European eel is a catadromous fish species, which means that
after living in freshwater premature individuals
adapt to sea water, and migrate to the Sargasso Sea for
spawning. Although male eel can be
sexually matured even in freshwater, up to date, it was believed
that female eel can be matured only in
seawater. Here we show that the process of sexual maturation may
be induced in freshwater by treating
female eels with carp pituitary (GSI = 9.87±1.55%). It is thus
proposed that seawater condition is not an
obligatory environment for stimulating gametogenesis and for
artificial maturation of the European eel in
neither gender.