Immature Varroa Mites?

[B+.]

Ooops...I posted before reading your link
I think I'm saying much the same as your article does

 

[charlievictorbravo]

I haven't treated my bees since the early 1990's. Around 1993 or 1994 if memory serves me right.

VSH involves the ability to detect infected cells AND the ability to uncap/remove the infected larva. Its more than damage to the carapace. When the USDA did this early work, they found all colonies had it to an extent. They had to select for it over the generations to intensify the trait. I think Marla Spivak wrote some papers about it but I don't have them to hand.

The Arista group were able to find the same trait in a test which was conducted with Buckfasts last year and will be conducting a similar test on Carniolans this year.http://aristabeeresearch.org/

In your experience, do the two elements of VSH always go together - bees chewing mites and bees uncapping infected brood cells - or can they exist as separate traits. Do some just chew and others uncap or is it always done by the bees in combination?

CVB

 

[B+.]

In your experience, do the two elements of VSH always go together - bees chewing mites and bees uncapping infected brood cells - or can they exist as separate traits. Do some just chew and others uncap or is it always done by the bees in combination?

CVB

I have definitely observed varroa on the sticky board with damaged carapace. I have also observed nymphs in various conditions - some damaged and some intact. However, I have not observed what I would call true VSH in my colonies. The reason I say that is the test involves freeze-killing a section of brood which the bees have to uncap and remove a high percentage (c90%?) of the pupa within a 12 hour period. I can't claim to have seen that in my colonies because I haven't done that test. The pin-prick test is an alternative to freeze killing, and I will be doing that pretty soon, but it does provide a signal to the bees that something is wrong with the section of brood so can't really be a conclusive proof of VSH.
I believe, from what others have told me, that it does exist separately.

 

[pargyle]

Pargyle will confirm that you plough a pretty lonely furrow if you try talking to most beekeepers about not treating bees prophylactically - 'just in case'. He has not needed to treat his colonies for a couple of years. To many, Integrated Pest Management means changing the chemical types occasionally whereas it surely must mean more than that - only treating if there is a problem would be a start!


CVB

Well, you are bang on there ... however, I'm heartened by the fact that more and more non-treaters are coming out of the closet ... many with far more years of beekeeping than I have and with, very clearly, much more knowledge of bees and beekeeping. I know of several now that have been treatment free for between 8 and 10 years but to hear that B+ is now into 20 year plus of non treatment (with bees still alive !) is very encouraging.

I don't begin to understand (yet) what it is that allows bees to survive in the face of varroa but, clearly, some do ... and let's hope that people with more knowledge than I have can start and discover what it is that enables bees or their environment to sustain the mite threat. Sadly, the money still seems to be bent on creating chemical treatments ... let's face it ... there's no money to be made from telling people to keep their bees warm and dry and let them do what they want to do and not a lot from creating bee strains that don't need treatment ... so, it may be a long wait.

 

[B+.]

let's face it ... there's no money to be made from telling people to keep their bees warm and dry and let them do what they want to do and not a lot from creating bee strains that don't need treatment ... so, it may be a long wait.

As my id says: B+., or, "Be Positive"!

All you ever wanted to know about varroa (and probably more than you wanted to know) http://www.coloss.org/beebook/II/varroa

 

[charlievictorbravo]

... let's face it ... there's no money to be made from telling people to keep their bees warm and dry and let them do what they want to do and not a lot from creating bee strains that don't need treatment ... so, it may be a long wait.

You're becoming cynical in your old age, Phil. The link below is to a PhD paper from one of Prof Ratnieks' post graduates and was part sponsored by the BBKA.
http://sro.sussex.ac.uk/51384/1/Bigio,_Gianluigi.pdf

It's a pity that some commercial organisation has not taken up the raising and distribution of hygienic bees. The student who wrote the paper has returned to Italy and works for a honey producers organisation - if I were to be cynical, I'd say we'll be buying hygienic bees from Italy within a few years, just like Malling rootstocks all over again!

CVB

 

[BeeJayBee]

... however, I'm heartened by the fact that more and more non-treaters are coming out of the closet ... many with far more years of beekeeping than I have and with, very clearly, much more knowledge of bees and beekeeping. I know of several now that have been treatment free for between 8 and 10 years but to hear that B+ is now into 20 year plus of non treatment (with bees still alive !) is very encouraging.

We've got several 'non-treaters' in our association, they aren't ridiculed. We've also had Ron Hoskins to give a talk, it was brilliant and quite encouraging too.

I don't begin to understand (yet) what it is that allows bees to survive in the face of varroa but, clearly, some do ... and let's hope that people with more knowledge than I have can start and discover what it is that enables bees or their environment to sustain the mite threat.

If a colony dies, the chances are that that particular mini-strain of mite also dies out so, to some extent, we need to rely on parallel evolution. It's a poor parasite that kills its' host, so both need to survive for either to succeed.

As far as I know, our bees used to cope well enough with Braula, but it might be a different matter if Braula had moved to Asia. As it is, we got the mite which A. cerana seems to be able to deal with varroa, I think by careful grooming (?? .. could easily be wrong).

What we do need to be able to deal with, though, is the increased virility of the DWV virus vectored by varroa.

 

[Hivemaker.]

I haven't treated my bees since the early 1990's. Around 1993 or 1994 if memory serves me right.

Where were keeping bees that had varroa at this time?

 

[B+.]

Where were keeping bees that had varroa at this time?

Same places I do now. If you're asking what is different, I would have to say that I am using more island mated Carniolans now

 

[pargyle]

You're becoming cynical in your old age, Phil. The link below is to a PhD paper from one of Prof Ratnieks' post graduates and was part sponsored by the BBKA.
http://sro.sussex.ac.uk/51384/1/Bigio,_Gianluigi.pdf

It's a pity that some commercial organisation has not taken up the raising and distribution of hygienic bees. The student who wrote the paper has returned to Italy and works for a honey producers organisation - if I were to be cynical, I'd say we'll be buying hygienic bees from Italy within a few years, just like Malling rootstocks all over again!

CVB

Yes I am ... but it's an interesting if slighly limited thesis .. I've scan read most of it and I can see that there is evidence that hygienic behaviour can be bred into bees by selective breeding of queens of colonies that show this trait. There is hope that these 'hygienic' colonies would also find the ability to deal with varroa infestation . and this may, indeed, be the case.

I noted that it was, in part, funded by the BBKA and I'm glad to see that some of my annual subscription went to a worthy cause ... just a pity that the recipient has now pushed off back to Italy !!

Perhaps a follow up study using these same bees but measuring the effect on mites in the colony would be a useful PhD for someone up there in LASI ? I didn't see anywhere in the thesis (I may have missed it ?) where reference was made to treatment for varroa in the colonies used for the experiment. A further study allowing such colonies to evolve in a treatment free environment may also yield some interesting results ... who knows, they may already be underway ?

However, BeeJayBee is right .. it's the vectored diseases that are the main threat from varroa - not the actual mite itself.

 

[charlievictorbravo]

What's this

I started this thread because I had a spike in mite drop and was seeking identification of items found on the board. Another Varroa, the only one today, was on the board and is shown in the photo.

It appeared to be a barely mature mite with no legs and covered in what appear to be eggs. The lack of legs could be explained by bees having a chew of the mite, though there were no dents on the carapace - it also seems very skinny. The real mystery for me is the "eggs" - anybody any thoughts on what they might be - they seem very uniform in size.

CVB

 

[pargyle]

Looks like mites on mite !! I've no idea ...

 

[charlievictorbravo]

Looks like mites on mite !! I've no idea ...

What, a bit like:

Big mites have little mites,
Upon their backs to bite 'em,
And little mites have lesser mites,
and so, ad infinitum.

(with apologies to Jonathan Swift)

CVB