Re: [RML] Dark half or quarter on rainbowfish

David Wilson (rwilson at taunet.net.au)
Thu, 31 Dec 1998 18:54:27 +0930

Is it related to the nervous system or
>>mycobacteriosis? The colour pattern on the sooty grunter went away after a
>>few days.
>
>This is the answer I got from Stephen Pyecroft re this problem I had with
>some rainbowfishes (these fish showed the darkening colour on one side of
>the body only): Trifasciata seem to be particularly prone to this problem.
>
> "As we have discussed before, the dark areas on the skin are most likely
>due to a malfunctioning in either the pigment cells or the nerves that
>control the pigment cells in that area of the skin. The findings of a
>generalised infection with Mycobacterium sp. would be suggestive that the
>localisation of the dark pigmentation is due to the formation of local
>abscesses, which are then causing the expression of the major clinical sign.
>Most of these cases of "blackhead syndrome" in rainbowfish that I have
>investigated have had a primary infection with Mycobacterium sp."

Adrian.

Thanks for that answer,(I missed the earlier discussion) next time the
sooty grunter gets the dark quarter (for id purposes) I'll catch it out and
sent it to Berrimah Animal Research Centre and ask them to check for
mycobacteriosis. We had confirmed mycobacteriosis in one aquarium about
three years ago so I sterilised it and everything nearby. Will let you
know results.

Regards
Dave Wilson