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Thread: Bees with resistance to varroa mites

  1. #11
    Senior Member fatshark's Avatar
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    I'm with mbc on this one. VSH and hygienic bees are not the same. I seem to remember Jeff Harris (Baton Rouge, VSH) saying that VSH bees do not uncap nitrogen frozen pupae and/or vice versa (or at least are no better than normal bees). His view is that VSH bees detect something volatile given off by Varroa damaged pupae.

    One thing that worries me about Varroa resistance is the selection of less pathogenic mites, rather than 'better' bees. Has Ron Hoskins ever exposed his bees to a Varroa-infested hive from outside his area?

    What about coordinated Varroa treatment? If everyone in an area treated all colonies simultaneously - for a full month with Apiguard or similar in the autumn and with OA in winter - it should leave the mites with nowhere to hide. It would have to be simultaneous and every colony because phoretic mites on drones or drifting workers mean that Varroa-free colonies are infested within days or at best weeks.

    Not Varroa resistance I know, but I'm not sure that such a thing exists.

  2. #12
    Administrator gavin's Avatar
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    Quote Originally Posted by fatshark View Post
    Not Varroa resistance I know, but I'm not sure that such a thing exists.
    Ha! We may have an argument there. Or perhaps if you mean that there is only Varroa tolerance maybe we'll agree after all. Yes, VSH is a kind of super-hygiene whereas the pin-killing or freeze-killing test just determines plain hygienic (which is useful for AFB and a little bit useful for Varroa).

    I've spent time with a beekeeper in Stirlingshire who went cold turkey (threw his babies off bridges if you like) and they bounced. He was getting long-term survival despite no treatment for 3-5 years. The bees did interesting things - VSH-type behaviour, grooming and biting (witnessed in an observation hive) and maybe other things too. We had Dennis Anderson visit one summers day and had a picnic at John's apiary. I had some of his stocks and was working up to test them by inserting frames of infested brood raised in another colony but the 2009 foulbrood epidemic caused me to treat to reduce the stress on the bees. I'll get back to it sometime.

  3. #13
    Senior Member prakel's Avatar
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    Quote Originally Posted by Jon View Post
    Some of us in the Native bee group have been discussing possible longer term projects. One of the ideas on the table is to try and identify colonies which deal with mites better than others - and selectively breed from these.
    I think this is the important phrase. Varoa tolerant/survivor strains don't necessarily express notable VSH qualities; at least, that seems to be the current thinking if we trawl what's been written.

    There's a whole package of possibilities (without ever going down the cold turkey route) to investigate so I think this thread has a few miles left in it and I'd certainly be interested to see where the Irish Bee Society takes their study if it gets off the ground.

    One point about the pin prick test, there's been a lot of cautionary comments (but I can't find any of them in a quick search now!) as to it's value due to the physical perforation of the capping unlike the freezer and liquid nitrogen methods.

  4. #14
    Senior Member Jon's Avatar
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    Quote Originally Posted by The Drone Ranger View Post
    Hi Jon
    About the middle of this article is a pin prick test

    Jerry Bromenshenk reckons the pin prick method is not reliable.

    I invented the liquid nitrogen freeze method while working on a project for
    EPA. I found that neither the pin prick nor Steve Tabor's - cut and
    freeze in freezer- produced consistent results. The problem is that physical
    damage (pricking, cutting out bits of comb) can induce a repair behavior.
    Hygenic behavior is supposedly controlled by two genes, each with a bit
    different behavior. Also, removal of paper is probably not a good test -
    its just part of a two step process.

    As per area of brood - the larger the area you kill, the more certain you
    will be to see bees take action - that's again not simply hygienic
    behavior, but a response to a damage 'crisis'.

    What most have forgotten - our data showed that several small patches over
    more than on brood frame provided the most reliable test.

  5. #15
    Senior Member prakel's Avatar
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    re: post #14.

    That's a more accurate explanation!
    Last edited by prakel; 15-05-2013 at 07:27 AM.

  6. #16
    Senior Member Jon's Avatar
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    In prakel's IWF video about 6.30 it mentions that bees with parasites often leave the hive this minimising the varroa load.
    I wonder if this is a significant behaviour and has anyone measured it?
    It has been known for a long time that sick bees do the decent thing aka a 'Captain Oates.' (possibly more accurately describes as altruistic suicide!)
    Last edited by Jon; 15-05-2013 at 09:31 AM. Reason: clarity

  7. #17
    Administrator gavin's Avatar
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    LOL! We've had the Bond Experiment and now we can have Captain Oates Behaviour. The aforementioned John was sure that his bees were Doing The Right Thing a la Captain Oates - from both watching (in an observation hive) groomers gathering up mites, and seeing that a spring surge of deaths in the snow were all carrying mites.

    Altruistic suicide (and possibly simply cleaning up by carrying pests outside where no doubt they may select a hot wall or a branch over a cold pond where they can pick them off and jetison their load).

    This kind of thing may explain the anomalous floor count data we sometimes see. The mites may never get a chance to drop there.

  8. #18

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    If you mosey around the glenn apiaries site you will find lots of links to explore
    In principle there are two separate strains of thought
    No1- is very hygienic bees rip out varroa infested larva
    No2-is varroa mites ability to breed in certain colonies is suppressed
    Ron Hoskins is route 1

    Personally I doubt it can be done
    You find insects develop resistance to static threats (ie insecticides)
    Varroa are more capable of adaptation than bees are (moving target)
    Faster reproduction rate inbreeding you name it lots of mother varroa etc

    Past experiments in breeding resistance to foulbrood etc had initial success then stalled
    Subsequent breeding from survivor colonies didn't make any further progress

    You will have noticed Ron Hoskins is using AI presumably then he can't fix the necessary traits in open mating
    There have been claims of Varroa resistant bees since the 90's but only AI line bred

    I wish anybody well that want's to tackle the task maybe the £200,000 from Scottish Gov might be best spent on this

    Let's not elevate the nut cases who go "cold Turkey" to hero status I don't want them anywhere near me they are a menace
    Last edited by The Drone Ranger; 14-05-2013 at 10:44 PM.

  9. #19
    Administrator gavin's Avatar
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    Apis cerana managed it, why not Apis mellifera?

    No 1, without biting and grooming, can leave the mite exhausted and probably running out of sperm, but it is a slow process.
    No 2 was a figment of the researchers' imaginations (until they realised). Keep turfing out the breeding mites and you are left with only the old spinsters in sealed cells. Open them up and you see non-breeding mites - just a trick (see no 1).

    Ron Hoskins, Alois Wallner, John Dews, John McLean, they were/are all focused on biting and grooming.

    For the non-believers amongst us, try this. (Sorry Jon, I seem to be regurgitating our recent correspondence).



    Somewhere near the middle there's a bee doing it all on its ownsome. It ends up on three legs while the other three are grappling with a Braula in this case, trying to get it near its mouthparts so that it can give it a sharp nip. Remarkable footage. Elsewhere in the video there are bees trying to do the same to Varroa.
    Last edited by gavin; 15-05-2013 at 09:12 AM.

  10. #20
    Senior Member prakel's Avatar
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    Quote Originally Posted by The Drone Ranger View Post
    You will have noticed Ron Hoskins is using AI presumably then he can't fix the necessary traits in open mating.

    There have been claims of Varroa resistant bees since the 90's but only AI line bred
    Regards Ron Hoskins, I believe that he's working with a statistically very small population (I may be wrong on this) which perhaps necessitates AI.

    In the US there are plenty of reports of lower VSH expression being maintained in populations by open mating. The AI simply seems to be the most efficient tool to maintain lines with high VSH expression which can then be outcrossed in the field. Sure the research has been ongoing for some time but there now (recent years) seems to be a greater drive/interest from practical beekeepers so I think that in this sense it's still very 'new'.

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