Garth said
 
>Hence one should have a period  when the total number of spores in the >hive will decrease dramatically as they are lapped up by cleaners and killed >with TM when they germinate.
 
The key words here "when they germinate".  We know that TM will not kill spores so to completely rid a hive of AFB spores, every spore in the hive must be exposed to the TM when they germinate.  If this is not the case then you still have AFB in the hive and it will still self perpetuate in the hive.
 
> In the end, a number of the bacteria will develop TM resistance. To
> do this they will probably have hauled water from a puddle with a Cow  
> pat in it. Cows are fed TM and harbour hundreds of TM resistant
> strans.
 
As I understand it, the TM may have been exposed to that bacteria in the cow but it will not be AFB unless cows get AFB.  In reverse, I don't think that the bacteria in cows cause disease in bees.  So, as it has been explained to me, the resistance comes, not from a common water source, but continued low level exposure to the anitbiotic.  There is also not cross resistance to diseases in other animals that are fed a common antibiotic.
 
With regard to the resistance question, I seem to recall reading in an American Bee Journal or Bee Culture several years back that AFB in Russia was showing signs of resistance to oxytetracycline hydrochloride.
 
If our Editors are on line to Bee-L, maybe they can recall this or check in past issues as there has been no mention of this case in Russian since, that I have seen.
 
Trevor Weatherhead
AUSTRALIA