>Could you help? Yesterday I noticed our mature male Trifasciata (Arnhem
>Ck) with a dark patch at a third of his body (tail end), on one side only,
>and only above the center black stripe. Then last night the last 1/4" of
>his black stripe, just before his tail fin, started loosing colour. On
>close look of that part, the scales are still quite shiny.
>
>About six months ago we had a female Incisis that lost the colour on the
>second half of its body, infact it looked as if the bacteria had eaten away
>her scales! She caught the disease and deteriorated very quickly (within
>few days). We had to freeze her as she was starting to smell!
>
>I fear that the Trifasciata could have the same thing. What do you think?
>What can we do?
This is one of many similar questions I receive all the time through email
from people all around the globe and in person, so I perceive this problem
to be fairly common with rainbowfishes.
Well, I just had confirmed today that once again we find TB to be the
culprit. I have had three such specimens showing the dark skin
discolouration only on one side of the head and a fourth specimen showing
black discolouration on the rear half of one side of its body tested and the
results show acid-fast bacteria to be present that has affected the neural
pathways which control the skin colouration.
I might add that the fish in question did not show any other visible signs
of disease or stress, they were eating well and generally looks quite
healthy. I just wanted to know what was causing the discolouration.
I don't have the full results in hand at the moment so cant give you more
details. However, to me it only confirms what I said earlier about TB being
a major problem, particularly with rainbowfishes. This along with the
well-known symptoms of mycobacteria and many of the more unusual symptoms
will, if tested, prove to be caused by mycobacteria infection.
Steve Prycroft (Fish Vet) advised me that he received some Goyder River tris
last week with the same black patches on one side of the head and they
tested positive to mycobacteria infection as well.
Adrian.
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Adrian R. Tappin
"Home of the Rainbowfish"
http://www.ecn.net.au/~atappin/home.htm
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