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  1. #1
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    Default TF success and mite type: any correlation?

    P. Rosenkranz notes in this excellent article http://www.moraybeedinosaurs.co.uk/V...rol-Varroa.pdf about the biology of varroa the following:

    "The Korean type has worldwide spread on A. mellifera, while the Japanese / Thailand type has only been reported from A. mellifera colonies in Japan, Thailand and North and South America (Anderson and Trueman,
    2000; De Guzman et al., 1998; Garrido et al., 2003; Muñoz et al., 2008). " p. 597

    The first type is more virulent than the second.

    What we know? In some places some queens are successful dealing with varroa mites, but when her daughters are taken to other places do not work so well.

    If P. Rosenkranz is correct we can put this hypothesis: in some places some TF queens are successful at a colony level if the type of varroa that colonizes the hives is less virulent.

    I have no idea if this hypothesis has already been properly tested.

    Glycerin oxalic strips tested in Portugal and Spain were not as effective as the results reported in South America. One of the explanatory hypotheses is the difference in varroas' virulence in the two continents.

  2. #2
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    Default Re: TF success and mite type: any correlation?

    As far as I know we only have one varroa sub species in the US. Concerns of others jumping species in Asia could be another threat.

    http://journals.plos.org/plosone/art...l.pone.0135103

    As fast as varroa spread through the entire country/continent in the 90s it is very likely they continually get around just as fast, your mites are my mites...(or soon will be with global trade) If there were a more virulent varroa to include pesticide selected one it's likely to spread just as quick.

    As we play around with these mites and throw every pesticide, at every possiable dose. We kill 96% of the weak mites and breed the strongest 4%. At the same time propping up and breeding the weakest bees with more and more treatments needed to keep them alive. We see ever increasing winter losses. Is it the mite or the bee?

    >What we know? In some places some queens are successful dealing with varroa mites, but when her daughters are taken to other places do not work so well.

    It is likely she and her attendants also bring along mites with them. It seems that when TF bees are taken to areas that have lots of treated bees they can't be TF. When treated bees are taken to isolated areas most don't make it, they go through a genetic bottle neck and possibly a host-parasite coevolution.

    This study might suggest it's the bee's genes that are mite tolerant.
    and on a side note the pesticides we give our bees also make them weaker.

    http://www.beesource.com/forums/show...47#post1504547

  3. #3
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    Default Re: TF success and mite type: any correlation?

    As far as I can tell FlowerPlanter is right. We only have the one here, but there is some validity to your question. We are all raising mites whether we like it or not. I want to raise mites that can live with bees and not mites that kill bees.
    Michael Bush bushfarms.com/bees.htm "Everything works if you let it." ThePracticalBeekeeper.com 42y 40h 39yTF

  4. #4
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    Default Re: TF success and mite type: any correlation?

    More articles where the two types of varroa destructor and their geographic distribution are mentioned: type K and type J.

    F Planter I did not mention sub-species, I mentioned "types" the same designation that the cited author uses.

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1634981/

    https://hal.inria.fr/file/index/doci...l-00890789.pdf

    http://www.um.es/prinum/uploaded/fil...20al_JAR08.pdf

  5. #5
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    Default Re: TF success and mite type: any correlation?

    According to your study you just linked in US we have both?

    "Randomly amplified polymorphic DNA (RAPD) markers (Kraus & Hunt 1995) also displayed a very low genetic variation within populations. Subsequent RAPD surveys distinguished two types of Varroa (de Guzman et al. 1997): one, the R (for Russian) type corresponded to mites from the United States, Russia, Morocco, Germany, Italy, Spain and Portugal populations and the other, the J (for Japan) type, to populations from Japan, Brazil and Puerto Rico and an admixture of both in North America (de Guzman et al. 1999). These two types carry the Korea and Japan haplotypes, respectively, and following Anderson (2000), are hereafter referred to as Korea or K (= Russia) and Japan or J types. The K type is highly virulent on A. mellifera, but the J type is far less aggressive (Delfinado-Baker 1988)."

    If this is true then like I said before they are likely spread across the North America. And likely the more virulent would dominate. "Your mite is my mite".

    Many have treatment free bees here most in isolated area away from treated bees. And it seems to be the honey genes not the mite.

    The genetic markers they are using to track the DNA, might also show that these mites are going everywhere and continents do not limit their movement.

    With that we need to be very carful (not just as a country) how we selectively breed our mites.

    >Glycerin oxalic strips tested in Portugal and Spain were not as effective as the results reported in South America. One of the explanatory hypotheses is the difference in varroas' virulence in the two continents.

    Do you think this could be cause Portugal and Spain have been using oxalic acid a lot longer then South America? Selective breeding?;

    http://www.beesource.com/forums/show...39#post1482139


    R Oliver;


  6. #6

    Default Re: TF success and mite type: any correlation?

    Quote Originally Posted by FlowerPlanter View Post
    And likely the more virulent would dominate.
    Why so?
    Let me never fall into the vulgar mistake of dreaming that I am persecuted whenever I am contradicted. - Emerson

  7. #7
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    Default Re: TF success and mite type: any correlation?

    Quote Originally Posted by beemandan View Post
    Why so?
    Could it be any other way?

    From ED's post#4, first study;

    'We suspect that the last explanation is the correct one; it implies that the K type, far more virulent, is displacing the K type in many countries."

    Fom the study in post in #2;

    "Since apiculture has facilitated the global transmission of Varroa, selection will inevitably favor the most virulent types in A. mellifera as seen for the global spread of the Korean haplotype."

  8. #8

    Default Re: TF success and mite type: any correlation?

    Quote Originally Posted by FlowerPlanter View Post
    Could it be any other way?
    A couple of folks made the statement....doesn't explain it....at least not to me.
    If I were applying my thinking to it....I'd say it would be the opposite. The more virulent the more likely they kill their hosts. Why would that cause them to be more successful? It probably makes sense but I don't see it.
    Last edited by beemandan; 02-02-2017 at 12:23 PM.
    Let me never fall into the vulgar mistake of dreaming that I am persecuted whenever I am contradicted. - Emerson

  9. #9
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    Default Re: TF success and mite type: any correlation?

    Virulence is associated with horizontal transmission of disease. Mites spread horizontally, as opposed to vertically. The enormous literature researching why some diseases remain or increase in virulence all support the supposition that high horizontal transmission rates encourages virulence.

    By maintaining weakened and dying colonies (a la "Bond Testing"), the keepers of these are simply encouraging the propagation of virulent strains.

  10. #10
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    Default Re: TF success and mite type: any correlation?

    Doubtful to me that it is as simple as mite type. ( OR bee gut or mite gut, etc.)
    Is the tick carrying Lyme more virulent than the non carrying tick? Probably not to the tick.

    From the tick's view a sick sedentary host (below a fatal level) is probably a superior host.

    A collapsing hive is a great vector for the mite.

    I see no reason that both a virulent strain and a sub lethal strain would not be to the mite's advantage.

  11. #11
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    Default Re: TF success and mite type: any correlation?

    Quote Originally Posted by beemandan View Post
    A couple of folks made the statement....doesn't explain it....at least not to me.
    If I were applying my thinking to it....I'd say it would be the opposite. The more virulent the more likely they kill their hosts. Why would that cause them to be more successful? It probably makes sense but I don't see it.
    That's exactly what varroa destructor does (did) it killed it's host wiped out 99.99% of feral hives (so they say) and every untreated hive in America in the 90s. The only hives that survived; rare feral hives and the treated domesticated hives. If the varroa destructor was any more virulent we may have lost our feral bees (still poses a threat) and may have to treat our domestic hives more often with stronger pesticides (maybe what we see today). If varroa is too virulent that it kills the host before it could spread then it would not be a problem.

    If varroa was not a clonal spices it could breed in lower virulent traits into is their gene pool. Especially if these traits did not kill their host; there would be more of the survivor that did not kill the host verse less survivor that kill the host.

    Quote Originally Posted by JWChesnut View Post
    By maintaining weakened and dying colonies (a la "Bond Testing"), the keepers of these are simply encouraging the propagation of virulent strains.
    Not necessary; By maintaining colonies that require treatments "the keepers of these are simply encouraging the propagation of virulent strains.". By what means does one maintain healthy strong colonies; pesticide selection? What if the weakened and dying colonies have more resistance than the treated colonies?
    Last edited by FlowerPlanter; 02-02-2017 at 03:13 PM. Reason: typo

  12. #12
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    Default Re: TF success and mite type: any correlation?

    Quote Originally Posted by FlowerPlanter View Post
    Do you think this could be cause Portugal and Spain have been using oxalic acid a lot longer then South America? Selective breeding?
    FP in a portuguese survey conducted in 2016 on a sample of 8000 hives 7% were treated with oxalic acid. Oxalic acid treatment is recent in Portugal, unlike northern and central Europe. In our country, given the weather conditions, the brood stop or does not happen or happens for short periods. For this reason I believe that most of portuguese beekeepers are not using it.

    Quote Originally Posted by Saltybee View Post
    Doubtful to me that it is as simple as mite type.
    Like you I do not believe in unique causes, timeless and universal, for nothing in this world. This aspect (mite type) could be one more to join to several others.

  13. #13
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    Default Re: TF success and mite type: any correlation?

    attacking the varroa problem from the mite side of the equation does make sense eduardo. i'm not sure much research money is being spent on that but perhaps more should be.

    jwchestnut is correct in pointing out that higher virulence is selected for considering horizontal transmission along with the opportunity provided when multiple colonies are located in close proximity to each other. the 'host' is actually the whole bee yard which is usually never completely 'killed'.

    what few colonies i've had that did succumb to varroa most often died out during the winter months. i assume the mites that caused the collapse also died out. i've wondered if that dynamic in this area has over time selected for less virulent mites.
    journaling the growth of a treatment free apiary started in 2010. 20+/- hives

  14. #14

    Default Re: TF success and mite type: any correlation?

    While you develop a treatment free apiary, you should take samples of your mites continuously. So later you can go back in time and see, how your mites changed or not. I have dozens of small plastic bags with mites from the last ten years that I sampled. Thought it might be interesting to look for some day.

  15. #15
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    Default Re: TF success and mite type: any correlation?

    Probably the most powerful argument in favour of natural swarming is to do with the control of disease in the bee population. Swarming is associated with only vertical transmission of disease, which theory predicts will select for low pathogen virulence, milder pathogens, if you like.18 This means that if the pathogen kills the host that is the end of the line for both host and pathogen. On the other hand, multiplying colonies by splitting them, as is common beekeeping practice, increases horizontal disease transmission which evolves high pathogen virulence. This is because the main reservoir for disease is usually the brood combs and the brood in them. If the pathogen kills off one part of a split there is still a chance for another part to survive and propagate the pathogen. It is not the end of the line for the pathogen. And even if all parts of a split fail there is still infected comb and equipment present to spread disease, e.g. through robbing. Helped by common beekeeping practices, pathogens can freely develop their virulence. For example, their reproductive fitness can increase, as there is less incentive to curb it sufficiently to allow the infected colony to swarm
    and thus secure the pathogen's survival by vertical transmission. The result is selection for increased lethality of pathogens.
    Out of David Heafs website.
    http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf
    Listen to good advice, then.... make your own decision. fusion_power
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  16. #16

    Default Re: TF success and mite type: any correlation?

    There is no practical way to keep bees as isolated as would be needed to hinder horizontal transmission. Bees every 800 meters? Yeah, right...

  17. #17

    Default Re: TF success and mite type: any correlation?

    There is no practical way to keep bees as isolated as would be needed to hinder horizontal transmission. Bees every 800 meters? Yeah, right...

  18. #18
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    Default Re: TF success and mite type: any correlation?

    Quote Originally Posted by Eduardo Gomes View Post
    FP in a portuguese survey conducted in 2016 on a sample of 8000 hives 7% were treated with oxalic acid.
    7% for how many decades? Europe has been using oxalic acid for a long time (believe longer than anyone else). America just recently picked it up (have no idea about South America seeing how they have a high percent Africanized that are mite tolerant I suspect there's not much oxalic acid use in resent or past, they also seem to be the world leader in organic honey). Do you all import and export bees/queens freely from Europe?

    Quote Originally Posted by squarepeg View Post
    i've wondered if that dynamic in this area has over time selected for less virulent mites.
    An inbred clonal spices that is genetically identical to its parents. If there was a genetic mutation with a lower virulent would it be quickly displaced? As the above studies suggest the displacement of the less "virulent J type".

    Quote Originally Posted by SiWolKe View Post
    On the other hand, multiplying colonies by splitting them, as is common beekeeping practice, increases horizontal disease transmission which evolves high pathogen virulence.
    This has more to do with brood diseases, mostly bacterial and contaminated comb play a big part, but can also be carried with new swarms. The viruses that mites carry do not seem to contaminate the comb and have more to do with high mite counts and the bee's resistance and tolerance to both mites and the viruses.

    Quote Originally Posted by BernhardHeuvel View Post
    There is no practical way to keep bees as isolated as would be needed to hinder horizontal transmission. Bees every 800 meters? Yeah, right...
    I believe you're correct, they would need to be separated by continents and this still proves a challenge. "your mite is my mite". And as these studies suggests the more virulent; type, crossbreed or selected mite will dominated.

  19. #19
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    Default Re: TF success and mite type: any correlation?

    flowerplanter, is it known how long the viruses persist in the hive once the bees and mites die out?
    journaling the growth of a treatment free apiary started in 2010. 20+/- hives

  20. #20
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    Default Re: TF success and mite type: any correlation?

    Quote Originally Posted by SiWolKe View Post

    Probably the most powerful argument in favour of natural swarming is to do with the control of disease in the bee population. Swarming is associated with only vertical transmission of disease, which theory predicts will select for low pathogen virulence, milder pathogens, if you like.18 This means that if the pathogen kills the host that is the end of the line for both host and pathogen. On the other hand, multiplying colonies by splitting them, as is common beekeeping practice, increases horizontal disease transmission which evolves high pathogen virulence. This is because the main reservoir for disease is usually the brood combs and the brood in them. If the pathogen kills off one part of a split there is still a chance for another part to survive and propagate the pathogen. It is not the end of the line for the pathogen. And even if all parts of a split fail there is still infected comb and equipment present to spread disease, e.g. through robbing. Helped by common beekeeping practices, pathogens can freely develop their virulence. For example, their reproductive fitness can increase, as there is less incentive to curb it sufficiently to allow the infected colony to swarm
    and thus secure the pathogen's survival by vertical transmission. The result is selection for increased lethality of pathogens.
    Out of David Heafs website.
    http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf
    The terms 'pathogen' and 'virulence' are typically applied to microbial disease-producing organisms. I do not believe it is either correct or appropriate to apply them to mites, and doing so introduces confusion and misunderstanding of the nature and characteristics of the mites and how to deal with them. Mites are an opportunistic parasite that -host- certain pathogens which are capable of infecting bees, but they are not a pathogen themselves and that quote is not applicable to them.

    I do note that some [other] articles use the term 'pathogen' in regard to varroa so I am not faulting anyone specifically for the usage, I am merely suggesting that such usage is incorrect and tends to distract/misdirect from a true understanding of the nature of varroa mites. The nature of your enemy must be understood correctly if you are to develop effective strategies to fight him.

    As an aside, I just ran across this in regard to the Chinese black honey bee, and it seems interesting:

    https://www.ars.usda.gov/research/pu...eqNo115=314017
    If you want to be successful, study successful people and do what they do.
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