Feed additive for improving starch utilization rate of micropterus salmoides and preparation method

Abstract

The invention relates to a feed additive for improving the starch utilization rate of micropterus salmoides and a preparation method, and belongs to the technical field of feeds, the feed additive comprises the following raw materials: stevia rebaudiana, mussel powder, fructus hippophae, jerusalem artichoke, pumpkin seeds, mulberry leaves and a complex microbial inoculant; the complex microbial inoculant comprises lactobacillus reuteri, lactobacillus plantarum and EM bacteria. The stevia rebaudiana, the greenlip mussel powder and the Arabic gum added in the feed additive disclosed by the invention are started from improving the taste sense and smell sense and improving the biting requirements, and the prepared feed additive finished product has outstanding food calling performance under the synergistic effect; the added lactobacillus reuteri, lactobacillus plantarum and EM bacteria have a synergistic effect, so that the prepared feed additive has a high starch utilization effect; the added sea buckthorn fruits, jerusalem artichoke, pumpkin seeds and mulberry leaves can be started from enhancing immunity, promoting growth and reproduction of beneficial bacteria, removing food retention and regulating physiological functions, and the prepared feed additive finished product has an extremely good growth promoting effect through synergistic effects of the sea buckthorn fruits, the jerusalem artichoke, the pumpkin seeds and the mulberry leaves.

Description

Technical Field

[0001] The invention belongs to the technical field of feed, and in particular relates to a feed additive for improving starch utilization rate of California sea bass and a preparation method thereof. Background Art

[0002] As an important high-quality freshwater farmed fish, California bass occupies a prominent position in the aquaculture industry. Its meat is delicious and nutritious, and it is deeply loved by consumers, and the market demand continues to grow. However, California bass has relatively stringent requirements on feed ingredients in terms of digestive physiology. Traditional California bass feed is mainly carnivorous, that is, it mainly eats various small fish, shrimps, young frogs, aquatic and terrestrial insects and larvae that are high in protein and fat. Because California bass has a relatively strong ability to utilize protein and fat, but a low utilization rate of carbohydrates (especially starch), its digestive system has adapted to high-protein and high-fat food sources, and the secretion of digestive enzymes for starch substances is relatively insufficient. In addition, its sugar metabolism pathway in the body is not perfect, which can easily affect the feeding enthusiasm and growth performance of California bass itself.

[0003] With the continuous expansion of aquaculture, more and more feed varieties are emerging on the market, but there are very few varieties of these feeds that can improve starch utilization, attract appetite and promote growth. Therefore, it is of great practical significance to provide a feed additive and preparation method that can solve the above-mentioned feed problems. Summary of the invention

[0004] The purpose of the present invention is to provide a feed additive for improving the utilization rate of starch by California sea bass and a preparation method thereof, so as to solve the problems of low starch utilization rate and poor feeding and growth-promoting effects existing in the prior art.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A feed additive for improving starch utilization of California sea bass, the feed additive specifically comprising the following raw materials in parts by weight:

[0007]

[0008] As a preferred technical solution of the present invention, the composite bacterial agent includes Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria.

[0009] Furthermore, the mass ratio of Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria is 1-1.5:2-4:2-3.

[0010] Furthermore, the total viable count of Lactobacillus reuteri is 1×10 11 CFU / g, the total viable count of Lactobacillus plantarum is 1×10 12CFU / g, the total viable count of EM bacteria is 1×10 7 CFU / g.

[0011] As a preferred technical solution of the present invention, the stevia (Stevia rebaudiana) is a perennial herb of the Asteraceae family and the genus Stevia; the green-lipped mussel powder is purchased from Xi'an Wanlv Biotechnology Co., Ltd.; the seabuckthorn fruit is the fruit of the seabuckthorn plant of the genus Seabuckthorn of the Elaeagnaceae family; the Jerusalem artichoke (Helianthus tuberosus L.) is a perennial perennial herb of the Asteraceae family and the genus Helianthus; the pumpkin seeds are the seeds of the pumpkin (Cucurbita moschata Duch.) of the genus Cucurbitaceae; and the mulberry leaves are the dried leaves of the mulberry plant of the Moraceae family.

[0012] As a preferred technical solution of the present invention, the feed additive also includes gum arabic.

[0013] Furthermore, the gum arabic is 15-25 parts by weight.

[0014] A method for preparing a feed additive for improving starch utilization of California sea bass specifically comprises the following steps:

[0015] S1. Mix stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves evenly, add deionized water to control the temperature and boil, filter, set the filtrate aside, take the filter residue and boil it again once, filter again, combine the two filter residues and filtrate respectively, to obtain the boiled filtrate and the boiled filter residue; concentrate the boiled filtrate, control the temperature and dry it, crush it, sieve it, and obtain a mixture A; crush the boiled filter residue, sieve it, and obtain a mixture B; mix the mixture A and the mixture B evenly to obtain a mixture C;

[0016] S2. Add deionized water to gum arabic to prepare gum arabic liquid; mix mixture C, green-lipped mussel powder, gum arabic liquid and composite bacterial agent evenly and granulate them to obtain a finished feed additive.

[0017] As a preferred technical solution of the present invention, the amount of deionized water added in step S1 is 20-30 times the total mass of stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves; the temperature of the temperature-controlled boiling is 98-100°C, and the time is 1.5-2h; the concentration is concentrated to 1 / 4-1 / 3 of the original volume; the temperature of the temperature-controlled drying is 75-80°C; and the screening is through a 600-800 mesh sieve.

[0018] As a preferred technical solution of the present invention, the mass concentration of the gum arabic solution in step S2 is 3-5%; and the rotation speed of the granulation is 700-800 rpm.

[0019] The invention discloses an application of a feed additive for improving starch utilization rate of California bass, wherein the feed additive is added into fish feed as one of raw materials.

[0020] As a preferred technical solution of the present invention, the addition amount of the feed additive is 1.5-2% of the total weight of fish feed.

[0021] Beneficial effects of the present invention:

[0022] (1) The Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria added in the present invention can synergistically make the prepared feed additive have a high starch utilization effect. Specifically, Lactobacillus reuteri produces digestive enzymes such as amylase to decompose starch; Lactobacillus plantarum affects the decomposition and metabolism of fat to improve the utilization of starch in the feed by fish; EM bacteria provides efficient metabolism to convert starch, protein and other components in the feed into polysaccharides, fatty acids and other substances that are easier for fish to absorb; therefore, the three strains can synergistically increase the utilization rate of starch in the finished product.

[0023] (2) The present invention adds stevia with higher sweetness to improve palatability, thereby increasing the attractiveness of the feed additive to aquatic animals from the perspective of taste; adds green-lipped mussel powder containing amino acid components to stimulate the olfactory nerves of aquatic animals and increase the response of aquatic animals to odors; adds gum arabic to increase the toughness and elasticity of the feed, so that the feed can maintain a certain shape in water and will not easily fall apart when bitten by fish, thereby satisfying the biting needs of fish; therefore, the feed additive product prepared thereby has an excellent food attractant effect.

[0024] (3) The seabuckthorn fruit added in the present invention contains a large amount of flavonoids, vitamin C, carotenoids and other nutrients, which can enhance the immunity of aquatic animals and reduce the impact of diseases on growth; the added Jerusalem artichoke is rich in ingredients such as inulin, which can promote the growth and reproduction of beneficial bacteria and inhibit the survival of harmful bacteria; the added pumpkin seeds can eliminate accumulation and stimulate gastrointestinal motility; the added mulberry leaves can regulate the physiological functions of aquatic animals with the biologically active substances they contain, thereby better utilizing feed; therefore, the seabuckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves selected in the present invention can enhance immunity, promote the growth and reproduction of beneficial bacteria, eliminate accumulation, and regulate physiological functions, and synergistically make the prepared feed additive product have an excellent growth-promoting effect. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The stevia used in the embodiment of the present invention is a perennial herbaceous plant of the genus Stevia in the family Asteraceae; the green-lipped mussel powder used is purchased from Xi'an Wanlv Biotechnology Co., Ltd.; the seabuckthorn fruit is the fruit of the seabuckthorn plant of the genus Seabuckthorn in the family Elaeagnaceae; the Jerusalem artichoke (Helianthus tuberosus L.) used is a perennial perennial herbaceous plant of the family Asteraceae and the genus Helianthus; the pumpkin seeds used are the seeds of the pumpkin (Cucurbita moschata Duch.) of the family Cucurbitaceae; the mulberry leaves used are the dried leaves of the mulberry plant of the family Moraceae; the total viable count of the Lactobacillus reuteri used is 1×10 11 CFU / g, the total viable count of Lactobacillus plantarum is 1×10 12 CFU / g, the total viable count of EM bacteria is 1×10 7 CFU / g; the above, no further elaboration will be given later.

[0027] Example 1

[0028] A feed additive for improving starch utilization of California sea bass, the feed additive specifically comprising the following raw materials in parts by weight:

[0029]

[0030] The composite bacterial agent comprises Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria in a mass ratio of 1.3:2:3.

[0031] A method for preparing a feed additive for improving starch utilization of California sea bass specifically comprises the following steps:

[0032] S1. Mix stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves evenly, add deionized water and control the temperature at 98°C to boil for 2h, filter, set the filtrate aside, take the filter residue and repeat the water boiling once, filter again, combine the filter residue and filtrate twice, respectively, to obtain the boiled filtrate and the boiled filter residue; concentrate the boiled filtrate to 1 / 4 of the original volume, control the temperature at 80°C to dry, crush, and pass through a 600-mesh sieve to obtain a mixture A; crush the boiled filter residue, pass through a 600-mesh sieve to obtain a mixture B, mix the mixture A and the mixture B evenly to obtain a mixture C;

[0033] The amount of deionized water added is 25 times the total mass of stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves;

[0034] S2, adding deionized water to the gum arabic to prepare a gum arabic solution with a mass concentration of 3%; mixing the mixture C, green-lipped mussel powder, the gum arabic solution and the composite bacterial agent evenly and granulating them to obtain a finished feed additive;

[0035] The rotation speed of the granulation is 750 rpm;

[0036] The feed additive prepared in this example was used as one of the raw materials and added into the fish feed at 2% of the total weight of the fish feed.

[0037] Example 2

[0038] A feed additive for improving starch utilization of California sea bass, the feed additive specifically comprising the following raw materials in parts by weight:

[0039]

[0040] The composite bacterial agent comprises Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria in a mass ratio of 1:3:2.5.

[0041] A method for preparing a feed additive for improving starch utilization of California sea bass specifically comprises the following steps:

[0042] S1. Mix stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves evenly, add deionized water and control the temperature at 100° C. to boil for 1.5 h, filter, set the filtrate aside, take the filter residue and repeat boiling once, filter again, combine the two filter residues and filtrate respectively, and obtain the boiled filtrate and boiled filter residue; concentrate the boiled filtrate to 1 / 3 of the original volume, control the temperature at 75° C. to dry, crush, and pass through a 700-mesh sieve to obtain a mixture A; crush the boiled filter residue, pass through an 800-mesh sieve to obtain a mixture B, and mix the mixture A and the mixture B evenly to obtain a mixture C;

[0043] The amount of deionized water added is 20 times the total mass of stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves;

[0044] S2, adding deionized water to the gum arabic to prepare a gum arabic solution with a mass concentration of 4%; mixing the mixture C, green-lipped mussel powder, the gum arabic solution and the composite bacterial agent evenly and granulating them to obtain a finished feed additive;

[0045] The rotation speed of the granulation is 800 rpm;

[0046] The feed additive prepared in this example was used as one of the raw materials and added into the fish feed at 1.5% of the total weight of the fish feed.

[0047] Example 3

[0048] A feed additive for improving starch utilization of California sea bass, the feed additive specifically comprising the following raw materials in parts by weight:

[0049]

[0050] The composite bacterial agent comprises Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria in a mass ratio of 1.5:4:2.

[0051] A method for preparing a feed additive for improving starch utilization of California sea bass specifically comprises the following steps:

[0052] S1. Mix stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves evenly, add deionized water and control the temperature at 99°C to boil for 2h, filter, set the filtrate aside, take the filter residue and repeat the water boiling once, filter again, combine the filter residue and filtrate twice, respectively, to obtain the boiled filtrate and the boiled filter residue; concentrate the boiled filtrate to 1 / 3 of the original volume, control the temperature at 77.5°C to dry, crush, and pass through an 800-mesh sieve to obtain a mixture A; crush the boiled filter residue, pass through a 700-mesh sieve to obtain a mixture B, mix the mixture A and the mixture B evenly to obtain a mixture C;

[0053] The amount of deionized water added is 30 times the total mass of stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves;

[0054] S2, adding deionized water to the gum arabic to prepare a gum arabic solution with a mass concentration of 5%; mixing the mixture C, green-lipped mussel powder, the gum arabic solution and the composite bacterial agent evenly and granulating them to obtain a finished feed additive;

[0055] The rotation speed of the granulation is 700 rpm;

[0056] The feed additive prepared in this example was used as one of the raw materials and added into the fish feed at 1.5% of the total weight of the fish feed.

[0057] Comparative Example 1

[0058] Compared with Example 3, the difference is that Lactobacillus reuteri is not added to the composite bacterial agent of Comparative Example 1, the composite bacterial agent includes Lactobacillus plantarum and EM bacteria in a mass ratio of 4.7:2.8, and the other operating steps and parameters remain unchanged.

[0059] Comparative Example 2

[0060] Compared with Example 3, the difference is that no plant lactobacillus is added to the composite bacterial agent of Comparative Example 2, the composite bacterial agent includes Lactobacillus reuteri and EM bacteria in a mass ratio of 3.5:4, and the other operating steps and parameters remain unchanged.

[0061] Comparative Example 3

[0062] Compared with Example 3, the difference is that no EM bacteria is added to the composite bacterial agent of Comparative Example 3, the composite bacterial agent includes Lactobacillus reuteri and Lactobacillus plantarum in a mass ratio of 2.5:5, and the other operating steps and parameters remain unchanged.

[0063] Comparative Examples 4-6

[0064] Compared with Example 3, the difference is that the weight portions of stevia, green-lipped mussel powder and gum arabic in Comparative Examples 4-6 are as shown in Table 1, and the other operating steps and parameters remain unchanged.

[0065] Table 1

[0066] Stevia (weight parts) Green lipped mussel powder (weight parts) Gum Arabic (parts by weight) Comparative Example 4 0 26 31 Comparative Example 5 29.5 0 27.5 Comparative Example 6 32 25 0

[0067] Comparative Examples 7-10

[0068] Compared with Example 3, the difference is that the weight portions of the spinosa fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves in Comparative Examples 7-10 are as shown in Table 2, and the other operating steps and parameters remain unchanged.

[0069] Table 2

[0070] Sea buckthorn fruit (weight) Jerusalem artichoke (weight parts) Pumpkin seeds (weight) Mulberry leaf (weight parts) Comparative Example 7 0 23.4 27.3 29.3 Comparative Example 8 27.3 0 25.4 27.3 Comparative Example 9 28.6 22.8 0 28.6 Comparative Example 10 29.3 23.4 27.3 0

[0071] Test Example 1

[0072] (1) Experimental site: A branch river in Yangdong District, Yangjiang City, Guangdong Province, where the fish are mainly mountain fish. A river section with a water depth of about 35 cm, a gentle current, and a river bottom mainly composed of sand and gravel was selected to set up a fish collecting screen. The fish inlet of the fish collecting screen must be equipped with inverted whiskers to prevent the fish entering the fish collecting screen from escaping.

[0073] (2) Test method: 36 pits were dug at the test site to fit the fish collecting sieves. The fish collecting sieves were placed. While ensuring that there was no obstruction at the inverted opening of the fish collecting sieves, the fish collecting sieves were covered with sand and stones. The 36 fish collecting sieves were buried in a 6×6 Latin square array, wherein each fish collecting sieve was 2 m apart. Then, 36 workers simultaneously placed the same mass of fish feeds prepared in Examples 1-3 and Comparative Examples 4-6 in the 36 fish collecting sieves in a 6×6 Latin square array. The arrangement of the 36 fish collecting sieves is shown in Table 3:

[0074] The Latin square is arranged as shown in Table 3:

[0075] Table 3

[0076]

[0077] After the feed was released, the timing started, and the operator left the test site. After 15 minutes, the fish sieves were collected and the number of fish in the fish sieves (number of tails) was recorded respectively. The type of fish feed attracted more fish to feed, which was used to reflect the feeding results. The test results are shown in Table 4.

[0078] Table 4

[0079]

[0080] From Table 4, it can be seen that the fish feeds prepared in Examples 1-3 attracted 129, 125, and 134 fish respectively, while the fish feeds prepared in Comparative Examples 6-8 attracted 92, 90, and 101 fish respectively, which shows that the feed additive product prepared in the present invention has an excellent food attractant effect. This is because the stevia, green-lipped mussel powder, and gum arabic added in the present invention improve the taste, smell, and chewing needs, and the synergistic effect makes the prepared feed additive product have outstanding food attractant performance.

[0081] Test Example 2

[0082] The California bass seedlings with good vitality, weight of 3.5-4.7g (average weight of 4.0g), and body length of 5-6cm (average body length of 5.6cm) purchased from the same batch were randomly distributed into 10 cubic water pools with a side length of 1.5m, with 120 fish in each pool; after the seedlings were placed in the pools, water earthworms and fresh fish paste were fed for 7 days from the second day for domestication, and the dry weight of the feed fed during the domestication period accounted for 4% of the feeding amount during the entire breeding period. After the domestication was completed, the fish feed prepared by Examples 1-3, Comparative Examples 1-3 and Comparative Examples 7-10 was fed into 7 water pools respectively, and the feeding was regular 3 times a day (8:00, 12:00, 17:00) until the fish were full. The feces were removed and the residual bait was sucked out before feeding every day. The water was changed once, and the dissolved oxygen was maintained above 4.0 mg / L by microporous aeration for 24 hours every day. The test water was fully aerated tap water with a water temperature of (20-23)°C. The test period was 140 days. After the test was completed, the survival rate and average weight of catfish in each pond were checked; the results are shown in Table 5.

[0083] Table 5

[0084]

[0085]

[0086] It can be seen from Table 5 that after 140 days of feeding the fish feed prepared by Examples 1-3 of the present invention, the average weight of the California bass increased more and the survival rate was better than that of the fish feed prepared by Comparative Examples 1-3 and Comparative Examples 7-10.

[0087] Improving starch utilization can effectively improve the growth of fish, so that the average weight gain of fish is high; from the comparison of the data of Examples 1-3 and Comparative Examples 1-3, it can be seen that the survival rate of Comparative Examples 1-3 is low and the average weight gain is not as good as that of the Examples; but from the comparison of the data of Comparative Examples 1-3 and Comparative Examples 7-10, it can be found that even though the survival rate of Comparative Examples 1-3 is low and the average weight gain is not as good as that of the Examples, the survival rate and average weight gain of Comparative Examples 4-6 are higher than those of Comparative Examples 7-10, indicating that the Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria added in the present invention can synergistically make the prepared feed additive have a high starch utilization effect, thereby increasing the average weight of fish;

[0088] From the comparison of the data of Examples 1-3 and Comparative Examples 7-10, it can be seen that the survival rate and average weight gain of Comparative Examples 7-10 are both low, indicating that the feed additive prepared by the present invention has an outstanding growth-promoting effect. This is because the seabuckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves added by the present invention can enhance immunity, promote the growth and reproduction of beneficial bacteria, eliminate accumulation, and regulate physiological functions, and the synergistic effect makes the prepared feed additive product have an excellent growth-promoting effect.

[0089] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0090] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A feed additive for improving starch utilization of California sea bass, characterized in that: The feed additive specifically comprises the following raw materials in parts by weight:

2. The feed additive for improving starch utilization of California sea bass according to claim 1, characterized in that: The composite bacterial agent comprises Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria.

3. The feed additive for improving starch utilization of California sea bass according to claim 2, characterized in that: The mass ratio of the Lactobacillus reuteri, Lactobacillus plantarum and EM bacteria is 1-1.5:2-4:2-3.

4. The feed additive for improving starch utilization of California sea bass according to claim 2, characterized in that: The total viable count of Lactobacillus reuteri is 1×10 11 CFU / g, the total viable count of Lactobacillus plantarum is 1×10 12 CFU / g, the total viable count of EM bacteria is 1×10 7 CFU / g.

5. The feed additive for improving starch utilization of California sea bass according to claim 1, characterized in that: The feed additive also includes gum arabic.

6. The feed additive for improving starch utilization of California sea bass according to claim 5, characterized in that: The gum arabic is 15-25 parts by weight.

7. A method for preparing a feed additive for improving starch utilization of California sea bass according to any one of claims 5 to 6, characterized in that: The specific steps include: S1. Mix stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves evenly, add deionized water to control the temperature and boil, filter, set the filtrate aside, take the filter residue and boil it again once, filter again, combine the two filter residues and filtrate respectively, to obtain the boiled filtrate and the boiled filter residue; concentrate the boiled filtrate, control the temperature and dry it, crush it, sieve it, and obtain a mixture A; crush the boiled filter residue, sieve it, and obtain a mixture B; mix the mixture A and the mixture B evenly to obtain a mixture C; S2. Add deionized water to gum arabic to prepare gum arabic liquid; mix mixture C, green-lipped mussel powder, gum arabic liquid and composite bacterial agent evenly and granulate them to obtain a finished feed additive.

8. The method for preparing a feed additive for improving starch utilization of California sea bass according to claim 7, characterized in that: In step S1, the amount of deionized water added is 20-30 times the total mass of stevia, sea buckthorn fruit, Jerusalem artichoke, pumpkin seeds and mulberry leaves; the temperature of the temperature-controlled boiling is 98-100°C, and the time is 1.5-2h; the concentration is concentrated to 1 / 4-1 / 3 of the original volume; the temperature of the temperature-controlled drying is 75-80°C; and the screening is through a 600-800 mesh sieve.

9. The method for preparing a feed additive for improving starch utilization of California sea bass according to claim 7, characterized in that: In step S2, the mass concentration of the gum arabic solution is 3-5%; and the rotation speed of the granulation is 700-800 rpm.

10. A use of a feed additive for improving starch utilization of California bass according to any one of claims 5 to 6, characterized in that: The feed additive is added to the fish feed at 1.5-2% of the total weight of the fish feed.

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