hi to all
sorry if I insert myself into the discussion. but let me know if you did a calculation on the cost of treatments for the control of nosema!
I would give my two cents of experience,
years ago I spoke of problems with Nosema ceranae here in Sardinia on this list.personally have tried to find a solution for our climatic conditions. We initially tested several control products, thymol, fumidil, apiherb, and a product of Bayer which is not currently remember the name. we performed this research for two years, and in different parts of Italy. the result of our investigation was that if in the hives sample (without treatment) there was a rise in natural spores of nosema, no product had asufficient efficacy, the fumagillin was the product that had a greater effect, (not higher than 70% ) but shortly afterwards the spores rapidly increasing. however, if the hivessample had a natural decrease of spores, all the products worked, ... of course withdifferent levels of effectiveness! the product more effectively, was the fumagillin (over 90%) but it worked very well in the formulation of thymol Ryce. I can not quantify in moles, but we utilizzavammo 36 g thymol dissolved in alcoll for 600 kg of sugar. This experience led to a nosema see how a disease that depends critically important to the sensitivity of .I can not quantify in moles, but we use 36 grams of thymol dissolved in alcoll for 600kg of sugar. This experience led to a nosema see how a disease that depends critically important to the sensitivity of the race of bees and the conditions of the season. because the conditions of the season are not predictable, we started toremove all the small hives in the fall, and also delete all hives that had signs ofdisease in spring, trying to multiply all the hives that came from the winter in excellent condition. so looking to widen the main weapon of defense of bees, in my opinionbiodiversity.
We have had major losses initially, but with sterilization by gamma rays and the frames with the self-production of packages of bees in a short time we managed to recover losses. for now we are very satisfied and they do not we spend more money on treatments that allow even sensitive nosema bees to survive.
currently follow more than 3000 hives 
sorry my bad english but I'm doing online help from a translator.  ( http://translate.google.it/#auto|it| )
thanks
 Giuseppe caboni
strada prov 4 km 12
09026
San Sperate (ca)
www.apimed.com


Il giorno 08/mar/2012, alle ore 20:49, Peter L Borst ha scritto:

> What does spore count mean? Is higher bad? Here they show higher counts in the healthier bees, implying that they are better able to tolerate nosema whereas bees in the susceptible lines are already dead.
> 
>> After artificial infections of the N. ceranae spores, the lineage selected for Nosema tolerance showed a higher N. ceranae spore load, a lower mortality and an up-regulated immune response. 
> 
> Survival and immune response of drones of a Nosemosis tolerant honey bee strain towards N. ceranae infections
> Qiang Huanga , Per Kryger, Yves Le Conte, Robin F.A. Moritz
> 
>             ***********************************************
> 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


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