Seed production method of super-male nile tilapia mossambica

Abstract

The invention discloses a method for breeding super-male tilapia nilotica, which belongs to the field of fishery breeding, and comprises the following steps: carrying out critical temperature breeding on primary tilapia nilotica young seedlings to promote sex reversal of the tilapia nilotica young seedlings, and breeding the first filial generation F1 of the survival young seedlings into adult fishes, the method comprises the following steps: screening a sex-reversed XY-female tilapia population from female individuals in adult fishes through molecular markers, independently breeding the screened XY-female tilapia population, and then hybridizing the XY-female tilapia population with XY of a population with stable genetic sex to obtain a first filial generation F2. According to the technical scheme, the XY-reversed Nile tilapia population with temperature control reversal is screened to be hybridized with the common XY-reversed Nile tilapia population to obtain the super-male Nile tilapia offspring, so that the use step of a female inducer is omitted, the risk of possible environmental pollution is reduced, and the food safety and the ecological safety are improved.

Description

Technical Field

[0001] The invention belongs to the field of fishery breeding, and in particular relates to a method for producing super male Nile tilapia seeds. Background Art

[0002] In terms of the comparison between male tilapia and female Nile tilapia, male tilapia grow faster than female tilapia. Female tilapia reaches sexual maturity at 130 days and can reproduce multiple times during the culture period, which seriously limits the growth of female fish, resulting in a large number of different batches of tilapia competing for dissolved oxygen, nutrients and space in the pond, and the newly bred tilapia fry in the pond cannot grow into commercial specifications at the end of the year. Mixed breeding of males and females greatly affects the output and benefits of tilapia farming. Therefore, commercial large-scale production of all-male fish is the goal of tilapia breeding at home and abroad.

[0003] Existing breeding methods are generally divided into two categories. The first category is to use male hormones to treat fish fry to induce so-called all-male male fish, which will seriously affect consumer health and the ecological environment. The second category is the MAS-GMT technology (such as CN101406165B), the first step of which is to induce sex reversal of XY individuals, that is, to cultivate XY transformed female fish (XY♀), which still requires the use of estrogen, cannot completely avoid pollution, and is time-consuming and labor-intensive. Summary of the invention

[0004] In order to solve the problem of using sex hormones in breeding, the present invention aims to provide a natural method for producing super male Nile tilapia seeds.

[0005] In order to achieve the above object, the technical scheme of the present invention is as follows: A method for producing super male Nile tilapia comprises the steps of: subjecting primary generation Nile tilapia roe to critical temperature culture, and surviving roe to produce the next generation F 1 The natural XY♀ Nile tilapia population was screened by molecular markers, the screened XY♀ Nile tilapia population was cultured separately, and then the XY♀ Nile tilapia population was hybridized with the XY♂ population of genetically stable sex to obtain the first generation F 2 .

[0006] Further, the method further comprises the following steps:

[0007] S1, put Nile tilapia roe F in the culture pond 0 , then the culture temperature of Nile tilapia roe fry was controlled at 40°C;

[0008] S2, regularly clean the living environment of the surviving fry in the breeding pond. 0 When entering the breeding season, lower the water temperature to 25°C;

[0009] S3, the offspring F 1The natural XY♀ population of Nile tilapia was screened by molecular markers, and the F1 was then cultured separately. During the culture process, the culture pond was divided into 0.12m 3 Form an independent slot;

[0010] S4, then the XY♀ population of Nile tilapia was crossed with the XY♂ population of genetically sex-stable population to obtain the F 2 Thus, super male Nile tilapia is obtained.

[0011] Furthermore, while lowering the water temperature in S2, the water volume in the breeding pond is reduced to two-thirds of the initial value.

[0012] Furthermore, the breeding capacity of each independent cutting slot in S3 is within 6 fish.

[0013] The following beneficial effects are achieved by adopting the above scheme: 1. Compared with the prior art of female induction in CN101406165B, the present technical scheme screens a natural XY♀ Nile tilapia population for super-masculinization hybridization to obtain super-male Nile tilapia offspring, thereby omitting the step of using a female inducer, reducing the risk of possible environmental pollution, and improving food safety and ecological safety.

[0014] 2. Compared with the existing technology of artificial screening, the present technical solution utilizes the natural sex reversal of Nile tilapia affected by environmental factors, so as to increase the male rate of Nile tilapia by high temperature breeding, thereby increasing the proportion of male Nile tilapia in the F1 generation, and then screening the feminized XY♀ Nile tilapia population among male Nile tilapia during the breeding process, so as to improve the screening process in a specific population and save labor.

[0015] 3. This technical solution uses a separate breeding method to reduce the possibility of fish fry loss caused by fighting between parent fish. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The following is further described in detail through specific implementation methods:

[0018] The embodiment is basically as shown in the attached Figure 1 As shown: A method for producing super male Nile tilapia seeds comprises: subjecting primary generation Nile tilapia roe to critical temperature culture, and surviving roe to produce the next generation F 1 The natural XY♀ Nile tilapia population was screened by molecular markers, the screened XY♀ Nile tilapia population was cultured separately, and then the XY♀ Nile tilapia population was hybridized with the XY♂ population of genetically stable sex to obtain the first generation F 2。

[0019] The following steps are also included:

[0020] S1, putting Nile tilapia roe F0 into the culture pond, and then controlling the culture temperature of Nile tilapia roe at 40°C;

[0021] S2, regularly clean the living environment of the surviving fry in the breeding pond. 0 When the breeding season comes, the water temperature is lowered to 25°C. When the water temperature is lowered in S2, the water volume in the breeding pond is reduced to two-thirds of the initial volume.

[0022] S3, the offspring F 1 The natural XY♀ population of Nile tilapia was screened by molecular markers, and the F1 was then cultured separately. During the culture process, the culture pond was divided into 0.12m 3 An independent grid is formed, and the breeding capacity of each independent grid in S3 is within 6 fish;

[0023] S4, then the XY♀ population of Nile tilapia was crossed with the XY♂ population of genetically sex-stable population to obtain the F 2 Thus, super male Nile tilapia is obtained.

[0024] In the technical solution, natural XY♀ Nile tilapia populations are screened for supermasculinization hybridization, thereby saving the step of using female inducers and reducing the risks of environmental pollution, food safety and ecological safety.

[0025] Subsequently, the natural sex reversal of Nile tilapia is affected by environmental factors, so high-temperature breeding is used to increase the male rate of Nile tilapia, thereby increasing the proportion of male Nile tilapia in the F1 generation. Subsequently, the feminized XY♀ Nile tilapia population among male Nile tilapia is screened during the breeding process to improve the screening process in a specific population and save labor.

[0026] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0027] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for producing super male Nile tilapia, characterized in that: The method comprises subjecting the first generation of Nile tilapia roe to critical temperature culture to induce sex reversal of the Nile tilapia roe, screening the sex-reversed XY♀ Nile tilapia population through molecular markers when producing the next generation F1 from the surviving roe, breeding the screened XY♀ Nile tilapia population separately, and subsequently hybridizing the XY♀ Nile tilapia population with the XY♂ population of genetically sex-stable population to obtain the next generation F2.

2. A method for producing super male Nile tilapia seeds according to claim 1, characterized in that: The following steps are also included: S1, the cultivation of the first generation of fry, Nile tilapia roe F0 is put into the cultivation pond, and then the cultivation temperature of Nile tilapia roe is controlled at 40°C; S2, the second generation of fry, regularly cleans the living environment of the surviving fry in the breeding pond. If F0 enters the breeding period, the water temperature is lowered to 25℃ to generate the first generation F1; S3, screening of Nile tilapia, the F1 generation produced by breeding is screened by molecular markers for natural XY♀ Nile tilapia population, and then the F1 is cultured separately. During the culture process, the culture pond is divided into 0.12m 3 Form an independent slot; S4, breeding of super male Nile tilapia, followed by hybridization of the XY♀ Nile tilapia population with the XY♂ population of genetically sex-stable population to obtain the F2 generation to obtain super male Nile tilapia.

3. A method for producing super male Nile tilapia seeds according to claim 2, characterized in that: In S2, while lowering the water temperature, the water volume in the breeding pond is reduced to two-thirds of the initial level.

4. A method for producing super male Nile tilapia seeds according to claim 3, characterized in that: The breeding capacity of each independent cutting slot in S3 is within 6 fish.

Images