> > Tom's suggestion of adding a frame of open drone brood to queen rearing
 > > colonies should solve the problem of Varroa infestation...

 > Well, ready for sealing drone brood might not offer much of a window for the
 > mites to enter the cells prior to sealing....

This all seems to be a lot of bother.  What's wrong with adding an Apistan Strip
if in doubt?  Or using bulk bees that had Apistan treatment?

One does not normally produce honey on cell builders or nucs, so almost any
treatment that kills v-mites and does not affect cell building should be okay.

allen
-----
See if your questions have been answered in over a decade of discussions.
BEE-L archives & more: http://www.internode.net/HoneyBee/Bee-l.htm
Search sci.agriculture.beekeeping at http://www.deja.com/
or visit http://www.internode.net/HoneyBee to access both on the same page.