A method for artificial breeding of yellow catfish

Abstract

This invention discloses an artificial breeding method for yellow catfish, relating to the field of animal husbandry technology. The breeding method includes: (1) artificially hybridizing yellow catfish and long-snout catfish as parents to obtain a binary hybrid fish; (2) artificially hybridizing the binary hybrid fish and yellow catfish as parents to obtain a ternary hybrid yellow catfish. The breeding method of this invention, through specific selection and matching of hybrid parents, enables the excellent genetic resources of the three parents to be inherited synchronously and stably during the ternary hybridization process, thereby stably obtaining a new fish variety with fast growth rate, good stress resistance, high fish meat quality and good disease resistance, which is of great significance for ensuring the long-term supply of high-quality aquatic products and promoting the high-quality development of fisheries.

Description

Technical Field

[0001] This invention relates to the field of animal husbandry technology, mainly to the field of fish breeding technology, and specifically to a method for artificial breeding of yellow catfish. Background Technology

[0002] Yellow catfish (Pelteobagrus fulvidraco), also known as angci fish, angding fish, yellow bone fish, yellow duck, and yellow hot catfish, belongs to the order Siluriformes, family Bagridae, and genus Pelteobagrus. It is widely distributed in the Pacific water systems of eastern China. This fish is relatively small, typically 123-143 mm in length. Its flesh is tender and boneless, rich in protein, amino acids, and various trace elements. It has both high edible and medicinal value and is one of China's important freshwater aquaculture species.

[0003] In recent years, with the continuous improvement of residents' living standards, consumers' demand for high-quality aquatic products has been increasing. Yellow catfish, due to its delicate taste, rich nutrition, and ease of consumption, has seen a continuous rise in market demand. However, wild yellow catfish resources are limited and production is extremely low, long unable to meet market demand. Artificial farming has become the main source of yellow catfish supply.

[0004] However, in the practice of artificial breeding of yellow catfish, there are many technical bottlenecks that restrict the development of the industry: 1. Slow growth rate and long breeding cycle; it takes a long time for ordinary yellow catfish to grow from fry to marketable size, resulting in low capital turnover efficiency and limited breeding benefits. 2. Low fry survival rate and high breeding costs; yellow catfish fry have poor resistance to stress and have strict requirements for water quality, dissolved oxygen, and feed. The loss during the fry cultivation process is large, directly increasing the breeding cost. 3. Poor tolerance to low oxygen and high transportation losses; yellow catfish have a strong stress response under intensive transportation conditions and are prone to death from hypoxia or body surface damage ("blemishes"), resulting in a low survival rate of marketable fish during transportation and a significant increase in distribution costs.

[0005] The aforementioned problems have severely restricted the large-scale and intensive development of the yellow catfish industry. Therefore, breeding new yellow catfish varieties with fast growth rate, high seedling survival rate, strong resistance to adverse conditions, good transportability, and excellent quality is of great significance for promoting industrial upgrading.

[0006] In response to the aforementioned industry demands, domestic research institutions have conducted systematic breeding programs for improved varieties of yellow catfish. In 2018, the "Huangyou No. 1" (variety registration number: GS-02-001-2018), bred by Professor Fan Qixue's team at the College of Fisheries, Huazhong Agricultural University, was approved by the National Aquatic Original and Improved Variety Approval Committee and became a national new aquatic variety, and was selected as one of China's Major Agricultural and Rural New Products in 2021. This variety was bred through hybridization using yellow catfish as the female parent and Pelteobagrus vachelli as the male parent. Pelteobagrus vachelli, also known as river catfish or hard-horned yellow catfish, belongs to the order Siluriformes, family Bagridae, and genus Pelteobagrus. It is relatively large, with a maximum body length of up to 300 mm. Its body is elongated and laterally compressed at the posterior end. The flesh is tender, delicious, and nutritious, making it an important freshwater economic fish.

[0007] "Huangyou No. 1" exhibits significant advantages over ordinary yellow catfish in several traits: the weight of one-year-old fish is increased by 29.39% to 32.72%, the survival rate of fry is increased by more than 30%, and the tolerance to low oxygen and transportation performance are significantly improved, effectively alleviating some of the technical bottlenecks in traditional aquaculture. It has now become the main variety of artificially farmed yellow catfish, and its promotion covers more than 20 provinces.

[0008] However, "Huangyou No. 1" still has the following shortcomings: 1. Smaller commercial size; limited by the size of the parent yellow catfish, the adult weight of "Huangyou No. 1" still has room for improvement, making it difficult to meet the market demand for larger commercial fish. 2. Slightly inferior meat quality compared to the parent; the hybrid offspring have lower accumulation of flavor substances compared to purebred yellow catfish, affecting the end-consumer experience. 3. Growth rate and survival rate still have potential for improvement; the existing hybrid combinations have not fully utilized the genetic complementarity effect between different species within the yellow catfish genus, and the extent of trait improvement can still be further expanded.

[0009] Therefore, creating a new type of yellow catfish that combines rapid growth, high survival rate, large size, and excellent meat quality has become an urgent technical problem to be solved in the field of yellow catfish genetic breeding. It is of great practical significance for improving industrial efficiency, ensuring the supply of high-quality aquatic products, and promoting the high-quality development of fisheries. Summary of the Invention

[0010] The purpose of this invention is to provide an artificial breeding method for hybrid yellow catfish that combines rapid growth and large body size.

[0011] To achieve the above objectives, the present invention provides an artificial breeding method for yellow catfish, comprising the following steps: (1) using yellow catfish and long-snout catfish as parents to carry out one artificial hybridization breeding to obtain a binary hybrid fish; (2) using the binary hybrid fish and yellow catfish as parents to carry out a second artificial hybridization breeding to obtain a ternary hybrid yellow catfish.

[0012] In step (1), the long-snout catfish (Leiocassis longirostris) is a species of fish belonging to the order Siluriformes, family Leiocasidae, and genus Leiocassis. It is commonly known as Jiangtuan, Baiji, Feitouyu, and Kuiyu. The long-snout catfish is a prized freshwater fish in my country. It has a stout, elongated body, a bulging abdomen, and a laterally compressed tail. Individual long-snout catfish vary in weight, generally weighing 1500-2500 grams, with a few reaching up to 10 kilograms. The long-snout catfish has tender, delicious flesh, no fine bones, and is rich in protein, fat, and various vitamins, making it a top-grade freshwater edible fish.

[0013] Preferably, the specific steps of the first artificial hybridization breeding include: artificially inducing estrus in gonadally mature yellow catfish and long-snout catfish; artificially inseminating the estrus-inducing broodstock; hatching the fertilized eggs to obtain hybrid fish fry; and raising the hybrid fish fry to obtain hybrid fish parent stock.

[0014] Preferably, the incubation conditions for the fertilized eggs are: water temperature 25-28℃ and oxygen content 6-10mg / L; under these preferred conditions, the hatching rate of the fertilized eggs is higher.

[0015] Preferably, the rearing conditions for the binary hybrid fish are: water temperature 15-35℃ and oxygen content 4-10mg / L; under these preferred rearing conditions, the binary hybrid fish grow faster and have a lower disease rate.

[0016] In step (2), preferably, the specific steps of the secondary artificial hybridization breeding include: artificially inducing estrus in mature yellow catfish broodstock and binary hybrid broodstock; artificially inseminating the estrus broodstock; and hatching the fertilized eggs to obtain ternary hybrid yellow catfish.

[0017] Preferably, the rearing water temperature for artificially induced spawning of yellow catfish is 25-30℃; more preferably, it is 27-29℃. If the water temperature is too low, the estrus period of yellow catfish will be delayed; if the water temperature is too high, the success rate of artificial insemination will be reduced.

[0018] Preferably, the hormones used to induce artificial spawning in the parent fish of the binary hybrid fish include luteinizing hormone-releasing hormone analogue (LRHA2), human chorionic gonadotropin (HCG), and dioxin (DOM).

[0019] Preferably, the dosage of artificial spawning hormones used in the parent fish of the binary hybrid fish is as follows: 5-10 μg / kg of luteinizing hormone-releasing hormone analogue, 1000-1500 IU / kg of human chorionic gonadotropin, and 2-5 mg / kg of dioxin.

[0020] Preferably, the rearing water temperature for the parent fish of the binary hybrid fish after artificial spawning is 23-27℃; more preferably 24-25℃; if the water temperature is too low, the estrus period of the binary hybrid fish will be delayed; if the water temperature is too high, the success rate of artificial insemination will be reduced.

[0021] Preferably, the incubation conditions for the fertilized eggs are: water temperature 22-30℃ and oxygen content 8-12mg / L; more preferably, the incubation conditions for the fertilized eggs are: first incubation under the first condition (preferably water temperature 23-25℃ and oxygen content 8-12mg / L) for 12-24 hours, and then incubation under the second condition (preferably water temperature 27-29℃ and oxygen content 8-10mg / L), wherein the water temperature of the first condition is lower than that of the second condition, and the oxygen content of the first condition is higher than that of the second condition; the preferred incubation conditions can significantly improve the hatching rate of the fertilized eggs.

[0022] Preferably, in step (1), artificial hybridization is carried out once using yellow catfish as the female parent and long-snout catfish as the male parent to obtain a binary hybrid fish; the preferred male and female parent varieties of the binary hybrid fish can better preserve and integrate the genetic resources of the two species, so that the resulting binary hybrid offspring have more superior and stable traits, especially significantly improving the body size (weight) of the offspring of the three-way hybrid fish, providing the best parents for subsequent three-way hybridization.

[0023] More preferably, in step (2), a second artificial hybridization is carried out using a binary hybrid fish as the father and a yellow catfish as the mother to obtain a ternary hybrid yellow catfish; the preferred parent fish varieties can better preserve and integrate the genetic resources of the three species, so that the resulting ternary hybrid offspring have more superior and stable traits, especially significantly improving the fish meat quality and disease resistance of the ternary hybrid fish offspring.

[0024] The beneficial effects of this invention are: 1. The artificial breeding method for yellow catfish of this invention, influenced by the distant hybridization method and the special combining ability between the parents, accidentally discovered that the three-way hybridization of yellow catfish, long-snout catfish and yellow catfish as parents can effectively integrate the excellent genetic resources of the three parents, so that the resulting three-way hybrid yellow catfish can achieve simultaneous optimization in traits such as growth rate, stress resistance, body size and fish meat quality. Thus, a new fish variety with fast growth rate, good stress resistance, large body size, high fish meat quality and good disease resistance can be artificially bred.

[0025] 2. The artificial breeding method for yellow catfish of the present invention, through specific selection and mating of hybrid parents, enables the stable inheritance of the excellent genetic resources of the three parents during the three-way hybridization process, thereby stably obtaining a new fish variety with fast growth rate, good stress resistance, large body size, high fish meat quality and good disease resistance. This is of great significance for ensuring the long-term supply of high-quality aquatic products and promoting the high-quality development of fisheries.

[0026] 3. The artificial breeding method for yellow catfish of the present invention has a high artificial fertilization rate and a high hatching rate of fertilized eggs. Attached Figure Description

[0027] Figure 1 This is a photograph of the binary hybrid fish (paternal parent) obtained by artificial hybridization in Example 1 of the present invention; Figure 2 The image shows a photograph of the three-way hybrid yellow catfish obtained through secondary artificial hybridization in Example 1 of this invention. Figure 3 This is a photograph of the actual fish fry (fry) of the three-way hybrid yellow catfish in Example 1 of the present invention. Detailed Implementation

[0028] The technical solution of the present invention will be further described in detail below with reference to the embodiments.

[0029] Examples 1-4

[0030] The specific steps for the artificial breeding of a type of yellow catfish are as follows: (1) Artificial hybridization was carried out using yellow catfish and long-snout catfish as parents (the specific selection of parent fish is shown in Table 1) to obtain binary hybrid fish ( Figure 1 (as shown) Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 25℃, raised until estrus) and longsnout catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg DOM) were raised until estrus. The fish were artificially induced to spawn (at a water temperature of 25℃ and LRHA2 / kg + DOM / kg). The broodstock were then artificially inseminated (the eggs and sperm were manually squeezed out and mixed at 25℃). The fertilized eggs were incubated (at a water temperature of 26℃ and an oxygen content of 8mg / L until hatching) to obtain hybrid fish fry. The hybrid fish fry were then raised (at a water temperature of 25℃ and an oxygen content of 5mg / L) until gonadal maturity to obtain the parent hybrid fish. (2) Using binary hybrid fish and yellow catfish as parents, a second artificial hybridization was carried out (the specific selection of parents is shown in Table 1) to obtain ternary hybrid yellow catfish (e.g. Figure 2 (as shown) Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 28℃, raised until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 28℃, raised until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; raised until estrus) and hybrid fish broodstock (second injection: 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 28℃, raised until estrus) and hybrid fish broodstock (second ... The fish were fed with HCG (kg), LRHA (8μg / kg), and DOM (5mg / kg) at a water temperature of 25℃ until they came into estrus. Artificial spawning was then induced. After estrus, the parent fish were artificially inseminated (the eggs and sperm were manually squeezed out and mixed at 26℃). The fertilized eggs were then incubated (first at 24℃ and 10mg / L oxygen for 20 hours, then at 28℃ and 9mg / L oxygen until hatching), resulting in three-way hybrid yellow catfish fry. Figure 3 (As shown); the three-way hybrid yellow catfish fry can be released into the fishpond after being raised in the hatching pond for 24 hours.

[0031] Table 1. Selection of broodstock for artificial hybridization in Examples 1-4 .

[0032] Example 5

[0033] The specific steps for the artificial breeding of a type of yellow catfish are as follows: (1) Artificial hybridization was carried out using yellow catfish and long-snout catfish as parents (the specific selection of parent fish was the same as in Example 1) to obtain binary hybrid fish; Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8-hour interval): 1200 IU / kg HCG + 10 μg / kg LRHA2 + 2 mg / kg DOM; water temperature 23℃, raised until estrus) and longsnout catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8-hour interval): 1200 IU / kg HCG + 10 μg ..., raised until estrus) and longsnout catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8-hour interval): 1200 IU / kg HCG + 10 μg / kg DOM, raised until estrus) and longsnout catfish broodstock (second injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8-hour interval): 1200 IU / kg HCG + 10 μg / kg DOM, raised until estrus) and longsnout catfish broodstock (second injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; water temperature 23℃, raised until estrus) and longsnout catfish broodstock (second injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8-hour interval): 1200 IU / kg HCG + 10 μg / kg The fish were artificially induced to spawn (using g / kg LRHA2 and 2mg / kg DOM, and raised at 23℃ until estrus); the broodstock were then artificially inseminated (the eggs and sperm were manually squeezed out and mixed at 25℃); the fertilized eggs were incubated (at 25℃ and 6mg / L oxygen) to obtain hybrid fish fry; the hybrid fish fry were then raised (at 28℃ and 4mg / L oxygen) until gonadal maturity to obtain hybrid fish parent stock. (2) Using binary hybrid fish and yellow catfish as parents, a second artificial hybridization was carried out (the specific selection of parents is the same as in Example 1) to obtain ternary hybrid yellow catfish; Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1200 IU / kg HCG + 10 μg / kg LRHA2 + 2 mg / kg DOM; water temperature 27℃, raised until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1200 IU / kg HCG + 10 μg / kg LRHA2 + 2 mg / kg DOM; raised at 27℃ until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1200 IU / kg HCG + 10 μg / kg LRHA2 + 2 mg / kg DOM) RHA2+2mg / kg DOM; reared at 23℃ until estrus) artificially induced spawning; after estrus, the parent fish were artificially inseminated (the eggs and sperm of the parent fish were artificially squeezed out and mixed at 26℃); the fertilized eggs were incubated (first incubated at 23℃ and oxygen content of 12mg / L for 12 hours, and then incubated at 27℃ and oxygen content of 10mg / L until hatching), to obtain three-way hybrid yellow catfish fry; the three-way hybrid yellow catfish fry were reared in the incubation pond for 24 hours before being released into the fish pond for rearing.

[0034] Example 6

[0035] The specific steps for the artificial breeding of a type of yellow catfish are as follows: (1) Artificial hybridization was carried out using yellow catfish and long-snout catfish as parents (the specific selection of parent fish was the same as in Example 1) to obtain binary hybrid fish; Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1500 IU / kg HCG + 5 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 27℃, raised until estrus) and longsnout catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1500 IU / kg HCG + 5 μg / kg DOM) were raised until estrus. / kg LRHA2 + 5mg / kg DOM; raised at 27℃ until estrus) were artificially induced to estrus; the estrus-inducing parent fish were artificially inseminated (at 25℃, the parent fish eggs and sperm were artificially squeezed out and mixed); the fertilized eggs were hatched (at 28℃ and 10mg / L oxygen content until hatching) to obtain hybrid fish fry; the hybrid fish fry were raised (at 28℃ and 4mg / L oxygen content) until gonadal maturity to obtain hybrid fish parent fish; (2) Using binary hybrid fish and yellow catfish as parents, a second artificial hybridization was carried out (the specific selection of parents is the same as in Example 1) to obtain ternary hybrid yellow catfish; Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1500 IU / kg HCG + 5 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 29℃, raised until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1500 IU / kg HCG + 5 μg / kg LRHA2 + 5 mg / kg DOM; raised at 29℃ until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1500 IU / kg HCG + 5 μg / kg LRHA2 + 5 mg / kg DOM) RHA2+5mg / kg DOM; reared at 27℃ until estrus) artificially induced spawning; after estrus, the parent fish were artificially inseminated (the eggs and sperm of the parent fish were artificially squeezed out and mixed at 26℃); the fertilized eggs were incubated (first incubated at 25℃ and 8mg / L oxygen for 24 hours, and then incubated at 29℃ and 9mg / L oxygen until hatching) to obtain three-way hybrid yellow catfish fry; the three-way hybrid yellow catfish fry were reared in the incubation pond for 24 hours before being released into the fishpond for rearing.

[0036] Example 7

[0037] The specific steps for the artificial breeding of a type of yellow catfish are as follows: (1) Artificial hybridization was carried out using yellow catfish and long-snout catfish as parents (the specific selection of parent fish was the same as in Example 1) to obtain binary hybrid fish; Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8h interval): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 25℃, raised until estrus) and longsnout ..., raised until estrus) and longsnout catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8h interval): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM, raised until estrus) and longsnout catfish broodstock (second injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8h interval): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM, raised until estrus) and longsnout catfish broodstock (second injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; water temperature 25℃, raised until estrus) and longsnout catfish broodstock (second injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg The fish were artificially induced to spawn (using μg / kg LRHA2 and 5mg / kg DOM, and raised at 25℃ until estrus). The broodstock were then artificially inseminated (the eggs and sperm were manually squeezed out and mixed at 25℃). The fertilized eggs were hatched (at 25℃ and 6mg / L oxygen) to obtain hybrid fish fry. These fry were then raised at 28℃ and 4mg / L oxygen until gonadal maturity to obtain the parent hybrid fish. (2) Using binary hybrid fish and yellow catfish as parents, a second artificial hybridization was carried out (the specific selection of parents is the same as in Example 1) to obtain ternary hybrid yellow catfish; Sexually mature yellow catfish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 28℃, raised until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 28℃, raised until estrus) and hybrid fish broodstock (first injection: 0.5 μg / kg LRHA2 + 0.8 mg / kg DOM; second injection (8 hours later): 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; raised until estrus) and hybrid fish broodstock (second injection: 1400 IU / kg HCG + 8 μg / kg LRHA2 + 5 mg / kg DOM; water temperature 28℃, ...half-breeding) and hybrid fish broodstock (half-breeding) and hybrid fish broodstock (hal HCG + 8μg / kg LRHA2 + 5mg / kg DOM; raised at 25℃ until estrus is induced by artificial spawning; the broodstock are then artificially inseminated (the eggs and sperm are artificially squeezed out and mixed at 25℃); the fertilized eggs are incubated (incubated at 27℃ and 9mg / L oxygen until hatching) to obtain three-way hybrid yellow catfish fry; these three-way hybrid yellow catfish fry are raised in the incubation pond for 24 hours before being released into the fishpond for rearing.

[0038] Example 8

[0039] A yellow catfish was artificially bred using the same method as in Example 1, except that the fertilized eggs in the secondary artificial hybridization breeding were incubated under the following conditions: first at 28°C and with an oxygen content of 10 mg / L for 20 hours, and then at 24°C and with an oxygen content of 9 mg / L until hatching.

[0040] Comparative Examples 1-9

[0041] The specific steps of the artificial breeding method for a hybrid yellow catfish are the same as those in Example 1, except that the specific selection of parent fish is different, as shown in Table 2.

[0042] Table 2 Selection of broodstock for artificial hybridization in Comparative Examples 1-9 .

[0043] Experimental Example 1: 1. Fish meat quality test Testing method: Expert scoring was used to evaluate the quality of the fish meat. The expert panel consists of 20 professionally trained sensory evaluators; half male and half female, aged 20-45, in good health, and without olfactory / gustatory disorders; they must receive professional training before the formal evaluation and be familiar with the scoring criteria and reference samples.

[0044] Samples: Randomly coded (three-digit number), uniformly cooked before evaluation.

[0045] Scoring rules: Total score = Aroma score + Taste score + Texture score + Color score

[0046] Odor (30 points), the scoring criteria are as follows:

[0047] Taste (30 points), the scoring criteria are as follows:

[0048] Texture (30 points), the scoring criteria are as follows:

[0049] Color and appearance (10 points), the scoring criteria are as follows:

[0050] The 1-year-old hybrid fish from Examples 1-4 and Comparative Examples 1-9 were subjected to fish meat quality testing, and the results are shown in Table 3: Table 3 Results of fish meat quality testing

[0051] 2. Growth rate test: For the hybrid fish fry in Examples 1-4 and Comparative Examples 1-9, under the same feeding conditions, 20 fish were randomly caught, and the average weight (g) of individuals at different age stages (1 month, 6 months, 1 year, 2 years, 3 years) was measured. The results are shown in Table 4. Table 4. Growth rate test results

[0052] 3. Disease resistance and stress resistance tests

[0053] The survival rate and disease rate of the hybrid fish fry (from fry to summer fry) in Examples 1-4 and Comparative Examples 1-9 were statistically analyzed under the same feeding conditions. (After 60 days of conventional culture, 50 fish were randomly collected from 10 different areas of the pond using a dip net, and the number of fish with diseases (ascites and ulcer disease) was counted to calculate the disease rate). The mortality rate of the fish (1-year-old fish) after 6 hours of transportation under the same conditions (normal temperature and oxygenation) was also analyzed. The results are shown in Table 5.

[0054] Table 5 Results of disease resistance and stress resistance tests

[0055] Analysis of the experimental data in Tables 3, 4, and 5 shows that in Examples 1-4 of this invention, the three-way hybrid offspring obtained by first-crossing breeding of *Pelteobagrus vachelli* and *Catfish bream* as parents, followed by second-crossing breeding using the offspring of the first-crossing with *Pelteobagrus vachelli* as parents, exhibit excellent growth rate, weight, flesh quality, and disease resistance. In particular, compared to existing binary hybrid *Pelteobagrus vachelli* (Comparative Example 9), its growth rate and weight are significantly improved. Furthermore, through specific mating of the first-crossing (Example 2) and second-crossing parent fish (Example 1) of this application, the resulting three-way hybrid offspring show significant improvements in weight, flesh quality, and disease resistance. In contrast, in Comparative Examples 1-8, by changing the parent mating, the resulting three-way hybrid offspring showed a significant decrease in traits. Therefore, the superior traits of the three-way hybrid *Pelteobagrus vachelli* of this application can only be obtained through artificial breeding under specific parent mating conditions.

[0056] Experiment Example 2

[0057] The fertilization rate and hatching rate of fish eggs during the first and second artificial hybridization breeding processes in Examples 1, 5, 6, 7, and 8 were statistically analyzed. The specific results are shown in Table 6. Table 6. Statistical results of fish egg fertilization rate and hatching rate

[0058] Analysis of the data in Table 5 shows that, under specific incubation conditions, the hatching rate of fertilized eggs of three-way hybrid yellow catfish can be significantly improved in the artificial breeding method of the present invention, which is beneficial to the large-scale breeding of three-way hybrid yellow catfish.

[0059] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for artificial breeding of Pelteobagrus vachelli, characterized in that, Includes the following steps: (1) Using yellow catfish and long-snout catfish as parents, a second artificial hybridization was carried out to obtain a two-way hybrid fish; (2) Using the two-way hybrid fish and yellow catfish as parents, a second artificial hybridization was carried out to obtain a three-way hybrid yellow catfish.

2. The artificial breeding method of Pelteobagrus vachelli according to claim 1, characterized in that, In step (1), the specific steps of the artificial hybridization breeding include: artificially inducing estrus in the gonad-mature yellow catfish and long-snout catfish; artificially inseminating the estrus-inducing broodstock; hatching the fertilized eggs to obtain hybrid fish fry; and raising the hybrid fish fry to obtain hybrid fish parent stock.

3. The artificial breeding method of the yellow catfish according to claim 2, characterized in that, The incubation conditions for the fertilized eggs are: water temperature 25-28℃, oxygen content 6-10mg / L.

4. The artificial breeding method of Pseudobrama sima according to claim 2, characterized in that, The rearing conditions for the hybrid fish are: water temperature 15-35℃, oxygen content 4-10mg / L.

5. The artificial breeding method of Pseudobrama sima according to claim 1, characterized in that, In step (2), the specific steps of the secondary artificial hybridization breeding include: artificially inducing estrus in mature yellow catfish and binary hybrid fish; artificially inseminating the estrus-inducing fish; and hatching the fertilized eggs to obtain ternary hybrid yellow catfish.

6. The artificial breeding method for yellow catfish according to claim 5, characterized in that, The hormones used to induce artificial spawning in the parent fish of the binary hybrid fish include luteinizing hormone-releasing hormone analogs, human chorionic gonadotropin, and dioxin.

7. The artificial breeding method for yellow catfish according to claim 5, characterized in that, The rearing water temperature for the parent fish of the binary hybrid fish after artificial spawning is 23-27℃; preferably 24-25℃.

8. The artificial breeding method for yellow catfish according to claim 5, characterized in that, The incubation conditions for the fertilized eggs are: water temperature 22-30℃, oxygen content 8-12mg / L; preferably, the incubation conditions for the fertilized eggs are: first incubating for 12-24 hours under the first condition, and then incubating under the second condition, wherein the water temperature under the first condition is lower than that under the second condition, and the oxygen content under the first condition is higher than that under the second condition.

9. The method for artificially breeding yellow catfish according to any one of claims 1-8, characterized in that, In step (1), artificial hybridization was carried out using Yellow Catfish as the female parent and Long-snout Catfish as the male parent to obtain a binary hybrid fish.

10. The method for artificially breeding yellow catfish according to claim 9, characterized in that, In step (2), a second artificial hybridization was carried out using the binary hybrid fish as the male parent and the yellow catfish as the female parent to obtain the ternary hybrid yellow catfish.

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