Juvenile seriola dumerili artificial compound feed for replacing frozen fishes, and use thereof

Abstract

The present invention relates to the field of aquatic animal feed, and provides a juvenile Seriola dumerili artificial compound feed for replacing frozen fishes, and a use thereof. In the present invention, super steam-dried fish meal, chicken meal and whole shrimp meal are used as high-quality animal protein sources, dehulled soybean meal and vital wheat gluten are used as high-quality plant protein sources, fish oil and soybean oil in a relatively high proportion are adopted, and high gluten flour, fermented soybean meal, monocalcium phosphate, vitamin blend, mineral blend, phospholipid, choline, L-ascorbate-2-monophosphate, taurine, lysine and methionine are added. The juvenile Seriola dumerili artificial compound feed for replacing frozen fishes of the present invention involves rich formula, is rich in protein, fat, amino acid, various vitamins and other key nutrient substances required by the development of juvenile Seriola dumerili, not only can provide sufficient nutrition for juvenile Seriola dumerili and promote the healthy growth of juvenile Seriola dumerili, but also improve the nutritional value and flavor of juvenile Seriola dumerili, and has the advantages of low production cost, high feed utilization rate, easy storage, convenient feeding and the like.

Description

A formulated feed for high-body yellowtail juveniles as an alternative to frozen fish and its application Technical Field

[0001] This invention relates to the field of aquatic animal feed, and more particularly to a high-body amberjack juvenile artificial feed as an alternative to chilled fish and its application. Background Technology

[0002] The high-bodied amberjack (Seriola dumerili) belongs to the order Perciformes, family Carangidae, and genus Seriola. It has a very wide distribution, mainly in tropical and subtropical seas, including the East China Sea and South China Sea. High-bodied amberjacks are characterized by rapid growth and strong environmental adaptability. In artificial cage culture, they can reach a weight of 1.0-1.5 kg in the first year, resulting in significant economic benefits. They are currently a major export fish in southern marine cage aquaculture. High-bodied amberjacks are rich in high-quality protein, essential amino acids, and fatty acids, making them highly sought after by consumers and possessing great potential in the global aquaculture market. They have now become a new species for the development of my country's deep-sea aquaculture industry.

[0003] Currently, in the domestic amberjack aquaculture process, frozen miscellaneous fish are used as feed. However, frozen miscellaneous fish have problems such as unbalanced nutrition, easy introduction of pathogens, high feed conversion ratio and feeding costs, and increased environmental pollution and disease, which seriously restrict the sustainable and healthy development of amberjack aquaculture. Artificial compound feed, on the other hand, has advantages such as low feed conversion ratio, comprehensive nutrition, high safety, low feeding costs, and less pollution to the aquatic environment, making it an environmentally friendly green aquaculture method. Therefore, strengthening feed technology research and development to create a high-efficiency compound feed that can replace frozen miscellaneous fish can provide an internal driving force for the sustainable development of amberjack aquaculture. Therefore, this invention, through aquaculture experiments using compound feed instead of frozen fish, determined the nutritional composition and muscle quality of juvenile amberjack, thereby developing a high-efficiency amberjack feed formula and producing it into a commercial feed for the aquaculture of juvenile amberjack.

[0004] Summary of the Invention

[0005] In view of this, the present invention provides an artificial formulated feed for high-body amberjack juveniles as an alternative to fresh fish and its application. This feed is rich in key nutrients required for the development of high-body amberjack juveniles, such as protein, fat, amino acids, and various vitamins. It not only enhances the nutritional value and flavor of the amberjack but also has advantages such as low production cost, high feed utilization rate, easy storage, and convenient feeding, making it easier to use in aquaculture. This feed can be applied to the artificial breeding of high-body amberjack juveniles, promoting large-scale amberjack farming.

[0006] This invention is achieved using the following technical solution:

[0007] A high-body amberjack juvenile artificial feed to replace chilled fish comprises the following components by weight: 40-47 parts super steam fish meal, 5-10 parts high-gluten flour, 5-10 parts peeled soybean meal, 5-7 parts chicken meal, 5-7 parts wheat gluten, 5-10 parts whole shrimp meal, 5-7 parts fermented soybean meal, 3-5 parts soybean oil, 3-5 parts fish oil, 1.0-1.5 parts calcium dihydrogen phosphate, 0.4-1.0 parts vitamin mixture, 0.5-1.0 parts mineral mixture, 1-2 parts phospholipids, 0.2 parts choline, 0.1 parts vitamin C phosphate (VC ester), 0.1 parts taurine, 0.1 parts lysine, and 0.1 parts methionine.

[0008] Preferably, the crude protein (CP) content of the dehulled soybean meal is 46%.

[0009] Preferably, each 100g of the vitamin mixture comprises the following components: Vitamin A 4 million IU-8 million IU, Vitamin E 2g-2.4g, Vitamin D3 3 million IU-3.8 million IU, Vitamin K 0.01g-0.08g, Vitamin C 3.3g-3.7g, Vitamin B1 0.5g-1g, Vitamin B2 0.6g-1g, Vitamin B3 4.6g-5g, Vitamin B5 1g-1.5g, Vitamin B6 0.3g-0.6g, Vitamin B9 0.4g-0.7g, Vitamin B... 12 0.03g-0.07g, Biotin 0.02g-0.05g, Inositol 17g-20g, Cellulose 50g-70g.

[0010] Preferably, each 100g mineral mixture includes the following components: potassium 2.5g-3g, iron 5g-15g, sodium 2g-5g, cobalt 0.1g-0.4g, magnesium 5g-8g, iodine 3g-6g, zinc 5g-15g, selenium 0.2g-0.5g, manganese 2g-8g, and copper 2g-5g.

[0011] Preferably, the phospholipid has a purity of 55%.

[0012] Preferably, the purity of the choline is 50%.

[0013] The functions of each component in the artificial formulated feed for high-body yellowtail juveniles that replaces chilled fish in this invention are as follows:

[0014] Super steam fishmeal has a protein content of over 55%, containing high-quality protein and fat. It is not only an excellent animal protein feed that balances protein and amino acids, but also an optimal feed that balances minerals and trace elements. It is produced using a two-stage indirect hot air drying process, which effectively maintains the high digestibility and quality of the fishmeal, making it an important source of animal protein.

[0015] High-gluten flour, as an energy-enhancing ingredient, can adjust the proportion of carbohydrates in feed and acts as a binder when making sinking pellet feed.

[0016] Soybean meal, as an important plant protein source of energy and amino acids for animals, has the same value as animal protein sources. Peeled soybean meal, a product of a new soybean peeling and extraction process, has a higher nutrient digestibility than ordinary soybean meal, providing higher protein and energy. Fermented soybean meal, produced through specific processes and technologies, increases the solubility of soybean protein while reducing its molecular weight, making it more easily digestible and absorbable by animals. Fermented soybean meal also has a certain aroma and umami flavor, which enhances its palatability. Furthermore, some polysaccharide molecules and flatulence factors in soybean meal are broken down during fermentation, which not only aids animal digestion but also reduces anti-nutritional factors in the plant.

[0017] Chicken meal is a high-quality protein source with a balanced amino acid composition, high digestibility and easy absorption, low content of anti-nutritional factors, and good conversion effect, which can reduce feed costs.

[0018] Gluten is a high-quality protein source with high digestibility and high levels of glutamine. It provides nutrition to animals while improving gut health and regulating immunity. It also has coagulant properties and can be used as a pellet binder in feed.

[0019] Shrimp meal is a high-quality protein source that can improve the growth performance, immunity, antioxidant capacity, and reproductive performance of aquatic animals, as well as improve the quality of animal muscle.

[0020] Soybean oil is a high-quality, high-energy feed, with twice the energy value of carbohydrates and proteins. It provides animals with essential unsaturated fatty acids. Soybean oil significantly improves feed palatability, increases feed intake, prolongs the residence time of feed in the digestive tract, and facilitates the absorption and utilization of nutrients. The lubricating properties of soybean oil help improve the appearance of feed, and appropriate amounts of soybean oil can reduce heat stress in animals caused by high temperatures.

[0021] Fish oil is obtained from fish and their waste through steaming, pressing, and refining, and is a byproduct of fishmeal processing. Fish oil is rich in vitamins A and D, as well as n-3 polyunsaturated fatty acids such as EPA and DHA. It can add aroma to feed, improve palatability, and has an excellent appetite-stimulating effect. It is a high-grade oil that combines nutrition, palatability, and functionality.

[0022] Calcium dihydrogen phosphate primarily provides aquatic animals with mineral nutrients such as phosphorus and calcium. It not only improves the bioavailability of phosphorus and calcium in feed but also enhances the physical properties and palatability of the feed. Simultaneously, calcium dihydrogen phosphate promotes the growth and development of aquatic animals, strengthens their constitution, and improves their disease resistance, thereby increasing the growth rate and overall survival rate of farmed aquatic animals.

[0023] The vitamin mixture primarily provides fish with various vitamins. Vitamins participate in the regulation of metabolism, maintain the balance of system functions, enhance the fish's disease resistance, and ensure normal growth.

[0024] The mineral element mixture mainly provides fish with various essential trace elements. Trace elements participate in various life activities of the body and are indispensable factors for ensuring the health, growth, reproduction and production of fish.

[0025] Phospholipids can promote the healthy development of the brain, nervous tissue, internal organs, and bone marrow in fish, conserve methionine consumption, improve feed quality, and promote reproductive function and normal development in animals. Furthermore, phospholipids can provide linolenic acid and linolenic acid, which fish cannot synthesize themselves.

[0026] Choline can promote the resynthesis of amino acids in animals, improve the fish's immunity and nutrient absorption capacity, thereby reducing the chance of disease.

[0027] Vitamin C phosphate esters (VC esters) are produced through highly efficient catalytic phosphorylation. Their phosphate ester form can be converted into free vitamin C in aquatic animals, helping to eliminate free radicals in farmed aquatic animals, improving their antioxidant capacity, and thus enhancing their immunity. At the same time, VC esters are stable under high temperature and pressure, reducing vitamin C loss during feed processing and storage, ensuring sufficient vitamin C supply to the animals, and thereby improving feed utilization.

[0028] Taurine can be synthesized from sulfur amino acids such as cysteine, cystine and methionine in the animal body through a series of enzymatic reactions. It participates in the metabolic regulation of proteins, carbohydrates and lipids, and has the functions of improving antioxidant capacity, hypoxia tolerance, osmotic pressure regulation and immune regulation in fish.

[0029] Lysine and methionine are limiting essential amino acids that aquatic animals cannot synthesize. Supplementing with artificially produced lysine and methionine can meet the needs of aquatic animals, enhance the nutritional value of feed protein, and greatly improve aquaculture results.

[0030] Another objective of this invention is to provide an artificial compound feed for high-body amberjack juveniles as an alternative to fresh fish in improving the nutritional composition of the muscle and enhancing the flavor of the meat.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. This invention uses super steamed fish meal, chicken meal, and whole shrimp meal as high-quality animal protein sources, which not only meet the fish's protein requirements but also improve the fish's antioxidant and immune capabilities, enhance muscle quality, and reduce feed costs. Soybean meal and wheat gluten are used as high-quality plant protein sources, providing the fish with nutrition and high energy. Furthermore, these plant protein sources have low levels of anti-nutritional factors, preventing excessive antigenic substances, improving gut health, and enhancing immunity, thereby promoting the healthy growth of high-body-size amberjack.

[0033] 2. The fermented soybean meal added in this invention has an aromatic aroma and umami flavor, which has a significant palatability and appetite-stimulating effect on fish.

[0034] 3. This invention uses a high proportion of fish oil, which provides fish with vitamins A and D, as well as n-3 essential polyunsaturated fatty acids such as EPA and DHA. This imparts aroma and improves palatability to the feed, increasing fish feed intake. Simultaneously, this invention also uses a high proportion of soybean oil as a high-energy feed, with an energy value 2.25 times that of carbohydrates and proteins, providing fish with a large amount of energy. Soybean oil also contains a large amount of linoleic acid, which plays an important role in the health, development, and immunity of fish.

[0035] 4. This invention adds phospholipids and choline, which can not only promote the synthesis of fatty acids such as linolenic acid and linoleic acid that fish cannot synthesize on their own, but also promote the resynthesis of amino acids in the animal's body, increase the fatty acid and amino acid levels in the muscle, and improve the nutritional value of the muscle.

[0036] 5. This invention includes taurine, which can participate in the enzymatic synthesis of sulfur-containing amino acids such as methionine in the body, promoting amino acid production and thus increasing amino acid content. This invention also includes limiting essential amino acids (lysine and methionine) that cannot be synthesized in fish. These two can supplement the fish's requirement for lysine and methionine, thereby improving the fish's utilization of other essential and non-essential amino acids and increasing the protein content of the fish. Attached Figure Description

[0037] Figure 1 shows the expression levels of muscle growth regulators and collagen-encoding genes in juvenile yellowtail amberjack from Example 1 and Comparative Example 1; * indicates significant differences between groups (P<0.05), and ** indicates extremely significant differences between groups (P<0.01). Detailed Implementation

[0038] The present invention will be further described below with reference to the embodiments.

[0039] Example 1

[0040] A formulated feed for high-body amberjack juveniles, which can replace frozen fish, has the following components in parts by weight:

[0041] 47 parts super steamed fish meal, 10 parts high-gluten flour, 5 parts peeled soybean meal (CP content 46%), 5 parts chicken meal, 5 parts wheat gluten, 10 parts whole shrimp meal, 5 parts fermented soybean meal, 4 parts soybean oil, 4 parts fish oil, 1.5 parts calcium dihydrogen phosphate, 0.4 parts vitamin mixture, 0.5 parts mineral mixture, 2 parts phospholipids (purity 55%), 0.2 parts choline (purity 50%), 0.1 parts vitamin C phosphate (VC ester), 0.1 parts taurine, 0.1 parts lysine, and 0.1 parts methionine.

[0042] The components and their content per 100g of the vitamin mixture are as follows:

[0043] Vitamin A 8 million IU, Vitamin E 2.4g, Vitamin D3 3.8 million IU, Vitamin K 0.08g, Vitamin C 3.7g, Vitamin B1 1g, Vitamin B2 1g, Vitamin B3 5g, Vitamin B5 1-1.5g, Vitamin B6 0.6g, Vitamin B9 0.7g, Vitamin B... 12 0.07 g, Biotin 0.05 g, Inositol 20 g, Cellulose 70 g.

[0044] The composition and content of each component per 100g of the mineral mixture are as follows:

[0045] Potassium 2.5g, Iron 7.5g, Sodium 3g, Cobalt 0.2g, Magnesium 6g, Iodine 5g, Zinc 7.5g, Selenium 0.3g, Manganese 5g, Copper 3g.

[0046] The vitamin mixture and mineral mixture in the above ingredients are recommended, but not limited to, purchased from Guangdong Yuequn Marine Biotechnology Co., Ltd. (Jieyang, Guangdong, China), or other commercially available similar products can be used as substitutes.

[0047] Example 2

[0048] A formulated feed for high-body amberjack juveniles, which can replace frozen fish, has the following components in parts by weight:

[0049] 45 parts super steamed fish meal, 10 parts high-gluten flour, 10 parts peeled soybean meal (CP content 46%), 5 parts chicken meal, 5 parts wheat gluten, 10 parts whole shrimp meal, 5 parts fermented soybean meal, 3 parts soybean oil, 3 parts fish oil, 1.5 parts calcium dihydrogen phosphate, 0.4 parts vitamin mixture, 0.5 parts mineral mixture, 1 part phospholipid (purity 55%), 0.2 parts choline (purity 50%), 0.1 parts vitamin C phosphate (VC ester), 0.1 parts taurine, 0.1 parts lysine, and 0.1 parts methionine.

[0050] The composition and content of the vitamin mixture and mineral mixture in Example 2 are the same as those in Example 1.

[0051] Example 3

[0052] A formulated feed for high-body amberjack juveniles, which can replace frozen fish, has the following components in parts by weight:

[0053] 43 parts super steamed fish meal, 8 parts high-gluten flour, 9 parts peeled soybean meal (CP content 46%), 6 parts chicken meal, 7 parts wheat gluten, 6 parts whole shrimp meal, 6 parts fermented soybean meal, 4 parts soybean oil, 5 parts fish oil, 1.5 parts calcium dihydrogen phosphate, 1 part vitamin mixture, 0.9 parts mineral mixture, 2 parts phospholipids (purity 55%), 0.2 parts choline (purity 50%), 0.1 parts vitamin C phosphate (VC ester), 0.1 parts taurine, 0.1 parts lysine, and 0.1 parts methionine.

[0054] The composition and content of the vitamin mixture and mineral mixture in Example 3 are the same as those in Example 1.

[0055] Example 4

[0056] A formulated feed for high-body amberjack juveniles, which can replace frozen fish, has the following components in parts by weight:

[0057] 40 parts super steamed fish meal, 10 parts high-gluten flour, 10 parts peeled soybean meal (CP content 46%), 7 parts chicken meal, 6 parts wheat gluten, 5 parts whole shrimp meal, 7 parts fermented soybean meal, 5 parts soybean oil, 5 parts fish oil, 1 part calcium dihydrogen phosphate, 0.8 parts vitamin mixture, 0.6 parts mineral mixture, 2 parts phospholipids (purity 55%), 0.2 parts choline (purity 50%), 0.1 parts vitamin C phosphate (VC ester), 0.1 parts taurine, 0.1 parts lysine, and 0.1 parts methionine.

[0058] The composition and content of the vitamin mixture and mineral mixture in Example 4 are the same as those in Example 1.

[0059] Comparative Example 1

[0060] Unlike Examples 1-4, Comparative Example 1 used fresh fish instead of formulated feed.

[0061] High-body amberjack juveniles were cultured for 60 days using the artificial feed from Examples 1-4 (which replaced the fresh fish in Comparative Example 1) and the fresh fish in Comparative Example 1. The specific experimental methods and results are as follows:

[0062] I. Experimental Methods

[0063] 1. Farming of juvenile amberjack

[0064] The experiment was conducted in a 6m×6m×3m net cage. 500 healthy juvenile amberjack of similar weight were selected and divided into five experimental groups of 100 fish each. They were fed with the artificial compound feed for juvenile amberjack that replaced fresh fish in Examples 1-4 and the fresh fish in Comparative Example 1, respectively. The fish stopped feeding as a signal to stop feeding. The fish were raised for 60 days.

[0065] 2. Collection of samples from juvenile amberjack

[0066] After a 60-day rearing experiment, juvenile amberjack were fasted for 24 hours. Thirteen fish were randomly selected from each experimental group's net cages and anesthetized with 100 mg / L ethyl m-aminobenzoate methanesulfonate (MS-222). After anesthesia, the body length and weight of all fish were measured. Three whole fish from each group were used for whole-fish nutrient composition analysis, and ten fish from each group were also selected to measure visceral weight and liver weight, among other indicators, to calculate body composition and feed conversion ratio. Two muscle tissue samples were collected; one sample was placed in an enzyme-free sealed bag for routine nutrient composition and amino acid analysis; the other sample was placed in an RNA polymerase chain. TM After being incubated overnight at 4°C in an RNA stabilization solution in animal tissues, the samples were rapidly transferred to an ultra-low temperature freezer at -80°C for storage, and used to determine the expression levels of growth-related genes.

[0067] Liver body index = W h / W×100,

[0068] Visceral Index = W v / W×100,

[0069] Body fatness = Wt / L 3 ×100,

[0070] Feed conversion ratio = W f / (W t -W o ),

[0071] In the formula, t represents the number of days of feeding (d); W f W represents the total dry weight of feed consumed (g). t W represents the final average weight (g). o W represents the initial average weight (g). v Visceral weight (g); W h Liver weight (g); W is body weight (g); L is body length (cm).

[0072] 3. Determination of nutritional components of whole fish and muscle

[0073] The nutritional composition of whole fish and muscle tissue in the high-body yellowtail juvenile feed group (replacing fresh fish) of Examples 1-4 and the fresh mixed fish group (Comparative Example 1) was tested by Sichuan Weier Testing Technology Co., Ltd. (Chengdu, Sichuan, China). The test indicators for whole fish and muscle samples included conventional nutritional components, hydrolyzed amino acids, and fatty acids. For conventional nutrient components, moisture was determined by drying at 103℃ (GB / T 6435-2014); ash was determined by calcination at 550℃ in a muffle furnace (GB / T 6438-2007); crude protein was determined by the Kjeldahl method (GB / T 6432-2018 7.2); crude fat was determined by Soxhlet extraction (GB / T 6433-2006); crude fiber was determined by filtration (GB / T 6434-2006); calcium was determined by disodium ethylenediaminetetraacetate complexometric titration (GB / T 6436-2018); total phosphorus was determined by spectrophotometry (GB / T 6437-2018); and water-soluble chloride was determined according to the method described in (GB / T 6439-2007).

[0074] 4. Determination of muscle amino acid content

[0075] The determination of muscle amino acid content in the high-body yellowtail juvenile fish artificial feed group (replacing fresh fish) in Examples 1-4 and the fresh mixed fish group (Comparative Example 1) was entrusted to Sichuan Weier Testing Technology Co., Ltd. (Chengdu, Sichuan, China). The composition and content of hydrolyzed amino acids were determined using a Hitachi L-8900 automatic amino acid analyzer (GB 5009.124-2016). Samples were pretreated using oxidative acid hydrolysis before determination.

[0076] The percentage content (%) of various essential amino acids in muscle samples was converted into milligrams of amino acids per gram of nitrogen (mg / g N). The amino acid score (AAS), chemical score (CS), and essential amino acid index (EAAI) of the protein were calculated by comparing the amino acid scoring standard model recommended by the Food and Agriculture Organization of the United Nations / World Health Organization (FAO / WHO) with the amino acid model of whole egg protein.

[0077] AAS = Amino acid content of the protein to be evaluated (mg / gN) / Amino acid content in the FAO scoring model (mg / gN)

[0078] CS = Amino acid content of the protein to be evaluated (mg / gN) / Content of the same amino acid in whole egg protein (mg / gN)

[0079] In the formula, the amino acid content refers to the amount of amino acids in milligrams per gram of nitrogen.

[0080] Amino acid content (mg / g N) = muscle amino acid percentage × 6.25 × 1000 / muscle protein percentage

[0081] EAAI=[(100A / AE)×(100B / BE)×(100C / CE)×…×(100H / HE)] 1 / n

[0082] In the formula, n is the number of essential amino acids being compared, A, B, C, ..., H are the contents of each essential amino acid in the sample (mg / g N), and AE, BE, CE, ..., HE are the contents of the corresponding essential amino acids in whole egg protein (mg / g N).

[0083] 5. Determination of the expression levels of growth-related genes in the muscle of juvenile amberjack.

[0084] Total RNA was extracted from muscle tissue according to the Trizol kit (15596108, Invitrogen, USA). 1 μL of total RNA was analyzed for degradation and contamination using 1.5% agarose gel electrophoresis; another 1 μL of total RNA was analyzed for concentration and quality using a 2000 ultra-micro nucleic acid and protein analyzer (Thermo Scientific, USA). 1 μg of each RNA sample was then processed according to PrimeScript. TM cDNA was synthesized according to the instructions of the RT reagent Kit with gDNA Eraser (Perfect Real Time) kit (TaKaRa, RR047A, Japan) and stored at -20°C for later use.

[0085] The expression levels of growth-related genes in the muscle of tall yellowtail amberjack were detected using qPCR. The reaction was performed in Roche Light. The qPCR was performed on a Roche 96 real-time quantitative PCR instrument (Switzerland). The qPCR was performed according to the instructions of the SYBR Green Real Time PCR MasterMix kit (TOYOBO, QPK-201, Japan). The reaction mixture consisted of 10 μL of SYBR Green Real Time PCR MasterMix, 0.5 μL each of forward and reverse primers, 1 μL of cDNA template, and enzyme-free water to a final volume of 20 μL. The reaction program was: 95℃ for 300 s pre-denaturation; 95℃ for 30 s, 60℃ for 20 s, 72℃ for 20 s (signal collection), 40 cycles; 95℃ for 10 s, 65℃ for 60 s, 97℃ for 1 s; 37℃ for 30 s. The housekeeping gene β-actin was used as an internal reference gene, and the primer sequences were set correctly. 2 -ΔΔCt The method calculates the relative expression levels of growth-related genes in muscle.

[0086] II. Experimental Results

[0087] 1. Growth indicators of high-body amberjack

[0088] The growth indicators of the high-body yellowtail juveniles fed with the artificial compound feed that replaced fresh fish in Examples 1-4 and the fresh mixed fish group in Comparative Example 1 are shown in Table 1.

[0089] Table 1

[0090] Note: ** indicates that the difference between the two groups is extremely significant (P<0.01), and no label indicates that there is no significant difference between the two groups (P>0.05).

[0091] Table 1 shows that the liver-to-body ratio, visceral-to-body ratio, and condition factor of the high-body amberjack juveniles fed the artificial feeds of Examples 1-4 (as a substitute for fresh fish) were not significantly different from those of the controlled example (fresh mixed fish) (P>0.05). However, the feed conversion ratio was significantly lower than that of the fresh mixed fish (P<0.01). This indicates that using the artificial feeds of Examples 1-4 (as a substitute for fresh fish) to raise high-body amberjack juveniles is more cost-effective and has lower farming costs. Based on a comprehensive evaluation of the growth performance of high-body amberjack juveniles in each example, the artificial feed of Example 1 (as a substitute for fresh fish) produced the highest liver-to-body index, visceral-to-body index, and condition factor, and the lowest feed conversion ratio. Therefore, it is considered that the artificial feed of Example 1 (as a substitute for fresh fish) is the most effective.

[0092] 2. Nutritional composition of juvenile amberjack

[0093] The whole fish samples of the high-body yellowtail juvenile fish artificial feed group (which replaced fresh fish in Example 1) and the fresh mixed fish group (Comparative Example 1) were analyzed for their whole fish nutrient composition. The data are shown in Table 2.

[0094] As shown in Table 2, there was no significant difference in the moisture and crude fiber content of the whole fish in the artificial feed group for high-body yellowtail juveniles in Example 1 (replacing fresh fish) and the group of fresh mixed fish in Comparative Example 1 (P>0.05). The crude fat content of the whole fish in the group of fresh mixed fish in Comparative Example 1 was significantly higher than that in the feed group (P<0.01). However, the water-soluble chloride, calcium, crude ash, crude protein, and total phosphorus content of the whole fish in the artificial feed group for high-body yellowtail juveniles in Example 1 (replacing fresh fish) was significantly higher than that in the group of fresh fish (P>0.01). The experiment shows that the high-body yellowtail juveniles raised using the artificial feed for high-body yellowtail juveniles in Example 1 (replacing fresh fish) can improve the overall protein level of the whole fish and provide better nutritional value.

[0095] Table 2 (Wet Weight) g / 100g

[0096] Note: Those marked with ** in the same column indicate extremely significant differences between groups (P<0.01), and those without marking indicate no significant differences between groups (P>0.05).

[0097] 3. Nutritional composition of muscle in juvenile amberjack

[0098] The nutritional composition of muscle samples from high-body yellowtail juveniles fed with artificial feed that replaced fresh fish in Example 1 and Comparative Example 1 (fresh mixed fish) was determined, and the data are shown in Table 3.

[0099] As shown in Table 3, there were no significant differences in the water-soluble chloride, moisture, calcium, crude ash, crude fat, and total phosphorus content of the amberjack muscle between the artificial feed for replacing frozen fish in Example 1 and the frozen mixed fish group in Comparative Example 1 (P>0.05). However, the crude fiber and crude protein content of the muscle of the amberjack group fed with the artificial feed for replacing frozen fish in Example 1 was significantly higher than that of the frozen fish group (P<0.05). The experiment shows that using the artificial feed for replacing frozen fish in Example 1 to raise amberjack can improve the protein nutritional value of the muscle of amberjack. Moreover, the higher crude protein content can improve the hardness, elasticity, and chewiness of the fish meat, enrich the taste of the fish meat, and enhance its edibility.

[0100] Table 3 (Wet Weight) g / 100g

[0101] Note: Those marked with * in the same column indicate significant differences between groups (P<0.05), and those without marking indicate no significant differences between groups (P>0.05).

[0102] 4. Evaluation of amino acid composition and content in the muscle of high-body yellowtail juveniles and the nutritional value of essential amino acids.

[0103] The amino acid composition and content of muscle samples from juvenile amberjacks fed with artificial feed that replaced fresh fish in Example 1 and Comparative Example 1 (fresh mixed fish) were determined. The data are shown in Table 4.

[0104] Table 4 (Wet Weight) g / 100g

[0105] Note: # Essential amino acids, ∑EAA: total essential amino acids, ∑TAA: total amino acids. * indicates a significant difference between groups (P<0.05), ** indicates an extremely significant difference between groups (P<0.01), and no label indicates no significant difference between groups (P>0.05).

[0106] As shown in Table 4, feeding the high-body yellowtail juveniles with the artificial feed from Example 1 (which replaced fresh fish) significantly affected the amino acid content in their muscle. The total content of 16 amino acids, essential amino acids, and flavor amino acids in the muscle of the high-body yellowtail juveniles fed with the artificial feed from Example 1 (which replaced fresh fish) were significantly higher than those in the high-body yellowtail juveniles fed with the fresh fish from Comparative Example 1 (P<0.01). Furthermore, the total essential amino acid / total amino acid (EAA / TAA) ratio in the muscle of the high-body yellowtail juveniles fed with the artificial feed from Example 1 (which replaced fresh fish) and the high-body yellowtail juveniles fed with the fresh fish from Comparative Example 1 were 40.69% and 40.76%, respectively.

[0107] The nutritional value of muscle protein depends primarily on the types and amounts of essential amino acids it contains. Essential amino acids must be obtained directly from food to maintain the body's nitrogen balance and the fish's health. In Example 1 of this invention, the total content of 16 amino acids and the content of essential amino acids in the muscle of high-body amberjack juveniles fed with the artificial formulated feed that replaced fresh fish were significantly higher than those fed with fresh fish in Comparative Example 1, indicating that the formulated feed of this invention can increase the amino acid content in muscle. This is due to the chicken meal, wheat gluten, and whole shrimp meal added to the formulated feed of this invention, which provide high-quality, high-energy animal and plant protein sources for high-body amberjack juveniles, providing abundant amino acids and proteins for digestion and absorption. The limiting essential amino acids (lysine and methionine) added in this invention also contribute to the increase in amino acid content in muscle. Furthermore, the addition of limiting essential amino acids can improve amino acid utilization, promote amino acid resynthesis, and thus promote protein production, thereby increasing the protein content in the muscle of high-body amberjacks. Furthermore, the taurine added in this invention can participate in the enzymatic synthesis of sulfur-containing amino acids such as cysteine ​​and methionine in the body, accelerating the synthesis of sulfur-containing amino acids. The phospholipids added in this invention can conserve methionine consumption and increase methionine content.

[0108] The composition and content of flavor amino acids (glutamic acid, aspartic acid, glycine, and alanine) significantly influence the umami flavor of animal proteins. Higher levels of umami amino acids in muscle result in a higher level of umami flavor. Among flavor amino acids, glutamic acid (Glu) and aspartic acid (Asp) are umami amino acids, with Glu having the strongest influence on umami. In Example 1 of this invention, the high-body amberjack juveniles fed with the artificial compound feed that replaced chilled fish had higher levels of flavor amino acids in their muscle, indicating that the muscle of the amberjack juveniles fed with the artificial compound feed that replaced chilled fish in Example 1 had a higher degree of umami aftertaste and better flavor. This is because the compound feed of this invention contains a higher proportion of fish oil and fermented soybean meal, which, due to their aromatic and umami flavors, not only significantly improve the palatability and feeding effect of fish but also influence the flavor of the muscle. Furthermore, in Example 1 of this invention, the proline (Pro) content in the muscle of high-body yellowtail juveniles fed with artificial formulated feed instead of fresh fish was significantly higher than that in the high-body yellowtail juveniles fed with fresh fish in Comparative Example 1. Pro can work in synergy with vitamin C to improve the firmness of the fish meat and the content of collagen, enhance the antioxidant capacity of the muscle, and improve the freshness and taste of the muscle.

[0109] According to the FAO / WHO ideal protein model, a good quality protein should have an EAA / TAA ratio of around 40%. In Example 1 of this invention, the EAA / TAA ratios in the muscle of high-body amberjack juveniles fed with frozen fish (as a substitute for frozen fish) and in Comparative Example 1 (fed with frozen fish) were 40.69% and 40.76%, respectively, both around 40%. This indicates that the EAA / TAA ratios in both the Example 1 and Comparative Example 1 are appropriate and meet the ideal level of edible protein. Furthermore, there was no significant difference in the EAA / TAA ratios between the Example 1 and Comparative Example 1 feeds, indicating that both feeds and Comparative Example 1 feeds have good protein nutritional value.

[0110] The nutritional value of essential amino acids in the muscle samples of high-body yellowtail juveniles fed with the artificial compound feed that replaced frozen fish in Example 1 and the high-body yellowtail juveniles fed with frozen mixed fish in Comparative Example 1 was evaluated, and the results are shown in Table 5.

[0111] Table 5

[0112] As shown in Table 5, EAAI (Essential Amino Acids) is a commonly used indicator for evaluating the nutritional value of food protein, using essential amino acids from egg protein as the evaluation standard. A higher EAAI value indicates a more balanced amino acid composition and higher protein quality and utilization. Comparison shows that the EAAI value of the muscle of high-body juvenile amberjack raised using the artificial compound feed from Example 1 (which replaced fresh fish) is higher. This indicates that the artificial compound feed from Example 1 improves the amino acid composition balance of the muscle, resulting in higher protein quality and utilization, and thus increasing the protein value of the muscle. This is because the feed contains limiting essential amino acids (Lys and Met), meeting the fish's amino acid requirements. The content of limiting essential amino acids is a crucial factor affecting amino acid balance. If the amino acid ratio is imbalanced, even if the content of other non-limiting amino acids is high, they cannot be fully absorbed and utilized. The artificial compound feed from Example 1 of this invention improves the amino acid balance in fish by supplementing them with limiting essential amino acids (Lys and Met), thereby increasing amino acid utilization, promoting amino acid resynthesis, and further promoting protein production, thus increasing the protein content in the muscle of high-body amberjack. In addition, the taurine added in this invention promotes the synthesis of sulfur-containing amino acids such as cystine and methionine in the body, and the phospholipids reduce the consumption of methionine, which also plays an important role in increasing the content of amino acids and promoting amino acid balance.

[0113] The results of the evaluation of the amino acid composition and content of high-body yellowtail juvenile muscle and the nutritional value of essential amino acids showed that the artificial compound feed for high-body yellowtail juvenile fish in Example 1, which replaced fresh fish, can improve the amino acid content, amino acid composition balance, protein quality and utilization rate of muscle, as well as improve the flavor of high-body yellowtail muscle, without affecting the protein edible value.

[0114] 5. Expression levels of growth-related genes in the muscles of juvenile amberjack.

[0115] The expression levels of growth-related genes in the muscle of juvenile amberjacks fed with artificial formulated feed (as a substitute for fresh fish in Example 1) and juvenile amberjacks fed with fresh mixed fish in Comparative Example 1 were compared, and the results are shown in Figure 1.

[0116] As shown in Figure 1, compared with the muscle samples of high-body yellowtail juveniles fed with fresh fish in Comparative Example 1, the expression levels of myopoietin (MyoG), myogenic differentiation factor 1 (MyoD1), myogenic differentiation factor 2 (MyoD2), and type I collagen encoding gene (COL1A1A) were significantly increased in the muscle of high-body yellowtail juveniles fed with artificial formulated feed that replaced fresh fish in Example 1 (P<0.05).

[0117] Genes MyoD and MyoG belong to the myogenic regulatory factors (MRFs) family and are involved not only in myocyte proliferation, myogenic differentiation, and myofibril formation, but also play an important role in the maturation, fusion, and functional development of individual myocytes. In the early stages of muscle development, MyoD acts as a myogenic determinant, regulating myoblast proliferation; later, MyoG assumes the function of myoblast fusion and differentiation. In this invention, the relative expression levels of genes MyoG, MyoD1, and MyoD2 in the muscles of high-bodied amberjack juveniles fed with the feed of Comparative Example 1 were significantly increased, indicating that the artificial formulated feed of Example 1 can promote the growth and differentiation of myocytes and the significant thickening of muscle fibers in high-bodied amberjack juveniles.

[0118] The gene COL1A1A encodes the peptide chain of α1 collagen, and type I collagen is the main component of collagen in fish muscle and skin. Collagen plays a crucial role in maintaining tissue structure stability and integrity, and is an important factor affecting muscle quality. Increased collagen content in fish muscle results in higher muscle firmness. In this invention, the relative expression level of COL1A1A in the muscle of high-body juvenile yellowtail fish fed to Comparative Example 1 was significantly increased, indicating that the artificial formulated feed of Example 1 can promote the expression of the gene encoding collagen, increase collagen content, and improve the firmness of the muscle in the formulated feed group.

[0119] The results of the analysis of the expression levels of growth-related genes in the muscles of juvenile amberjack showed that the nutritional level of the formulated feed in Example 1 can regulate the muscle growth and meat flavor of juvenile amberjack by modulating the expression of growth and meat quality-related genes in the muscles.

[0120] Based on the above experiments, the artificial formulated feeds for high-body amberjack juveniles in Examples 1-4 of this invention, which replace chilled fish, are suitable for amberjack juvenile farming. These formulated feeds have a scientifically balanced ratio of raw materials, a low feed conversion ratio, and can reduce farming costs. Furthermore, the artificial formulated feed for high-body amberjack juveniles in Example 1, which replaces chilled fish, can also improve the protein nutritional value and flavor of high-body amberjack juveniles. The artificial formulated feeds of this invention also have advantages such as easy storage, convenient feeding, good water stability, and low risk of polluting the aquaculture water quality, which are beneficial for the large-scale farming of high-body amberjack juveniles.

[0121] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A formulated feed for high-body amberjack juveniles as an alternative to chilled fish, characterized in that, It comprises the following components by weight: 40-47 parts super steamed fish meal, 5-10 parts high-gluten flour, 5-10 parts peeled soybean meal, 5-7 parts chicken meal, 5-7 parts wheat gluten, 5-10 parts whole shrimp meal, 5-7 parts fermented soybean meal, 3-5 parts soybean oil, 3-5 parts fish oil, 1.0-1.5 parts calcium dihydrogen phosphate, 0.4-1.0 parts vitamin mixture, 0.5-1.0 parts mineral mixture, 1-2 parts phospholipids, 0.2 parts choline, 0.1 parts vitamin C phosphate, 0.1 parts taurine, 0.1 parts lysine, and 0.1 parts methionine.

2. The formulated feed for high-body amberjack juveniles as a substitute for chilled fish according to claim 1, characterized in that, The crude protein content of the dehulled soybean meal is 46%.

3. The formulated feed for high-body amberjack juveniles as a substitute for chilled fish according to claim 1, characterized in that, Each 100g of the vitamin mixture comprises the following components: Vitamin A 4 million IU-8 million IU, Vitamin E 2g-2.4g, Vitamin D3 3 million IU-3.8 million IU, Vitamin K 0.01g-0.08g, Vitamin C 3.3g-3.7g, Vitamin B1 0.5g-1g, Vitamin B2 0.6g-1g, Vitamin B3 4.6g-5g, Vitamin B5 1g-1.5g, Vitamin B6 0.3g-0.6g, Vitamin B9 0.4g-0.7g, Vitamin B... 12 0.03g-0.07g, Biotin 0.02g-0.05g, Inositol 17g-20g, Cellulose 50g-70g.

4. The formulated feed for high-body amberjack juveniles as a substitute for chilled fish according to claim 1, characterized in that, The mineral mixture per 100g contains the following components: potassium 2.5g-3g, iron 5g-15g, sodium 2g-5g, cobalt 0.1g-0.4g, magnesium 5g-8g, iodine 3g-6g, zinc 5g-15g, selenium 0.2g-0.5g, manganese 2g-8g, and copper 2g-5g.

5. The formulated feed for high-body amberjack juveniles as a substitute for chilled fish according to claim 1, characterized in that, The phospholipid has a purity of 55%.

6. The formulated feed for high-body amberjack juveniles as a substitute for chilled fish according to claim 1, characterized in that, The purity of the choline is 50%.

7. The application of the artificial compound feed for high-body yellowtail juveniles as described in any one of claims 1-6 in improving the nutritional composition of the muscle and enhancing the flavor of the meat of high-body yellowtail juveniles.

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