a b s t r a c t
Using standard epidemiological methods, this study set out to quantify the risk associated
with exposure to easily diagnosed factors on colony mortality and morbidity in three
migratory beekeeping operations. Fifty-six percent of all colonies monitored during the
10-month period died. The relative risk (RR) that a colony would die over the short term
(~50 days) was appreciably increased in colonies diagnosed with Idiopathic Brood Disease
Syndrome (IBDS), a condition where brood of different ages appear molten on the bottom
of cells (RR = 3.2), or with a "queen event" (e.g., evidence of queen replacement or failure;
RR = 3.1). We also found that several risk factors -- including the incidence of a poor brood
pattern, chalkbood (CB), deformed wing virus (DWV), sacbrood virus (SBV), and exceeding
the threshold of 5 Varroa mites per 100 bees -- were differentially expressed in different
beekeeping operations. Further, we found that a diagnosis of several factors were significantly
more or less likely to be associated with a simultaneous diagnosis of another risk
factor. These finding support the growing consensus that the causes of colony mortality are
multiple and interrelated.
excerpts for review purposes only:
> We monitored Idiopathic Brood Disease Syndrome (IBDS), a syndrome first described by Shimanuki et al. (1994), but renamed here because its underlying cause it yet unknown.
NOTE: This is a reference to Shimanuki, H., Calderone, N.W., Knox, D.A., 1994. Parasitic mite syndrome: the symptoms. Am. Bee J. 134, 827–828.
> Unfortunately, the underlying causes of these conditions are poorly understood, and our findings suggest that previous assumptions -- such as the putative role of Varroa mites in IBDS -- may be incorrect.
Idiopathic brood disease syndrome and queen events as precursors of colony mortality in migratory beekeeping operations in the eastern United States. Dennis vanEngelsdorp, et al, in: Preventive Veterinary Medicine. Copyright © 2012 Elsevier B.V. All rights reserved
***********************************************
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
|