> I have given plenty of evidence that it [Fumagillin] is not [effective].
> "Although overwintering treatment had no
> significant effects on N. ceranae intensity,
> mortality was significantly higher in colonies
> wintered outdoors. This, coupled with an
> insignificant relationship between fall
> N. ceranae intensity and colony mortality,
> supports data that N. ceranae may not
> always pose the most significant threat to
> western honey bees."
> Williams PhD Thesis 2013
But the next sentence in the thesis, the line chosen as the closing
summation of the entire thesis, is far more important to this discussion
than the lines quoted. It offers a very plausible explanation for the
results described in the quote above:
"We can only speculate, but it is possible that N. ceranae present in
Maritime Canada differs in virulence from strains found in other regions of
the world, or that experimental colonies were not sufficiently stressed, and
therefore not particularly susceptible to N. ceranae disease. More work is
needed to investigate damaging thresholds of N. ceranae..." (page 54)
So, even the author of this thesis himself clearly concedes that N. ceranae
is a virulent problem elsewhere, and feels that the issue needs more
investigation. It is important to note that he chose not to make any firm
conclusion, but instead ended his thesis saying that the local N. ceranae
"differs in virulence". It would misrepresent the intent of the author to
offer his words as proof of something he clearly disavows.
The above-quoted thesis is here:
http://dalspace.library.dal.ca/bitstream/handle/10222/21716/Williams-Geoffre
y-PhD-BIOL-March-2013.pdf
or
http://tinyurl.com/o7mspwe
Reading through, the researchers worked Nova Scotia, PEI, and New Brunswick.
I am not at all surprised that overwintering colonies indoors swamped out
all other survival factors there.
The thesis itself also states that each of its major chapters were published
as separate papers in peer-reviewed journals, but those papers included far
more qualification and equivocation about the issues we are currently
discussing here than the subject thesis, which is to be expected, as a
thesis is not reviewed with the same level of scrutiny as a published paper.
In contrast, we have a quick post from Dr. Medhat Nasr (linked below). As
Alberta has a harsher winter than the Maritimes, his comments are apt, and
of interest, as they are in stark contrast to the findings offered by the
thesis from the Maritimes.
http://community.lsoft.com/scripts/wa-LSOFTDONATIONS.exe?A2=BEE-L;b56b0b0a.1
309
or
http://tinyurl.com/qxwrokn
Also, from what Medhat says in his post linked above, the claims of
persistence of these antibiotics seem highly speculative at this point, even
to a 10ppb limit of detection.
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