Artificial feed for conch containing natural attractant

Abstract

The invention discloses an artificial feed for fragrant snails containing a natural attractant. The artificial feed for fragrant snails contains chicken meat powder, Methylococcus capsulatus protein powder, Clostridium ethanolate protein powder and Candida utilis powder instead of existing proteins such as shrimp meat powder, soybean meal and fish meal. The artificial feed for fragrant snails is prepared by coordinating Nannochloropsis algae powder, Schizochytrium ruthenicum powder, soybean oil, chitosan oligosaccharide, microcrystalline cellulose, complex vitamins, complex minerals and a natural attractant prepared by mixing a protein hydrolysate of river mussels and a carbon dioxide supercritical extraction product of Ruditapes philippinarum. The artificial feed for fragrant snails can significantly improve the feeding behavior of fragrant snails and increase the food intake of fragrant snail larvae, promote the rapid growth of the conches in a relatively short period of time, and effectively solve the problems of the palatability of feed for fragrant snail larvae and the slow growth of artificial feed. More importantly, the artificial feed for fragrant snails can significantly improve the quality of conch meat, save breeding costs, reduce water pollution and improve breeding efficiency.

Description

Technical Field

[0001] The invention belongs to the field of feed, and in particular relates to an artificial feed for conch containing a natural attractant. Background Art

[0002] Conch ( Naptunea cumingi crosse The snail, belonging to the class Gastropoda, subclass Prosobranchia, order Stenoglossidae, family Conchoidea, is a large, carnivorous snail native to temperate marine waters. Its delicious, nutritious meat is highly valued and highly sought after. Traditionally, conchs were primarily caught in the wild, but with increasing catches, natural stocks have been declining. In recent years, to alleviate fishing pressure and meet market demand, artificial breeding and aquaculture techniques have emerged.

[0003] Currently, the artificial breeding and seedling cultivation technology for fragrant snails is relatively stable, and most production processes use small fish as bait. Juvenile snails fed small fish grow faster and the bait is readily available, but there are several drawbacks: Water quality is severely deteriorating, requiring their use only in natural waters; small fish are prone to harboring pathogens, leading to infection and death among juvenile snails; and there is a significant waste of fishery resources. To address the issues associated with feeding small fish, there have been reports on artificial feeds for fragrant snails, such as the Chinese patent publication number CN 102550846 A, titled "A Compound Feed for Fragrant Snails Containing Ginkgo Powder." The feed is formulated with ginkgo powder, shrimp meal, soybean meal, seaweed meal, fish meal, multivitamins, starch, fish oil, yeast, minerals, calcium dihydrogen phosphate, choline, and an attractant in a suitable ratio. However, feed utilization is low, resulting in slow growth of fragrant snails. Summary of the Invention

[0004] The present invention aims to solve the above-mentioned technical problems existing in the prior art and provides an artificial feed for conch containing a natural attractant.

[0005] The technical solution of the present invention is: an artificial compound feed for snails containing natural attractants, wherein the components used and the mass percentages are as follows: 25-50% chicken meal, 10-40% capsular methylcoccus protein powder, 10-25% ethanolic clostridium protein powder, 5-15% utilis yeast powder, 1-10% Nannochloropsis algae powder, 1-10% Schizochytrium algae powder, 2-8% soybean oil, 0.5-2% chitosan oligosaccharide, 0.5-2% microcrystalline cellulose, 0.5-2% complex vitamins, 0.5-2% complex minerals, and 0.05-0.2% natural attractants, wherein the natural attractant is prepared by mixing a hydrolyzate of river mussels and a supercritical carbon dioxide extraction product of Manila clams in a mass ratio of 1-10:0.5-5.

[0006] The river clam protein hydrolysate is prepared according to the following steps: adding water to river clam meat at a volume ratio of 1:3, homogenizing with a high-speed tissue homogenizer, then adding a mixed protease at a mass ratio of 2.0%, performing enzymatic hydrolysis at 50°C and pH 7.0 for 4.5 hours, heating to 90°C and inactivating the enzyme for 20 minutes, obtaining an enzymatic hydrolysate, centrifuging at 4500 rpm for 15 minutes, and spray drying to produce powder, wherein the mixed protease is prepared by mixing flavor protease with an enzyme activity of 180,000 U / g and trypsin with an enzyme activity of 190,000 U / g at a mass ratio of 1:1;

[0007] The Manila clam carbon dioxide supercritical extraction product is prepared by the following steps: desalting Manila clam meat with clean water, low-temperature drying and then powdering, adding anhydrous ethanol in a mass ratio of 1:3, and then supercritically extracting with carbon dioxide for 2 hours at an extraction pressure of 25 MPa, an extraction temperature of 50°C, and a CO2 flow rate of 25 L / h to precipitate a grease-like product.

[0008] The preferred components and mass percentages are 35% chicken meal, 20% capsular methylococcus protein powder, 15% ethanolic clostridium protein powder, 10.9% utilis powder, 5% Nannochloropsis algae powder, 5% Schizochytrium algae powder, 5% soybean oil, 1% chitosan oligosaccharide, 1% microcrystalline cellulose, 1% complex vitamins, 1% complex minerals, and 0.1% natural attractant. The natural attractant is a mixture of river clam protein hydrolysis products and Manila clam carbon dioxide supercritical extraction products in a mass ratio of 5:2.

[0009] The present invention uses chicken meat powder, Methylococcus capsularis protein powder, Clostridium ethanolate protein powder and Candida utilis powder to replace existing shrimp meat powder, soybean meal and fish meal and other proteins, and cooperates with Nannochloropsis algae powder, Schizochytrium algae powder, soybean oil, chitosan oligosaccharide, microcrystalline cellulose, complex vitamins, complex minerals and a natural attractant prepared by mixing protein hydrolysis products of river mussels and carbon dioxide supercritical extraction products of Manila clams as artificial feed for conchs. The artificial feed for conchs can significantly improve the feeding behavior of conchs and increase the food intake of conch larvae, promote the rapid growth of conchs in a relatively short period of time, and effectively solve the problems of palatability of conch larvae feed and slow growth in artificial feed cultivation. More importantly, the present invention can significantly improve the quality of conch meat, save cultivation costs, reduce water pollution and improve cultivation efficiency. DETAILED DESCRIPTION Example 1

[0010] The artificial feed for snails containing natural attractants of the present invention comprises the following components and mass percentages: 35% chicken meal, 20% capsular methylococcus protein powder, 15% ethanolic clostridium protein powder, 10.9% utilis powder, 5% Nannochloropsis algae powder, 5% Schizochytrium algae powder, 5% soybean oil, 1% chitosan oligosaccharide, 1% microcrystalline cellulose, 1% complex vitamins, 1% complex minerals, and 0.1% natural attractant. The natural attractant is prepared by mixing a hydrolysis product of river mussel protein and a supercritical carbon dioxide extraction product of Ruditapes philippinarum in a mass ratio of 5:2.

[0011] The river clam protein hydrolysate is prepared according to the following steps: adding water to river clam meat at a volume ratio of 1:3, homogenizing with a high-speed tissue homogenizer, then adding a mixed protease at a mass ratio of 2.0%, performing enzymatic hydrolysis at 50°C and pH 7.0 for 4.5 hours, heating to 90°C and inactivating the enzyme for 20 minutes, obtaining an enzymatic hydrolysate, centrifuging at 4500 rpm for 15 minutes, and spray drying to produce powder, wherein the mixed protease is prepared by mixing flavor protease with an enzyme activity of 180,000 U / g and trypsin with an enzyme activity of 190,000 U / g at a mass ratio of 1:1;

[0012] The Manila clam carbon dioxide supercritical extraction product is prepared by the following steps: desalting Manila clam meat with clean water, low-temperature drying and then powdering, adding anhydrous ethanol in a mass ratio of 1:3, and then supercritically extracting with carbon dioxide for 2 hours at an extraction pressure of 25 MPa, an extraction temperature of 50°C, and a CO2 flow rate of 25 L / h to precipitate a grease-like product. Example 2

[0013] The present invention discloses an artificial feed for snails containing a natural attractant, wherein the components used and the mass percentages are as follows: 40% chicken meal, 20% Methylococcus capsularis protein powder, 20% Clostridium ethanolicum protein powder, 5% Candida utilis powder, 1% Nannochloropsis algae powder, 8% Schizochytrium algae powder, 3% soybean oil, 0.5% chitosan oligosaccharide, 0.9% microcrystalline cellulose, 0.9% complex vitamins, 0.5% complex minerals, and 0.2% natural attractant. The natural attractant is prepared by mixing a hydrolysis product of river mussel protein and a supercritical carbon dioxide extraction product of Ruditapes philippinarum in a mass ratio of 1:0.5, and the preparation method is the same as that in Example 1. Example 3

[0014] The present invention discloses an artificial feed for snails containing a natural attractant, wherein the components used and the mass percentages are as follows: 25% chicken meal, 40% Methylococcus capsularis protein powder, 10% Clostridium ethanolicum protein powder, 14% Candida utilis powder, 1% Nannochloropsis algae powder, 1% Schizochytrium philippinarum powder, 4% soybean oil, 2% chitosan oligosaccharide, 0.5% microcrystalline cellulose, 0.5% complex vitamins, 1.95% complex minerals, and 0.05% natural attractant. The natural attractant is prepared by mixing a hydrolysis product of river mussel protein and a supercritical carbon dioxide extraction product of Ruditapes philippinarum in a mass ratio of 1:2, and the preparation method is the same as that in Example 1.

[0015] All raw materials in Examples 1-3 were purchased from outside, and the sources of some of the raw materials are shown in the following table:

[0016]

[0017] test:

[0018] 600 juvenile snails (average weight 0.5 g / piece) were selected and divided into 4 experimental groups, with 3 replicates in each experimental group. Culture conditions: water temperature 10-13°C, continuous aeration, and a culture density of 1000 snails / m 2 , the daily water volume is 1 / 3, and the feed is given after the water is changed every afternoon. The feed amount is 6% of the snail body weight (with a little leftover bait). The breeding cycle is 30 days. The specific grouping and feeding are as follows:

[0019] Experimental Group I: The fish were fed with the feed described in Example 1 of "A feed for snails containing ginkgo powder" in Chinese Patent Publication No. CN 102550846 A, wherein the attractant was betaine;

[0020] Experimental Group II: The mice were fed a feed that did not contain any natural attractants and contained 35.1% chicken meal by weight, which was the same as that in Example 1 of the present invention.

[0021] Experimental Group III: The animals were fed the same feed as in Example 1 of the present invention, except that the natural attractant was replaced with betaine;

[0022] Experimental group IV: the rats were fed with the feed of Example 1 of the present invention.

[0023] The measurement indicators are as follows:

[0024] 1. Weight gain rate: Calculation formula: (final weight - initial weight) / initial weight × 100%;

[0025] 2. Feed conversion rate, calculated as: body weight gain / feed intake × 100%;

[0026] 3. Amino acid content in muscle, calculated by the formula: total amino acid content of sample / sample weight × 100%;

[0027] 4. Essential amino acid content in muscle, calculated as: total essential amino acid content of sample / total sample amount × 100%;

[0028] 5. Relative content of polyunsaturated fatty acids in muscle, calculated as: total polyunsaturated fatty acids in the sample / total fatty acid content in the sample × 100%;

[0029] 6. The relative content of DHA + EPA in muscle is calculated as follows: total amount of (DHA + EPA) in the sample / total fatty acid content of the sample × 100%.

[0030] The results are as follows:

[0031]

[0032] Under the same experimental conditions, after the 30-day breeding experiment, the average final body weights of the experimental groups were 0.78g, 0.82g, 0.95g and 1.02g, respectively; the weight gain rates were 56.0%, 64.0%, 80.0% and 104.0%, respectively. The weight gain rate of experimental group IV was significantly higher than that of experimental groups I and II ( P <0.05); the feed conversion rates were 35.7%, 40.0%, 45.5% and 50.0% respectively; the amino acid contents of soft tissues of juvenile snails were 47.12%, 50.16%, 54.68% and 59.72% respectively, and the experimental groups III and IV were significantly higher than those of the experimental group I ( P <0.05); the essential amino acid content increased in sequence. Compared with the experimental groups Ⅰ, Ⅱ and Ⅲ, the essential amino acid content of the experimental group Ⅳ increased by 6.88%, 3.10% and 1.32%, and the experimental groups Ⅱ, Ⅲ and Ⅳ were significantly higher than those of the experimental group Ⅰ ( P <0.05); the relative contents of polyunsaturated fatty acids (PUFAs) were 17.76%, 20.29%, 32.81% and 34.38%, respectively. Among them, the contents of test groups Ⅲ and Ⅳ were significantly higher than those of test groups Ⅰ and Ⅱ ( P <0.05); the relative total amount of DHA+EPA increased from 10.62% in experimental group I to 26.54% in experimental group IV, and the experimental group IV was significantly higher than the first three groups ( P <0.05).

[0033] in conclusion:

[0034] The artificial feed for snails containing natural attractants of the present invention is significantly better than other control groups in terms of weight gain rate, feed conversion efficiency, and meat nutritional components; in addition, after using the embodiments of the present invention, the water quality of the aquaculture water is significantly improved.

Claims

1. An artificial feed for snails containing natural attractants, characterized in that The components used and their mass percentages are as follows: 35% chicken meal, 20% Methylococcus capsulatus protein powder, 15% ethanolic Clostridium protein powder, 10.9% Candida utilis powder, 5% Nannochloropsis algae powder, 5% Schizochytrium algae powder, 5% soybean oil, 1% chitosan oligosaccharide, 1% microcrystalline cellulose, 1% complex vitamins, 1% complex minerals, and 0.1% natural attractant, wherein the natural attractant is prepared by mixing a hydrolyzate of river mussel protein and a supercritical carbon dioxide extraction product of Manila clam in a mass ratio of 5:

2. The river clam protein hydrolysate is prepared according to the following steps: adding water to river clam meat at a volume ratio of 1:3, homogenizing with a high-speed tissue homogenizer, then adding a mixed protease at a mass ratio of 2.0%, performing enzymatic hydrolysis at 50°C and pH 7.0 for 4.5 hours, heating to 90°C and inactivating the enzyme for 20 minutes, obtaining an enzymatic hydrolysate, centrifuging at 4500 rpm for 15 minutes, and spray drying to produce powder, wherein the mixed protease is prepared by mixing flavor protease with an enzyme activity of 180,000 U / g and trypsin with an enzyme activity of 190,000 U / g at a mass ratio of 1:1; The Manila clam carbon dioxide supercritical extraction product is prepared by the following steps: desalting Manila clam meat with clean water, low-temperature drying and then powdering, adding anhydrous ethanol in a mass ratio of 1:3, and then supercritically extracting with carbon dioxide for 2 hours at an extraction pressure of 25 MPa, an extraction temperature of 50°C, and a CO2 flow rate of 25 L / h to precipitate a grease-like product.

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