excellent  question Peter!

>What does spore count mean?

About the same as counting varroa. Simply an indicator because many of the
highest infested bees are dying in the field nosema . In commercial
operations its simply not cost effective to test each hive.
Researchers with a test group can but still the best advice for commercial
has been to treat all hives in the bee yard rather than on a hive by hive
basis.

Is higher bad?

Some hives can handle higher nosema loads but*in my opinion* not forever.
First its a few hives and then half the hives with high spore counts. Spore
counts can rise and drop.  Can take a few seasons before you see hives with
hive threatening infestations.

What I see is infestations continue to rise rather than mysteriously go
away.

other problems can make the hive more susceptible to nosema. The top being a
high varroa load.

In general when you see millions of spores in many samples you *in my
opinion* need to treat.>


>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.

the above word *healthier* is the issue. jerry Brumenshenk asked when he
first looked at CCD in California we need to establish what is the standard
for a healthy hive.

its not the dinks only which end up drowning in feeders and unable to take
syrup. I have seen hives appear healthy in my former nosema test yard one
week and in the feeders the next.

Its true hives dwindle. why wouldn't they as foragers are dropping fast with
high infestations but prolific queens can at times keep up with the loss
giving  the appearance no nosema problem. However when the honey flow is
over and the queen slows way down the hive rapidly drops.

commercial migratory beekeepers see the swings more than researchers using
hives being maintained on precise syrup feedings and with little stress.

Advertisements for fumagilin has long claimed bees with high nosema
infestations die around two weeks earlier than bees not infested. Also look
at the honey loss from forager bees dying a couple weeks early.

 Usually happens in Missouri in August. The really healthy hives maintains
size (or drops slightly) ands the nosema ceranae infested hive starts
dwindling.

I agree with Juanse there is a point when the hive needs depopulated ,
deadout worked and fresh bees added once the bees will not take syrup. *If*
the bees are taking syrup then you can turn the situation but you still have
to deal with the spores as all fumagilin does if treat the active disease.

5 years ago researchers said the nosema ceranae spores on comb would not
cause problems but I think many now believe eliminating the spores on
deadouts is worth the effort.

I have little time to pull up research backing each statement but research
is available which both supports and most likely research which does not
agree with the above.

I read a huge amount of research as do others on the list. certainly not as 
much as my friend Peter.

Bob Harrison

beekeeper
no Phd's by my name

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