Good points, Jim!
Have entertained several of them myself.

The taxonomic confusion for N ceranae was obvious at the American Bee
Research Conference.  I can't find my notes at the moment, but we were
presented with two different taxonomic trees by two different researchers.

Re: side by side light microscopy comparisons, I've been searching for N
apis samples to view.  Although the samples that I've had tested all come
out as ceranae by PCR, the spore morphology is extremely variable under the
scope.  Some skinny, some wide, some larger, some smaller, some not always
oval.  Varies within samples, and especially from colony to colony.  I'm
certainly not sure that I'm always looking at the same species.

As I've mentioned earlier, the colony-to-colony difference in reaction to
nosema infection is striking!  Since all my test colonies are in the same
yard, nutritional effects are not likely.  Plus they likely have all been
exposed to the same nosema(s), by drift and robbing of deadouts.

I would expect differences in resistance in colonies on a genetic basis. But
my test yard was stocked solely with colonies that had high nosema counts
last fall, so I would consider them all to be susceptible to the parasite.

So the question is, why do some colonies appear to be thriving with high
counts (this has also been reported to me by others), while other colonies
collapse.  I strongly suspect one or more pathogens in concert with nosema
(whatever its taxonomy) at work.

Randy Oliver
Two more swarms from recovering nosema-infected colonies the last two days.

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