The recent comments from down under (where, incidentally, my son the master
beekeeper is currently training and sailing in catamaran races) have caused me
to give AFB some thought, as does the recent emergence of the realisation that
the oxytet resistant AFB that has cropped up in Canada and the US may be
actually IMPORTED and not home grown as previously assumed.

I must hasten to point out for those who doubt the value of reading BEE-L that
the appearance of oxytet resistant AFB in North America and this obvious
possible cause was first (AFAIK) predicted here on this very list quite a long
time back by this very scribe, who also pointed out at that time, that
Argentinean honey from resistant AFB areas in South America was finding its way
unrestricted into both countries -- as well as the fact that honey is known to
carry AFB spores and the fact that honey is known to sometimes be discarded into
open landfill sites by householders.

I wonder what the eventual outcome will be.  I have heard that increased doses
of oxytet do, in fact, manage the outbreaks in Canada, although burning has also
been used.  (More info please, anyone).  I have also previously reported that
IMO, the doses of oxytet that most north American authorities recommend have
been only borderline effective and that higher doses have been necessary with
the garden variety AFB for the 25 years or so that I have known the disease,
some of them as an inspector.

I also want to mention that I think that the reason that AFB has otherwise
recently become less of a problem to reasonably good beekeepers in North America
is thanks to the vampire mites.  It is, indeed, an ill wind that blows no good,
and we can see easily that the mites have eliminated the worst beekeepers, ones
that were likely most responsible for maintaining reservoirs of the disease.

Moreover, and maybe more importantly, the advent of mites has caused increased
attention to scientific selection in bee breeding.  Although hygienic behaviour
has not been proven to have a large impact on mite resistance by bees, it is one
of the few relatively simple and obvious things we have that we know does some
good, so in the past ten years the idea of testing breeders for hygienic
behaviour has gone from a fringe idea, promulgated by ST and his fans to a
mainstream concept.  No self respecting bee breeder nowadays would admit openly
to NOT testing for hygienic characteristics, even if some of the methods used
are pretty Mickey Mouse.   As a result, all the bees out there in the common
gene pool are becoming more hygienic.

I don't know if Steve was exaggerating when he claimed that he could develop an
AFB resistant bee in a few generations -- anytime he wanted to -- by using this
test, but I suspect that we have -- as a result of our attempts at dealing with
mites -- done so to varying degrees.

I also tend to think that although the Aussies and the Kiwis have bees that are
pretty AFB resistant because these operators (are supposed to) burn both hive
and bees anytime they find any AFB.  This removes the most susceptible stock
immediately and over time increases resistance.  I wouldn't be surprised if many
of their breeders are using the hygienic test now too.   I have related
previously how I installed Aussie bees onto 48 doubles of very contaminated
equipment in spring 98 (no apparent scale though) and treated them only once
with a grease patty in a one year span.  One year later a frame by frame
inspection revealed zero AFB.  Good bees IMO.  That's how it should be.

My guess if that if all breeders keep using the hygienic screening properly in
time, we will see a vast decrease in AFB to the point where it requires very
little attention.  There are other factors, such as susceptibility of brood to
infection, but early removal by bees of any potential further contamination in
the form of infected larvae is a giant step.

allen
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