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CN-121970723-A - Method for inducing grass carp triploid based on two-stage temperature-control hydrostatic treatment

CN121970723ACN 121970723 ACN121970723 ACN 121970723ACN-121970723-A

Abstract

The invention relates to the technical field of fish genetic breeding, in particular to a method for inducing triploid of grass carp based on two-stage temperature-control hydrostatic pressure treatment. The invention focuses on the application of the hydrostatic pressure treatment method in the induction of the triploid of the grass carp under the condition of two-stage temperature control, and explores a high-efficiency induction method. Through a system experiment, the influence of key parameters such as treatment time, pressure intensity, duration and the like on the induction rate of the triploid of the grass carp is deeply analyzed under the condition of two-stage temperature control, and the optimal induction condition is determined. The result shows that the two-stage temperature control method can obtain the triploid induction rate of 96.58 percent, and meets the requirement of mass production of triploids. In addition, the research discovers that the grass carp triploid has the advantages of accelerating growth performance, improving meat quality and the like, and provides powerful technical support for grass carp genetic breeding and sustainable development of aquaculture industry.

Inventors

  • ZHENG GUODONG
  • ZOU SHUMING
  • YUAN ZIMING
  • YANG ZIQUAN
  • GUO ZAOZAO
  • ZHANG HUIMEI
  • JIN YANG
  • YU HAOYU

Assignees

  • 上海海洋大学

Dates

Publication Date
20260505
Application Date
20260313

Claims (8)

  1. 1. The method for inducing the triploid of the grass carp based on the two-stage temperature-control hydrostatic treatment is characterized by comprising the following steps of: artificial insemination, namely selecting female grass carp and male grass carp as propagation parents, respectively obtaining sperms and ova, and then carrying out artificial insemination to obtain fertilized ova; Hydrostatic treatment, namely hydrostatic treating fertilized eggs in 2.5 to 3.5 minutes after fertilization, wherein the hydrostatic treatment temperature is 17.5 to 18.5 ℃, the pressure is 35 to 45MPa, and the duration is 3 minutes; And (3) after the hydrostatic pressure treatment is finished, transferring the fertilized eggs to an environment with the water temperature of 25.5-26.5 ℃ for hatching.
  2. 2. The method of claim 1, wherein the hydrostatic treatment water temperature is 18 ℃ and the incubation water temperature is 26 ℃.
  3. 3. The method of claim 1, wherein the fertilized egg is subjected to hydrostatic pressure 3 minutes after fertilization.
  4. 4. The method of claim 1, wherein the hydrostatic treatment has a pressure of 40 MPa.
  5. 5. The method of claim 1, wherein the water temperature is controlled to be 17.5-18.5 ℃ in the whole artificial dry insemination process, and the dissolved oxygen amount of the water body is controlled to be more than or equal to 6 mg/L.
  6. 6. The method of claim 1, wherein the ovum is obtained by extrusion.
  7. 7. A method according to any one of claims 1to 3, wherein the method induces a triploid grass carp having a length of foregut villi greater than that of a diploid grass carp and having a muscle with a higher crude protein and/or crude fat content than that of the diploid grass carp.
  8. 8. The method according to claim 1, wherein the triploid grass carp has a chromosome number of 72 and a karyotype of 3n=33m+33sm+6st.

Description

Method for inducing grass carp triploid based on two-stage temperature-control hydrostatic treatment Technical Field The invention relates to the technical field of fish genetic breeding, in particular to a method for inducing triploid of grass carp based on two-stage temperature-control hydrostatic pressure treatment. Background Grass carp (Ctenopharyngodon Idella) is used as a core member of four-big family fish in the freshwater aquaculture industry, and takes a key position in the freshwater aquaculture field by virtue of the remarkable biological characteristics of high growth rate, excellent meat quality, strong environmental tolerance and the like. The industrial scale and the industrial influence of the grass carp in the freshwater aquaculture industry are highlighted, and the economic value of the grass carp as a core aquaculture variety is highlighted. However, there are a series of ecological and management problems in the grass carp farming process that need to be solved. Under the traditional high-density cultivation mode, grass carp escape phenomena are frequently generated, and if scientific management and control are lacked, the population quantity is extremely easy to grow in a runaway manner, so that serious threat is formed to an aquatic ecosystem. Researches prove that excessive propagation of grass carp can damage the community structure of aquatic plants, reduce the transparency of water body and finally cause unbalance of aquatic ecosystem. Specifically, the degradation of aquatic vegetation can directly weaken zooplankton biomass, and further the population size of filter-feeding fishes such as silver carp (Hypophthalmichthys molitrix) and bighead carp (ARISTICHTHYS NOBILIS) which eat plankton is obviously reduced. Meanwhile, the high-density cultivation can cause problems of reduced growth rate of grass carp, frequent occurrence of diseases and the like, thereby restricting sustainable development of grass carp cultivation industry and causing obvious lower economic benefit. Therefore, a scientific management strategy which combines ecological protection and cultivation benefits needs to be constructed so as to realize dynamic balance of grass carp cultivation and aquatic ecosystems. Under the background, the technology of manually inducing triploid provides a scientific path for solving the difficult problem of grass carp cultivation. The triploid grass carp has reproductive sterility, so that the natural reproduction process of the triploid grass carp can be effectively blocked, the damage to aquatic plant resources is obviously reduced, and the stability of an aquatic ecosystem is further maintained. Even if escape occurs in the cultivation process, the sterile characteristic of the plant can avoid gene pollution or ecological interference to natural population. Since the 50 s of the 20 th century, polyploid induction technology has been widely used in the field of fish genetic breeding, and students at home and abroad successfully induced triploid in various fishes such as carp (Cyprinus carpio), megalobrama amblycephala (M. amblycephala), rainbow trout (Oncorhynchus mykiss), crucian carp (Crucian carp) and the like, and have remarkable achievements. The main induction methods currently include temperature shock, hydrostatic and chemical induction. The chemical method is limited in application due to the possible environmental risk and food safety problem caused by drug residues, and the temperature shock method is simple and convenient to operate, but has large damage to fertilized eggs, low survival rate and difficult large-scale popularization. In contrast, hydrostatic pressure is receiving great attention because of the advantages of easy standardization of the treatment procedure, small damage to fertilized eggs, higher induction rate, etc. For example, in the prior art, it was found that when a pressure of 7000 PSI (about 48.26 MPa) or 8000 PSI (about 55.16 MPa) was applied 4 minutes after fertilization, the triploid rate of 9 groups in 10 experiments exceeded 98%, but the hatching rate was only 69.1% on average. As can be seen, current research on hydrostatic pressure induced triploid grass carp is still relatively limited. In view of the above, it is highly desirable to provide a new method for inducing triploid of grass carp, which can comprehensively consider the hatching rate and the induction rate. Disclosure of Invention In order to solve the problems, the invention provides a method for inducing triploid of grass carp based on two-stage temperature-control hydrostatic treatment. The invention is realized by the following technical scheme: A method for inducing triploid of grass carp based on two-stage temperature-control hydrostatic treatment comprises the following steps: artificial insemination, namely selecting female grass carp and male grass carp as propagation parents, respectively obtaining sperms and ova, and then carrying out artificial insemination to obt