Alkali-resistant grass carp strain breeding method

Abstract

The invention provides an alkali-resistant grass carp strain breeding method, and belongs to the technical field of aquaculture. The method comprises the following steps: capturing wild parent fishes in the breeding season of the small sea grass carps, selfing in a water body containing low-concentration NaHCO3, collecting fertilized eggs, transferring the fertilized eggs into a hatching pond, and hatching to obtain an F1 generation; when the F1 generation grows to 1-2 cm, transferring the F1 generation into a water body containing high-concentration NaHCO3 for culture, and screening an alkali-resistant F1 generation; transferring the alkali-resistant F1 generation into a water body containing low-concentration NaHCO3 to be cultured for alkali-resistant breeding of the next generation; and continuously breeding for 3-4 generations to obtain the alkali-resistant grass carp. According to the method disclosed by the invention, the alkali-resistant grass carp can be obtained by taking the wild parent fish of the small sea grass carp as a breeding basis and adopting NaHCO3 solution stress through multi-generation breeding, so that a basis is provided for promoting the development of the culture industry in saline-alkali water areas.

Description

Technical Field

[0001] The invention belongs to the technical field of aquaculture, and in particular relates to a strain breeding method of alkali-resistant grass carp. Background Art

[0002] The water quality of saline-alkali water is complex, with high alkalinity and pH, which leads to low survival rate and low yield of freshwater fish fry breeding, making most saline-alkali waters idle and unable to be effectively utilized, restricting the large-scale development of the aquaculture industry.

[0003] Grass carp belongs to the genus Grass carp of the Cyprinidae family, subfamily Leucophaga, order Cypriniformes, and is one of the four major freshwater carps in China. Grass carp is rich in unsaturated fatty acids, which are beneficial to blood circulation and are a good food for cardiovascular patients; it is rich in selenium, and regular consumption has anti-aging and beauty effects, and also has a certain preventive and therapeutic effect on tumors; for people with thin bodies and poor appetite, grass carp meat is tender and not greasy, which can stimulate appetite and nourish. In view of the low utilization rate of waters in high-alkali areas and the lack of suitable aquaculture varieties, a breeding method for alkali-resistant grass carp is provided, which is conducive to promoting the development of aquaculture industry in saline-alkali waters. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a method for breeding alkali-resistant grass carp, which can breed alkali-resistant grass carp and provide a basis for promoting the development of aquaculture industry in saline-alkali waters.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] A method for breeding alkali-resistant grass carp comprises the following steps: capturing wild broodstock during the breeding season of grass carp in Xiaohaizi, 3 The fertilized eggs were collected and transferred to the hatching pond to obtain the F1 generation after hatching. When the F1 generation grew to 1-2 cm, they were transferred to a water pond containing high concentration of NaHCO. 3 The alkaline-resistant F1 generation was cultured in water containing low concentration of NaHCO 3 The fish are cultivated in water bodies for alkali-resistant breeding of the next generation; after continuous breeding for 3 to 4 generations, the alkali-resistant grass carp is obtained.

[0007] Preferably, the low concentration of NaHCO 3 NaHCO in water 3 The concentration is 10-15mmol / L.

[0008] Preferably, the high concentration of NaHCO 3 NaHCO in water 3 The concentration is 30~48mmol / L.

[0009] Preferably, the incubation conditions of the fertilized eggs are: water temperature 20-28°C, NaHCO 3 The concentration is 5-10mmol / L, pH value is 7.5-8.2, and dissolved oxygen is 5-8mg / L.

[0010] Preferably, the male-to-female ratio of the wild broodstock is 2 to 3:1.

[0011] Preferably, wild broodstock are captured in Xiaohaizi Reservoir.

[0012] Preferably, the gonads of wild Xiaohaizi grass carp broodstock develop to stage V.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The present invention provides a breeding method for alkali-resistant grass carp, which uses wild broodstock of grass carp from Xiaohaizi as breeding basis, adopts different concentrations of NaHCO 3 The solution is used to stress grass carp at different stages. After multiple generations of breeding, alkali-resistant grass carp can be obtained, which provides a basis for promoting the development of aquaculture industry in saline-alkali waters. DETAILED DESCRIPTION

[0015] The present invention provides a breeding method for alkali-resistant grass carp, comprising the following steps: capturing wild broodstock in a small lake during the grass carp breeding season, 3 The fertilized eggs were collected and transferred to the hatching pond to obtain the F1 generation after hatching. When the F1 generation grew to 1-2 cm, they were transferred to a water pond containing high concentration of NaHCO. 3 The alkaline-resistant F1 generation was cultured in water containing low concentration of NaHCO 3 The fish are cultivated in water bodies for alkali-resistant breeding of the next generation; after continuous breeding for 3 to 4 generations, the alkali-resistant grass carp is obtained.

[0016] The present invention captures wild broodstock in the Xiaohaizi Reservoir during the breeding season of Xiaohaizi grass carp. The Xiaohaizi grass carp is plump and healthy, with delicate and smooth meat, no peculiar smell, delicious, pure and chewy taste, and is an excellent breeding variety. The Xiaohaizi Reservoir is located in the Xiaohaizi depression in the alluvial plain of the lower reaches of the Yarkand River at the northwest edge of the Tarim Basin. The water is clear, clean and weakly alkaline, and the natural bait in the reservoir is very rich, which is very suitable for the growth of aquatic animals. The present invention uses the wild broodstock of Xiaohaizi grass carp captured in the Xiaohaizi Reservoir as the breeding basis to help obtain alkali-resistant grass carp strains.

[0017] The gonads of the wild broodstock of grass carp captured in the present invention have developed to stage V, and the captured wild broodstock are transferred to a breeding pond for breeding. The water in the breeding pond contains a low concentration of NaHCO 3 , the NaHCO 3The concentration is 10-15 mmol / L, preferably the NaHCO 3 The concentration is 12-13mmol / L.

[0018] In the present invention, the male-female ratio of wild broodstock of small grass carp in the breeding pond is 2 to 3:1, and the wild broodstock are self-fertilized to obtain fertilized eggs. As an practicable method, the self-fertilization in the present invention adopts the method of natural spawning and fertilization.

[0019] The present invention collects the fertilized eggs and transfers them into an incubation pool for incubation. The incubation conditions are: water temperature 20-28°C, NaHCO 3 The concentration is 5-10 mmol / L, the pH value is 7.5-8.2, and the dissolved oxygen is 5-8 mg / L; the water temperature is preferably 22-25°C, and the NaHCO 3 The concentration is preferably 7 to 8 mmol / L, the pH value is preferably 7.8 to 8, and the dissolved oxygen is preferably 7 to 8 mg / L.

[0020] In the present invention, the fertilized eggs are hatched to form the F1 generation. When the F1 generation is 1 to 2 cm in length, the F1 generation is transferred to a screening pool, wherein the water in the screening pool contains a high concentration of NaHCO 3 , the NaHCO 3 The concentration is 30-48 mmol / L, preferably the NaHCO 3 The concentration is 38-45 mmol / L. The present invention replaces F1 with a high concentration of NaHCO 3 The alkaline-resistant F1 generation is selected by screening in the water body, and the F1 generation that survives after 20 to 38 hours of culture is the alkaline-resistant F1 generation. The alkaline-resistant F1 generation is transferred to the culture pond for culture and used for the next generation of alkaline-resistant breeding. The water body of the culture pond contains low concentration of NaHCO 3 , the NaHCO 3 The concentration is 10-15 mmol / L, preferably the NaHCO 3 The concentration is 12-13mmol / L.

[0021] The daily breeding management of grass carp in Xiaohaizi in the specific embodiment of the present invention can be carried out by adopting the conventional management methods in the art.

[0022] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0023] Example 1

[0024] A breeding method for alkali-resistant grass carp, comprising the following steps:

[0025] During the breeding season of grass carp in Xiaohaizi, wild broodstock with gonad development to stage V were captured in Xiaohaizi Reservoir.

[0026] The captured wild broodstock are transferred to the breeding pond for breeding. The NaHCO in the water of the breeding pond is 3 The concentration is 10mmol / L, the female-to-male ratio of wild broodstock of small grass carp in the breeding pond is 2:1, and the wild broodstock are self-fertilized by natural spawning and fertilization.

[0027] The fertilized eggs were collected and transferred to the incubation pool for incubation. The incubation conditions were: water temperature 25°C, NaHCO 3 The concentration was 6mmol / L, pH value was 7.8, and dissolved oxygen was 6mg / L. The F1 generation was obtained after hatching.

[0028] When the F1 generation grows to 1-2 cm, the F1 generation is transferred to the screening pool. The NaHCO in the water of the screening pool 3 The concentration was 32mmol / L. After 30h of culture, the surviving F1 generation was the alkali-resistant F1 generation.

[0029] The alkaline-tolerant F1 generation was transferred to the culture pond for cultivation. The NaHCO in the water of the culture pond 3 The concentration is 10mmol / L and is used for the breeding of the next generation of alkali-resistant grass carp.

[0030] Alkali-resistant grass carp was obtained after four consecutive generations of breeding.

[0031] Example 2

[0032] A breeding method for alkali-resistant grass carp, comprising the following steps:

[0033] During the breeding season of grass carp in Xiaohaizi, wild broodstock with gonad development to stage V were captured in Xiaohaizi Reservoir.

[0034] The captured wild broodstock are transferred to the breeding pond for breeding. The NaHCO in the water of the breeding pond is 3 The concentration is 12mmol / L, the female-to-male ratio of wild broodstock of small grass carp in the breeding pond is 3:1, and the wild broodstock are self-fertilized by natural spawning and fertilization.

[0035] The fertilized eggs were collected and transferred to the incubation pool for incubation. The incubation conditions were: water temperature 23°C, NaHCO 3 The concentration was 8mmol / L, pH value was 8.2, and dissolved oxygen was 6mg / L. The F1 generation was obtained after hatching.

[0036] When the F1 generation grows to 1-2 cm, the F1 generation is transferred to the screening pool. The NaHCO in the water of the screening pool 3 The concentration was 42mmol / L. After 24h of culture, the surviving F1 generation was the alkali-resistant F1 generation.

[0037] The alkaline-tolerant F1 generation was transferred to the culture pond for cultivation. The NaHCO in the water of the culture pond 3 The concentration is 12mmol / L and is used for the breeding of the next generation of alkali-resistant grass carp.

[0038] Alkali-resistant grass carp was obtained after three consecutive generations of breeding.

[0039] Example 3

[0040] A breeding method for alkali-resistant grass carp, comprising the following steps:

[0041] During the breeding season of grass carp in Xiaohaizi, wild broodstock with gonad development to stage V were captured in Xiaohaizi Reservoir.

[0042] The captured wild broodstock are transferred to the breeding pond for breeding. The NaHCO in the water of the breeding pond is 3 The concentration is 14mmol / L, the female-to-male ratio of wild broodstock of small grass carp in the breeding pond is 3:1, and the wild broodstock are self-fertilized by natural spawning and fertilization.

[0043] The fertilized eggs were collected and transferred to the incubation pool for incubation. The incubation conditions were: water temperature 25°C, NaHCO 3 The concentration was 8mmol / L, pH value was 8, and dissolved oxygen was 6mg / L. After hatching, the F1 generation was obtained.

[0044] When the F1 generation grows to 1-2 cm, the F1 generation is transferred to the screening pool. The NaHCO in the water of the screening pool 3 The concentration was 48mmol / L. After 20h of culture, the surviving F1 generation was the alkali-resistant F1 generation.

[0045] The alkaline-tolerant F1 generation was transferred to the culture pond for cultivation. The NaHCO in the water of the culture pond 3 The concentration is 14mmol / L and is used for the breeding of the next generation of alkali-resistant grass carp.

[0046] Alkali-resistant grass carp was obtained after three consecutive generations of breeding.

[0047] Test Example 1

[0048] The half-lethal alkalinity of the alkali-resistant grass carp obtained in Implementations 1 to 3 was verified.

[0049] Methods: A total of 60 alkali-resistant grass carps were randomly divided into 6 groups and raised in water with alkalinity of 2g / L, 4g / L, 6g / L, 8g / L, 10g / L and 12g / L, respectively. The mortality of grass carps was observed and the half-lethal alkalinity (g / L) was calculated.

[0050] Results: The half-lethal alkalinity of alkali-resistant grass carp in Example 1 was 7.6 g / L, the half-lethal alkalinity of alkali-resistant grass carp in Example 2 was 8.4 g / L, and the half-lethal alkalinity of alkali-resistant grass carp in Example 3 was 7.8 g / L. It can be seen that the method provided by the present invention can effectively breed alkali-resistant grass carp.

[0051] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for breeding alkali-resistant grass carp, characterized in that: The steps include: Wild broodstock were captured during the breeding season of grass carp in Xiaohaizi, and self-fertilized in water containing low concentration of NaHCO3. Fertilized eggs were collected and transferred to hatching ponds, and the F1 generation was obtained after hatching. When the F1 generation grows to 1-2 cm, it is transferred into water containing high concentration of NaHCO3 to select the alkali-resistant F1 generation; the alkali-resistant F1 generation is transferred into water containing low concentration of NaHCO3 for cultivation and used for the next generation of alkali-resistant breeding; after continuous breeding for 3-4 generations, the alkali-resistant grass carp is obtained.

2. The breeding method according to claim 1, characterized in that: The NaHCO3 concentration in the water body containing low-concentration NaHCO3 is 10 to 15 mmol / L.

3. The breeding method according to claim 1, characterized in that: The NaHCO3 concentration in the water body containing high concentration of NaHCO3 is 30 to 48 mmol / L.

4. The breeding method according to claim 1, characterized in that: The hatching conditions of the fertilized eggs are: water temperature 20-28° C., NaHCO 3 concentration in the water body 5-10 mmol / L, pH value 7.5-8.2, and dissolved oxygen 5-8 mg / L.

5. The breeding method according to claim 1, characterized in that: The male-female ratio of the wild broodstock is 2 to 3:

1.

6. The breeding method according to claim 1, characterized in that: Wild broodstock are captured in Xiaohaizi Reservoir.

7. The breeding method according to claim 1, characterized in that: The gonads of wild grass carp broodstock in Xiaohaizi have developed to stage V.