Varroa Destructor Paper

Discussion in 'Pests and Diseases' started by camero7, Feb 19, 2012.

  1. camero7

    camero7 Member

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  2. Marbees

    Marbees Member

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    Great read, findings from different authors from 1987-2009. I knew that varroa vectors many viruses but 18!! Wow...
    Makes me feel good about my thymol spring and oxalic fall treatments.
    This document should be available at bee clubs as a handout for new beekeepers.
    Thanks camero7 :thumbsup:
     

  3. tecumseh

    tecumseh New Member

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    thanks for the link...

    great read and some good information there...

    a very small snip..
    A strong effect has been demonstrated for the size, height and age of the brood cell itself. Shortened brood cells, i.e. brood cells with a shorter distance be- tween the larva and the cell rim, are more frequently infested than artificially elongated brood cells. This effect was confirmed by the use of different methods with manipulated brood cells inside the honey bee colony (Boot et al., 1995a; De Ruijter and Calis, 1988; Goetz and Koeniger, 1993; Kuenen and Calderone, 2000). Also the size of the cell and the relative larval size to cell size affect the inva- sion behavior of the mites. Brood cells of European honey bees are, in general more highly infested than slightly smaller brood cells of Africanized bees within the same colony (Message and Gonçalves, 1995; Piccirillo and De Jong, 2003). However, drone brood cells con- taining smaller worker larvae are less infected than normal worker brood cells, probably an effect of too much space between the larva and cell wall (Calderone and Kuenen, 2001). Older brood cells con- taining cocoons from several brood cycles are also more highly in- fested than newly built comb (Piccirillo and De Jong, 2004). In this case, the somewhat smaller size of the old cells is presumably com- pensated by the stronger smell of the cocoons.
     
  4. tecumseh

    tecumseh New Member

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    I though I would bring this rather lengthy article to the front of the Pest and Disease forum for review....

    there are several real jewels stuck in that haystack somewhere...
     
  5. riverbee

    riverbee Active Member

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  6. tecumseh

    tecumseh New Member

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    even a casual read might suggest to folks why a program to cycle out old and bring in new wax may be one of the best varroa treatments you can employ.

    the article might also suggest why comparisons made in differing time periods may also be fairly worthless.
     
  7. camero7

    camero7 Member

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    The nugget that really hit me was the preponderance of mites in drone brood in the summer. It convinced me to use a foundationless frame in each brood box and harvest the drone brood as often as I can during the summer. My mite counts this fall were lower than last year. I still treat, since I'm convinced that mites are the killer of most hives that fail. i also lowered my threshold on mites in August to <5 - so far I still need to treat.
     
  8. Crofter

    Crofter New Member

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    If being in a shortened cell increases pupae infestion rate I wonder if it could also make detection easier for varroa sensitive bees. In one scenario smaller cell could have one implication and with a different bee population or hive condition a different finding could result.

    Raising brood in fresh cells with less liklihood of accumulated toxins seems a plus. Even small insults to a developing creature could be causing drift over many generations. That kind of subtle but ongoing influence would be difficult to test for unless you went very deliberately in search of it.

    Good article!
     
  9. pistolpete

    pistolpete New Member

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    Even with 7 years of university under my belt, I found that a bit of a heavy slog. Quite a bit of good info wrapped up in there though. I think I will be giving the mite trap frames of drone cell foundation a try this year.
     
  10. Daniel Y

    Daniel Y New Member

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    If it is accurate that mites woudl take out the colonies by the end of December. I must have done a pretty good job on getting the mites out of my colonies. 4 of 4 are still up and running as of this post. Now the question is. Do I have healthy queens?

    I was not able to open the PDF. Adobe is messed up on my computer fro some reason.
     
  11. Americasbeekeeper

    Americasbeekeeper New Member

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    It is a little disconcerting that DeJong did not recognize or consider the shorter gestation time, egg to adult, of AHB. Mildly reminiscent of another teaching beekeeper that introduced hygeinic genetics, splits hives frequently, improved the environment within his hives and concluded small cell or natural cell improves survival.
    Perhaps it is indicative of the fact Dejong has not completed any substantive research papers of late. So many other Entomologists have also disproved the original hypothesis in the last 6 years as well.
    Short cell surely goes against narrow frames as currently used in TBH and recently marketed by Dadant.
    There is an Adobe Reader 11 (XI) try upgrading.
     
  12. pistolpete

    pistolpete New Member

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    gestation time was mentioned. He argued that while shorter AHB gestation somewhat limits the reproductive success of Varroa, the extra generation of bees that are raised in a season allows the varroa to catch up interms of total population.
     
  13. ablanton

    ablanton New Member

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    It may not be your Adobe. I had the same problem. Try refreshing the page several times. After about 5 tries, I finally got it to load.
     
  14. ApisBees

    ApisBees New Member

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    Am I missing something here over the course of the year we are talking bee cycles at 20 days + time for the workers to polish the cells and the queen to relay in the cell over the course of the hole year there is only time for 1/2 a generation of bees.
     
  15. Crofter

    Crofter New Member

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    I did not go back to the article but I thought as I read it referred to an extra generation of mites. less successful in shorter capped time of bee but the extra mite cycles made it a wash.
     
  16. pistolpete

    pistolpete New Member

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    Yes, since they are only in the cell from hours before capping till emergence. I thing his point was that gestation period is not the factor that makes tropical bees more resistant to mites, but rather that a given colony will have more individual bees over the course of the year. I thought the whole point that mite tolerant bees might not be economically desirable bees is quite interesting. What do you folks out there think about the drone brood frames. It seems like a good idea to me: a frame of drone sized foundation placed in the brood nest that is removed when the drones are capped. Theoretically it seems like if this is done early enough in the season it re-sets the mite population to very low levels. The argument against it is that it takes the colony a lot of resources to produce full frames of drones. Has anyone out there tried it?
     
  17. ApisBees

    ApisBees New Member

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    Pete
    Remember Management Timing. If you miss getting the frame out of the hive before the drones emerge you have just provided the mites an ideal host environment so the mites can maximize mite populations.
     
  18. Lburou

    Lburou Member

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    Have you considered a Steele and Brodie or Dear frame? Or an Oliver frame? I'm considering one of those this season. :)