Still, given the awesome
fecundity of koi, their natural reproduction in a pond is not as
commonly encountered by koi hobbyists as should be. The
primary reason for this is that koi love eating their eggs and
larvae. As such, their young seldom grow big enough for a pond
owner to see. People who want to produce their own koi fry,
therefore, can not rely simply on natural reproduction in the pond.
To increase their success in producing koi fry, they need to mimic
the natural reproduction of koi under more controlled conditions
using the basic method for breeding koi.
One disadvantage of this old
method for breeding koi is its dependence on the cooperation of the
koi being bred, i.e., the female must be induced by the male to lay
eggs and the male should be able to fertilize these eggs.
A more dependable method for
koi production is known as the dry method of fertilization. This
method induces the female and male koi to release their eggs and
sperms, respectively, through 'hand-stripping' under dry conditions (which is
how it got its name). The steps employed for the dry method of
koi fertilization are as follows:
1.
Collection of the Female's
Eggs. Put the
ripe and ready-to-spawn female koi in a small container that's filled with a tranquilizing solution (e.g., 100 ppm Benzocaine). The transfer must be made very gently using a
soft net since the koi is heavy and can be easily injured out of the water.
The tranquilizing solution anesthesizes the female koi.
Once
it is calm enough, take it out of the water carefully and
wipe it gently with a soft towel until it is dry (see Figure 1). The
female koi must be dry prior to being stripped of its eggs because
the eggs will pre-activate if it comes into contact with water
before they are fertilized.
A helper
must clog the genitals of the koi to prevent it from releasing eggs
prematurely during this procedure.
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Figure 1.
Prior to hand-stripping, the koi must first be dried
with a clean and soft cloth. |
After the koi has been dried,
it is ready for hand-stripping. To do this, gently massage and squeeze the swollen belly
of the koi while holding it over a dry, clean bowl. The gentle
squeezing will cause the female koi to release its eggs in the form
of a brownish fluid, so make sure that when this happens the fluid
will fall directly into the bowl to avoid spillage (see Figure 2).
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Figure 2.
Collect the eggs of the female koi in a dry, clean bowl
during hand-stripping. |
