A tidal flat shellfish feed additive and its preparation method and application

Abstract

The present invention provides a tidal flat shellfish feed additive, which is prepared from a core material raw material and a wall material raw material; the core material raw material includes the following components by mass ratio: 1.5-2.0 parts of glycine, 1.5-2.0 parts of alanine, 0.5-1 parts of dried sea mud, 60-65 parts of soybean oil, 0.5-1 parts of Tween 80, and 30-35 parts of water; the wall material raw material includes the following components by mass ratio: 1-2 parts of gum arabic, 1-2 parts of gelatin, and 95-100 parts of water. The present invention also includes the prepared tidal flat shellfish feed additive and its application. A tidal flat shellfish feed additive and preparation method of the present invention can effectively reduce the shell cracking rate, and has high practicality and commercial promotion value.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, and in particular to a tidal flat shellfish feed additive and a preparation method and application thereof. Background Art

[0002] The output of bivalve aquaculture accounts for more than 70% of the output of marine aquaculture in my country, of which tidal flat shellfish such as clams, cockles and razor clams account for about 55% of the aquacultured shellfish. At present, more than 90% of the seedlings of aquacultured tidal flat shellfish are obtained by factory-based cement pond cultivation. Under the conditions of cement pond cultivation, the feed for juvenile shellfish depends on artificial bait algae with limited diversity, which is nutritionally unbalanced, especially lacking in nutrients for the formation and development of juvenile shellfish, resulting in poor resistance of juvenile shellfish to environmental stress. When environmental conditions fluctuate, the shellfish are prone to rupture and cause losses. For example, when the weather is continuous and rainy and the salinity of seawater decreases, a large number of clams and shellfish rupture and die. Therefore, there is an urgent need for a special feed additive to provide juvenile shellfish with the nutrients needed for shell development.

[0003] At present, there is still a blank in the technology of feed additives for tidal shellfish, not to mention feed additives specifically for shell development. The current feed additive technology and commercial products for aquatic animals such as fish, shrimp, and crab are obviously not suitable for tidal shellfish. First, the calcification of shells is different from the calcification of vertebrate bones and the formation mechanism of crustacean shells, and the nutritional requirements are also different; second, tidal shellfish are filter feeders, which is completely different from the feeding method of fish, shrimp, and crabs. In addition, the special nutritional needs of tidal shellfish shell development are not taken into account in the existing "shellfish feed" patented technologies. Therefore, it is particularly important to develop feed additives that can prevent shell rupture and are green and safe.

[0004] Beach shellfish are invertebrates with soft bodies consisting of a head, foot, visceral mass and mantle. The epithelial cells in the mantle can secrete calcium to form a hard shell to support and protect its soft tissues. Generally speaking, the shells of beach shellfish are composed of about 95 parts by mass of calcium carbonate and 1 to 5 parts of organic matrix. The organic matrix mainly includes chitin and protein. The low expression of framework proteins in the organic matrix in their shells and the inability to form calcium carbonate crystals are an important reason for the shell rupture. Glycine (Glycine, abbreviated as Gly), also known as aminoacetic acid, is a non-essential amino acid. Glycine is an amino acid with a simple chemical structure, but it is very important for the formation of structural proteins such as collagen and elastin. Glycine is a constituent amino acid of the endogenous antioxidant reduced glutathione. It is often supplemented exogenously when the body is under severe stress and is sometimes called a semi-essential amino acid. Alanine (Ala) is the basic unit of protein and the most common amino acid. It is also one of the 21 amino acids that make up human protein. There are two isomers of α-alanine and β-alanine. In the framework protein MSI60 involved in the formation of calcium carbonate crystals, the content of Gly and Ala is the highest. MSI60 fills the space of different shell layers of shells with hydrated gel-like substances (Suzuki Mand Nagasawa H. Mollusk shell structures and their formation mechanism [J]. Canadian Journal of Zoology, 2013, 91 (6): 349-366.). These two amino acids are often used as additives to promote the growth of farmed animals. At present, there are no relevant patents and literature reports on the application of the two amino acids in tidal shellfish.

[0005] Mudflat shellfish grow on mud-rich mudflats. Studies have found that the intake of sea mud is beneficial to the growth and development of mollusks (Liu Y, Dong S, Tian X, et al. Effects of dietary sea mud and yellow soil ongrowth and energy budget of the sea cucumber Apostichopus japonicus (Selenka) [J]. Aquaculture, 2009, 286 (3-4): 266-270.). Sea mud contains many mineral elements and unknown nutritional active substances required for shell growth, which can provide nutrition for the shell formation of mudflat shellfish. At present, there are no relevant patents or literature reports on the application of sea mud on mudflat shellfish. Summary of the invention

[0006] One of the technical problems to be solved by the present invention is to provide a tidal flat shellfish feed additive to fill the technical gap in this field and solve the problem of high shell cracking rate of tidal flat shellfish.

[0007] In order to solve the above problems, the present invention provides a tidal flat shellfish feed additive, wherein the feed additive is prepared from a core material raw material and a wall material raw material;

[0008] The core material raw materials include the following components by weight ratio: 1.5-2.0 parts of glycine, 1.5-2.0 parts of alanine, 0.5-1 parts of sun-dried sea mud, 60-65 parts of soybean oil, 0.5-1 parts of Tween 80, and 30-35 parts of water;

[0009] The wall material raw materials include the following components in terms of mass ratio: 1-2 parts of gum arabic, 1-2 parts of gelatin, and 95-100 parts of water.

[0010] The invention discloses a tidal flat shellfish feed additive, which provides a method for producing the tidal flat shellfish feed additive, can effectively protect and treat juvenile tidal flat shellfish, and is of great significance for preventing and controlling shell breakage.

[0011] As a preferred solution, the core material raw materials include the following components by mass ratio: 1.6 parts of glycine, 1.6 parts of alanine, 0.6 parts of sun-dried sea mud, 63.7 parts of soybean oil, 0.8 parts of Tween 80, and 31.7 parts of water.

[0012] As a preferred solution, the wall material raw materials include the following components in terms of mass ratio: 1 part of gum arabic, 1 part of gelatin, and 98 parts of water.

[0013] As a preferred solution, the mass ratio of the core material raw material to the wall material raw material is 1:(2-3).

[0014] One of the technical problems to be solved by the present invention is to provide a method for preparing the above-mentioned tidal flat shellfish feed additive to fill the technical gap in this field.

[0015] In order to solve the above problems, the present invention provides a method for preparing a tidal flat shellfish feed additive, comprising the following steps:

[0016] S1: mixing the core material raw materials according to a ratio to obtain a core material solution; mixing the wall material raw materials according to a ratio to obtain a wall material solution;

[0017] S2: mixing the core material solution obtained in step S1 with the wall material solution in a mass ratio of 1:2.5 to prepare a mixed solution;

[0018] S3: adjusting the pH value of the mixed solution obtained in step S2, stirring and preparing microcapsules by spray drying, wherein the microcapsules are feed additives for tidal flat shellfish.

[0019] As a preferred solution, in the step S1, the dried sea mud is also prepared before the core material raw materials are mixed according to the ratio, including: taking the sea mud and adding boiling water and stirring, filtering through a sieve and collecting the filtrate, exposing the filtrate to the sun until it is in blocks, and obtaining the dried sea mud.

[0020] As a preferred solution, the sieve is a 1000 mesh sieve.

[0021] As a preferred solution, in step S3, the pH value of the mixed solution is 4, and the adjustment method is to add 10 parts of acetic acid solution to the mixed solution.

[0022] As a preferred solution, in step S3, the stirring time is greater than 15 minutes, and the conditions of the spray drying method are: inlet air temperature 140-170°C, and outlet air temperature 75-90°C.

[0023] Another technical problem to be solved by the present invention is to provide an application of the above-mentioned tidal flat shellfish feed additive to solve the problem of high shell cracking rate of tidal flat shellfish.

[0024] In order to solve the above problems, the present invention provides an application of a tidal flat shellfish feed additive, which includes applying the tidal flat shellfish feed additive to tidal flat shellfish to reduce the shell cracking rate of the tidal flat shellfish.

[0025] Compared with the existing technical solutions, the present invention has the following advantages:

[0026] The preparation method of a tidal flat shellfish feed additive of the present invention comprises the following steps: first preparing two amino acids into an oil-water mixture, and then spray-drying the mixture to form microcapsule particles, thereby preventing the two amino acids from being directly dissolved in water, so that the two amino acids can be directly ingested by tidal flat shellfish, and also preventing water quality deterioration, thereby reducing water pollution.

[0027] The preparation method of the tidal flat shellfish feed additive of the present invention has low raw material cost, simple operation, can realize large-scale production, mild conditions in the whole production process, no intake of toxic substances, and can effectively alleviate shell rupture. At the same time, the production process is simple, the procedure is stable, easy to control, and the success rate is high, which is suitable for enterprises and breeders. DETAILED DESCRIPTION

[0028] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0029] The present invention provides a tidal flat shellfish feed additive, wherein the feed additive is prepared from a core material raw material and a wall material raw material;

[0030] The core material raw materials include the following components by weight ratio: 1.5-2.0 parts of glycine, 1.5-2.0 parts of alanine, 0.5-1 parts of sun-dried sea mud, 60-65 parts of soybean oil, 0.5-1 parts of Tween 80, and 30-35 parts of water;

[0031] The wall material raw materials include the following components in terms of mass ratio: 1-2 parts of gum arabic, 1-2 parts of gelatin, and 95-100 parts of water.

[0032] The invention discloses a tidal flat shellfish feed additive, which provides a method for producing the tidal flat shellfish feed additive, can effectively protect and treat juvenile tidal flat shellfish, and is of great significance for preventing and controlling shell breakage.

[0033] Preferably, the core material raw materials include the following components by mass ratio: 1.6 parts of glycine, 1.6 parts of alanine, 0.6 parts of sun-dried sea mud, 63.7 parts of soybean oil, 0.8 parts of Tween 80, and 31.7 parts of water.

[0034] Preferably, the wall material raw materials include the following components in terms of mass ratio: 1 part of gum arabic, 1 part of gelatin, and 98 parts of water.

[0035] Preferably, the mass ratio of the core material raw material to the wall material raw material is 1:(2-3).

[0036] The present invention provides a method for preparing a tidal flat shellfish feed additive, comprising the following steps:

[0037] S1: mixing the core material raw materials according to a ratio to obtain a core material solution; mixing the wall material raw materials according to a ratio to obtain a wall material solution;

[0038] S2: mixing the core material solution obtained in step S1 with the wall material solution in a mass ratio of 1:2.5 to prepare a mixed solution;

[0039] S3: adjusting the pH value of the mixed solution obtained in step S2, stirring and preparing microcapsules by spray drying, wherein the microcapsules are feed additives for tidal flat shellfish.

[0040] Preferably, in the step S1, before the core material raw materials are mixed according to the ratio, the step also includes the preparation of sun-dried sea mud, including: adding boiling water to the sea mud and stirring, filtering through a sieve and collecting the filtrate, exposing the filtrate to the sun until it is in blocks, and obtaining the sun-dried sea mud.

[0041] Preferably, the sieve is a 1000 mesh sieve.

[0042] Preferably, in step S3, the pH value of the mixed solution is 4, and the adjustment method is to add 10 parts of acetic acid solution to the mixed solution.

[0043] Preferably, in step S3, the stirring time is greater than 15 minutes, and the conditions of the spray drying method are: inlet air temperature 140-170°C, and outlet air temperature 75-90°C.

[0044] The present invention also provides an application of a tidal flat shellfish feed additive, which includes applying the tidal flat shellfish feed additive to tidal flat shellfish to reduce the shell cracking rate of the tidal flat shellfish.

[0045] Example 1

[0046] This embodiment provides a tidal flat shellfish feed additive, which is composed of a core material and a wall material:

[0047] 16g glycine, 16g alanine, 6g sun-dried sea mud, 637g soybean oil, 8g Tween 80 and 317g water as core material raw materials;

[0048] 25g gelatin, 25g gum arabic and 2450g water were used as wall material raw materials.

[0049] The preparation method of the above-mentioned beach shellfish feed additive (microcapsule):

[0050] The preparation method of the sun-dried sea mud is as follows: take an appropriate amount of sea mud from the living environment of tidal flat shellfish, add 100°C boiling water, stir, filter with a 1000-mesh sieve, collect the precipitate, and then expose the collected sea mud to the sun until it is in blocks, thereby obtaining the sun-dried sea mud.

[0051] S1: Add glycine and alanine into water, mix well, then add dried sea mud and mix well, add into soybean oil, and add Tween 80, homogenize and emulsify to obtain core material solution;

[0052] S2: Mix the core material solution with the gelatin and gum arabic aqueous solution at a ratio of 1:2.5.

[0053] S3: Then adjust the pH value to 4.0 with 10 parts of acetic acid solution, stir evenly for not less than 15 minutes, and spray dry to form microcapsules, with an inlet air temperature of 150°C and an outlet air temperature of 85°C;

[0054] Collect the finished products and store them in a -20℃ refrigerator.

[0055] Feed the juvenile novacula constricta with the microcapsules prepared in this embodiment: 5g juvenile novacula constricta were cultivated in 50L water, 2cm thick sea mud was laid on the bottom, water was changed every day, and sea mud was changed once a week. A sufficient amount of mixed microalgae (golden algae: horn algae = 1:1) was added at about 08:00 and 20:00 every day, and the algae cell density in the water body reached 100-120 / μL after each feeding. Microcapsules were fed at the same time as the mixed microalgae, 0.2g was fed per 50L water body, and 3 parallel groups were set. During the cultivation period, the water temperature was 22-25°C, the salinity was 12‰, and the dissolved oxygen was maintained at 6mg / L. The shell cracking rate after one month is shown in Table 1, and the juvenile novacula constricta was very active and grew normally.

[0056] Example 2

[0057] This embodiment provides a tidal flat shellfish feed additive, which is composed of a core material and a wall material:

[0058] 16g glycine, 16g alanine, 6g sun-dried sea mud, 637g soybean oil, 8g Tween 80 and 317g water as core material raw materials;

[0059] 25g gelatin, 25g gum arabic and 2450g water were used as wall material raw materials.

[0060] The preparation method of the above-mentioned tidal flat shellfish feed additive and sun-dried sea mud is the same as that of Example 1.

[0061] Feed the microcapsules prepared in this embodiment to the young clams of the Philippines: 5g of young clams of the Philippines were cultured in 50L of water, and the water was changed every day. A sufficient amount of mixed microalgae (golden algae: horn algae = 1:1) was added at about 08:00 and 20:00 every day, and the algae cell density of the water body reached 100-120 / μL after each feeding. The microcapsules were fed at the same time as the mixed microalgae, 0.2g per 50L of water, and 3 parallel groups were set. During the culture period, the water temperature was 22-25°C, the salinity was 20‰, and the dissolved oxygen was maintained at 6mg / L. The shell cracking rate after one month is shown in Table 1, which is similar to Example 1. The vitality of young clams of the Philippines is normal and the growth is normal, which is similar to Example 1.

[0062] The following provides two groups of comparative examples for comparison with the two groups of embodiments described above:

[0063] Comparative Example 1

[0064] In this comparative example 1, only mixed microalgae were fed to the juvenile novacula constricta: 5g juvenile novacula constricta were cultured in 50L water, 2cm thick sea mud was laid on the bottom, water was changed every day, and sea mud was changed once a week. Sufficient mixed microalgae (chrysophyte: horn algae = 1:1) were added at about 08:00 and 20:00 every day, and the algae cell density in the water body reached 100-120 / μL after each feeding. Three parallel groups were set. During the culture period, the water temperature was 22-25℃, the salinity was 12‰, and the dissolved oxygen was maintained at 6mg / L. The shell cracking rate after one month is shown in Table 1, which is higher than that in Example 1. The juvenile novacula constricta had normal vitality and normal growth.

[0065] Comparative Example 2

[0066] In this comparative example 2, mixed microalgae were only fed to the young clams of the Philippines: 5g of young clams of the Philippines were cultured in 50L of water, and the water was changed every day. Sufficient mixed microalgae (chrysophyte: horn algae = 1:1) were added at about 08:00 and 20:00 every day, and the algae cell density in the water body reached 100-120 cells / μL after each feeding. Three parallel groups were set. During the culture period, the water temperature was 22-25°C, the salinity was 20‰, and the dissolved oxygen was maintained at 6mg / L. The shell cracking rate after one month is shown in Table 1, which is higher than that in Example 2. The vitality and growth of young clams of the Philippines were normal.

[0067] Table 1: Comparison of the breeding effects of the embodiments and the comparative examples

[0068] Shell crack rate <![CDATA[Shell length growth rate (10 -2 μm·d -1 )]]> Example 1 17.4 1.78 Comparative Example 1 30.5 1.76 Example 2 16.7 1.62 Comparative Example 2 31.8 1.59

[0069] If the two amino acids are fed directly, it will affect the water quality. The microorganisms in the water will directly absorb the amino acids, which will increase the number of microorganisms in the water, causing the water quality to deteriorate, and then the symptoms of shell rupture cannot be effectively alleviated, and finally accelerate the death of tidal flat shellfish. The two amino acids are first made into an oil-water mixture, and then spray-dried to form microcapsule particles, which prevents the two amino acids from dissolving directly in water, so that the two amino acids can be directly ingested by tidal flat shellfish, and at the same time, it also avoids water quality deterioration.

[0070] Through the above comparison, it can be found that during the cultivation of juvenile shellfish, the daily water change volume must be guaranteed to be no less than 50 portions. When feeding the microcapsules, the dissolved microcapsule solution should be filtered with an 800-mesh sieve, which can increase the feeding rate of the juvenile shellfish. In addition, the shell cracking rate of Examples 1 and 2 of the technical solution of the present invention is completely lower than that of the comparative example. This further confirms that the tidal flat shellfish feed additive and preparation method of the present invention can effectively reduce the shell cracking rate and have high practicality and commercial promotion value.

[0071] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A method for preparing a tidal flat shellfish feed additive, characterized in that: The following steps are involved: S1: mixing the core material raw materials according to a ratio to obtain a core material solution; mixing the wall material raw materials according to a ratio to obtain a wall material solution; S2: mixing the core material solution obtained in step S1 with the wall material solution in a mass ratio of 1:2.5 to prepare a mixed solution; S3: adjusting the pH value of the mixed solution obtained in step S2, stirring and then preparing microcapsules by spray drying, wherein the microcapsules are feed additives for tidal flat shellfish; The feed additive is prepared from core material raw materials and wall material raw materials; The core material raw materials include the following components by weight ratio: 1.5-2.0 parts of glycine, 1.5-2.0 parts of alanine, 0.5-1 parts of sun-dried sea mud, 60-65 parts of soybean oil, 0.5-1 parts of Tween 80, and 30-35 parts of water; The wall material raw materials include the following components in terms of mass ratio: 1-2 parts of gum arabic, 1-2 parts of gelatin, and 95-100 parts of water.

2. The method for preparing the tidal flat shellfish feed additive according to claim 1, characterized in that: The core material raw materials include the following components by weight: 1.6 parts of glycine, 1.6 parts of alanine, 0.6 parts of sun-dried sea mud, 63.7 parts of soybean oil, 0.8 parts of Tween 80, and 31.7 parts of water.

3. The method for preparing the tidal flat shellfish feed additive according to claim 1, characterized in that: The wall material raw materials include the following components by weight ratio: 1 part of gum arabic, 1 part of gelatin, and 98 parts of water.

4. The method for preparing the tidal flat shellfish feed additive according to claim 1, characterized in that: In the step S1, before the core material raw materials are mixed according to the ratio, the step also includes the preparation of sun-dried sea mud, including: adding boiling water to the sea mud and stirring, filtering through a sieve and collecting the filtrate, exposing the filtrate to the sun until it is in block form, and obtaining the sun-dried sea mud.

5. The method for preparing the tidal flat shellfish feed additive according to claim 4, characterized in that: The sieve is a 1000 mesh sieve.

6. The method for preparing the tidal flat shellfish feed additive according to claim 1, characterized in that: In step S3, the pH value of the mixed solution is 4, and the adjustment method is to add 10 parts of acetic acid solution to the mixed solution.

7. The method for preparing the tidal flat shellfish feed additive according to claim 1, characterized in that: In step S3, the stirring time is greater than 15 minutes, and the conditions of the spray drying method are: inlet air temperature is 140-170°C, and outlet air temperature is 75-90°C.