Hi Murray,
 
In message <[log in to unmask]>, Murray McGregor
<[log in to unmask]> writes
>In article <[log in to unmask]>, CSlade777 <[log in to unmask]>
>writes
>>As I understand it having attended a lecture from Dr Watkins at the National
>>Honey Show last November,  the chemical is the same (fluvalinate) in both
>>Apistan and Bayvarol but the method of delivery is subtly different as the
>>different plastic strips used do not allow the fluvalinate molecules to arrive
>>at the surface at the same rate.
>> My apologies to Dr Watkins if I have misunderstood and also for trying to
>>encompass part of a long and fascinating lecture in a single sentence.
>>Chris Slade
>
>
>Apistan's active ingredient is fluvalinate.
>Bayvarol's active ingredient is flumethrin.
>
>Not EXACTLY identical substances but VERY closely related, which is why,
>I am led to believe, that resistance trials in USA show resistance
>developing to both substances stemming from exposure only to
>fluvalinate.
>
Yes, true. The original work was done by Dr Norberto Milani at Udine
University in Italy in 1994. He showed a clear cross resistance between
pyrethroids in varroa treatment. Varroa mites that had developed
resistance to tau-fluvalinate were [are] also resistant to flumethrin
and to acrinathrin. Therefore products based on thes molecules cannot be
used as rotation partners to reduce resistance levels where pyrethroid
resistance is already shown.
 
Sorry if that's a bit long-winded. But it is!
 
 
All the best,
 
 
Max
 
>Murray
>--
>Murray McGregor
>[log in to unmask]
 
--
Dr Max Watkins