Principles of Genetics and Breeding

5.1.1.1 Combining traits of different species

E.g., Silver carp (Hypophthalmichthys molitrix) x bighead carp hybrid (Aristichthysnobilitrix).

• The hybrid showed higher survival and yield than parental species. This hybrid was commercially cultured in Israel during 1970s to 1980s.
• The specific aim was to produce a fish that is able to utilize both phytoplankton (as the silver carp) and zooplankton (as the bighead carp). The pores of the filtering apparatus of the hybrid are intermediate in size between those of the parent species.
• As a result the hybrid is able to filter both kinds of plankton but the phytoplankton consist of the larger colonial types.
• The hybrid therefore cannot prevent massive blooms of micro algae, such as the blue green algae, which prevention is often the main function of silver carp.