> Gabon tapes contain acrinathrin which is very closely related to
> tau- fluvalinate, the active ingredient in Apistan/Mavrik/Klartan
> and to flumethrin, the active ingredient in Bayvarol and Bayticol.
> It is proven that there is a cross-resistance in varroa to all three
> substances. This means that if there are pyrethoid resistant mites,
> Gabon will be no more effective than Apistan or Bayvarol.
 
Varroa will probably develope resistance to all pyrethroids. It's
probably  matter of time. But as I know, the tests  - so far -
showed that varroa resistant to Apistan was not resistant to Gabon.
Not yet.
 
Talking about relationship of pyrethroids (your statement
'acrinathrin which is very closely related to tau- fluvalinate' can
be discussed...) is simillar to talking about relationship between
antibiotics. It does exist bacterias which are resistant to some
antibiotics and so far not to others. So far we can't say if some
bacteria is resistant to one antibiotic, it's resistant to all of
them. So far.
 
When talking pyrethroids relationsship you must think that Gabon is
- let say  - a 'second generation' of pyrethroids.
 
Take for example a look at the dosage for one beehive (mentioned
before):
Apistan: around 1000 mg (different in different countries )
Gabon: 0,1 mg
 
I even mentioned before - toxicity for bee/varroa
fluvalinate: 2x
acrinathrine: 200x
 
Lot of people are concerned about residues (when talking pyrethroids -
in wax which can be present in honey ).
 
LD50/man
fluvalinate (Apistan ): 250 g
acrinathrine (Gabon ): 280 g
(compare with salt (NaCl) - 200g )
 
ADI/man (Acceptable Dayly Intake ):
fluvalinate: 7 mg
acrinathrine: 1,4 mg
 
NOEL /man (NO Effect Level ):
fluvalinate: 70 mg
acrinathrine: 210 mg
 
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