Worldwide Beekeeping
Beekeeping => Pests and Diseases => Topic started by: Jen on June 29, 2016, 02:33:52 pm
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I was in one of my nucs a couple days ago and notice one, just one, bee with deformed wing virus, wings curled up and stick like. There are no other bees on the grass crawling around with no wings. Now that this bee is infected with DWV, can she herself infect the colony?
(https://s31.postimg.cc/8uwfjk3iv/DSCF0886.jpg) (https://postimg.cc/image/8uwfjk3iv/)
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Wish I could help but as of right now not much help. But I am very interested to see what everyone has to say about this, nice photo to :t3816:
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As with mice, where you see one, there is a hundred you don't see. Better do a mite check.
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Hey iddee, is DWV caused by mites or is it a virus transmitted from the mite to the bee?
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Transmitted by the mite.
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green bee, dwv is carried by and transmitted by the v mite. if we start seeing this and as jen's pic show, need to do a mite count as iddee suggested.
upon seeing this myself, i would start opening cells.
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Now does her photo suggest a major infestation of mites or could you see this when the mites have a lower population in the hive.
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Jen raises a good question to. Once infected can the bee transmit DWV to another bee. Sorry for all the questions. Just seems like a good time to learn something.
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The higher the mite population the more cells that will be exposed thus the higher number of possible infected bees.
It is transfered to the pupa while the mites are feeding on it. To the best of my knowledge.
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Man I got a lot to learn :eusa_wall:
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apis is correct green bee, mite infestation begins at the larval stage, but as apis said it is in the pupal stage when the mites begin to feed. (i think there is some scientific evidence for viruses in the larval stage). as far as dmv, adult bees don't transfer this, but there are other viruses that nurse bees can transfer to developing bees.
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Gbee, the mites are real hard to see, they bury themselves in the folds of the bees. The second pic shows a bee with 2 mites on it and a deformed wing. If you see deformed wings on your bees, it time to do a mite treatment PRONTO!
Varroa mites suck the fluids out of the bee body and leave holes behind. It's real sad to see bees waddling around on the ground, they can't take flight and just die off.
(https://s32.postimg.cc/lp2r1nda9/image.jpg) (https://postimg.cc/image/lp2r1nda9/)
(https://s31.postimg.cc/6cbcphx87/dwv2.jpg) (https://postimg.cc/image/6cbcphx87/)
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So how do you do a mite count?
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Horizontal transmission from drone semen to queen & Vertical transmission of the virus from the queen to egg has also been documented. Read about it here. (http://www.ncbi.nlm.nih.gov/pubmed/17622639)
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Gbee, let me locate the site with Randy Oliver and his scientific studies on how to do a mite count. There are different options. I like screen bottom boards where I can put a sticky board under the screened bottom, wait about 3 days then, pull it out and see how many mites have dropped onto the board. You multiply the count of mites by 100... That will give you an idea of how many more mites are still hanging out in the hive. If I see 10 living mites on the sticky board that means there are 1,000 nasty little buggers eating my bees. Then I do a Oxalic Treatment.
Here ya go..
http://scientificbeekeeping.com/varroa-management/mite-monitoring-methods/
Also Gbee, I have gotten my best hive management information from scientificbeekeeping.com, other than this forum.
Also, don't be shy about asking A LOT of questions about this side of beekeeping, you're going to need to know this stuff :)
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"So how do you do a mite count?"
many ways as jen said, and randy oliver's website is a great source of info........
here is the powdered sugar roll developed from the university of minnesota:
Powder Sugar Roll For Varroa Mites on Honey Bees (http://articles.extension.org/mediawiki/files/e/e1/VarroaMites_155.pdf)
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Thanks Riverbee, I have done the sugar roll before and it work out just fine.
Gbee, there is also what's called an ether roll or alcohol roll. Many beeks use this method, but it does kill 1 cups worth of bees, per hive, to get your count. Just me, I don't want to kill any bees to get a mite count.
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Thanks guys for all the great info, hopefully by the time I get started I'll be a little more familiar with things such as this. I think I am going to invest in some good books with lots of pictures. But it looks like there's a lot of good folks here willing to give sound advise when needed. So thank you all!!!
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Don't forget youtube Bbee, lots of info there too.
Read up on www.scientificbeekeeping.com, Randy Oliver is great, very educated, and a nice sense of humor as well.
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Jen, what's crazy is I thought you were on top of the mite situation in your hives. Don't you routinely check and treat your hives?
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Hi Tbone, I've done a lot of splits and nuc making this year, that's what I'm learning. So that process gives the hives brood break which reduces the mite problem. I've been checking my sticky boards all season and haven't seen more than 5 mites or so. Then I see this poor bee in one of my nucs, and my alarms went up. So I was confuses because I only saw one bee like that... weird.
Anyway, it's got my attention now :) 8)
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Hey Jen,
Sticky boards have been found to be very unreliable for monitoring mite levels. Randy Oliver states this on his website and there's research supporting this. I frequent a couple of bee clubs here and am astounded at the number of members who have lost their hives. When I ask how they monitor their mite levels; 100% said white boards. The sugar roll is in excess of 92% reliable compared to an alcohol wash. The ether roll is considered to be the least reliable method for monitoring mites. Good Luck.
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Hi BCom :) Personally, I feel that the sticky boards work best for me. Randy Oliver also said that if you count 10 mites on the sticky board, multiply it by 100, and that would be approx the average of how many mites are up in the hive. I haven't lost a hive yet to mites.
When I do see 10 or more mites, I do an oxalic treatment, and I can 'almost' guarantee a 1,000 - 2,000 mite kill. I know this because in the beginning of learning about my OA treatments, I pain stakenly counted the kill after the treatments, so I can eye ball it now.
For me, I don't want to rattle a cups worth of bees in a sugar shake just for a mite count, which also leaves sugar on the ground for ants. And I refuse to kill a cups worth of bees in an alchohol roll just for a mite count. Just me ;) 8)
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...The ether roll is considered to be the least reliable method for monitoring mites. Good Luck.
Could you help me understand where this comes from? I thought I had read RO saying the opposite. :)
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...The ether roll is considered to be the least reliable method for monitoring mites. Good Luck.
Could you help me understand where this comes from? I thought I had read RO saying the opposite. :)
There's been several studies on the efficacy of monitoring methods of which ether rolls and sticky boards are at the bottom of the list. Here's a link to a publication I think is great. I use the powdered sugar roll. It is simple, easy on the bees and found to be in excess of 92% accurate. When you dump the bees back in the hive that are coated with powdered sugar, it's like desert!
http://honeybeehealthcoalition.org/wp-content/uploads/2015/08/HBHC-Guide_Varroa-Interactive-PDF.pdf
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More on Monitoring Mites: Straight from Randy Oliver's web site:
Ether roll
The ether roll is very quick, and therefore commonly used by commercial beekeepers. Shake 300 bees from the brood nest into a jar (best with a jar that has an opening large enough for your hand, so you can wipe out the mites between tests). Spray automotive starter fluid ether into the jar for 1-2 seconds. Screw on the lid and shake the jar top to bottom for a few seconds, then roll the jar for 10-30 seconds. The bees will disgorge nectar, and the mites will stick to the sides of the jar (wet the jar with a little syrup if there’s no nectar flow) where you can count them. This method recovers only 50-75% of the mites if done carefully, and can vary wildly test to test for the same colony! A single test can easily miss low infestation levels. Therefore, take a lot of samples from a beeyard. Note: if you dump the bees out quickly, some may recover!
Stickies
Stickyboards are generally the most accurate and consistent method of estimating the total mite population, since they monitor the entire colony, rather than just a sample of the bees.
Update March 2015: I have since found natural mite fall on sticky boards to be unreliable as an indicator of mite infestation levels. For more up to date information, please see Mite Monitoring, Improved Mite Washer, and especially Mite Management Update 2013.