On Sat, 19 Nov 1994, Jean-Pierre Chapleau wrote:
 
<deleted>
> bee pathologist signs an article confirming the resistance of varroa to Apista
n
 
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> I read with interest the the last issue of Apis.  The possible "revenge" of bu
gs
> and microorganisms we fight from our colonies is a big concern for me.   I thi
nk
> the TM approach of the AFB problem that prevails in north America is a
> dangerous.  I am convinced that it is possible to operate large commercial
> operation without TM.  I operate a commercial apiary (550 hives and 1400 matin
g
> nucs) since 1977 and I have never used the drug.  Yearly inspection of all the
> colonies, replacement of the combs every 4-6 years has been sufficient to keep
 a
> good control of the situation.  I also had to destroy or shake colonies
> occasionnally, but very few.  Less that one per year on average.   TM is
> dangerous since it only hides problems or potential problems.  Unfortunately,
> for most beekeepers who have been using TM for years, it is very difficult to
> stop using it.
 
In an ideal world, we could win a battle and it could stay won - but not
too often this world.
 
A most interesting subject.  I haven't finished with our previous
discussions (still wrapping bees), but I couldn't resist a word or two
(or more) on this. . .
 
Any victory tends to be temporary.  Drugs have provided a respite for
both bees and mammals, but there will always be a 'round two' etc. Rather
than to say 'the battle is ultimately doomed, so lets not try', I prefer
to look at the years of relief that drugs have given us, and look for
more similar advantages.
 
We can't rest on our laurels.  The pests don't.  The worst that can happen is
that we will revert to our status before drugs came on the scene.  The
best that can happen is that we may be able to extend our temporary
advantage.  After all, life is temporary.
 
Mankind has been able to lay a saddle on many organisms and befriend many
former foes.
 
We are unable to avoid the widespread movement of pests and parasites
without sacrificing communication and travel, and trade. Most of us
believe the advantages to us (humans and friends/allies) outweigh the
costs/risks.  As communication and travel get faster, the populations of
hosts increase in size and the potential for severe outbreaks of fatal
disease/infestation increases. *But* so does the pool of possible solutions.
 
I am not sure that, in the case of AFB, physically destroying any evidence
of a disease - that is obviously there everywhere in the background - is
much different from treating with drugs from a selection point of view -
unless one argues that the former selects for a more benign form of AFB
that does not cause breakdown or a variety of bees that is resistant to
the disease or both.
 
Drugs and other chemical controls may or may not be a stopgap measure
depending on whether - in a specific case - it is possible for the target
to develop resistance.  I don't think mammals are likely to develop
resistance to cyanide, for example.  The poison is too fundamentally and
drastically effective.  The problems occur where the target is similar to
the host such as in the case of mites and bees.  Effective chemicals have
to exploit obvious and permanent differences between the two.
 
In the case of pyrethroids, as far as I know, all cold blooded critters
find them toxic to varying degrees.  I am not sure of the mechanism, but
I gather when used on mites, the dosage is somewhat critical.  I know
from the following anecdote that bees are more resistant than house
flies. . . .
 
*       *       *       *       *       *       *       *       *
 
Several years ago (maybe more), we heard about the wonderful Alberta Bee
being developed at great expense up in Beaverlodge.  After much waiting,
at last queens were released for industry evaluation - ten or so at a
time.  We, of course ordered some and they arrived.  They were beautiful.
The attendants were robust and the queens were large.
 
I laid the qeen cages on the counter and watered them.  My wife was going
to use the queens shortly, so I left them face up.  I went back to my
bookwork.
 
There were a few particularly pesky flies in the building and one kept
landing on my bald spot.  I had to go out for a few moments, so, out of
habit, I took a can of Raid (a mixture of a pyrethroid and something
else) and laid down a cloud and went out.  On returning, I heard a
buzzing.  Ooops!
 
The flies were dead, alright - or in the final stages, but the bees
weren't looking too good either.
 
They did look much better than the flies, but not to take any chances, I
changed the attendants (which were more affected than the queens) and
used the queens - which seemed okay and apparently went on to do well.
 
*       *       *       *       *       *       *       *       *       *
 
Similar to pyrethroids, formic acid in excess would surely damage the
bees at some level not too far above the amount lethal to mites.
(Comments invited).  This is the problem.  I can see, without using too
much imagination, how a mite could evolve resistance to either of these,
seeing as we can't use enough to overkill by a large enough measure.
 
Tetracycline has problem too.  In a dose slightly higher than that
required to control AFB, (honeybee) larval mortality becomes a problem, I
understand.  Since the dose is critical - at least the window is fairly
narrow, we have the same problem.  We can't 'nuke' the offending organism
without damaging the host. Sulfa didn't seem to have the same problems, and
while available for the purpose, was much superior due to its
persistence.  Having a second, unrelated drug at hand, decreased the
chance of developing resistant strains of AFB considerably.
 
For any 'permanent' solution, we need controls - or a combination of
controls - that are so uniquely fatal to the target and benign to the
host, that there is no way that the target can adapt.
 
I read somewhere that pathology is the result of inconclusive negotiations
for symbiosis.
 
Of course the ideal solution is to encourage the mites to mutate to become
beneficial to the bees, while outcompeting the present strain.  And, since
Christmas is coming, it would be nice to have a strain of AFB that boosted
honey production.
 
What do you say, researchers - are we missing an opportunity? :)
 
Allen
 
W. Allen Dick, Beekeeper                      VE6CFK
Rural Route One, Swalwell,  Alberta  Canada  T0M 1Y0
Phone/Fax: 403 546 2588      Email: [log in to unmask]
 
PS I can see that I haven't thought this out as rigorously as I would
like, but I'll post it anyhow.  For discussion and derision. :)
 
Maybe it should be in a philosophical group like alt.atheism or such.
 
Later. . .