阅读说明：本技术 一种添加浮萍干粉的促生长的罗非鱼饲料及其制备方法 (Growth-promoting tilapia feed added with duckweed dry powder and preparation method thereof ) 是由 韩冰莹 张家明 陈婷 于博涵 付莉莉 谭德冠 孙雪飘 于 2021-01-25 设计创作，主要内容包括：本发明提供一种添加浮萍干粉的促生长的罗非鱼饲料其制备方法,该饲料包括：35-38份浮萍干粉、4-7份鱼粉、12-13份玉米蛋白粉、0.2-0.6份半枝莲提取物、8-10份次粉、6-10份一级大豆粕、6-10份一级棉籽粕、4-6份木薯、4-8份花生仁粕、3-4份啤酒糟、11-13份麦芽根、3-5份大豆油、0.8-1.2份食盐和2.5-3.5份预混料；本发明制得的罗非鱼饲料可显著提高罗非鱼的质量增加率、肥满度、脏体比以及特定生长率,促进罗非鱼鱼苗的生长发育,体色更加鲜艳,并且肝脏稳定发育,降低脂肪肝的风险,实现浮萍在罗非鱼饲料中的更高效利用。(The invention provides a tilapia feed added with duckweed dry powder and capable of promoting growth and a preparation method thereof, wherein the feed comprises the following components: 35-38 parts of duckweed dry powder, 4-7 parts of fish meal, 12-13 parts of corn protein powder, 0.2-0.6 part of sculellaria barbata extract, 8-10 parts of wheat middling, 6-10 parts of primary soybean meal, 6-10 parts of primary cottonseed meal, 4-6 parts of cassava, 4-8 parts of peanut kernel meal, 3-4 parts of brewer's grain, 11-13 parts of malt root, 3-5 parts of soybean oil, 0.8-1.2 parts of salt and 2.5-3.5 parts of premix; the tilapia feed prepared by the invention can obviously improve the quality increase rate, the fullness, the viscera-body ratio and the specific growth rate of tilapia, promote the growth and development of tilapia fries, make the body color more bright, stabilize the liver, reduce the risk of fatty liver and realize the more efficient utilization of duckweed in the tilapia feed.)

1. A tilapia feed added with duckweed dry powder and capable of promoting growth is characterized in that: the composite material comprises the following raw materials in parts by weight: 35-38 parts of duckweed dry powder, 4-7 parts of fish meal, 12-13 parts of corn protein powder, 0.2-0.6 part of sculellaria barbata extract, 8-10 parts of wheat middling, 6-10 parts of primary soybean meal, 6-10 parts of primary cottonseed meal, 4-6 parts of cassava, 4-8 parts of peanut kernel meal, 3-4 parts of brewer's grain, 11-13 parts of malt root, 3-5 parts of soybean oil, 0.8-1.2 parts of salt and 2.5-3.5 parts of premix.

2. The feed for tilapia growth promotion added with duckweed dry powder according to claim 1, wherein: the weight ratio of the duckweed dry powder to the fish meal to the corn protein powder is as follows: 36.5:5.5:12.5.

3. The feed for tilapia growth promotion added with duckweed dry powder according to claim 2, wherein: the duckweed dry powder is obtained by performing steam explosion treatment under the pressure of 1.0-1.4 Mpa and standing and degrading cellulase liquid at 48-53 ℃ for more than 24 hours.

4. The feed for tilapia growth promotion added with duckweed dry powder of claim 3, wherein: the sculellaria barbata extract is obtained by reflux extraction of sculellaria barbata at 80-85 ℃ by taking an ethanol solution with the mass concentration of 85% as a solvent.

5. A preparation method of the duckweed dry powder added growth-promoting tilapia feed as claimed in any one of claims 1 to 4, characterized by comprising the following steps: the method comprises the following steps:

weighing duckweed dry powder, fish meal, corn protein powder, wheat middling, primary soybean meal, primary cottonseed meal, cassava, peanut kernel meal, brewer's grains and malt roots according to formula components, mixing, carrying out superfine grinding until 95% of the mixture reaches 90-100 meshes, adding a sculellaria barbata extract, soybean oil, salt and a premix into a mixer, mixing and stirring uniformly, preparing a granulated feed with the diameter of about 2.8-3.3 mm by using a granulator, and drying to obtain the growth-promoting tilapia feed, wherein the tilapia feed is preserved in a dark place at normal temperature.

6. The method of claim 5, wherein the method comprises the steps of: the preparation method of the duckweed dry powder comprises the following steps:

(1) fishing out fresh duckweed, washing to remove impurities, filtering to remove water, and drying in a dryer at 55-65 ℃;

(2) performing steam explosion treatment on the dried duckweed at the pressure of 1.0-1.4 Mpa for 80-100 s, screening the duckweed through a 60-mesh screen, and drying to obtain pretreated duckweed powder;

(3) adding 0.35-0.45 ml of separated and purified cellulase liquid into each gram of duckweed powder, uniformly mixing, standing at 48-53 ℃ for enzymolysis for 26-30 h, and drying to obtain duckweed dry powder.

7. The method of claim 5, wherein the method comprises the steps of: the preparation method of the sculellaria barbata extract comprises the following steps: cleaning fresh barbat skullcap, crushing by using an ultrafine crusher, adding an ethanol solution with the mass concentration of 85% and the volume of 8-10 times of that of the crushed barbat skullcap, performing reflux extraction at 80-85 ℃ for 3-5 hours, repeating the extraction for 1-2 times, combining filtrates, concentrating and drying to obtain the barbat skullcap extract.

8. The method of claim 5, wherein the method comprises the steps of: the conditioning temperature during granulation is 90-95 ℃, and the drying of the granulated feed is 70-80 ℃ hot air drying.

Technical Field

The invention relates to the technical field of feeds, in particular to a growth-promoting tilapia feed added with duckweed dry powder and a preparation method thereof.

Background

Tilapia belongs to Tilapia of Tilapaceae, and is native to Africa, namely Fushou fish, Africa crucian carp, Nanyang crucian carp and the like. The feed has the advantages of high growth speed, high feeding quality, strong disease resistance and strong adaptability, is suitable for high-density intensive culture in fresh water or brackish water ponds and net cages, has delicious and tender meat quality and less thorn, and is deeply loved by consumers. With the development of tilapia aquaculture industry, the demand of tilapia feed is continuously increased, the most main protein source in aquatic animal feed is fish meal, but the yield of the feed is reduced year by year, and excessive use of the feed can cause phosphorus pollution, so that the feed is suitable for the aquaculture of tilapia. The protein source of the feed is increasingly tense, so that people pay more attention to fully improving the utilization rate of aquatic animals to various protein sources, and therefore, the finding of a protein with more guaranteed safety as a fish meal substitute is of particular significance.

The protein content of the duckweed serving as a livestock and poultry protein feed resource can be compared favorably with that of soybean, and the amino acid composition is synergistic, so that the duckweed is a very promising plant protein resource, but the duckweed serving as a protein source is compounded and applied to the process of aquatic animal seedling culture, the culture effect of the fry is greatly reduced compared with that of the duckweed, particularly for tilapia teleosts, the liver body ratio needs to be controlled to be 1-2%, and if excessive duckweed is adopted to replace a fish meal protein source, the phenomenon of liver swelling due to overweight fat metabolism of liver and pancreas of the fry is easy to occur, so the use amount of the duckweed in the tilapia teleosts is greatly limited, the duckweed feed is not beneficial to wider application in the aquaculture industry, and the shortage of the protein source in the aquatic animal feed is made up.

Disclosure of Invention

Therefore, the invention provides a tilapia feed added with duckweed dry powder and capable of promoting growth and a preparation method thereof.

The technical scheme of the invention is realized as follows:

the invention provides a tilapia feed added with duckweed dry powder and capable of promoting growth, which comprises the following raw materials in parts by weight: 35-38 parts of duckweed dry powder, 4-7 parts of fish meal, 12-13 parts of corn protein powder, 0.2-0.6 part of sculellaria barbata extract, 8-10 parts of wheat middling, 6-10 parts of primary soybean meal, 6-10 parts of primary cottonseed meal, 4-6 parts of cassava, 4-8 parts of peanut kernel meal, 3-4 parts of brewer's grain, 11-13 parts of malt root, 3-5 parts of soybean oil, 0.8-1.2 parts of salt and 2.5-3.5 parts of premix. The tilapia feed prepared by the invention can obviously improve the quality increase rate, the fullness, the viscera-body ratio and the specific growth rate of tilapia, promote the growth and development of tilapia fries, make the body color more bright, stabilize the liver, reduce the risk of fatty liver and realize the more efficient utilization of duckweed in the tilapia feed.

More preferably, the weight ratio of the duckweed dry powder to the fish meal to the corn protein powder is as follows: 36.5:5.5:12.5.

More preferably, the fish meal is cp 64.5% fish meal, and the corn gluten meal is cp 60% corn gluten meal.

More preferably, the duckweed dry powder is obtained by standing and degrading cellulase liquid for more than 24 hours at 48-53 ℃ after steam explosion treatment under the pressure of 1.0-1.4 Mpa.

More preferably, the sculellaria barbata extract is obtained by reflux extraction of sculellaria barbata at 80-85 ℃ by taking an ethanol solution with the mass concentration of 85% as a solvent.

A preparation method of a growth-promoting tilapia feed added with duckweed dry powder comprises the following steps:

weighing duckweed dry powder, fish meal, corn protein powder, wheat middling, primary soybean meal, primary cottonseed meal, cassava, peanut kernel meal, brewer's grains and malt roots according to formula components, mixing, carrying out superfine grinding until 95% of the mixture reaches 90-100 meshes, adding a sculellaria barbata extract, soybean oil, salt and a premix into a mixer, mixing and stirring uniformly, preparing a granulated feed with the diameter of about 2.8-3.3 mm by using a granulator, and drying to obtain the growth-promoting tilapia feed, wherein the tilapia feed is preserved in a dark place at normal temperature.

Further, the preparation method of the duckweed dry powder comprises the following steps:

(1) fishing out fresh duckweed, washing to remove impurities, filtering to remove water, and drying in a dryer at 55-65 ℃;

(2) performing steam explosion treatment on the dried duckweed at the pressure of 1.0-1.4 Mpa for 80-100 s, screening the duckweed through a 60-mesh screen, and drying to obtain pretreated duckweed powder;

(3) adding 0.35-0.45 ml of separated and purified cellulase liquid into each gram of duckweed powder, uniformly mixing, standing at 48-53 ℃ for enzymolysis for 26-30 h, and drying to obtain duckweed dry powder.

Further, the preparation method of the sculellaria barbata extract comprises the following specific steps: cleaning fresh barbat skullcap, crushing by using an ultrafine crusher, adding an ethanol solution with the mass concentration of 85% and the volume of 8-10 times of that of the crushed barbat skullcap, performing reflux extraction at 80-85 ℃ for 3-5 hours, repeating the extraction for 1-2 times, combining filtrates, concentrating and drying to obtain the barbat skullcap extract.

Further, the conditioning temperature is 90-95 ℃ during granulation, and the drying of the granulated feed is 70-80 ℃ hot air drying.

Compared with the prior art, the invention has the beneficial effects that: according to the tilapia feed provided by the invention, duckweed dry powder, fish meal and corn protein powder are compounded in a certain proportion, and auxiliary materials such as soybean meal, cottonseed meal and peanut kernel meal are matched, so that the tilapia feed has more comprehensive nutrition, the mass increase rate, the fullness, the dirty body ratio and the specific growth rate of tilapia can be obviously improved, the growth and development of tilapia fries are promoted, and the body color of the fries is more bright; meanwhile, the scutellaria barbata extract with a certain proportion is added and combined with the duckweed dry powder, so that the activity of digestive enzymes in stomach, intestinal tract and liver and pancreas of tilapia can be better regulated and controlled, the secretion and activity of the digestive enzymes are promoted, the utilization rate of natural pigments of proteins, vitamins and flavonoids in the duckweed dry powder is improved, the fat metabolism rate in liver of tilapia under high-dosage duckweed is effectively ensured, the liver swelling phenomenon of a fish body is avoided, the stable development of the liver is promoted, the risk of fatty liver is reduced, the fish meal is better replaced by effectively increasing the dosage of the duckweed dry powder, the occupation ratio of the feed can reach more than 30%, and the nutrition and stability of the obtained tilapia feed meet the national standard.

In addition, the invention further adopts the combined action of physical steam explosion and deep degradation to more thoroughly degrade the duckweed, so that the crude cellulose content in the duckweed is reduced, and simultaneously, the nutrient components in the duckweed are ensured to be better combined with the sculellaria barbata extract, thereby greatly promoting the digestion and absorption of the fry, improving the digestibility of the fry on feed and fully improving the growth rate of the tilapia fry.

Detailed Description

In order to better understand the technical content of the invention, specific examples are provided below to further illustrate the invention.

The experimental methods used in the examples of the present invention are all conventional methods unless otherwise specified.

The materials, reagents and the like used in the examples of the present invention can be obtained commercially without specific description.

Examples 1 to 3

The growth-promoting tilapia feed added with the duckweed dry powder comprises the following raw material formulas in parts by weight:

wherein, the duckweed dry powder is dried at 55 ℃, is subjected to steam explosion treatment for 80s under the pressure of 1.0Mpa, is sieved, and is prepared by mixing the following components in a material-liquid ratio of 1: adding 0.35g/ml cellulase solution, standing at 48 deg.C for degradation for 26h, and drying to obtain duckweed dry powder; the cellulase liquid is produced from Aspergillus niger which is purchased from China general microbiological culture Collection center with the number of 3.3928.

The preparation method of the tilapia feed comprises the following steps:

weighing duckweed dry powder, fish meal, corn protein powder, wheat middling, primary soybean meal, primary cottonseed meal, cassava, peanut kernel meal, brewer's grains and malt roots according to formula components, mixing, carrying out superfine grinding until 95% of the mixture reaches 90 meshes, adding a sculellaria barbata extract, soybean oil, salt and a premix into a mixer, mixing and stirring uniformly, preparing a granulated feed with the diameter of about 2.8mm by adopting a granulator, carrying out hot air drying at the temperature of 70 ℃ when granulating, and obtaining the growth-promoting tilapia feed, wherein the dried duckweed feed is preserved in a dark place at normal temperature.

Example 4

A growth-promoting tilapia feed comprises the following raw materials in parts by weight: 36.5 parts of duckweed dry powder, 5.5 parts of fish meal cp 64.5%, 12.5 parts of corn protein powder cp 60%, 0.5 part of sculellaria barbata extract, 9 parts of wheat middling, 8 parts of primary soybean meal, 8 parts of primary cottonseed meal, 5 parts of cassava, 6 parts of peanut kernel meal, 3.5 parts of brewer's grains, 12 parts of malt roots, 4 parts of soybean oil, 1 part of salt and 3 parts of premix;

wherein, the duckweed dry powder is obtained by performing steam explosion treatment under the pressure of 1.4Mpa and standing and degrading cellulase liquid at 53 ℃ for 30 h; the cellulase liquid is produced by Aspergillus niger, which is purchased from China general microbiological culture Collection center, number 3.3928. The method specifically comprises the following steps:

(1) fishing out fresh duckweed, washing to remove impurities, filtering to remove water, and drying in a dryer at 65 ℃;

(2) performing 100s steam explosion treatment on the dried duckweed under the pressure of 1.4Mpa, sieving with a 60-mesh sieve, and drying to obtain pretreated duckweed powder;

(3) adding 0.45ml of separated and purified cellulase liquid into each gram of duckweed powder, uniformly mixing, standing at 53 ℃ for enzymolysis for 30 hours, and drying to obtain duckweed dry powder;

the sculellaria barbata extract is prepared by reflux-extracting sculellaria barbata with 85% ethanol solution as a solvent at 83 ℃, and specifically comprises the following steps: cleaning fresh herba Scutellariae Barbatae, pulverizing with a micronizer, adding 9 times volume of 85% ethanol solution, reflux-extracting at 83 deg.C for 4 hr, repeating for 2 times, mixing filtrates, concentrating, and drying to obtain herba Scutellariae Barbatae extract.

The tilapia feed is prepared according to the following preparation method, and comprises the following steps:

weighing duckweed dry powder, fish meal, corn protein powder, wheat middling, primary soybean meal, primary cottonseed meal, cassava, peanut kernel meal, brewer's grains and malt roots according to formula components, mixing, carrying out superfine grinding until 95% of the mixture reaches 100 meshes, adding a sculellaria barbata extract, soybean oil, salt and a premix into a mixer, mixing and stirring uniformly, preparing a granulated feed with the diameter of about 3.3mm by adopting a granulator, carrying out hot air drying at the temperature of 70 ℃ when granulating, and obtaining the growth-promoting tilapia feed, wherein the dried duckweed feed is preserved in a dark place at normal temperature.

Example 5

This example differs from example 4 in that: in the tilapia feed formula, duckweed dry powder is not pretreated. Namely, fresh duckweed is fished, impurities are washed away, water is filtered out, the duckweed is dried in a dryer at 65 ℃, and then the duckweed dry powder is obtained by mechanical crushing of a crusher.

Comparative example 1

This comparative example differs from example 4 in that: in the formula of the tilapia feed, the sculellaria barbata extract is not added.

Comparative example 2

This comparative example differs from example 4 in that: in the formula of the tilapia feed, the weight ratio of the duckweed dry powder to the fish meal to the corn protein powder is as follows: 36.5:2.5:11.5.

According to the tilapia feed prepared by the tilapia feed formulas and the preparation methods of the embodiments and the comparative examples, the tilapia fry breeding test is performed.

1. Experimental materials:

the used fry is purchased from a young fish farm in Qiongvillage town of Rexi, Chengmei county, Hainan province, and the average body mass of the young fish is (1.89 +/-0.15) g/tail;

2. the experimental method comprises the following steps:

the selected test pond is located in Yong Lunang village in Jones mountain area of Haikou city in Hainan province, the length is 20m multiplied by the width is 5m, the thickness of sludge at the bottom of the pond is about 30cm, the depth of the pond is 1.5m, the water depth is kept 60cm at ordinary times, and water inlet and drainage are completed by using a submersible pump; 2d before the feeding, the water in the pond is pumped out to the depth of about 30cm, and the pond is fed twice after being fed with the full food at 9-10 am and 5-6 pm during the test period. Changing water once within 2-3 days, fishing out impurities on the water surface at random, keeping the water surface clean, and changing the feeding amount in time according to the change of the physique of the tilapia.

(1) Setting 7 experimental groups, wherein each group is provided with 3 repetitions, each repetition contains 15 tails of young tilapia, and taking conventional commercially available tilapia feed (15 parts of fish meal, 10 parts of bone meal, 30 parts of bean cakes, 25 parts of wheat bran, 18 parts of bean dregs, 1 part of premix and 1 part of salt) as a control group, and respectively and periodically measuring the following growth indexes:

i, measuring and recording the initial body mass of the fish body at the 1 st d of the culture period. Stopping feeding for two days, and starting feeding the tilapia after the tilapia is adapted to the pond environment. After 60 days of feeding, stopping feeding for 24 hours, counting the tails of the tilapia on the next day and weighing the total weight. And calculating the mass increase rate and the survival rate.

And II, randomly taking 3 tilapia mossambica with the body mass close to the average body mass, placing the tilapia mossambica on an ice box, measuring the body length and the body mass of the tilapia mossambica, and calculating the specific growth rate.

And III, taking internal organs and liver and pancreas, washing with precooled 0.85% physiological saline, drying by using filter paper, weighing, and calculating the liver body ratio, the internal organ ratio and the fullness.

Mass gain rate (WGR), Specific Growth Rate (SGR), liver body ratio (HSI), visceral body ratio (VSI), fullness (CF) and Survival (SR) were calculated by the following formulas.

Mass increase rate (WGR,%) - (W)_t-W₀)/W₀×100％

Specific growth rate (SGR,%) - (ln W)_t-ln W₀)/t×100％

Fullness (CF, g/cm)³)＝W_t/L³×100％

Liver function ratio (HSI,%) W_h/W×100％

Visceral volume ratio (VSI,%) W_v/W×100％

In the formula: w_tRepresents the weight (g), W of fish terminal body₀Represents the initial body mass (g) of the fish, t represents the experimental days, L represents the body length (cm) of the fish, W represents the body mass (g) of the fish_hRepresenting the liver mass (g), W of the fish body_vRepresents the visceral mass (g) of the fish body. The results are given in the following table:

as can be seen from the above table, the survival rate of the juvenile tilapia in examples 1 to 4 is stable, and the mass increase rate, the fullness, the visceral volume ratio, the liver volume ratio and the specific growth rate of the juvenile tilapia are significantly improved, wherein the liver of the juvenile tilapia is mauve, the liver volume ratio of the juvenile tilapia is increased and kept between 1% and 2%, which does not belong to the phenomenon of hepatomegaly, while the growth and development effect of the juvenile tilapia is reduced in example 5, the barbat skullcap extract is not added in comparative example 1, the liver volume ratio of part of the juvenile tilapia is excessively increased, and the specific growth rate of the whole juvenile tilapia is relatively reduced; the proportion of fish meal is reduced in the comparative example 2, and the growth index of juvenile tilapia is reduced, which shows that the invention adopts the duckweed dry powder to be compounded with the fish meal and the corn protein powder according to a certain proportion, so that the nutrition is more comprehensive, the quality increase rate, the fullness, the dirty body ratio and the specific growth rate of tilapia are effectively improved, the growth and development of tilapia fries are promoted, and the tilapia fries are bright in body color.

(2) Respectively measuring the influence of different feed formulas on digestive enzymes in liver and pancreas of tilapia in experimental groups 4-5 (examples 4-5) and experimental groups 6-7 (comparative examples 1-2), wherein the activities of protease, amylase and lipase are measured by adopting a kit provided by Nanjing institute of bioengineering, the reaction is carried out according to the steps of an instruction manual, a microplate reader is used for measurement, the results are shown as follows,

as can be seen from the above table, in example 4, the activity of digestive enzymes in liver and pancreas of tilapia is high, so that the fat metabolism rate in liver of tilapia with high dose of duckweed is ensured, the hepatomegaly phenomenon of fish body is avoided, the stable development of liver is promoted, and the risk of fatty liver is reduced. In the comparative example 1, the digestive enzymes in liver and pancreas of the tilapia are obviously reduced, which shows that the activity of the digestive enzymes in stomach, intestinal tract and liver and pancreas of the tilapia can be better regulated and controlled by adding the sculellaria barbata extract with a certain proportion to be combined with the duckweed dry powder, the secretion and activity of the digestive enzymes are promoted, and the utilization rate of the natural pigments such as proteins, vitamins and flavonoids in the duckweed dry powder is improved. Compared with example 4, the activity of digestive enzymes in liver and pancreas of tilapia is in a descending trend, which shows that the effective pretreatment of duckweed is beneficial to promoting the complete degradation of duckweed and ensuring the effective nutrient components of duckweed, so that the digestion and absorption of fry can be further promoted, the digestibility of the fry on feed can be improved, and the growth and development of liver of tilapia can be promoted.

(3) The invention also detects the stability, the nutritional ingredients, the microbiology and the heavy metal content of the tilapia feed formula for the experimental components, and the detection result shows that the tilapia feed formula meets the national standard, does not cause damage to fish bodies while fully meeting the nutritional requirements of tilapia, and is not easy to cause heavy metal pollution to the environment.

(4) The duckweed dry powder in example 4 and example 5 is independently sampled, and the main nutrient components of the duckweed dry powder are determined, and the determination results are shown in the following table:

as can be seen from the above table, in example 4, compared with example 5, the crude fat and crude protein content is significantly higher than that in example 5, the content of lysine and sulfur-containing amino acid is also increased, and the content of crude fiber is decreased, which indicates that the present invention uses a combination of physical steam explosion and deep degradation to more thoroughly degrade duckweed, so that the crude cellulose content in duckweed can be decreased, and simultaneously, the nutritional ingredients in duckweed can be ensured, so as to sufficiently increase the nutritional value of duckweed, and facilitate the complete digestion and absorption of feed by tilapia young fish.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.