> Those look to the sellers of bee equipment for answers such as (only a few but many many more )

I am sorry but the fact that people are selling products and other people are buying them is simply not proof that the products are good nor that they work. I have talked about fumagillin with many beekeepers who use it and many who don't. Nobody knows whether it provides real benefit. And there is a mountain of evidence that it does not and that it is not needed. 

Nosema apis (Zander) is generally considered
to be mostly harmless for Apis mellifera. However,
relatively little is known about the virulence
of Nosema ceranae or the impact of this species
on honey bee population dynamics (Fries, 1996).
Forty and 78 bee hives, located in Bonn (2000)
and Bochum (2008 and 2009), Germany, respectively,
were monitored regarding their colony development
(Liebefeld method) and their infection
with Nosema ceranae. In our honey bee colonies
in Western Germany, the distribution pattern of
the two Nosema species clearly shifted from 2000
(100% N. apis) to 2009 (March 2008: 10% N.
apis; March 2009: 100% N. ceranae). In contrast
to N. apis, N. ceranae did not show a characteristic
seasonal progression of the proportion of infected
colonies or bees. Neither the individual bees’ degree
of infection with N. ceranae nor the mean quantity
of spores found per colony correlated with the daily
loss of adult bees. Thus, we could not detect a pronounced
pathogenicity of N. ceranae or find a beneficial
effect of the daily bee loss. In contrast to previous
studies, the year-round infection with Nosema
ceranae did not affect the development of the observed
honey bee colonies in this field study.

Association of Institutes for Bee Research
Report of the 57th Seminar in Bochum
23–25 March 2010

             ***********************************************
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