A compound feed for freshwater fish and its preparation method

Abstract

The present invention provides a compound feed for freshwater fish and a preparation method thereof, comprising the following raw materials in parts by weight: 39-44 parts of corn protein powder, 22-34 parts of cottonseed protein powder, 5.4-9.2 parts of black soldier fly larva powder, 11-23 parts of fish oil, 20-30 parts of Schizochytrium powder, 7.5-12.4 parts of soy lecithin powder, 4-10 parts of maltitol, 8-12 parts of sodium butyrate, 8-15 parts of Chinese herbal medicine liquid, 0.2-0.8 parts of compound fermenting agent. Through steps such as raw material mixing, Chinese herbal medicine liquid fermentation, homogenization, puffing and spray drying in sequence, the feed quality control is carried out, so that the compound feed has a relatively high absorption rate and palatability, ensures the intake of the components of the Chinese herbal medicine fermentation liquid, significantly improves the survival rate and growth rate of freshwater fish, and has remarkable economic benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of fresh - water fish feed, and particularly relates to a compound fresh - water fish feed and a preparation method thereof. Background Art

[0002] Fresh - water fish refer to fish that can live in fresh water with a salinity of three per thousand. China is a major fishing country in the world, and the output of fresh - water fish ranks among the top in the world. It makes their muscle elasticity better and the taste delicious, such as grass carp, crucian carp, basa fish, etc.

[0003] Among them, basa fish is a special fresh - water fish in Southeast Asia. This fish is rich in protein components, has high nutritional value, delicate meat, delicious taste, fast growth rate, large individual size, high group yield, wide food habits, easy to raise, no inter - muscular spines, and is conducive to processing. It is deeply loved by farmers and consumers. The fry of the current year can grow to 500 - 800 grams after one - year feeding, and can grow to 1500 - 2000 grams in the second year. The largest individual can reach 15 kilograms. In recent years, with the continuous maturity of basa fish breeding technology, it has gradually come to people's tables. Common dishes include pan - fried basa fish, sweet - and - sour basa fish, pickled - cabbage basa fish, steamed basa fish, etc. The market demand for basa fish is increasing continuously, while the supply is far from enough, which has promoted its price to rise steadily. Therefore, breeding basa fish is one of the projects with good development prospects.

[0004] In recent years, with the expansion of market demand and the improvement of intensive farming level, basa fish in China has grown rapidly, with strong disease resistance, and the market sales situation is optimistic, being deeply loved by farmers. The basa fish industry has developed rapidly, especially in the middle and lower reaches of the Yangtze River with superior geographical conditions. However, under the condition of high - density farming, parasitic diseases of basa fish occur frequently, threatening the healthy development of the aquaculture industry. Although basa fish has strong disease resistance, due to the possible degradation of fish seedling quality or pollution of the breeding environment, there are also problems such as an increase in breeding diseases and the mismatch between feed and breeding requirements in the artificial breeding process. There are also many diseases in the basa fish breeding process. The most common ones are black - body disease, bacterial enteritis disease, etc. Neuro - necrosis virus, enteritis, and stress may all cause black - body of basa fish fry. This disease is mainly manifested as the body color of the fry turning black, swimming dispersedly by the pond side or in the net cage, with poor vitality and gradually dying. The neuro - necrosis virus is mainly vertically transmitted, so the fry hatched from the same female fish may all be virus - carrying. At the same time, there is obvious enteritis in the intestine, which is Aeromonas hydrophila. Basa fish enteritis is a common disease throughout the basa fish breeding process and is also the most important cause of death in the basa fish breeding process. If not handled well, it often leads to low breeding survival rate and slow growth, which is a very important factor affecting economic benefits. The occurrence of enteritis is related to the decline of the digestive function after the decline of the fry's body function. Summary of the Invention

[0005] In view of this, the present invention provides a compound feed for freshwater fish and a preparation method thereof to solve the above problems.

[0006] The technical solution of the present invention is realized as follows: A compound feed for freshwater fish: comprising the following raw materials in parts by weight: 39 - 44 parts of corn protein powder, 22 - 34 parts of cottonseed protein powder, 5.4 - 9.2 parts of black soldier fly larva powder, 11 - 23 parts of fish oil, 20 - 30 parts of Schizochytrium powder, 7.5 - 12.4 parts of soy lecithin powder, 4 - 10 parts of maltitol, 8 - 12 parts of sodium butyrate, 8 - 15 parts of Chinese herbal medicine liquid, 0.2 - 0.8 parts of compound fermenting agent, and the compound fermenting agent is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 1 - 4:3 - 5, and the viable bacteria content in the compound bacteria is 1×10 7 ~1×10 10 cuf / g.

[0007] Further, a compound feed for freshwater fish: comprising the following raw materials in parts by weight: 41 parts of corn protein powder, 28 parts of cottonseed protein powder, 7.2 parts of black soldier fly larva powder, 18 parts of fish oil, 25 parts of Schizochytrium powder, 9.5 parts of soy lecithin powder, 7 parts of maltitol, 10 parts of sodium butyrate, 12 parts of Chinese herbal medicine liquid, and 0.5 part of compound fermenting agent.

[0008] Further, the Chinese herbal medicine liquid is Coptis chinensis extract, Ampelopsis grossedentata extract, and Pteris vittata extract with a mass ratio of 3 - 11:5 - 21:1 - 6.

[0009] Further, the Coptis chinensis extract is obtained by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 40 - 60 - mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 85 - 95% under stirring to form a Coptis chinensis mixture, impregnating for 4 - 5 h, performing ultrasonic extraction at an ultrasonic frequency of 20 - 30 KHz and a temperature of 40 - 60 °C for 60 - 120 min, filtering the extract, and concentrating under reduced pressure to obtain the Coptis chinensis extract.

[0010] Further, the Ampelopsis grossedentata extract is an ethanol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder as a sample, soak the dry powder with ethanol, the mass - to - volume ratio of the dry powder to ethanol is 20 - 50:120 g / mL, let it stand at room temperature for 8 - 14 h, perform ultrasonic extraction for 1 - 3 h, perform vacuum filtration, extract continuously for 2 - 4 times, combine the filtrates, concentrate with a rotary evaporator at 40 - 50 °C, dry, and store at 3 - 6 °C for standby to obtain the Ampelopsis grossedentata extract.

[0011] Further, the extract of Pteris vittata is an aqueous extract. Weigh the dry powder of crushed Pteris vittata, soak it in distilled water for 20 - 40 min, first boil it with strong fire, then change to slow fire and decoct for 30 - 50 min. Filter the medicinal liquid while it is hot with gauze, repeat the extraction 1 - 3 times, adjust the pH value of the mixed liquid to 4.5 - 5.0, then let it stand for 24 h, and centrifuge to obtain the supernatant.

[0012] Further, a preparation method of a compound feed for freshwater fish comprises the following steps:

[0013] S1. Mixing: Mix the above-mentioned corn protein powder, cottonseed protein powder, black soldier fly larva powder, fish oil, Schizochytrium powder, soy phospholipid powder, maltitol, and sodium butyrate, stir evenly at 300 - 500 rpm, crush with an ultrafine grinder for 3 - 6 min, and then pass through a 100 - 200 - mesh sieve to obtain mixture I;

[0014] S2. Fermentation: Mix the compound fermenting agent and the Chinese herbal medicine liquid according to the above weight ratio, ferment at 23 - 34 °C for 10 - 20 days to obtain the Chinese herbal medicine fermented liquid for standby;

[0015] S3. Homogenization: Add the Chinese herbal medicine fermented liquid to mixture I, stir evenly, let it stand for 10 - 30 min, and then perform ultra - homogenization, with the number of homogenization times being 2 - 4 times;

[0016] S4. Extrusion: Pass in steam at 90 - 120 °C for modulation for 5 - 8 min, and make the material liquid enter an extrusion granulator to granulate at 100 - 150 °C;

[0017] S5. Spray drying: Spray - dry the above - mentioned feed pellets to make micro - capsule feed.

[0018] Further, the stirring time in S1 is 20 - 40 min.

[0019] Further, in S2, the homogenization pressure is 200 - 300 MPa, the homogenization temperature is 70 - 90 °C, and the homogenization time is 30 - 70 s.

[0020] Further, the spray - drying conditions in S5 are inlet air temperature 150 - 180 °C, air - conveying temperature 30 - 60 °C, outlet air temperature 80 - 100 °C, atomizer frequency 500 - 700 Hz, and the pressure difference between the inlet and outlet of the cyclone separator is 800 - 900 Pa.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] The formulated feed configured in the present invention can reduce the incidence of black body disease and enteritis in basa fish, achieving the effect of preventing bacterial enteritis and black body disease. During the experiment, the survival rate of basa fish was 95.1 - 98.4%, the incidence of black body disease was ≤0.6%, and the incidence of enteritis was ≤0.7%. It can effectively promote the healthy growth of basa fish, significantly improve the survival rate of fish and the quality of aquaculture, thereby reducing the aquaculture cost and alleviating the economic burden.

[0023] Among them, the raw materials of the formulated feed in the present invention are combined with protein source raw materials, fat source raw materials, sugar source raw materials, auxiliary materials and Chinese herbal medicine liquid, and are scientifically proportioned to synergistically play their better roles. The alkaloids contained in the Coptis chinensis extract and the glycoside compounds in the Pteris vittata extract have a strong adsorption effect on intestinal inflammatory substances and toxins, can optimize the intestinal microecological environment, and effectively prevent digestive tract diseases such as enteritis in basa fish. The myricetin in the Ampelopsis grossedentata extract combined with its feed raw materials can dilate blood vessels, maintain vascular tension, improve the blood circulation of fish, reduce the occurrence of black body disease. At the same time, instead of adding western medicine antibiotics, it defends through the fish's own immunity, improves the physique of the fish, and increases the survival rate.

[0024] The preparation method of the formulated feed in the present invention is carried out in sequence through steps such as raw material mixing, Chinese herbal medicine liquid fermentation, homogenization, puffing and spray drying, controlling the feed quality control, and preferably achieving a higher absorption rate and palatability in the formulated feed, ensuring the intake of the components of the Chinese medicine fermentation liquid, significantly increasing the survival rate and growth rate of freshwater fish, and having significant economic benefits. Detailed implementation mode

[0025] To better understand the technical content of the present invention, specific examples are provided below to further illustrate the present invention.

[0026] Unless otherwise specified, the experimental methods used in the examples of the present invention are all conventional methods.

[0027] Unless otherwise specified, the materials, reagents, etc. used in the examples of the present invention can all be obtained from commercial channels. Example 1

[0028] A formulated feed for freshwater fish: comprising the following raw materials in parts by weight: 39 parts of corn protein powder, 22 parts of cottonseed protein powder, 5.4 parts of black soldier fly larvae powder, 11 parts of fish oil, 20 parts of Schizochytrium powder, 7.5 parts of soy lecithin powder, 4 parts of maltitol, 8 parts of sodium butyrate, 8 parts of Chinese herbal medicine liquid, 0.2 part of compound fermenting agent. The compound fermenting agent is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 1:3, and the viable bacteria content in the compound bacteria is 1×10 7 cuf / g, and the Chinese herbal medicine liquid is Coptis chinensis extract, Ampelopsis grossedentata extract, and Pteris vittata extract with a mass ratio of 3:5:1.

[0029] The Coptis chinensis extract is prepared by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 40-mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 85% under stirring to form a Coptis chinensis mixture, impregnating for 4 h, performing ultrasonic extraction for 60 min at an ultrasonic frequency of 20 KHz and a temperature of 40 °C, filtering the extract, and concentrating under reduced pressure to obtain the Coptis chinensis extract;

[0030] The Ampelopsis grossedentata extract is the ethanol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder as the sample, soak the dry powder with ethanol, the mass-volume ratio of the dry powder to ethanol is 20:120 g / mL, let it stand at room temperature for 8 h, perform ultrasonic extraction for 1 h, filter by reduced pressure suction, extract continuously for 2 times, combine the filtrates, concentrate with a rotary evaporator at 40 °C, dry, and store at 3 °C for standby to obtain the Ampelopsis grossedentata extract;

[0031] The Pteris vittata extract is the water extract. Weigh the dried and pulverized Pteris vittata, soak it with distilled water for 20 min, first boil it with strong fire, then change to slow fire and decoct for 30 min, filter the medicinal liquid while it is hot with gauze, repeat the extraction once, adjust the pH value of the mixed liquid to 4.5 and then let it stand for 24 h, and centrifuge to separate to obtain the supernatant. Example 2

[0032] A compound feed for freshwater fish: It includes the following raw materials in parts by weight: 44 parts of corn protein powder, 34 parts of cottonseed protein powder, 9.2 parts of black soldier fly larvae powder, 23 parts of fish oil, 30 parts of Schizochytrium powder, 12.4 parts of soybean phospholipid powder, 10 parts of maltitol, 12 parts of sodium butyrate, 15 parts of Chinese herbal medicine liquid, 0.8 part of compound fermenter. The compound fermenter is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 4:5, and the viable bacteria content in the compound bacteria is 1×10 10 cuf / g. The Chinese herbal medicine liquid is a mixture of Coptis chinensis extract, Ampelopsis grossedentata extract, and Pteris vittata extract with a mass ratio of 11:21:6,

[0033] The Coptis chinensis extract is prepared by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 60-mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 95% under stirring to form a Coptis chinensis mixture, impregnating for 5 h, performing ultrasonic extraction for 120 min at an ultrasonic frequency of 30 KHz and a temperature of 60 °C, filtering the extract, and concentrating under reduced pressure to obtain the Coptis chinensis extract;

[0034] The Ampelopsis grossedentata extract is the ethanol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder as the sample, soak the dry powder with ethanol, the mass-volume ratio of the dry powder to ethanol is 50:120 g / mL, let it stand at room temperature for 14 h, perform ultrasonic extraction for 3 h, filter by reduced pressure suction, extract continuously for 4 times, combine the filtrates, concentrate with a rotary evaporator at 50 °C, dry, and store at 6 °C for standby to obtain the Ampelopsis grossedentata extract;

[0035] The Pteris vittata extract is an aqueous extract. Weigh the dried and crushed Pteris vittata, soak it in distilled water for 40 minutes, first boil it with strong fire, then change to slow fire and decoct for 50 minutes. Filter the medicinal liquid while it is hot with gauze, repeat the extraction 3 times, adjust the pH value of the mixed liquid to 5.0 and then let it stand for 24 hours, and centrifuge to obtain the supernatant. Example 3

[0036] A compound feed for freshwater fish: It includes the following raw materials in parts by weight: 41 parts of corn protein powder, 28 parts of cottonseed protein powder, 7.2 parts of black soldier fly larvae powder, 18 parts of fish oil, 25 parts of Schizochytrium powder, 9.5 parts of soy lecithin powder, 7 parts of maltitol, 10 parts of sodium butyrate, 12 parts of Chinese herbal medicine liquid, 0.5 part of compound fermenter. The compound fermenter is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 2:4, and the viable bacteria content in the compound bacteria is 1×10 8 cuf / g. The Chinese herbal medicine liquid is a mixture of Coptis chinensis extract, Ampelopsis grossedentata extract, and Pteris vittata extract with a mass ratio of 7:1:3.

[0037] The Coptis chinensis extract is prepared by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 50-mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 90% under stirring to form a Coptis chinensis mixed liquid, and impregnating for 4.5 hours. Then, perform ultrasonic extraction for 90 minutes at an ultrasonic frequency of 25 KHz and a temperature of 50 °C. Filter the extraction liquid and concentrate it under reduced pressure to obtain the Coptis chinensis extract.

[0038] The Ampelopsis grossedentata extract is an alcohol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder as a sample, soak the dry powder with ethanol, and the mass-volume ratio of the dry powder to ethanol is 30:120 g / mL. Let it stand at room temperature for 11 hours, perform ultrasonic extraction for 2 hours, perform vacuum filtration continuously for 3 times, combine the filtrates, concentrate with a rotary evaporator at 45 °C, dry, and store at 4 °C for standby to obtain the Ampelopsis grossedentata extract.

[0039] The Pteris vittata extract is an aqueous extract. Weigh the dried and crushed Pteris vittata, soak it in distilled water for 30 minutes, first boil it with strong fire, then change to slow fire and decoct for 40 minutes. Filter the medicinal liquid while it is hot with gauze, repeat the extraction 2 times, adjust the pH value of the mixed liquid to 4.5 and then let it stand for 24 hours, and centrifuge to obtain the supernatant.

[0040] The above Examples 1-3 adopt the following preparation method:

[0041] S1. Mixing: Mix the above-mentioned corn protein powder, cottonseed protein powder, black soldier fly larvae powder, fish oil, Schizochytrium powder, soy lecithin powder, maltitol, and sodium butyrate, stir at 400 rpm for 30 minutes until uniform, pulverize with a superfine pulverizer for 4 minutes, and pass through a 150-mesh sieve to obtain mixture I.

[0042] S2. Fermentation: Mix the compound fermenting agent and the Chinese herbal medicine liquid according to the above weight ratio, ferment at 29 °C for 15 days to obtain the Chinese herbal medicine fermented liquid for standby;

[0043] S3. Homogenization: Add the Chinese herbal medicine fermented liquid to the mixture I, stir evenly, let stand for 20 min, then perform ultra-homogenization. The homogenization pressure is 250 MPa, the homogenization temperature is 80 °C, the homogenization time is 50 s, and the number of homogenization times is 3 times;

[0044] S4. Extrusion puffing: Pass in steam at 110 °C and modulate for 7 min, and let the feed liquid enter the extrusion puffing granulator for granulation at 130 °C;

[0045] S5. Spray drying: Spray-dry the above feed pellets to make microcapsule feed. The spray-drying conditions are inlet air temperature 170 °C, air conveying temperature 50 °C, outlet air temperature 90 °C, atomizer frequency 600 Hz, and pressure difference between the inlet and outlet of the cyclone separator 850 Pa. Example 4

[0046] A compound feed for freshwater fish: It includes the following raw materials in parts by weight: 41 parts of corn protein powder, 28 parts of cottonseed protein powder, 7.2 parts of black soldier fly larvae powder, 18 parts of fish oil, 25 parts of Schizochytrium powder, 9.5 parts of soybean phospholipid powder, 7 parts of maltitol, 10 parts of sodium butyrate, 12 parts of Chinese herbal medicine liquid, 0.5 part of compound fermenting agent. The compound fermenting agent is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 2:4, and the viable bacteria content in the compound bacteria is 1×10 8 cuf / g. The Chinese herbal medicine liquid is the extraction liquid of Coptis chinensis, Ampelopsis grossedentata, and Pteris vittata with a mass ratio of 7:1:3.

[0047] The extraction liquid of Coptis chinensis is obtained by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 50-mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 90% under stirring to form a Coptis chinensis mixture, impregnating for 4.5 h, performing ultrasonic extraction at an ultrasonic frequency of 25 KHz and a temperature of 50 °C for 90 min, filtering the extraction liquid, and concentrating under reduced pressure to obtain the extraction liquid of Coptis chinensis;

[0048] The extraction liquid of Ampelopsis grossedentata is the ethanol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder as the sample, soak the dry powder with ethanol, the mass-volume ratio of the dry powder to ethanol is 30:120 g / mL, let stand at room temperature for 11 h, perform ultrasonic extraction for 2 h, filter under reduced pressure, extract continuously for 3 times, combine the filtrates, concentrate with a rotary evaporator at 45 °C, dry, and store at 4 °C for standby to obtain the extraction liquid of Ampelopsis grossedentata;

[0049] The Pteris vittata extract is an aqueous extract. Weigh the crushed dry product of Pteris vittata, soak it in distilled water for 30 minutes, first boil it with strong fire, then change to slow fire and decoct for 40 minutes. Filter the medicinal liquid while it is hot with gauze, repeat the extraction 2 times, adjust the pH value of the mixed liquid to 4.5 and then let it stand for 24 hours, and centrifuge to obtain the supernatant;

[0050] The compound feed is prepared by the following method:

[0051] S1. Mixing: Mix the above-mentioned corn protein powder, cottonseed protein powder, black soldier fly larva powder, fish oil, Schizochytrium powder, soybean phospholipid powder, maltitol, and sodium butyrate, stir at 300 rpm for 20 minutes until uniform, crush with an ultramicro pulverizer for 3 minutes, and pass through a 100-mesh sieve to obtain the mixed material I;

[0052] S2. Fermentation: Mix the compound fermenting agent and the Chinese herbal medicine liquid according to the above weight ratio, ferment at 23 °C for 10 days to obtain the Chinese herbal medicine fermented liquid for standby;

[0053] S3. Homogenization: Add the Chinese herbal medicine fermented liquid to the mixed material I and stir evenly, let it stand for 10 minutes, then perform ultra-homogenization. The homogenization pressure is 200 MPa, the homogenization temperature is 70 °C, the homogenization time is 30 s, and the number of homogenization times is 2;

[0054] S4. Extrusion: Pass in steam at 90 °C and modulate for 5 minutes, and let the material liquid enter the extrusion granulator to granulate at 100 °C;

[0055] S5. Spray drying: Spray dry the above feed pellets to make microcapsule feed. The spray drying conditions are inlet air temperature 150 °C, air conveying temperature 30 °C, outlet air temperature 80 °C, atomizer frequency 500 Hz, and air pressure difference between the inlet and outlet of the cyclone separator 800 Pa. Example 5

[0056] A compound feed for freshwater fish: It includes the following raw materials in parts by weight: 41 parts of corn protein powder, 28 parts of cottonseed protein powder, 7.2 parts of black soldier fly larva powder, 18 parts of fish oil, 25 parts of Schizochytrium powder, 9.5 parts of soybean phospholipid powder, 7 parts of maltitol, 10 parts of sodium butyrate, 12 parts of Chinese herbal medicine liquid, 0.5 part of compound fermenting agent. The compound fermenting agent is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 2:4, and the viable bacteria content in the compound bacteria is 1×10 8 cuf / g. The Chinese herbal medicine liquid is the Coptis chinensis extract, Ampelopsis grossedentata extract, and Pteris vittata extract with a mass ratio of 7:1:3,

[0057] The Coptis chinensis extract is prepared by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 50-mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 90% under stirring to form a Coptis chinensis mixture, impregnating for 4.5 h, performing ultrasonic extraction for 90 min at an ultrasonic frequency of 25 KHz and a temperature of 50 °C, filtering the extract, and concentrating under reduced pressure to obtain the Coptis chinensis extract;

[0058] The Ampelopsis grossedentata extract is the ethanol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder as a sample, soak the dry powder with ethanol, the mass-volume ratio of dry powder to ethanol is 30:120 g / mL, let it stand at room temperature for 11 h, perform ultrasonic extraction for 2 h, carry out vacuum filtration continuously for 3 times, combine the filtrates, concentrate with a rotary evaporator at 45 °C, dry, and store at 4 °C for later use to obtain the Ampelopsis grossedentata extract;

[0059] The Pteris vittata extract is an aqueous extract. Weigh the dried and pulverized Pteris vittata, soak it with distilled water for 30 min, first boil it with strong fire, then change to slow fire and decoct for 40 min, filter the medicinal liquid while it is hot with gauze, repeat the extraction 2 times, adjust the pH value of the mixed liquid to 4.5 and then let it stand for 24 h, and centrifuge to obtain the supernatant;

[0060] The compound feed is prepared by the following method:

[0061] S1. Mixing: Mix the above-mentioned corn protein powder, cottonseed protein powder, black soldier fly larva powder, fish oil, Schizochytrium powder, soybean phospholipid powder, maltitol, and sodium butyrate, stir at 500 rpm for 40 min until uniform, pulverize with an ultrafine pulverizer for 6 min, and pass through a 200-mesh sieve to obtain mixed material I;

[0062] S2. Fermentation: Mix the compound fermenting agent and the Chinese herbal medicine liquid according to the above weight ratio, ferment at 34 °C for 20 days to obtain the Chinese herbal medicine fermented liquid for later use;

[0063] S3. Homogenization: Add the Chinese herbal medicine fermented liquid to mixed material I and stir evenly, let it stand for 30 min, then perform ultra-homogenization, the homogenization pressure is 300 MPa, the homogenization temperature is 90 °C, the homogenization time is 70 s, and the number of homogenization times is 4 times;

[0064] S4. Extrusion: Pass in steam at 120 °C for modulation for 8 min, and make the feed liquid enter an extrusion granulator for granulation at 150 °C;

[0065] S5. Spray drying: Spray dry the above-mentioned feed pellets to make microcapsule feed, and the spray drying conditions are inlet air temperature 180 °C, air delivery temperature 60 °C, outlet air temperature 100 °C, atomizer frequency 700 Hz, and air pressure difference between the inlet and outlet of the cyclone separator 900 Pa. Control Example 1

[0066] The difference between this comparative example and Example 3 lies in a compound feed for freshwater fish, which comprises the following raw materials in parts by weight: 30 parts of corn protein powder, 20 parts of cottonseed protein powder, 13 parts of black soldier fly larvae powder, 10 parts of fish oil, 38 parts of Schizochytrium powder, 22 parts of soy lecithin powder, 15 parts of maltitol, 15 parts of sodium butyrate, 5 parts of Chinese herbal medicine liquid, and 0.1 part of compound fermenting agent; the compound fermenting agent is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 2:4, and the viable bacteria content in the compound bacteria is 1×10 8 cuf / g, and the Chinese herbal medicine liquid is an extract of Coptis chinensis, Ampelopsis grossedentata, and Pteris vittata with a mass ratio of 7:1:3.

[0067] The Coptis chinensis extract is prepared by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 50-mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 90% under stirring to form a Coptis chinensis mixture, impregnating for 4.5 h, performing ultrasonic extraction at an ultrasonic frequency of 25 KHz and a temperature of 50 °C for 90 min, filtering the extract, and concentrating under reduced pressure to obtain the Coptis chinensis extract.

[0068] The Ampelopsis grossedentata extract is an ethanol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder as a sample, soak the dry powder with ethanol, the mass-volume ratio of the dry powder to ethanol is 30:120 g / mL, let it stand at room temperature for 11 h, perform ultrasonic extraction for 2 h, perform vacuum filtration continuously for 3 times, combine the filtrates, concentrate with a rotary evaporator at 45 °C, dry, and store at 4 °C for standby to obtain the Ampelopsis grossedentata extract.

[0069] The Pteris vittata extract is a water extract. Weigh the dried and pulverized Pteris vittata, soak it with distilled water for 30 min, first boil it with strong fire, then change to slow fire and decoct for 40 min, filter the medicinal liquid while it is hot with a gauze, repeat the extraction 2 times, adjust the pH value of the mixed liquid to 4.5 and let it stand for 24 h, and centrifuge to obtain the supernatant.

[0070] The following preparation method is adopted:

[0071] S1. Mixing: Mix the above-mentioned corn protein powder, cottonseed protein powder, black soldier fly larvae powder, fish oil, Schizochytrium powder, soy lecithin powder, maltitol, and sodium butyrate, stir at 400 rpm for 30 min until uniform, pulverize with a superfine pulverizer for 4 min, and pass through a 150-mesh sieve to obtain mixed material I.

[0072] S2. Fermentation: Mix the compound fermenting agent and the Chinese herbal medicine liquid according to the above weight ratio, ferment at 29 °C for 15 days to obtain the Chinese herbal medicine fermentation liquid for standby.

[0073] S3. Homogenization: Add the Chinese herbal medicine fermentation liquid to mixed material I, stir evenly, let it stand for 20 min, then perform superhomogenization, the homogenization pressure is 250 MPa, the homogenization temperature is 80 °C, the homogenization time is 50 s, and the number of homogenization times is 3 times.

[0074] S4. Extrusion: Pass in steam at 110°C and modulate for 7 min, and make the feed liquid enter the extrusion granulator to granulate under the condition of 130°C;

[0075] S5. Spray drying: Spray dry the above feed pellets to make microcapsule feed. The spray drying conditions are inlet air temperature 170°C, air conveying temperature 50°C, outlet air temperature 90°C, atomizer frequency 600 Hz, and air pressure difference between the inlet and outlet of the cyclone separator 850 Pa. Comparative Example 2

[0076] The difference between this comparative example and Example 3 is that the Chinese herbal medicine liquid is not added to the compound feed for freshwater fish. Specifically, a compound feed for freshwater fish includes the following raw materials in parts by weight: 41 parts of corn protein powder, 28 parts of cottonseed protein powder, 7.2 parts of black soldier fly larva powder, 18 parts of fish oil, 25 parts of Schizochytrium powder, 9.5 parts of soy lecithin powder, 7 parts of maltitol, 10 parts of sodium butyrate, and 0.5 part of compound fermenting agent. The compound fermenting agent is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 2:4, and the viable bacteria content in the compound bacteria is 1×10 8 cuf / g;

[0077] The following preparation method is adopted:

[0078] S1. Mixing: Mix the above corn protein powder, cottonseed protein powder, black soldier fly larva powder, fish oil, Schizochytrium powder, soy lecithin powder, maltitol, and sodium butyrate, stir at 400 rpm for 30 min until uniform, crush with an ultrafine grinder for 4 min, and pass through a 150-mesh sieve to obtain mixed material I;

[0079] S2. Homogenization: Perform super homogenization on mixed material I. The homogenization pressure is 250 MPa, the homogenization temperature is 80°C, the homogenization time is 50 s, and the number of homogenization times is 3 times;

[0080] S3. Extrusion: Pass in steam at 110°C and modulate for 7 min, and make the feed liquid enter the extrusion granulator to granulate under the condition of 130°C;

[0081] S4. Spray drying: Spray dry the above feed pellets to make microcapsule feed. The spray drying conditions are inlet air temperature 170°C, air conveying temperature 50°C, outlet air temperature 90°C, atomizer frequency 600 Hz, and air pressure difference between the inlet and outlet of the cyclone separator 850 Pa. Comparative Example 3

[0082] The difference between this comparative example and Example 3 is that in the raw materials of the freshwater fish compound feed, the Chinese herbal medicine liquid is not fermented by a compound fermenting agent. Specifically, it is a kind of freshwater fish compound feed, including the following raw materials in parts by weight: 41 parts of corn protein powder, 28 parts of cottonseed protein powder, 7.2 parts of black soldier fly larva powder, 18 parts of fish oil, 25 parts of Schizochytrium powder, 9.5 parts of soybean phospholipid powder, 7 parts of maltitol, 10 parts of sodium butyrate, and 12 parts of Chinese herbal medicine liquid. The Chinese herbal medicine liquid is the extraction liquid of Coptis chinensis, Ampelopsis grossedentata, and Pteris vittata with a mass ratio of 7:1:3.

[0083] The following preparation method is adopted:

[0084] S1. Mixing: Mix the above-mentioned corn protein powder, cottonseed protein powder, black soldier fly larva powder, fish oil, Schizochytrium powder, soybean phospholipid powder, maltitol, and sodium butyrate, stir at 400 rpm for 30 min until uniform, crush with a superfine pulverizer for 4 min, and pass through a 150-mesh sieve to obtain mixed material I;

[0085] S2. Homogenization: Add the Chinese herbal medicine liquid to mixed material I, stir evenly, let it stand for 20 min, and then perform ultra-homogenization. The homogenization pressure is 250 MPa, the homogenization temperature is 80 °C, the homogenization time is 50 s, and the number of homogenization times is 3 times;

[0086] S3. Extrusion: Pass in steam at 110 °C and modulate for 7 min, and let the feed liquid enter the extrusion granulator at 130 °C for granulation;

[0087] S4. Spray drying: Spray dry the above-mentioned feed pellets to make microcapsule feed. The spray drying conditions are inlet air temperature of 170 °C, air delivery temperature of 50 °C, outlet air temperature of 90 °C, atomizer frequency of 600 Hz, and air pressure difference between the inlet and outlet of the cyclone separator of 850 Pa.

[0088] Comparison of aquaculture experiment effects:

[0089] The aquaculture experiment was carried out at the Qizi Bay Aquaculture Farm in Changjiang, Hainan from March 20, 2022 to September 20, 2022. 18,000 healthy and uniformly sized Pangasius bocourti were selected and transferred into 9 experimental aquaculture ponds respectively. The freshwater fish compound feeds prepared in the above Examples 1-5 and Comparative Examples 1-3 and the received compound feeds (purchased from Zhuhai Shihai Feed) were used to feed the Pangasius bocourti. The same batch of Pangasius bocourti was put into the aquaculture ponds, with 2,000 tails in each pond. Each kind of feed was set with 3 replicates. After 6 months of aquaculture, the survival rate, incidence rate of black body disease, cure rate, incidence rate and cure rate of bacterial enteritis disease of Pangasius bocourti during the growth process were measured, and the test results were calculated. The results are shown in Table 1:

[0090] Survival rate % Incidence rate of black body disease % Incidence rate of enteritis disease % Example 1 96.7 0.6 0.7 Example 2 97.2 0.4 0.6 Example 3 98.4 0.2 0.4 Example 4 95.8 0.5 0.5 Example 5 95.1 0.3 0.6 Comparative Example 1 90.3 1.9 1.9 Comparative Example 2 89.3 2.5 2.9 Comparative Example 3 91.0 1.4 2.3 Commercially available 77.3 5.4 6.8

[0091] As can be seen from the above results, the formulated feed of the present invention can reduce the incidence of black body disease and enteritis in basa fish, achieving the effect of preventing bacterial enteritis and black body disease. Compared with the commercially available formulated feed, it can effectively promote the healthy growth of basa fish, significantly improve the survival rate of fish and the quality of aquaculture, thereby reducing the aquaculture cost and alleviating the economic burden;

[0092] From the results in Table 1 and the comparative tests, when comparing the example group with Comparative Example 1, the scientific ratio of each formulated feed raw material plays a better role synergistically. The survival rate of the example group is 95.1 - 98.4%, the incidence of black body disease is ≤0.6%, and the incidence of enteritis is ≤0.7%.

[0093] When comparing the example group with Comparative Example 2, Chinese herbal medicine liquid is added to the formulated feed. Among them, the extracted liquid of Coptis chinensis, Ampelopsis grossedentata, and Pteris vittata are screened out. After scientific ratio and selection of the better ratio, they play a role synergistically. The alkaloids contained in the extracted liquid of Coptis chinensis and the glycoside compounds in the extracted liquid of Pteris vittata have a strong adsorption effect on intestinal inflammatory substances and toxins. Combining with protein source raw materials (corn gluten meal, cottonseed protein meal, black soldier fly larvae powder) can optimize the intestinal microecological environment and effectively prevent digestive tract diseases such as enteritis in basa fish. The myricetin in the extracted liquid of Ampelopsis grossedentata combines with its feed raw materials to dilate blood vessels, maintain vascular tension, improve the blood circulation of fish, and reduce the occurrence of black body disease;

[0094] When comparing the example group with Comparative Example 3, the Chinese herbal medicine liquid is fermented with compound bacteria to produce an active traditional Chinese medicine fermentation liquid beneficial to fish, generating small molecule probiotic groups. The active ingredients in the Chinese herbal medicine liquid after fermentation can be absorbed by the fish intestine in multiples and easily, enhancing the fish immunity and clearing harmful bacteria in the intestine.

[0095] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A compound feed for freshwater fish, characterized in that: It includes the following raw materials in parts by weight: 39 - 44 parts of corn protein powder, 22 - 34 parts of cottonseed protein powder, 5.4 - 9.2 parts of black soldier fly larvae powder, 11 - 23 parts of fish oil, 20 - 30 parts of Schizochytrium powder, 7.5 - 12.4 parts of soy lecithin powder, 4 - 10 parts of maltitol by mass, 8 - 12 parts of sodium butyrate, 8 - 15 parts of Chinese herbal medicine liquid, 0.2 - 0.8 parts of compound fermenting agent. The Chinese herbal medicine liquid is the extraction liquid of Coptis chinensis, Ampelopsis grossedentata and Pteris vittata with a mass ratio of 3 - 11:5 - 21:1 - 6. The compound fermenting agent is Lactobacillus pentosus and Staphylococcus xylosus with a weight ratio of 1 - 4:3 - 5, and the viable bacteria content in the compound bacteria is 1×10 7 ~1×10 10 cuf / g; The preparation method of the compound feed for freshwater fish includes the following steps: S1. Mixing: Mix the above-mentioned corn protein powder, cottonseed protein powder, black soldier fly larvae powder, fish oil, Schizochytrium powder, soy lecithin powder, maltitol, and sodium butyrate, stir evenly at 300 - 500 rpm, crush with an ultrafine pulverizer for 3 - 6 min, and pass through a 100 - 200 mesh sieve to obtain mixed material I; S2. Fermentation: Mix the compound fermenting agent and the Chinese herbal medicine liquid according to the above weight ratio, ferment at 23 - 34 °C for 10 - 20 days to obtain the Chinese herbal medicine fermented liquid for standby; S3. Homogenization: Add the Chinese herbal medicine fermented liquid to mixed material I, stir evenly, let it stand for 10 - 30 min, and then perform ultra - homogenization, with the number of homogenization times being 2 - 4 times; S4. Extrusion: Pass in steam at 90 - 120 °C for modulation for 5 - 8 min, and let the material liquid enter the extrusion granulator for granulation under the condition of 100 - 150 °C; S5. Spray drying: Spray - dry the feed pellets to make micro - capsule feed.

2. A compound feed for freshwater fish as described in claim 1, characterized in that: It includes the following raw materials in parts by weight: 41 parts of corn protein powder, 28 parts of cottonseed protein powder, 7.2 parts of black soldier fly larvae powder, 18 parts of fish oil, 25 parts of Schizochytrium powder, 9.5 parts of soy lecithin powder, 7 parts of maltitol, 10 parts of sodium butyrate, 12 parts of Chinese herbal medicine liquid, and 0.5 part of compound fermenting agent.

3. A compound feed for freshwater fish as described in claim 1, characterized in that: The Coptis chinensis extract is obtained by putting dried Coptis chinensis into a pulverizer for pulverization, passing through a 40 - 60 mesh sieve, putting it into a stirrer, adding an ethanol solution with a volume concentration of 85 - 95% under stirring to form a Coptis chinensis mixed solution, impregnating for 4 - 5 h, performing ultrasonic extraction at an ultrasonic frequency of 20 - 30 KHz and a temperature of 40 - 60 °C for 60 - 120 min, filtering the extract, and performing vacuum concentration to obtain the Coptis chinensis extract.

4. A compound feed for freshwater fish as described in claim 1, characterized in that: The Ampelopsis grossedentata extract is an ethanol extract of Ampelopsis grossedentata. Take Ampelopsis grossedentata powder and soak it with ethanol, with the mass - to - volume ratio of the powder to ethanol being 20 - 50:120 g / mL, let it stand at room temperature for 8 - 14 h, perform ultrasonic extraction for 1 - 3 h, perform vacuum filtration, extract continuously for 2 - 4 times, combine the filtrates, concentrate with a rotary evaporator at 40 - 50 °C, and store it at 3 - 6 °C for standby after drying to obtain the Ampelopsis grossedentata extract.

5. A compound feed for freshwater fish as described in claim 1, characterized in that: The Pteris vittata extract is a water extract. Weigh the dried and pulverized Pteris vittata, soak it with distilled water for 20 - 40 min, first boil it with strong fire, then change to slow fire and decoct for 30 - 50 min, filter the medicinal liquid while it is hot with gauze, repeat the extraction for 1 - 3 times, adjust the pH value of the mixed liquid to 4.5 - 5.0, let it stand for 24 h, and centrifuge to obtain the supernatant.

6. A compound feed for freshwater fish as described in claim 1, characterized in that: The stirring time in S1 of the preparation method is 20 - 40 min.

7. A compound feed for freshwater fish as described in claim 1, It is characterized in that: In step S3 of the preparation method, the homogenization pressure is 200 - 300 MPa, the homogenization temperature is 70 - 90 °C, and the homogenization time is 30 - 70 s.

8. A compound feed for freshwater fish according to claim 1, It is characterized in that: In step S5 of the preparation method, the spray drying conditions are inlet air temperature 150 - 180 °C, pneumatic conveying temperature 30 - 60 °C, outlet air temperature 80 - 100 °C, atomizer frequency 500 - 700 Hz, and the pressure difference between the inlet and outlet of the cyclone separator 800 - 900 Pa.