probiotic culture additive and the composite Chinese herbal medicine extract additive is adopted to realize the purposes of effectively promoting the digestion and absorption of cottonseed meal nutrient substances, enhancing the physical barrier of the alimentary canal of freshwater fish and the absorption capacity of nutrient substances, improving the secretion and digestion of bile and the antioxidation and detoxification functions of liver, promoting the nutrition perception and ingestion behaviors of fish, and achieving the purpose of improving the bioavailability of cottonseed meal, thereby reducing the feed ingredients and improving the culture economic benefit.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a functional feed and a preparation method thereof. The functional feed is applied to the functional feed for freshwater fish, the cottonseed meal with high bioavailability comprises cottonseed meal, a compound nutrition supplement additive, a compound probiotic culture additive and a compound Chinese herbal medicine extract additive, and the additive has synergistic effect to effectively promote the digestion and absorption of nutrient substances of the cottonseed meal, enhance the physical barrier of the alimentary tract of freshwater fish and the absorption capacity of the nutrient substances, improve the secretion and digestion of bile, and the anti-oxidation and detoxification functions of liver, and promote the nutrition perception and ingestion behavior of the fish; the additive can improve the adding proportion of the cottonseed meal in the freshwater fish compound feed, reduce the toxic action of anti-nutritional factors in the cottonseed meal, promote the nutrient absorption efficiency of the cottonseed meal into the feed, reduce the feed ingredients and improve the breeding benefit.

The technical scheme adopted by the invention is as follows:

a functional feed is mainly prepared from the following raw materials in parts by weight: 1.0-2.5 parts of fish meal, 45-60 parts of high-bioavailability cottonseed meal, 10-15 parts of soybean meal, 15-20 parts of rapeseed meal, 10-20 parts of wheat flour, 2.0-4.0 parts of soybean oil, 1.0-1.5 parts of monocalcium phosphate and 1.0-2.0 parts of compound premix;

the cottonseed meal with high bioavailability comprises 100-140 parts of cottonseed meal, 55-65 parts of composite nutrition supplement additive, 25-35 parts of composite probiotic culture additive and 5-15 parts of composite Chinese herbal medicine extract additive.

The compound premix comprises a vitamin and mineral mixture, and each kilogram of the compound premix comprises: 10mg vitamin B1, 20mg vitamin B2, 30mg vitamin B6, 0.02mg vitamin B12, 5mg folic acid, 50mg calcium pantothenate, 100mg inositol, 100mg niacin, 0.5mg vitamin H, 100mg vitamin C, 110mg vitamin A, 20mg vitamin D, 100mg vitamin E, 10mg vitamin K; 15g magnesium sulfate, 2.5g ferrous sulfate, 31mg copper sulfate, 162mg manganese sulfate, 353mg zinc sulfate, 3mg potassium iodate, 3mg sodium selenate and 1mg cobalt sulfate.

Preferably, the functional feed, wherein the composite nutritional supplement additive comprises the following raw materials: 5-15 parts of ferrous sulfate, 10-20 parts of activated carbon, 15-25 parts of compound amino acid, 3-8 parts of choline chloride and 40-60 parts of bran; the composite probiotic culture additive comprises the following raw materials: 20-40 parts of freeze-dried lactic acid bacteria, 10-20 parts of Zhangzhou bacillus, 15-25 parts of butyric acid bacillus, 10-20 parts of saccharomycetes and 15-25 parts of aspergillus oryzae, wherein the composite Chinese herbal medicine extract additive comprises the following raw materials: 45-55 parts of ferulic acid, 25-35 parts of emodin and 15-25 parts of mulberry leaf polysaccharide.

Preferably, the functional feed, wherein the freeze-dried lactic acid bacteria have a bacteria content of 4.1 × 10¹⁰～4.5×10¹⁰cfu/g, the bacterial content of the Zhangzhou bacillus is 5.4 multiplied by 10¹⁰～5.8×10¹⁰cfu/g, the bacterium content of the bacillus casei is 3.4 multiplied by 10¹⁰～4.1×10¹⁰cfu/g, the bacteria content of the yeast is 3.1 multiplied by 10¹⁰～3.6×10¹⁰cfu/g, the bacterium content of the aspergillus oryzae is 2.7 multiplied by 10⁹～3.3×10⁹cfu/g。

Preferably, the functional feed is prepared from the following raw materials in parts by weight: 12-18 parts of L-lysine, 4-8 parts of L-methionine, 6-14 parts of L-phenylalanine, 6-15 parts of L-isoleucine, 16-25 parts of L-leucine, 6-12 parts of L-valine, 6-12 parts of L-threonine, 12-18 parts of L-arginine and 3-8 parts of L-histidine.

A preparation method of a functional feed is characterized by comprising the following steps:

(1) uniformly mixing 5-15 parts of ferrous sulfate, 10-20 parts of activated carbon, 15-25 parts of compound amino acid, 3-8 parts of choline chloride and 40-60 parts of bran according to a weight ratio to prepare a compound nutrition supplement additive; uniformly mixing 20-40 parts of freeze-dried lactic acid bacteria, 10-20 parts of Zhangzhou bacillus, 15-25 parts of butyric acid bacillus, 10-20 parts of saccharomycetes and 15-25 parts of aspergillus oryzae according to a weight ratio to prepare a composite probiotic culture additive;

(2) respectively carrying out superfine grinding and sieving on ferula asafetida, rheum officinale and mulberry leaves, adding distilled water to prepare 15-20% suspension, carrying out water bath reflux extraction, carrying out ethanol precipitation on an extracting solution, carrying out extraction filtration on the extracting solution, carrying out freeze drying at-18 ℃ for 18-20 hours to obtain ferulic acid, emodin and mulberry leaf crude polysaccharide powder respectively, and mixing 45-55 parts of ferulic acid, 25-35 parts of emodin and 15-25 parts of mulberry leaf polysaccharide according to the weight ratio to obtain a composite Chinese herbal medicine extract additive;

(3) fully and uniformly mixing 100-140 parts of cottonseed meal and 55-65 parts of composite nutrition supplement additive for 10 minutes at room temperature, and standing for 36-48 hours at 30-35 ℃ under aerobic condition;

(4) fully and uniformly mixing 25-35 parts of composite probiotic culture additive and the mixture obtained in the step (3) for 10 minutes at room temperature, adding 25-35% of distilled water, and standing for 4-6 days at 30-35 ℃ under a closed anaerobic condition;

(5) fully and uniformly mixing 5-15 parts of the composite Chinese herbal medicine extract additive and the mixture obtained in the step (4) for 10 minutes at room temperature to obtain cottonseed meal with high bioavailability;

(6) 1.0-2.5 parts of fish meal, 45-60 parts of cottonseed meal with high bioavailability, 10-15 parts of soybean meal and 15-20 parts of rapeseed meal are crushed and sieved, and then the crushed and sieved fish meal, 10-20 parts of wheat flour, 1.0-1.5 parts of monocalcium phosphate and 1.0-2.0 parts of compound premix are stirred and mixed for 10 minutes at room temperature, soybean oil is added, the mixture is stirred and mixed for 10 minutes at room temperature again, and then the mixture is extruded and granulated in a flat-grinding extrusion granulator to obtain the functional feed.

The invention has the advantages that:

the functional feed disclosed by the invention has the advantages that the cottonseed meal with high bioavailability comprises cottonseed meal, a composite nutrition supplement additive, a composite probiotic culture additive and a composite Chinese herbal medicine extract additive, the physical barrier of the alimentary canal and the nutrient absorption capacity of freshwater fish can be effectively enhanced, the secretion and digestion of bile and the antioxidation and detoxification functions of liver can be improved, the nutrition perception and ingestion behaviors of fish can be promoted, the additive can promote the digestion and absorption of nutrient substances of the cottonseed meal, the growth and feed efficiency of fish can be improved when the additive is applied to the freshwater fish feed, and the culture benefit can be improved.

Drawings

FIG. 1 is a transmission electron micrograph of intestinal microvilli of each group in example 3 of the present invention.

FIG. 2 is a table of the results of the data of the cumulative mortality rate after intraperitoneal injection of each group of pathogenic bacteria in example 6 of the present invention.

Detailed Description

The present invention will be further described with reference to the following specific examples.

Lyophilized lactobacillus ZJY 6 (with the preservation number of CCTCC NO: M2014579, Bacillus Zhangzhou JSSW-BP44 (with the preservation number of CCTCC NO: M2019989), Bacillus casei JSIMM-MCB 20040312 (with the preservation number of CGMCC NO:1647), saccharomycete (with the preservation number of CICC 1421) and Aspergillus oryzae TA20 (with the preservation number of CCTCC NO: M2016602).

Example 1

A feed additive comprises, by weight, 60 parts of a composite nutrition supplement additive, 30 parts of a composite probiotic culture additive and 10 parts of a composite Chinese herbal medicine extract additive;

the preparation method of the cottonseed meal with high bioavailability comprises the following steps:

(1) 60g of composite nutrition supplement additive is prepared by mixing according to the weight ratio, and comprises 6g of ferrous sulfate, 9g of active carbon, 12g of composite amino acid, 3g of choline chloride and 30g of bran. Wherein the weight ratio of the composite amino acid composition is 1.92g of L-lysine, 0.6g of L-methionine, 1.44g of L-phenylalanine, 0.96g of L-isoleucine, 2.16g of L-leucine, 1.2g of L-valine, 1.2g of L-threonine, 1.8g of L-arginine and 0.72g of L-histidine;

(2) mixing the components according to a weight ratio to prepare 30g of composite probiotic culture additive, which mainly comprises 9g of freeze-dried lactic acid bacteria, 4.5g of Zhangzhou bacillus, 6g of butyric acid bacillus, 4.5g of saccharomycetes and 6g of Aspergillus oryzae; weighing 10g of compound Chinese herbal medicine extract additive, wherein the compound Chinese herbal medicine extract additive mainly comprises 5g of ferulic acid, 3g of emodin and 2g of mulberry leaf polysaccharide.

(3) After preparing each composite additive component, weighing 100g of cottonseed meal and 60g of composite nutrition supplement additive, fully stirring and uniformly mixing, putting into a transparent plastic fermentation bag with the volume of 5L, and standing for 36 hours at the temperature of 32 ℃ with an opening;

(4) mixing uniformly and standing for 36 hours, adding 30g of the weighed composite probiotic culture additive into a 5L fermentation bag, fully stirring and mixing uniformly, slowly spraying 60ml of distilled water by using a spray can, kneading and mixing uniformly while spraying, sealing by using a thermoplastic sealing machine, standing at 35 ℃ for 5 days in a sealed manner, shaking the mixture at random to avoid agglomeration or formation of coated particles; the content of lyophilized lactobacillus in the mixture is 2.1 × 10⁸The bacterial content of the bacillus Zhangzhou and the bacillus Zhang is 2.8 multiplied by 10⁸cfu, the bacteria content of the bacillus casei is 1.8 multiplied by 10⁸cfu, yeast content 1.7 × 10⁸cfu and Aspergillus oryzae content of 1.5 × 10⁷cfu；

(5) And (3) after the mixture is placed in a closed state for fermentation for 5 days, carefully opening a fermentation bag, adding the weighed 10g of the composite Chinese herbal medicine extract additive, and fully stirring and uniformly mixing the mixture again to prepare the cottonseed meal with high bioavailability.

The content of free gossypol in the cottonseed meal raw material and the cottonseed meal with high bioavailability is detected, and the data is as follows:

free gossypol content, mg/kg	Cottonseed meal before treatment	Treated cotton dregs	Rate of detoxification
				Sample No. 1	1385.38	492.65	64.44％
Sample No. 2	1339.87	481.63	64.05％
				Sample No. 3	1409.51	596.41	57.69％
Mean value of	1378.25	523.56	62.06％

Example 2

The high-bioavailability cottonseed meal prepared in example 1 was used to prepare a conventional freshwater fish compound feed and a test freshwater fish compound feed, and the formula was as follows:

control (addition of untreated cottonseed meal): 5.3 percent of fish meal, 21.6 percent of soybean meal, 16.2 percent of rapeseed meal, 16.3 percent of cottonseed meal, 4.2 percent of concentrated cottonseed protein, 17.7 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of monocalcium phosphate, 1 percent of premix, 0.5 percent of choline chloride, 1.5 percent of microcrystalline cellulose and 0.7 percent of bentonite.

High cottonseed meal group (addition of untreated cottonseed meal): 5.3 percent of fish meal, 6.5 percent of soybean meal, 45.5 percent of cottonseed meal, 8.5 percent of concentrated cottonseed protein, 17.7 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of calcium dihydrogen phosphate and 1.5 percent of microcrystalline cellulose.

Test group 1 (addition of high bioavailability cottonseed meal): 5.3 percent of fish meal, 6.5 percent of soybean meal, 45.5 percent of cottonseed meal with high bioavailability, 8.5 percent of concentrated cottonseed protein, 17.7 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of monocalcium phosphate and 1.5 percent of microcrystalline cellulose.

Test group 2 (addition of high bioavailability cottonseed meal): 3.5 percent of fish meal, 6.5 percent of soybean meal, 55.5 percent of cottonseed meal with high bioavailability, 6.5 percent of concentrated cottonseed protein, 11.5 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of monocalcium phosphate and 1.5 percent of microcrystalline cellulose.

The raw materials in the feed formula are crushed, sieved and mixed step by step to be prepared into sinking pellet feed for feeding the megalobrama amblycephala through a granulator. The megalobrama amblycephala juvenile fish (5.00 +/-0.00 g) with unified physique health specification is randomly distributed into 9 net cages (1m multiplied by 1m), 20 tail parts of each net cage are fed with a test feed through three net cages randomly, the test feed is fed for three times every day, the feeding is respectively 8:00, 11:00 and 17:00, and the feeding is carried out for eight weeks in total. During the test, the water temperature is kept between 20 and 28 ℃, the dissolved oxygen content is more than or equal to 6mg/L, the ammonia nitrogen content is less than or equal to 0.2mg/L, the nitrite content is less than or equal to 0.2mg/L, the pH value is kept between 6.8 and 7.5, and the illumination time is about 12 h/d. Megalobrama amblycephala growth performance was measured after 8 weeks, and growth data were tested for normality (Shapiro-Wilk test) and homogeneity of variance (Leven test) followed by One-way ANOVA (One-way ANOVA) using sps 22.0 software (IBM, USA). The Duncan test was used to compare the differences in the mean values, with significant differences being considered for P < 0.05. Data results are shown in table 1:

TABLE 1

From the growth data in table 1, it can be seen that the growth performance of the megalobrama amblycephala feed added with 45.5% and 55.5% of cottonseed meal with high bioavailability is significantly higher than that of the megalobrama amblycephala feed added with high dose of conventional cottonseed meal, and the growth performance is not significantly different from that of the conventional compound feed.

Example 3

The high-bioavailability cottonseed meal prepared in example 1 was used to prepare a conventional freshwater fish compound feed and a test freshwater fish compound feed, and the formula was as follows:

control (addition of untreated cottonseed meal): 5.3 percent of fish meal, 21.6 percent of soybean meal, 16.2 percent of rapeseed meal, 16.3 percent of cottonseed meal, 4.2 percent of concentrated cottonseed protein, 17.7 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of monocalcium phosphate, 1 percent of premix, 0.5 percent of choline chloride, 1.5 percent of microcrystalline cellulose and 0.7 percent of bentonite.

High cottonseed meal group (addition of untreated cottonseed meal): 5.3 percent of fish meal, 6.5 percent of soybean meal, 45.5 percent of cottonseed meal, 8.5 percent of concentrated cottonseed protein, 17.7 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of calcium dihydrogen phosphate and 1.5 percent of microcrystalline cellulose.

Test group 1 (addition of high bioavailability cottonseed meal): 5.3 percent of fish meal, 6.5 percent of soybean meal, 45.5 percent of cottonseed meal with high bioavailability, 8.5 percent of concentrated cottonseed protein, 17.7 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of monocalcium phosphate and 1.5 percent of microcrystalline cellulose.

Test group 2 (addition of high bioavailability cottonseed meal): 3.5 percent of fish meal, 6.5 percent of soybean meal, 55.5 percent of cottonseed meal with high bioavailability, 6.5 percent of concentrated cottonseed protein, 11.5 percent of wheat flour, 12 percent of rice bran, 2 percent of soybean oil, 1 percent of monocalcium phosphate and 1.5 percent of microcrystalline cellulose.

The raw materials in the feed formula are crushed, sieved and mixed step by step to be prepared into sinking pellet feed for feeding the megalobrama amblycephala through a granulator. The megalobrama amblycephala juvenile fish (5.00 +/-0.00 g) with unified physique health specification is randomly distributed into 9 net cages (1m multiplied by 1m), 20 tails of each net cage are fed with a test feed through three net cages randomly, the feed is fed for three times every day, the feed is respectively 8:00, 11:00 and 17:00, the feed is fed for eight weeks totally, during the test period, the water temperature is kept between 20 and 28 ℃, the dissolved oxygen content is more than or equal to 6mg/L, the ammonia nitrogen content is less than or equal to 0.2mg/L, the nitrite content is less than or equal to 0.2mg/L, the pH value is kept between 6.8 and 7.5, and the growth is about 12h/d during illumination; intestinal tissue samples of megalobrama amblycephala are collected after 8 weeks, fixed in 2.5% glutaraldehyde, and analyzed by a transmission electron microscope, and the results are shown in figure 1.

As can be seen from the transmission electron microscope of intestinal microvilli in FIG. 1, the rupture of the microvilli tissue structure in the intestinal tract of the high-cottonseed-meal group fish is obvious, part of microvilli in the intestinal tract of the control group fish is broken and staggered in structure, and the microvilli in the intestinal tracts of the test groups 1 and 2 are arranged neatly and tightly and structurally, which indicates that the high-bioavailability cottonseed meal used in the test groups has the effect of strengthening the intestinal tissue structure and the digestion and absorption capacity of the freshwater fish.

Example 4

A feed additive comprises 65 parts by weight of composite nutrition supplement additive, 28 parts by weight of composite probiotic culture additive and 7 parts by weight of composite Chinese herbal medicine extract additive;

the preparation method of the cottonseed meal with high bioavailability comprises the following steps:

(1) 65g of composite nutrition supplement additive is prepared by mixing according to the weight ratio, and comprises 11g of ferrous sulfate, 6g of active carbon, 15g of composite amino acid, 5g of choline chloride and 28g of bran. Wherein the weight ratio of the composite amino acid composition is 2.5g of L-lysine, 1.2g of L-methionine, 1.5g of L-phenylalanine, 1.4g of L-isoleucine, 2.5g of L-leucine, 1.2g of L-valine, 1.5g of L-threonine, 2.2g of L-arginine and 1.0g of L-histidine;

(2) mixing according to a weight ratio to prepare 28g of composite probiotic culture additive, which mainly comprises 10g of freeze-dried lactic acid bacteria, 5g of Zhangzhou bacillus, 4.5g of butyric acid bacillus, 2.8g of saccharomycetes and 5.7g of aspergillus oryzae; weighing 7g of compound Chinese herbal medicine extract additive, wherein the compound Chinese herbal medicine extract additive mainly comprises 3.2g of ferulic acid, 2.4g of emodin and 1.4g of mulberry leaf polysaccharide.

(3) After preparing each composite additive component, weighing 140g of cottonseed meal and 65g of composite nutrition supplement additive, fully stirring and uniformly mixing, putting into a transparent plastic fermentation bag with the volume of 5L, and standing for 48 hours at the temperature of 35 ℃ with an opening;

(4) mixing, standing for 48 hr, adding 28g of the composite probiotic culture additive into 5L fermentation bag, stirring,slowly spraying 70ml of distilled water with a spraying pot, kneading and uniformly mixing while spraying, so that the mixture is free from agglomeration and particles, sealing with a thermoplastic sealing machine, and standing at 35 ℃ for 6 days in a sealed manner, wherein the mixture is shaken at random to avoid agglomeration or formation of coated particles; the content of lyophilized lactobacillus in the mixture is 1.6 × 10⁹The bacterial content of the bacillus Zhangzhou and the bacillus Zhang is 1.1 multiplied by 10⁹cfu, the bacteria content of the bacillus tyrosinus is 6.2 multiplied by 10⁸cfu, yeast content of 3.2 × 10⁸cfu and Aspergillus oryzae content of 6.8 × 10⁷cfu；

(5) And (3) after the mixture is placed in a closed state for fermentation for 5 days, carefully opening a fermentation bag, adding the weighed 7g of the composite Chinese herbal medicine extract additive, and fully stirring and uniformly mixing the mixture again to prepare the cottonseed meal with high bioavailability.

The content of free gossypol in the cottonseed meal raw material and the cottonseed meal with high bioavailability is detected, and the data is as follows:

free gossypol content, mg/kg	Cottonseed meal before treatment	Treated cotton dregs	Rate of detoxification
				Sample No. 1	1366.54	387.66	71.63％
Sample No. 2	1301.88	405.15	68.88％
				Sample No. 3	1339.62	411.08	69.31％
Mean value of	1336.01	401.3	69.94％

Example 5

The high-bioavailability cottonseed meal prepared in example 4 was used to prepare a conventional freshwater fish compound feed and a test freshwater fish compound feed, and the formula was as follows:

control (addition of untreated cottonseed meal): 1% of fish meal, 20% of soybean meal, 15% of rapeseed meal, 15% of cottonseed meal, 15% of wheat flour, 12% of rice bran, 10% of wheat bran, 2% of soybean oil, 2% of monocalcium phosphate, 1% of premix, 1% of choline chloride, 5% of microcrystalline cellulose and 1% of bentonite.

High cottonseed meal group (addition of untreated cottonseed meal): 16% of soybean meal, 45% of cottonseed meal, 15% of wheat flour, 12% of rice bran, 2% of soybean oil, 2% of monocalcium phosphate, 1% of premix, 1% of choline chloride, 5% of microcrystalline cellulose and 1% of bentonite.

Test group (addition of high bioavailability cottonseed meal): 16% of soybean meal, 45% of cotton meal with high bioavailability, 15% of wheat flour, 12% of rice bran, 2% of soybean oil, 2% of monocalcium phosphate, 1% of premix, 1% of choline chloride, 5% of microcrystalline cellulose and 1% of bentonite.

The raw materials in the feed formula are crushed, sieved and mixed step by step, and then are prepared into sinking granular feed through a granulator to feed the grass carp. Young grass carp (13.32 +/-1.50 g) with unified physique health specifications are randomly distributed into 9 net cages (1m multiplied by 1m), 30 fish in each net cage are fed with a test feed through three net cages randomly, the feeding is carried out three times every day, the feeding is respectively 8:00, 11:00 and 17:00, and the feeding is carried out for 12 weeks in total. During the test, the water temperature is kept between 20 and 28 ℃, the dissolved oxygen content is more than or equal to 6mg/L, the ammonia nitrogen content is less than or equal to 0.2mg/L, the nitrite content is less than or equal to 0.2mg/L, the pH value is kept between 6.8 and 7.5, and the illumination time is about 12 h/d. Grass carp growth performance and liver health status were determined after 8 weeks, and growth data were tested for normality (Shapiro-Wilk test) and homogeneity of variance (Leven test) and then analyzed for One-way ANOVA (One-way ANOVA) using sps 22.0 software (IBM, USA). Tukey's test was used to compare the difference in mean values, with P < 0.05 being considered as a significant difference. Data results are shown in table 2:

TABLE 2

Growth index	Control group	High cottonseed meal group	Test group
				Average weight at end (g/tail)	117.21±1.96b	108.26±2.08a	119.18±1.82b
Weight gain (%)	746.38±2.45ab	705.25±19.65a	783.83±10.23b
				Specific growth Rate (% day)-1)	3.81±0.00ab	3.32±0.04a	3.89±0.02b
Coefficient of bait	1.41±0.00ab	1.52±0.06b	1.36±0.01a
Biochemical index of blood	Control group	High cottonseed meal group	Test group
				Glutamic-pyruvic transaminase (U/L)	5.38±0.67ab	9.41±0.92c	3.89±0.54a
Glutamic-oxalacetic transaminase (U/L)	83.91±7.08ab	111.18±22.53b	79.52±4.76a
				Alkaline phosphatase (U/L)	13.81±0.81a	20.44±1.70b	14.35±1.19a
Lactate dehydrogenase (U/L)	504.64±30.24ab	635.73±21.31b	411.03±36.69a
Liver oxidation resistance index	Control group	High cottonseed meal group	Test group
				Catalase (U/gprot)	16.8±1.84ab	13.05±0.98a	19.93±1.75b
Superoxide dismutase (U/gprot)	0.73±0.09ab	0.64±0.04a	1.02±0.1b
				Malondialdehyde (mmol/gprot)	0.24±0.02a	0.61±0.0b	0.35±0.06a
Lysozyme activity (U/gprot)	1.24±0.28ab	0.93±0.35a	2.26±0.36b

From the growth data in table 2, it can be seen that the growth performance of the grass carp juvenile feed added with 45% of the cottonseed meal with high bioavailability is significantly higher than that of the conventional cottonseed meal with high dosage, and the growth performance is not significantly different from that of the conventional compound feed.

The contents of glutamic-pyruvic transaminase, glutamic-oxalacetic transaminase, alkaline phosphatase and lactate dehydrogenase in blood can be reflected in the metabolic function of the liver of a fish body and the physiological health state of blood. From the blood biochemical data in table 2, it can be seen that the contents of glutamic-pyruvic transaminase, glutamic-oxalacetic transaminase, alkaline phosphatase and lactate dehydrogenase in blood after adding 45% of the cottonseed meal with high bioavailability to the feed for young grass carps are significantly lower than those of the conventional cottonseed meal with high dosage, and have no significant difference with the conventional compound feed.

From the liver antioxidant data in table 2, it can be seen that the activities of liver catalase, superoxide dismutase and lysozyme after adding 45% of the cottonseed meal with high bioavailability to the young grass carp feed are significantly higher than those of the conventional cottonseed meal with high dosage, and are not significantly different from those of the conventional compound feed. On the other hand, the content of the malondialdehyde in the liver is changed in an opposite way, and the cottonseed meal group with high bioavailability added by 45% is obviously lower than the cottonseed meal group with high bioavailability, and has no obvious difference with the conventional compound feed group.

The above results show that the feed added with 45% of cottonseed meal with high bioavailability can remarkably relieve growth inhibition and oxidative damage caused by high-level cottonseed meal content, remarkably improve liver metabolism and antioxidant function, and improve the physiological level of health of organisms.

Example 6

Eight weeks after the young grass carp is cultured in the experimental grass carp of example 5, 20 grass carp are randomly selected from each net cage according to the ratio of 2X 10⁷Intraperitoneal injection of cfu/g body weight is carried out on pathogenic bacteria aeromonas hydrophila, the mortality of the grass carp is counted at 0h (before injection), 6h, 12h, 1d, 2d, 3d, 4d, 5d, 6d and 7d after toxin counteracting treatment, and the accumulated mortality is calculated. The results are shown in FIG. 2.

From the data result of the accumulated mortality after pathogen intraperitoneal injection in fig. 2, the accumulated mortality of grass carp in a high-cottonseed-meal group after 7 days of pathogen infection reaches 80.0%, the accumulated mortality of grass carp in a control group after 7 days of pathogen infection reaches 47.5%, and the accumulated mortality of grass carp in a test group after 7 days of pathogen infection is obviously reduced to 23.3%, which shows that the high-bioavailability cottonseed meal used in the test group has the effect of enhancing the pathogenic bacteria infection resistance of grass carp, enhancing the health state of fish body and improving the survival rate.

Finally, it should be noted that the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to examples, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.