>A friend of mine had problems with lesions (read TB) in his tri's about 6
>or 7 years ago ( before it was fashionable ;-) ). He swore that it was
>worse at higher temperatures (above 27 degrees Celcius) , and also that
>maintaining the general hardness higher assisted in keeping the disease at
>bay.
I have heard about hardness of the water before however, there is no
evidence to support it in any scientific literature. Also this bacterium is
very common in saltwater. This is another reason we need to confirm
mycobacteria infections and the conditions under which the fishes were being
maintained at the time of infection. I have read every bit of information
that I can find on mycobacteria. In fact it is probably becoming an
obsession :-)
This is an interesting tit bit that I found. I'm not sure where I found it
but I think it was on some University site. (Pemberton Trout hatchery is in
NSW - I think?)
Piscine mycobacteriosis is a systemic chronic progressive bacterial disease,
which presents varying clinical signs depending on the conditions. The
disease may take several years to develop from an asymptomatic state to
clinical illness. It is the most commonly reported mycobacterial isolate
from tropical freshwater and marine fish. Since 1988 Pemberton Trout
hatchery has had sporadic positive tests for M. marinum in the kidneys of
fish. Attempts to locate the source of infection are ongoing but are
hampered by lack of information on the biology of the organism, and most
especially by the lack of a reliable, cheap and fast method for detection of
the bacterium. The objective of this project is to develop a PCR based
method for detection of the bacterium. PCR methodology including a list of
possible primers for M. marinum have been described. The test would allow us
to screen asymptomatic hatchery fish for the bacterium so that we could work
out how the infections are occurring, and to determine the prevalence of the
bacterium in the fish.
The project would involve: testing primers to determine those that are
specific, testing sensitivity of primers, optimisation of methods for DNA
extraction from blood, culturing of bacteria from blood, screening hatchery
fish. In collaboration with Dr Brian Jones, Ag WA fisheries.
Adrian.
Adrian R. Tappin
"Home of the Rainbowfish"
http://www.ecn.net.au/~atappin/home.htm