Chierism in native fish species as a tool for surrogate propagation in aquaculture

• Grant number: 12/14257-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2012
• End date: August 31, 2013
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: George Shigueki Yasui
• Grantee: Isabella Malachias Gaspar
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated research grant: 10/17429-1 - Chimerism in native fish species as a tool for surrogate propagation in aquaculture, AP.JP

Abstract

Chimerism is a phenomenon in which the cells from a donor individual may coexist with other individuals. The transplantation of primordial germ cells (PGC) from a donor individual to a host gives rise to a germline chimera. The resultant individuals from such transplantation may produce heterologous gametes, that is, host organisms of germ cells producing gametes from the donor species. This fact is interesting for aquaculture because species presenting easy reproductive management may be used to produce gametes from other species. Although such technology is feasible and may increase aquacultural production, initially it is necessary to clarify several aspects regarding basic biology before achieving the production of germline chimeras. Therefore, we aim with this study to produce germline chimeras for surrogate production in aquaculture, using annual spawners as donor species and intertidal spawners as hosts, and then producing offspring over the year. This study has two distinct stages. During the first stage (basic), protocols of micromanipulation and blastomere transplantation will be obtained, including egg dechlorination, a detailed description of early developmental stages, and traceability of primordial germ cells. During this stage, we will also develop techniques for sterilization of host species by triploidization. The second stage related to the production of germline chimeras will consist of the transplantation of cells from donor species to sterile triploid host, followed by confirmation of germline transmission by means of histological observations, flow cytometry, and progeny test. We will also develop protocols for cryopreservation of PGC by vitrification, that will be used to obtain germline chimeras. From the technologies developed in this project, we expect to generate an alternative procedure to improve fingerling availability for fish farming.(AU)