My respects to Andy the Great from whom I am learning considerably through
this net.
 
  I should like to share thoughts on using TM correctly. When I first saw this
abbreviation I thought it was referring to Transcendental Meditation but now
realise TM in this context means Terramycin, the commercial name of the
antibiotic oxytetracycline.
 
  Beekeepers are not allowed to use this in the UK.  The logic is that TM does
not eliminate foul brood, it only masks it. The entire contents of AFB hives
are burned in a pit and buried and the hive bodies are scorched with a blow
torch.  The same applies to EFB in many cases although in recent years
treatment by the Bee Diseases Inspector with TM if the infection is very light
is permissible.   It is interesting that although this chemical is cheaply
available in the US most commercial beekeepers destroy all AFB brood comb.
Why?
 
Andy notes that bees from different sources share their brood diseases when
brought together for pollination contracts.  This is our experience too and is
one of the reasons I don't play that game.  If I did, any honey and money
would come back but not the bees or their combs.
 
Andy also notes areas with AFB. In England there are areas which are notorious
for EFB.  They tend to follow gravel soils in river valleys and a link to a
lack of trace elements has been suggested.  However,  people build houses into
cities on poor soil because the land is cheaper.  They build roads along the
river valleys because it is flatter and easier.  Migratory beekeepers use
these roads to get to ling heather which also grows on poor soils.  AFB,
however does not seem particularly to be linked to area in the UK except
through contact colonies.  Can Andy explain please?
 
As Andy points out no EFB will BE FOUND when colonies are treated with TM.
This may be because EFB if present will be suppressed from multiplying to a
lethal dose; the lightly affected larva will before pupating void her faeces
(crap) around the cell.  The faeces will include viable bacteria which will
either be transferred to the cell cleaning bees before they become baby
feeding bees or will be pasted to the cell wall behind the old cocoon to
revive at an opportune time.  EFB is not spore forming so will not last for
ever but I understand it has a useful 'half-life' .  In the meantime the
beekeeper will have no idea that the combs are infected and will cheerfully
use them to set up a new colony.
 
I have been told by a geneticist,  (on this list I think) that resistance is
always present.  The trick is to avoid selecting for resistance.
 
One reason why AFB  is not so frequently found in wild bees may be wax moths
which do have their benefits.
 
Andy's penultimate paragraph is his most interesting.  He says that TM when
fed to NORMAL HEALTHY BEES (my emphasis) with no history of disease will
increase the amount of brood over feeding just sugar syrup alone.  Why should
this be?   The obvious answer is that "normal healthy bees" ain't too healthy.
Is that right, Andy?
 
It appears to me that unless the beekeeper KNOWS that his bees do not have
foul brood s/he must presume that they have it.  If TM is used then the
beekeeper will not know that the bees do not have foul brood.  The beekeeper
must therefore be most rigorous in apiary hygiene and comb renewal or one sort
of TM will be no more efficacious than the other in eliminating foul brood.
 
Having re - read the above I have just realised the error in my logic.  It is
not part of the plan of the makers/ sellers of TM to eliminate foul brood, if
fact they depend on its survival for part of their daily bread.
 
Sorry if this post is too long.  Its 2.15 am and I am too tired and inebriated
to be concise.
 
Chris Slade