Contributions of Genetics to Freshwater Aquaculture in Asia

Despite its important role in providing livelihood for people in Asia, aquaculture has received only minor benefits from the implementation of genetic improvement programmes. Several strains of freshwater fish have been developed mainly by farmers with limited knowledge of genetic principles. This has led to the genetic deterioration of many of the farmers' stocks. Recently, a few genetically improved strains have been developed through implementation of genetic concepts. Novel strains of tilapia and rohu have been developed by selection, while cross breeding is more commonly used in common carp. The interspecific hybrid between the Thai walking catfish and the introduced African catfish has almost completely replaced the native catfish in aquaculture in Thailand. The prospect of implementing genetics for freshwater aquaculture development in Asia and considerations regarding genetic threats on aquatic biodiversity caused by aquaculture stocks are discussed in this article.