>Hi, > >Can anyone give me a journal(s) reference(s) for research into the minimum >infective doses for European Foul Brood and American Foul Brood. > Refer to Bee World: Vol. 74, No. 4, page 177, review article by Ratnieks "20 spores constitute an LD50 for one-day old larva, whereas millions of=20 spores are necessary to infect a 4-5 day old larva". Marion Ellis, [log in to unmask]