Varroa resistant to Thymol

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just had our AGM lecture, on Varroa control and developmnets

Found it rather worrying in that several cases of Varroa that are not dropping if thymol is given at the normal tines

one hive treated with thymol crystals was dropping on 5 mites but when looked at by summer bee inspector was deemed to be "wing damagel possible high varroa" so trearted with apistan and dropped 2000 on first day

its since been ememgency treated with oxalic( despite having brrod)vand drooped anther 2000

the summer bee inspector said when asked that cases of this have been reported at St albans, North Herts, Cambridge and now us in north Barnet as resistant to thymol, and thymol patties, (the propriatory thymol gell was implied to be even worse )

one aparie 3 miles away of 20 hive was angain treated and deemed, thymol resistant, and those hive are overseen by an ex bee inspector

anyone else heard of thymol resistance varroa
 
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i have heard of people having problems with thymol for a few months but is it not just a single part of some ones treatment package or do people only use it on its own

these had oxalic in jan/feb, drone brood removed spring ( by super frame in brood box) and thymol cystals, open mesh floor and sugared twice

apert from apistan what else can be done..? kill first brood, but then in london, some hive lay brood very early

we were adivised by our BKA not to use apistan as local vaorroa mainly resistant

summer inspector also saif that two new varroa products may be approve by june
 
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Could this be due to the extended brood season this year?
When you think that Thymol starts to max out around 85% kill rate then with the extended brood rearing we have had this year it would give some hives a good chance of Varroa levels building up again.

There are some new products to treat Varroa due to the market in 2010,lets hope its not the companies selling these products that are causing the jungle drums to sound.
 
Could this be due to the extended brood season this year?
When you think that Thymol starts to max out around 85% kill rate then with the extended brood rearing we have had this year it would give some hives a good chance of Varroa levels building up again.

There are some new products to treat Varroa due to the market in 2010,lets hope its not the companies selling these products that are causing the jungle drums to sound.

Long autum ,dont think so, the first hive with resistance was found in july by the summer inspector oa we had EFB in north barnet and all other hive sites were checked
 
So where will we find the official papers on thymol resistant varroa,any links. Use formic,if thymol is not doing anything.
 
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it has been suugested that essentail oil such as Tea Tree or Manuka oil in the sugar feed kill Varroa, has anyone tried it?

Tried Tea tree oil last year. No other treatments. My colonies are still alive.

I think whatever you use, whether chemical or essential oil, the important thing is to vary treatments .
 
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So where will we find the official papers on thymol resistant varroa,any links. Use formic,if thymol is not doing anything.


this was purely report back,i have no links, the talk was mainly about EFB as a communal apairy had an out break of EFB, all member hive were looked at in july/august due to possible cross contamination by members

the varroa was at one out aprairy just by the M25, 20 hives all hives had been treated the same, five had heavy varroa but no drop with thymol.

i know nothing more than a statement that that the be inspector said that she had seen it at st albans ( 10miles) and cambridge 25miles and that they were investgiating..they took bee samples

the first hive was a new beek who had a Nuc from the M25 sitee but lived miles away, also had the thymol no drop varroa
 
Long autum ,dont think so, the first hive with resistance was found in july by the summer inspector oa we had EFB in north barnet and all other hive sites were checked
What accredited method was used to identify resistivity ?.
Sounds anecdotal to me !. thymol requires careful administration ,taking weather conditions into consideration , ventilation restrictions etc. the cool wet Summer probably had more influence on the efficacy of the treatment than any resistant mites..

John Wilkinson
 
What accredited method was used to identify resistivity ?.
Sounds anecdotal to me !. thymol requires careful administration ,taking weather conditions into consideration , ventilation restrictions etc. the cool wet Summer probably had more influence on the efficacy of the treatment than any resistant mites..

John Wilkinson

i have no more than i have given already, its not my apiary

but you could be right, could just be inclement weather during application, and the fact that its hives at our non town location we use for OSR in spring and all the association other site are microclimate town sites

what works in town, does not work in the country
 
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I have not seen reports about varroa resistancy to thymol. Surely reseachers let beekeepers to know if that exists.

Thymol needs high temperture to be effective and surely ventilation issues.
It is same with formic acid.
 
Resistance wouldn't surprise me. I heard 2nd hand the other day that an eminant scientist said that in a couple of years the best choice of varroa treatment would be to take a packet of each one on the market, throw them into the air and catch one and use it.

There is very little the average beekeeper can do to check for resistance prior to use, so you will have to hope for the best as Varroa appear to be able to adapt themselves to the chemicals we use.
 
Apart from doing a simple resistance test,which every beekeeper should know how to do.

Which is what makes one wonder about this imformation,when pyrethroid-resistant varroa mites were found originally not far enough away from where i am,and very shortly after at another spot,the news travelled like wildfire,and bee inspectors were testing bee's all over the country,and issuing resistance test kits.
And formic has been used for over thirty years,never heard of any resistance to that.
 
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My bet for varroa is that someone will develop a varroa pheremone which you will locate under the hive and it will atract the mites away from the bees.
 
Taken from the Apiguard site,

"However, the development of resistant varroa mites through using Apiguard is unlikely. Thymol disrupts the biological processes of the mite, with
multi-site action on cell membranes and the nervous system, unlike traditional chemical acaricides, which target one specific site on the nervous
system. Resistance to thymol is much less likely to develop because of this."

From the Thymomite site,

"Resistance: There are no published reports of the resistance of Varroa to Thymol."

I know these site might be bias but it would be good to see a link to the published papers so they could be corrected.

Mike.
 
I remember reading a paper that showed 6 different recepters in the mite that were targeted by Thymol,I would not expect mites to be able to get around all 6 modes of action.
 
If the thymol kills all the mites that are exposed to it then none are left to breed; however if a few do survive then by definition they must have some sort of resistance which could be passed on to their offspring.

I understand that thymol efficacy is not 100% - may be as low as 90%. Are there survivors because the thymol didn't kill them, or because they weren't exposed to it?

Paul
 
Because they were not exposed to it,even bavarol ect would not kill all the mites in a hive.Like those horror films,always one little monster survives.
 
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