Bayvarol

[Alastair]

Just thought I would put some info out there about Bayvarol now it is becoming regarded as less reliable.

Couple of seasons ago I had a big fail with bayvarol, a lot of hives it didn't work and I had to go around and re treat with apivar.

However I was left with around 7 grands worth of bayvarol, too much to throw away so took advice from Tristan and others here and waited a while and then try it again.

So I used it in hives this autumn and just done some checking today. Very pleased with the results . I did not run any mite tests, but any PMS that was starting to show in a few hives when I placed the treatment has cleared up and all hives were looking good. No hives showed any signs of mites at all, so I'm confident this treatment will be a success.

Looks like it will work if you give the hives a rest from it for a while.

 

[tristan]

resistance management.
trouble is resistance comes back quickly, the mutation hasn't disappeared totally.

of course the big question is how long before we get resistance to apivar?

 

[Alastair]

of course the big question is how long before we get resistance to apivar?

Could be anytime, they have it in the US now.

Course, over there the standard treatment used by commercials for many years has been a paper towel soaked in Tactik, which is a cattle drench that contains amitraz. By doing that they can treat the hive for a few cents instead of the cost of apivar.

BUT, this means hives are way overdosed for a few days and then get nothing. It may well be this abuse that has brought about their issues. Good thing this has not been widespread in NZ.

 

[JohnF]

Looks like it will work if you give the hives a rest from it for a while.

Yes - but its longer than a couple of seasons. Recent reports from the USA show that their varroa still harbour the resistance mutations years after stopping pyrethroid treatment. One of the reasons for this may be the sub-lethal levels of pyrethroids in the wax and frames (bee bread) that was found and that is essentially selecting for resistance.
Resistance to amitraz (apivar/apitraz) is caused by 1 of two mutations in a different gene - the receptor for amitraz.

I agree Alastair, NZ's use of commercial products - and good alternating practices - is the main reason why we have avoided widespread resistance

 

[tristan]

I agree Alastair, NZ's use of commercial products - and good alternating practices - is the main reason why we have avoided widespread resistance

i think its more down to use of commercial products that dose over long time periods rather than the one shot treatments (which require multiple shots) with homemade treatments.
plus keeping it out of SI for as long as they could.

alternating practises where non-existent for a long time, under dosing was common and we did get some resistance. fortunately that was a good wakeup call and practises improved from that.

 

[JohnF]

fortunately that was a good wakeup call and practises improved from that.

. . or not? In last year's colony loss survey it was something like 40% of beekeepers treating for varroa were under-dosing. Myths like cutting strip in half and other random off-label practices still seem to exist

 

[tristan]

. . or not? In last year's colony loss survey it was something like 40% of beekeepers treating for varroa were under-dosing. Myths like cutting strip in half and other random off-label practices still seem to exist

yes, since the price crash many have resorted to the old dodgy practises and inventing new bad practices. they will most likely pay the price as we know what the outcome is.
i'm surprised anyone would admit to it.

also i did mention things got better, 40% under dosing is still better which is sad.

 

[JohnF]

I agree that the current times put pressure on the ability to treat - but I know these practices have been going on longer than the market downturn. Also, that 40% is an *improvement* has to be speculation Tristan - at least at a national level.
A lot of the reasons for doing so are not purely financial but from long-held interpretations of early information and data about what the strips contained. Plus an unhealthy dose of urban myth . . .

 

[Alastair]

My own experience is the more money I spend on treatment, the more money I make.

Or conversely, most of my attempts to save money on treatment have been more expensive in the long run.

 

[tristan]

I agree that the current times put pressure on the ability to treat - but I know these practices have been going on longer than the market downturn. Also, that 40% is an *improvement* has to be speculation Tristan - at least at a national level.
A lot of the reasons for doing so are not purely financial but from long-held interpretations of early information and data about what the strips contained. Plus an unhealthy dose of urban myth . . .

yes its somewhat speculative. i can only gauge by what i see.
but there certainly was a decent change when resistance first hit, that really spooked a lot of beeks.

yes the using scientific testing as an excuse to under dose is still an issue, including reusing strips due to other research. any reason to outsmart themselves.