Reasonable thinking, but perhaps not the most appropriate time periods:
 
   the "varroa protected in the brood cell" period is not the same as the
   full developmental time for a drone. The period from when a varroa mite
   enters a cell shortly before capping, until the host bee emerges, is
   maybe 13 days for workers, 16 days for drones.
   So a 45 day treatment covers more than 3 cycles for workers, and well
   over 2 cycles for drones.
 
   I expect that several other factors (fluvalinate diffusing to wax, etc)
   were considered when the treatment period recommendation was being
   decided.
 
 
   Kerry Clark, Apiculture Specialist
   B.C. Ministry of Agriculture
   1201 103 Ave
   Dawson Creek B.C.
        V1G 4J2  CANADA          Tel (604) 784-2225     fax (604) 784-2299
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