Previous

Next



4@What the fish mating experiment aimed at

The present experiment is a preparatory one for the future 
Medaka experiments in Space Station. The IML-2 Medaka 
experiment proved that mating, laying eggs and embryonic 
development are all possible in space. These results showed 
the possibility of the multi-generation breeding of this 
fish in Space Station, where a long-term experiment can be 
planned. The primary objective of Medaka space experiments 
is to obtain the fundamental data for the future realization 
of fish culture in space.

1. Objectives of IML-2 Medaka experiment

   This particular space experiment was planned 
in order to obtain fundamental data and to 
present some idea on designing the aquaculture 
(fish culture) style in space. The following 
special themes were investigated using the fish 
Medaka in the Shuttle flight of 2-week duration.
 1)Whether fish can carry out mating behavior 
and lay eggs or not under microgravity (Mating 
and laying eggs), 2)When eggs are laid through 
mating in space, whether all the processes from 
fertilization to hatching (coming out as a baby 
fish) take place normally or not under 
microgravity (Embryonic development), and 
3)Letting the space-flown fish continue to mate 
and lay eggs on the ground after the space mission,   
whether any effects can be detected or not on 
their descendants (Effects on offspring).
   Beside these, in this mission, I tried to solve
one important problem for the multi-generation 
studies of this fish in Space Station Alpha. In 
the IML-2 experiment, inside the aquarium for the 
adult fish, a place for eggs they laid and fry, 
not for the adult fish, was set (two-generation 
aquarium). Thus, checking whether this separation 
mechanism works or not in space was also one of 
the objectives of the present experiment, the 
result of which may be useful for designing the 
new aquatic animal experiment unit, possibly used 
in JEM (Japanese Experiment Module) in the Space 
Station.

2. A long-range objective of the Medaka 
experiment  -- Fundamental studies for 
fish culture in space

   Aquaculture (fish culture) in space will be 
important protein resources when human start to 
stay and live in space. Especially, Japan is good 
at making a variety of processed food from fish meat, 
and such techniques may be useful also in future 
space life. However, at present there is not any 
precise image yet of fish culture in space. 

Previous

Next


|28|


Back to Contents Back to SpaceMedaka Homepage