> To my surprise, I often find few or no mites in the drone brood of my trap frames. Following that: "Examination of drone brood? Not viable for diagnosing varroosis" Our results showed that it is not possible to calculate the size of the varroa population parasitising a colony simply by examining the infestation rate of drone brood. This is probably influenced in part by the cycles of drone brood production in each colony and in part by the cyclical nature of the infestation of cells by varroa. The parasite load of drone cells was seen to vary from one- to six- times in the space of a week, without any relation to the actual varroa population. This confirms the observations of Ritter & Ruttner who also observed the weakness of the infestation of drone brood as a measure of colony infestation. From: "The removal of capped drone brood: an effective means of reducing the infestation of varroa in honey bee colonies" JEAN-DANIEL CHARRIÈRE, et al. Bee World 84(3): 117–124 (2003) © IBRA *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html Guidelines for posting to BEE-L can be found at: http://honeybeeworld.com/bee-l/guidelines.htm