Page 46 - Koi Net - On-Line Koi Magazine - Issue 94

quarantining any new additions to your pond. The stress
DO YOU NEED TO
QUARANTINE KOI? SIX WEEKS
Mark Davis, Cuttlebrook Koi Farm. IS A MINIMUM
PERIOD FOR
QUARANTINING
The word ‘quarantine’ (which, incidentally, comes from
the Latin quarantine, meaning ‘forty days’), is a length NEW KOI
of time in which a disease can be incubated, and
therefore expressed in an organism. That way, it’s
possible to see who does, and doesn’t, carry a specific
disease. Traditionally, forty days is the time that many
major diseases will incubate in humans, but the
situation for fish is a little different, and our view of
what quarantine means for them is something of a
‘grey area’.
Mark Davis. Wherever you source your Koi from, always quarantine
them before introducing them to your pond. It’s a
question of ‘best practice’ and however much you trust
the honesty of your supplier, and however good they
say their bio-security is, it is your personal responsibility
to ensure the welfare of your existing population of fish,
not theirs, and if they make a mistake and compromise
their bio-security, by quarantining any new Koi you can
help to make sure it isn’t you that pays for that mistake.
Fish suffer from diseases just like any other animal – it’s
part of nature that they do and you can’t get away from
it. Of course, you can do a lot to ensure that they stay
healthy but, just occasionally, they are bound to fall
victim to some kind of parasite, viral or bacterial
problem. You can reduce the risk of them being
exposed to any of these problems in the first place by
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of moving to a new home can lead to a reduction in the
effectiveness of a Koi’s immune system and during this
vulnerable time, any number of common diseases can
take advantage of that and trigger a health problem for
your new Koi.
For this reason, a tank which is completely separate
from your main pond, with its own filtration, bowl and
net and ideally with the ability to be heated, will provide
an environment that allows you to monitor your new Koi
closely and respond to any problems that may arise. Six
weeks is a minimum period for quarantining Koi and
should provide enough time for any underlying bacterial
or parasite problems to become apparent.
During that time it is also recommended that the Koi be
heat cycled in order to try and find out if your new Koi
may have been exposed to, and might therefore be
carriers of, Koi Herpes Virus (KHV). KHV, which is deadly
to most Koi and which can remain dormant in any
surviving Koi, is active at between 18 and 27 degrees
Centigrade and Koi should be taken from a temperature
lower than 18 degrees to, for example, 23 degrees and
held at that temperature for two weeks – that’s how
long it can take a Koi exposed to the virus to show
symptoms.
After that time the cycle should be repeated if possible.
This heat ramping is not absolutely guaranteed to bring
out the virus but it is the best method yet discovered of
doing so. Once your Koi have successfully completed
their quarantine period, they can be introduced to your
pond with the confidence that you have done everything
possible to ensure the health of all your Koi.
In the next issue of Koi Net, Mark Davis will be
taking an in-depth look at quarantining your Koi.
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