Here it is - first the GOOD news , according to "the Fishician" Steve Pyecroft there have been no proven cases of TB transmission via eggs - the example I was trying to reroute around my Alzheimer's maze concerning the possible case in salmonids was pro
ven to be due to TB contaminated food fed to the fry. Theoretically there is a case for dipping the eggs in some sort of antiseptic to lessen the risk of pathogens on their outside.So breed them before you sacrifice them may be the way to go!
Now the BAD news.Apparently the Mycobacteria organisms are ubiquitous i.e. they are everywhere in the aquatic environment.....in nature as well as in our tanks.However mostly they go about their business in the organic substrate as non-pathogens. They mul
tiply in the presence of a high organic/acid detritus situations and so these situations not only stress our fish but also encourage a large supply of the potential pathogens.
Then something happens,and EITHER the organism becomes virulent enough to be infective/invasive and eventually contagious OR the host/fish has its normal immunity lowered by the stresses of the inappropriate environmental factors OR a combination of both
OR some other factors as yet unknown induces this change.
Apparently this virulence can be increased by repeated passage through a host especially if environmental conditions continue to be unfavourable. Given that the organism is everywhere perhaps we may have to rethink our ideas about getting breeders with a
reputation for Ulcer Disease to dispose of their stock. Perhaps we should be encouraging them to adopt better fish-keeping techniques.
As a corollary we should be able to buy fish from them, quarantine them in good conditions for a few weeks and if they are not showing any overt features of TB they may be OK , or at least not much more of a risk to our other fish than anybody elses.????
Suddenly there seems to be a ray of sunlight in all this gloom. By the way Steve will be going online soon and we can look forward to some first-hand contributions from him.
Bruce Hansen ANGFA(N+Q)