Bacteria are able to aquire new genes in a variety of
ways. When discussing the use of tetracycline grease
patties, it does not matter how the resistant strains
developed rather that they now exist.

Improper use of antibiotics keeps constant selection
pressure on the bacteria so that the resistant strains
will predominate.  Allowing a time of reproduction
without this selection pressure will enable the
bacteria to continue to change genetically and enable
a mixture of strains to exist.  The the most suitable
strain will become the predominant type.  (Survival of
the fittest).  Likely there will be a mixture of
strains.  This can in time weaken the resistant strain
and decrease its prevelance.

Ideally in an integrated pest management situation,
you only use a pesticide or antibiotic when needed -
not prophylactically.  In some instances, it may be
impractical or impossible to measure the level of
infestation and prophylactic measures may be all that
is available.  Proper use of both antibiotics and
pesticides will lengthen their life and reduce
residues in the foods that we consume.  Leaving
Apistan strips and tetracycline grease patties in your
hives all the time is very irresponsible and hurts
everyone.

Hopefully with the constant selection pressure of
varroa on honeybees, tolerant strains will survive and
reestablish a strong feral bee population.  Russian
Queens may bring to us a genetic mechanism for
tolerance.  Let's keep our fingers crossed.  We may be
able to use less antibiotics and pesticides in
beekeeping in the future.

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