>Would you post the link, please, Randy?
Certainly!

Cousin M, Silva-Zacarin E, Kretzschmar A, El Maataoui M, Brunet J-L, et al.
(2013) Size Changes in Honey Bee Larvae Oenocytes Induced by Exposure to
Paraquat at Very Low Concentrations. PLoS ONE 8(5): e65693.
doi:10.1371/journal.pone.0065693
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0065693
And thank you Jim for the lesson on statistics, to which I gladly defer to
you.

So help me out here Jim and Christine.  I'm looking at supportive Data S3.
It appears to me that there are very large hive-to-hive, and larva-to-larva
differences in RNA expression, independent of treatment.  This gives me
pause.  Am I wrong in suspecting that the differences are due to something
other than treatment, and might not similar differences possibly confound
the analysis?

What really surprises me about this study is that such a strong effect was
claimed for differential gene expression in larvae, when in studies in
which transmission of pesticide residues to larvae via jelly has been
measured, the pesticide is virtually eliminated during conversion from
beebread to jelly.  So there is really no telling as to whether the larvae
were actually even exposed to the chemical.  However, it is perhaps
plausible that the nurse bees changed the composition of the jelly, and
that such a change affected larval gene expression.  But then we again are
starting to stretch.

Couple this with the fact that imidacloprid is virtually nontoxic to bee
larvae, it greatly surprises me that by feeding a tiny amount of
imidacloprid (100mL of 2 ppb IMI in syrup per day, which would be only a
tiny fraction of that consumed by a colony on say canola) that such a
strong effect would be noticed in the larvae in this trial.

Had the researchers followed a protocol such as that in the paper cited
above, in which the larvae all came from the same colony, and would thus
have had the same background exposure to plant allelochemicals and
pesticides, and had then fed the treatment to the nurse bees in cages to
account for any elimination of the chemical in the normal process of larval
feeding, then I would certainly accept any findings without question.


-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

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