Rhodotorula mucilaginosa and preparation method of biological feed fermented by same
By screening out the red yeast strain R1 suitable for fermentation of soybean meal and peanut meal, the problem of microbial deficiency in the prior art was solved, and the high nutritional value of fermented feed and the efficient fish growth effect were achieved.
Patent Information
- Application Number
- CN202411654964.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-19
- Publication Date
- 2025-02-25
AI Technical Summary
There are not many microorganisms suitable for processing soybean meal and peanut meal fermentation feed in the prior art, which leads to low quality of fermented feed and difficult to meet the growth needs of fish.
A new strain suitable for soybean meal and peanut meal fermentation was screened out: Rhodotorula mucilaginosa strain R1. The soybean meal or peanut meal was treated by fermentation to improve its nutritional value and use it to replace conventional feed.
By using jelly red yeast R1 to ferment soybean meal or peanut meal, the nutritional value of the feed and the digestion and absorption rate of protein are significantly improved, fish growth is promoted, the feed-to-meat ratio is reduced, and the feed utilization is improved.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of microorganisms, and in particular to a red yeast strain and a method for preparing a fermented biological feed thereof. Background Art
[0002] In recent years, with the rapid development of my country's aquaculture industry, the demand for high-protein feed has increased year by year. As fish feed, although oil meal is rich in protein and relatively cheap, there are some limiting factors. Among them, anti-nutritional factors are one of the main problems, such as phytic acid, trypsin inhibitors, etc., which will affect the absorption and utilization of nutrients by fish. The amino acid composition of different types of oil meal is not balanced enough, and the content of some essential amino acids is insufficient, which will limit the growth of fish. In order to overcome these shortcomings, heat treatment, addition of enzyme preparations, and combination with other protein sources are usually adopted.
[0003] By using a biological fermentation method to process soybean meal or peanut meal and then using it for feed processing, large molecular proteins can be hydrolyzed into small molecular peptides without destroying their nutritional components, thereby achieving the purpose of removing anti-nutritional factors, and at the same time having a positive effect on improving the nutritional value of soybean meal or peanut meal; however, there are not many microorganisms suitable for soybean meal and peanut meal fermentation feed processing in the current technology. In order to improve the quality of fermented feed, screening dominant strains for feed fermentation is an indispensable technical means in this field. Summary of the invention
[0004] In view of the above, it is necessary to screen out microorganisms suitable for fermentation of soybean meal and peanut meal to replace conventional feed, increase the nutritional value of feed and promote the development of the feed industry.
[0005] To achieve the above purpose, the present invention screened out a new strain: Rhodotorula mucilaginosa strain R1, which is classified and named as Rhodotorula mucilaginosa, and its Chinese classification name is: Rhodotorula mucilaginosa, and its preservation number is CCTCC NO: M20242268; the strain is deposited in the China Center for Type Culture Collection, address: Wuhan University, No. 299, Bayi Road, Wuchang District, Wuhan City, Hubei Province, and the preservation date is October 21, 2024.
[0006] The present invention also includes that the ITS sequence of the Rhodotorula mucilaginosa strain R1 is shown in SEQ ID NO:1.
[0007] The present invention also includes a bacterial agent comprising the Rhodotorula mucilaginosa strain R1.
[0008] The present invention also includes a feed comprising the Rhodotorula mucilaginosa strain R1.
[0009] The present invention also includes the use of the Rhodotorula mucilaginosa strain R1 or the bacterial agent in preparing feed.
[0010] The present invention also includes a method for preparing feed using the Rhodotorula mucilaginosa strain R1 or the bacterial agent, which comprises: activating the Rhodotorula mucilaginosa strain R1, inoculating it into soybean meal or peanut meal, fully mixing it, and then fermenting it to obtain the corresponding fermented soybean meal or fermented peanut meal; then replacing the soybean meal in the basic feed with the fermented soybean meal or replacing the peanut meal with the fermented peanut meal, and fully mixing them to obtain the feed.
[0011] Furthermore, the basic feed is composed of the following ingredients: 15-30 parts of fish meal, 18-28 parts of soybean meal, 15-25 parts of peanut meal, 10-20 parts of corn flour, 10-15 parts of high-gluten flour, 3-8 parts of shrimp shell meal, 2-5 parts of rice bran, 1-4 parts of fish oil, 0.1-1 parts of soybean lecithin, 1-3 parts of monocalcium phosphate, 0.3-1 parts of compound multivitamins, 0.1-0.5 parts of compound multi-minerals, 0.1-0.6 parts of choline chloride, and 0.1-0.5 parts of alpha starch.
[0012] The present invention also includes a method for feeding fish with the feed prepared by the method, which comprises: replacing peanut meal or soybean meal in a basic feed component with 15% by mass of fermented peanut meal or 15% by mass of fermented soybean meal, while keeping other components unchanged, and fully mixing the feed components for feeding fish.
[0013] Furthermore, the fish is tilapia.
[0014] The present invention has the following beneficial effects:
[0015] The red yeast R1 of the present invention is a microorganism selected by the applicant. It has been identified that the strain has a high high-salt tolerance and is suitable for producing fermented feed for aquaculture. Experimental research shows that the red yeast used in the fermented feed supplements the feed with active substances such as astaxanthin, thereby improving the nutritional value of the feed. In addition, after the soybean meal and peanut meal are fermented, macromolecular proteins are decomposed into small molecular peptides, thereby improving the digestion and absorption rate of the protein. After the soybean meal and peanut meal are fermented by the strain to replace the soybean meal and peanut meal of conventional feed, the feed compatibility is more scientific, the growth requirements of fish can be well met, the growth of fish can be significantly promoted, the feed utilization rate can be improved, and the feed-to-meat ratio can be reduced. The present invention is a good biological fermented feed for fish. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a plate culture picture of strain R1.
[0017] Figure 2 These are scanning electron microscope photos of strain R1, where A is magnified 10,000 times and B is magnified 20,000 times.
[0018] Figure 3 These are optical microscope photos of strain R1 stained with methylene blue, where A is magnified 400 times and B is magnified 1000 times.
[0019] Figure 4 This is the ITS phylogenetic tree of strain R1.
[0020] Figure 5 This is the growth curve of strain R1 under different temperature conditions.
[0021] Figure 6 This is the growth curve of strain R1 under different salinity conditions.
[0022] Figure 7 This is the growth curve of strain R1 under different pH conditions.
[0023] Figure 8 This is the change of acid-soluble protein content during the fermentation of soybean meal and peanut meal.
[0024] Fig. 9 The change in the number of live red yeast rice contained in soybean meal and peanut meal during the fermentation process.
[0025] Fig.10 This is a graph showing the differences in intestinal microbial flora diversity of tilapia in the fermented soybean meal 15% feed replacement group and the control group.
[0026] Fig.11 The difference in intestinal microbial flora diversity of tilapia in the fermented peanut meal 15% feed replacement group and the control group.
[0027] Biomaterial Deposit Information
[0028] The strain screened in this application is Rhodotorula mucilaginosa strain R1, which is classified and named as Rhodotorula mucilaginosa, and its Chinese classification name is Rhodotorula mucilaginosa. The preservation number is CCTCC NO: M20242268; the strain is deposited in the China Center for Type Culture Collection, address: Wuhan University, No. 299, Bayi Road, Wuchang District, Wuhan City, Hubei Province, and the preservation date is October 21, 2024. DETAILED DESCRIPTION
[0029] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.
[0030] Any feature disclosed in this specification (including any appended claims and abstract), unless otherwise stated, is merely an example of a series of equivalent or similar features.
[0031] Example 1
[0032] This example is a screening and identification method for strain R1, which is as follows:
[0033] 1. Screening method: Take seawater samples and inoculate them into YPD liquid culture medium at a ratio of 2% for enrichment for 48 hours. The enriched culture medium is diluted 10 times in a gradient manner. The original liquid, 10 times liquid, and 100 times liquid are diluted and coated on YPD solid plates. Culture at a constant temperature of 26-30℃. After the colonies grow, pick the colonies and streak them for purification.
[0034] 2. Strain identification:
[0035] ① Morphological identification Morphological identification such as Figure 1-Figure 3 As shown: Colony morphology Figure 1 As shown, the red yeast R1 was inoculated on the YPD medium and cultured. The colony was orange at the beginning, and the color gradually deepened in the later stage. The colony edge was clear and the surface was smooth. The results of scanning electron microscopy observation were as shown in Figure 2 As shown, Figure 2 Figure A is magnified 10,000 times, and Figure B is magnified 20,000 times. After staining with 1% methylene blue, the bacteria were observed to be round or oval under an optical microscope (see Figure 3 , Figure 3 Figure A is magnified 400 times, and Figure B is magnified 1000 times). The reproduction method is budding. Scanning electron microscopy observation showed that the size of the strain was (2.8-4.6) μm × (3.3-4.5) μm.
[0036] ② Biochemical identification: The physiological and biochemical characteristics of Rhodotorula R1 were identified by biochemical tube identification method. The specific method was as follows: the cultured R1 bacterial solution was connected to a biochemical identification tube (TH-15C yeast-like fungus biochemical identification tube produced by Hangzhou Binhe Microbiological Reagent Co., Ltd.), 25 μl of the tested bacterial solution was added to each biochemical tube using a pipette, and the tube was cultured at 35°C for 48 hours. The R1 was biochemically identified by the digital identification method.
[0037] As can be seen from Table 1, the digital identification result is 67703. After comparing with the reference book, the strain R1 was determined to be Rhodotorula glutinosus.
[0038] Table 1: Identification results of Rhodotorula glutinosus R1 using the Yeast-like Fungi Biochemical Identification Tube
[0039]
[0040] ③ Molecular identification of the strain: DNA of the strain was extracted according to conventional methods, and the universal primers ITS1: 5'-TCCGTAGGTGAACCTGCGG-3' and ITS4: 5'-TCCTCCGCTTATTGATATGC-3' of the ITS region of fungi were used to amplify the ITS region gene, wherein the amplified ITS sequence is shown in SEQ ID NO: 1, and the sequence was compared with the GenBank library in the National Center for Biotechnology Information (NCBI) database of the United States for BLAST analysis, and the results were compared for phylogenetic analysis, and the phylogenetic tree was established by the maximum likelihood method. The phylogenetic analysis results are shown in Figure 4 shown.
[0041] Based on the above morphological identification, biochemical identification and molecular biology results, it can be determined that the strain belongs to the genus Rhodotorula. The results of molecular biological identification show that its closest relationship is Rhodotorula mucilaginosa. We named this strain Rhodotorula mucilaginosa R1.
[0042] Example 2
[0043] The physiological characteristics of the screened red yeast R1 were studied, and the specific methods are as follows:
[0044] 1. Temperature tolerance:
[0045] Set different temperature gradients, inoculate the red yeast R1 culture medium at a ratio of 2%, culture at different temperatures, and measure the OD of the culture solution. 600 , draw a growth curve.
[0046] The results are as follows Figure 5 As shown by Figure 5 It can be seen that the optimal growth temperature of Rhodotorula glutinosus R1 is 26-35°C. At 20°C, the growth rate of Rhodotorula glutinosus R1 is inhibited, and at 50°C, Rhodotorula glutinosus R1 cannot grow. This indicates that the strain Rhodotorula glutinosus R1 has a weak tolerance to temperature.
[0047] 2. Salinity tolerance:
[0048] Prepare YPD liquid culture medium with different percentages of NaCl concentration, sterilize at 121℃ for 20min, add the activated red yeast R1 culture medium at 2% to the YPD culture medium, set up three parallels for each salinity, shake culture at 28℃, and measure the OD of the culture solution 600 , draw a growth curve. The YPD medium components are: 20g tryptone, 10g yeast extract, 20g sodium chloride, 20g glucose, pH 6.8-7.2, and 1L pure water.
[0049] The results are as follows Figure 6 As shown by Figure 6 It can be seen that the strain Rhodotorula R1 has a strong tolerance to salinity; and the growth rate of Rhodotorula R1 is not significantly different in the salinity range of 0‰-120‰, and the growth rate is inhibited in the salinity range above 140‰, indicating that the strain Rhodotorula R1 has the physiological characteristics of high salt tolerance.
[0050] 3. Acid and alkali tolerance:
[0051] Liquid YPD medium was prepared, and the medium was adjusted to different pH values with glacial acetic acid and NaOH, respectively, and sterilized at 121℃ for 20 min. The red yeast R1 culture liquid was inoculated into the above conditioned medium at a ratio of 2%, and three groups of parallel culture were performed for each pH value. The culture liquid was shaken at 28℃ and the OD of the culture liquid was measured. 600 , draw a growth curve.
[0052] The results are as follows Figure 7 As shown by Figure 7 It can be seen that the growth rate of Rhodotorula glutinosus R1 is fastest between pH 6-9, and there is no significant difference. The growth rate is inhibited at pH 10, and the growth is significantly inhibited at pH 3-4.
[0053] Example 3
[0054] The selected red yeast R1 is used to prepare fermented biological feed, as follows:
[0055] 1. Fermented feed preparation method:
[0056] ① Fermented soybean meal: Evenly mix the activated red yeast liquid with the dried sterilized soybean meal in a material-water ratio of 1:1, and put it into a fermentation tank for fermentation. The fermentation temperature is 30°C, the humidity is not less than 80%, and the fermentation time is 5 days. After the fermentation is completed, the fermented soybean meal is dried and crushed, and passed through an 80-mesh sieve for later use.
[0057] ② Fermented peanut meal: Mix the activated red yeast liquid and the dried sterilized peanut meal in a material-water ratio of 1:1, and put them into a fermentation tank for fermentation. The fermentation temperature is 30°C, the humidity is not less than 80%, and the fermentation time is 5 days. After the fermentation is completed, the fermented soybean meal is dried and crushed, and passed through an 80-mesh sieve for later use.
[0058] 2. Verification of the fermentation effect of fermented feed:
[0059] ① Changes in the content of acid-soluble protein in soybean meal and peanut meal during fermentation: The acid-soluble protein content of fermented soybean meal and peanut meal was determined in accordance with the national standard for the determination of acid-soluble protein in feed raw materials (Agricultural Industry Standard of the People's Republic of China, Determination of Acid-soluble Protein in Feed Raw Materials NY / T 3801-2020).
[0060] The results are as follows Figure 8 As shown by Figure 8 It can be seen that the acid-soluble protein content of soybean meal and peanut meal increased with the fermentation time during the fermentation process and reached the highest on the 7th day. Since the difference in acid-soluble protein content between 5 and 7 days was not significant, considering the cost issue, the fermentation time was selected as 5 days.
[0061] ② Changes in the amount of live bacteria contained in soybean meal and peanut meal during fermentation: The statistical method for the live bacteria content of Rhodotorula glutinosus during fermentation is the dilution plate spreading method. The specific operation is to take 0.1g of fermented soybean meal or peanut meal and mix it evenly with 0.9ml of water, take 0.1ml of the mixture for dilution and spreading, set up three parallel groups for each group, and count the number of live bacteria of Rhodotorula glutinosus in the fermentation raw materials.
[0062] The results are as follows Fig. 9 As shown by Fig. 9 It can be seen that during the fermentation process, the number of live bacteria in fermented soybean meal and fermented peanut meal reached the highest value (>1×10 8 CFU / g, then began to decline and stabilized after 7 days (>1×10 7 CFU / g).
[0063] Combined with the above experimental results, we concluded that the specific preparation method of fermented feed is:
[0064] ① Preparation method of fermented soybean meal feed: replace 15% of the soybean meal in the basic feed components with fermented soybean meal, and keep the other components unchanged. Mix the various components of the feed thoroughly, and put the feed raw materials into a feed machine (Hebei Norda Machinery) to make feed. After the feed is made, it is dried indoors. After drying, add vegetable oil at a ratio of 1%-3% and mix evenly with the feed to obtain fermented soybean meal feed.
[0065] ② Preparation method of fermented peanut meal feed: replace 15% of the peanut meal in the basic feed components with fermented peanut meal, and keep the other components unchanged. Mix the various components of the feed thoroughly, and put the feed raw materials into a feed machine (Hebei Norda Machinery) to make feed. After the feed is made, dry it indoors. After drying, add vegetable oil at a ratio of 1%-3% and mix it evenly to make fermented peanut meal feed.
[0066] The basic feed raw material components are: 15-30 parts of fish meal, 18-28 parts of soybean meal, 15-25 parts of peanut meal, 10-20 parts of corn flour, 10-15 parts of high-gluten flour, 3-8 parts of shrimp shell powder, 2-5 parts of rice bran, 1-4 parts of fish oil, 0.1-1 parts of soybean lecithin, 1-3 parts of calcium dihydrogen phosphate, 0.3-1 parts of compound multivitamins, 0.1-0.5 parts of compound multiminerals, 0.1-0.6 parts of choline chloride, and 0.1-0.5 parts of alpha starch. Each feed raw material is dried and crushed, and then sieved through an 80-mesh sieve for use.
[0067] The above-mentioned compound multivitamin is a mixed liquid of vitamin B1, vitamin B2, and vitamin B6; it was purchased from Guangzhou Zhengge Agriculture and Animal Husbandry Service Co., Ltd.; the compound multi-mineral is a compound of Ca, Mg, Fe, Mn, Zn, P, K, Na, and Co mineral elements; it was purchased from Shanxi Yifei Biotechnology Co., Ltd.
[0068] Example 4
[0069] This example is a method for conducting animal experiments using the feed prepared in Example 3, specifically:
[0070] The above feeds were used to feed tilapia. The specific breeding experiment was as follows: the experimental fish was Nile tilapia, with an initial body weight of 3.72±0.13 g. Three parallel groups were set up, with 30 fish in each group. The breeding experiment lasted for 56 days. After the experiment, the growth performance indicators of tilapia in each group were counted.
[0071] 1. Tilapia growth performance index detection, the specific results are shown in Table 2:
[0072] The calculation formula for tilapia growth performance related indicators is as follows:
[0073] Initial average weight = initial weight of experimental fish / number of experimental fish.
[0074] Final average weight = final weight of experimental fish / number of experimental fish.
[0075] Weight gain rate WGR = [(W end - W initial) / W initial] × 100%.
[0076] Specific growth rate SGR = (lnW end - lnW beginning) / D×100%.
[0077] Feed coefficient % = [feed amount / (final body weight-initial body weight)×100%]; wherein, the final body weight and initial body weight are both the average body weight of each group.
[0078] The feed components of the control group in this example are: 15 parts of fish meal, 18 parts of soybean meal, 15 parts of peanut meal, 10 parts of corn flour, 10 parts of high-gluten flour, 3 parts of shrimp shell meal, 2 parts of rice bran, 1 part of fish oil, 1 part of soybean lecithin, 1 part of monocalcium phosphate, 0.3 parts of compound multivitamins, 0.1 parts of compound multiminerals, 0.1 parts of choline chloride, and 0.5 parts of alpha starch.
[0079] The feed components of the fermented soybean meal replacement feed group with a mass percentage of 15%-45% are: fermented soybean meal with a mass percentage of 15%-45% and: basic feed 1 with a mass percentage of 55%-85%; wherein the basic feed 1 consists of 15 parts of fish meal, 15 parts of peanut meal, 10 parts of corn flour, 10 parts of high-gluten flour, 3 parts of shrimp shell meal, 2 parts of rice bran, 1 part of fish oil, 1 part of soybean lecithin, 1 part of monocalcium phosphate, 0.3 parts of compound multivitamins, 0.1 parts of compound multiminerals, 0.1 parts of choline chloride and 0.5 parts of alpha starch.
[0080] The feed components of the fermented peanut meal replacement feed group with a mass percentage of 15%-45% are: fermented peanut meal with a mass percentage of 15%-45% and basic feed 2 with a mass percentage of 55%-85%; wherein the basic feed 2 is composed of 15 parts of fish meal, 18 parts of soybean meal, 10 parts of corn flour, 10 parts of high-gluten flour, 3 parts of shrimp shell meal, 2 parts of rice bran, 1 part of fish oil, 1 part of soybean lecithin, 1 part of monocalcium phosphate, 0.3 parts of compound multivitamins, 0.1 parts of compound multiminerals, 0.1 parts of choline chloride and 0.5 parts of alpha starch.
[0081] Table 2 shows the effect of disease-resistant biological feed on the growth performance of tilapia
[0082]
[0083] Note: “*” indicates significant difference compared with the control group (P<0.05).
[0084] It can be seen from Table 2 that the final average weight, weight gain rate and specific growth rate of the fermented soybean meal 15% replacement feed group and the fermented peanut meal 15% replacement feed group were significantly higher than those of the control group, and the feed coefficient of the fermented soybean meal 15% replacement feed group and the fermented peanut meal 15% replacement feed group was significantly lower than that of the control group, which indicates that the fermented soybean meal 15% replacement feed group and the fermented peanut meal 15% replacement feed group can significantly improve the growth performance of tilapia and improve feed utilization.
[0085] 2. Changes in the diversity of tilapia intestinal microbial flora. For specific results, see Figure 10-11 As shown:
[0086] Depend on Fig.10It can be seen that in the group where fermented soybean meal replaced 15% of the feed, the abundance of heterotrophic strains of Acinetobacter, Pseudomonas, Turicibacter, etc., which have no probiotic function and may be pathogenic bacteria, was significantly reduced, which reduced the energy consumption of microorganisms in the intestine and improved the fish's absorption efficiency of feed.
[0087] Depend on Fig.11 It can be seen that in the group where fermented peanut meal replaced 15% of feed, the abundance of heterotrophic strains such as Turicibacter and Alsobacter, which have no probiotic function and may be pathogenic bacteria, was significantly reduced, while the abundance of probiotics such as Paracoccus, Pseudonocardia, and Lactococcus, or bacteria with potential probiotic properties, was significantly increased, which increased the fish's feed absorption efficiency while increasing the abundance of probiotics and improving the intestinal health of fish.
[0088] In summary, the red yeast R1 of the present invention has been identified to have high high-salt tolerance and is suitable for producing fermented feed for aquaculture. Experimental studies have shown that the red yeast used in the fermented feed supplements the feed with active substances such as astaxanthin, thereby improving the nutritional value of the feed, and can well meet the growth needs of fish, significantly promote the growth of fish, improve feed utilization, and reduce the feed-to-meat ratio. The present invention is a good biological fermented feed for fish.
[0089] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.
Claims
1. Rhodotorula mucilaginosa strain R1, whose deposit number is CCTCC NO: M20242268.
2. The ITS sequence of the Rhodotorula mucilaginosa strain R1 as claimed in claim 1 is shown in SEQ ID NO:
1.
3. A bacterial agent comprising the Rhodotorula mucilaginosa strain R1 according to any one of claims 1 or 2.
4. A feed comprising the Rhodotorula mucilaginosa strain R1 according to claim 1.
5. Use of the Rhodotorula mucilaginosa strain R1 according to any one of claims 1 or 2 or the bacterial agent according to claim 3 in preparing feed.
6. A method for preparing feed using the Rhodotorula mucilaginosa strain R1 as claimed in any one of claims 1 or 2 or the bacterial agent as claimed in claim 3, characterized in that: The method comprises the following steps: activating the Rhodotorula mucilaginosa strain R1, inoculating it into soybean meal or peanut meal, fully mixing it, and then fermenting it to obtain the corresponding fermented soybean meal or fermented peanut meal; and then replacing the soybean meal with fermented soybean meal or replacing the peanut meal with fermented peanut meal in the basic feed, and fully mixing them to obtain the feed.
7. The method according to claim 6, characterized in that The basic feed is composed of the following ingredients: 15-30 parts of fish meal, 18-28 parts of soybean meal, 15-25 parts of peanut meal, 10-20 parts of corn flour, 10-15 parts of high-gluten flour, 3-8 parts of shrimp shell meal, 2-5 parts of rice bran, 1-4 parts of fish oil, 0.1-1 parts of soybean lecithin, 1-3 parts of monocalcium phosphate, 0.3-1 parts of compound multivitamins, 0.1-0.5 parts of compound multiminerals, 0.1-0.6 parts of choline chloride, and 0.1-0.5 parts of alpha starch.
8. A method for raising fish using the feed prepared by the method of claim 6 or 7, characterized in that: The method comprises the following steps: replacing peanut meal or soybean meal in a basic feed component with 15% by mass of fermented peanut meal or 15% by mass of fermented soybean meal, while keeping other components unchanged, and fully mixing the feed components for feeding fish.
9. The method according to claim 8, characterized in that The fish is tilapia.