Re: [RML] Dark half or quarter on rainbowfish

Gary Lange (gwlange at stlnet.com)
Sat, 2 Jan 1999 08:06:11 -1000

Bruce, who was it that had sent a message to our list earlier saying that
they had seen mycobacterium like ulcers in wild caught fish? Somehow I had
it in my mind that it was you but your comments below sound like that isn't
the case. I thought that someone had even had the disease confirmed by
microscopic examination.

I'm especially interested in hearing David Wilson's comments about finding
ulcers on rainbows in the wild, (in the Northern Territory) especially the
trifasciata. It seems like fish, like the Goyder River tri can get it quite
easily. Other rainbows in the tank never show symptoms their entire lives.

I would bet that with a little bit of serious looking you will find that
there also are rainbows in the wild that have TB and that it does occur
there naturally. I think that in the wild you don't have as many stress
points as you do in the aquaria however and you don't see the disease in
epidemic proportions as you sometimes can in our fishtanks.

gary lange

-----Original Message-----
From: Bruce Hansen <bhansen at ozemail.com.au>
To: rainbowfish at pcug.org.au <rainbowfish at pcug.org.au>
Date: Friday, January 01, 1999 4:47 PM
Subject: Re: [RML] Dark half or quarter on rainbowfish

>I am unaware if any work has been done on the distribution of naturally
>occurring Mycobacteria species in Australian aquatic habitats as opposed to
>commercial/wholesale/retail/hobbyist situations but my guess is that
>Australian native fishes would have evolved resistance to the naturally
>occurring species from their own habitat to alllow that species of fish to
>survive. Also the conditions existing in nature probably favour existence
of
>the TB bug as a saprophyte rather than a pathogen also environmental
>conditions for the fish would tend to favour being in good condition to
>resist becoming infected.
>
>It would be nice David if you could check at Berrimah if they have any
>records of TB from the wild in native fishes.
>
>
>Regards,
>Bruce.
>
>Bruce Hansen, A.N.G.F.A., Advancing Australian Aquatics.
>
>Bruce Hansen, ANGFA, caring for our aquatic ecosystems.
>
>Please visit us at http://www.ozemail.com.au/~fisher/angfa.htm
>
>
>-----Original Message-----
>From: David Wilson <rwilson at taunet.net.au>
>To: rainbowfish at pcug.org.au <rainbowfish at pcug.org.au>
>Date: Saturday, 2 January 1999 8:02
>Subject: Re: [RML] Dark half or quarter on rainbowfish
>
>
>
>>>> >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.
>>
>