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understood and thank you.

so you keep separate tallies of single foundress mites and mite families per 100 or so purple eyed pupae?

do the scientists you are collaborating with feel like this is a better metric than the alcohol wash of adult bees?
 

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The separate tallies are to make a determination of VSH as indicated by the level of reproducing mites. From a paper by Harbo, Harris etc. "Selecting for Varroa Sensitive Hygiene
Bee Health November 12, 2010"
Select for low levels of reproductive mites.
Random population of mites 15-25% are non reproductive.
Breeder Queens should be selected from hives with 75 +% non reproductive.
 

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My strategy is to dominate my mating areas with lots of bees and drones. On one hand more isolation would be useful, but on the other, I think a touch of mixing with other stock could bring some benefits. I could gain some useful characteristics from it. This is the first year I have implemented this strategy. However, I would not say that the bees in my proximate mating yards were ideal. Better than completely unselected bees, but could be much better. I have more information with my brood sampling for this year, and will have a broader base for selection after this coming season.
lharder:

While I haven't the experience you have to draw from, your plan seems sound to me. I am excited and hopeful that Randy Oliver is correct when he asserts:

"Even purebred breeds hide aspects of their genetic heritage from us [6]. Two factors may cause these hidden traits to come to the fore: environmental factors or crossbreeding.

Darwin noted that the first generation of escaped domestic animals might exhibit minor phenotypical changes, in response to environmental cues, such growing more hair when it got cold. But what really caught his (and should catch our) attention was what could happen when two purebred breeds were “crossed.” The resulting hybrid [7] offspring are often noticeably different from either parent:

With crossed breeds, the act of crossing in itself certainly leads to the recovery of long-lost characters, as well as those derived from either parent form…From what we see of the power and scope of reversion, both in pure races, and when varieties…are crossed, we may infer that characters of almost every kind are capable of reappearing after having been lost for a great length of time.

He further noted that the most common form of reversion, “almost universal with the offspring from a cross, [is to go back] to the characters proper to either pure parent form.”

I share Darwin’s fascination with this clearly observable phenomenon.

Practical application: when queens of a managed stock mate with drones of other stocks, the resulting offspring may exhibit wild-type traits that had long lain dormant. Could this be the basis of a wild-type feral population, originally founded by escaped swarms from a variety of domesticated lines?"


http://scientificbeekeeping.com/wha...omesticated-and-feral-bees/#reversion-to-wild

The separate tallies are to make a determination of VSH as indicated by the level of reproducing mites. From a paper by Harbo, Harris etc. "Selecting for Varroa Sensitive Hygiene
Bee Health November 12, 2010"
Select for low levels of reproductive mites.
Random population of mites 15-25% are non reproductive.
Breeder Queens should be selected from hives with 75 +% non reproductive.
John:

Thank you for outlining the VSH testing protocol- if I understand Mr. Harbo's breeding protocols, it appears he prefers to AI queens from single drones for maximum effect?

"I described a method for getting the most information about VSH with minimal effort. Mistakes will be made. However, unlike maintaining pure pedigrees, it is usually simple to re-establish a measurable trait such as VSH. Most errors come from evaluating and breeding from queens that are multiply mated or free-mated. This is because the VSH trait is expressed at a high level when only some of the bees in a colony express the trait. Therefore, some colonies with freemated VSH queens score as high as the best VSH breeder queens. But, when grafting from such a colony, some of the daughter queens will have a much lower level of the VSH trait than expected. For maximum precision, evaluate progeny of queens that have been inseminated with semen from a single drone."

http://static1.1.sqspcdn.com/static...018pdf.pdf?token=HrjMxTk8fADTTxn6gH9amOohXDM=

I also noted that Mr. Harbo "...will not be offering breeder queens for sale in 2019 but will be focusing our resources on evaluating new selection methods and expanding the diversity of our varroa resistant bees."

I wonder if he is evaluating whether to explore a more open-mated approach while dominating his local DCA's similar to what lharder is attempting to do?
 

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The separate tallies are to make a determination of VSH as indicated by the level of reproducing mites. From a paper by Harbo, Harris etc. "Selecting for Varroa Sensitive Hygiene
Bee Health November 12, 2010"
Select for low levels of reproductive mites.
Random population of mites 15-25% are non reproductive.
Breeder Queens should be selected from hives with 75 +% non reproductive.
thank you for that john.

so is the measure of % mite families used for selection vs. % infested cells or % infestation on adult bees via alcohol wash?

(i'll try to find and read the harbo paper, thanks again)
 

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thank you for that john.

so is the measure of % mite families used for selection vs. % infested cells or % infestation on adult bees via alcohol wash?

(i'll try to find and read the harbo paper, thanks again)
In Europe the selection criteria is: mites (under cell cover) found with no offspring / total number of mites found (under cell cover)

When this equation is low then the number off mites on adult bees is not important (it remains naturally low).
When infestation is low the tested hives are usually artificially infested (with mites from other hives), in this way the amount of needed work(opening and inspecting cells with microscope) is reduced.
 

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In Europe the selection criteria is: mites (under cell cover) found with no offspring / total number of mites found (under cell cover)

When this equation is low then the number off mites on adult bees is not important (it remains naturally low).
When infestation is low the tested hives are usually artificially infested (with mites from other hives), in this way the amount of needed work(opening and inspecting cells with microscope) is reduced.
thank you for that excellent explanation juhani.

when the infestation is low, and if one doesn't add a frame from an infested hive, is it necessary to keep opening cells until some minimum number is reached for the equation to have meaning?
 

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thank you for that excellent explanation juhani.

when the infestation is low, and if one doesn't add a frame from an infested hive, is it necessary to keep opening cells until some minimum number is reached for the equation to have meaning?
Infestation is done by taking bees of infested hives and "washing " mites off the bees with powder sugar. (Powder sugar has to be watered away quickly to keep the mites alive.) This way just mites are added to the hives in test.

The artificial infestation is done just for what you wrote.
It is not practical to open 500 cells and find just 5 mites. Nor is the result reliable.
 

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Discussion Starter #369
lharder:

While I haven't the experience you have to draw from, your plan seems sound to me. I am excited and hopeful that Randy Oliver is correct when he asserts:

"Even purebred breeds hide aspects of their genetic heritage from us [6]. Two factors may cause these hidden traits to come to the fore: environmental factors or crossbreeding.

Darwin noted that the first generation of escaped domestic animals might exhibit minor phenotypical changes, in response to environmental cues, such growing more hair when it got cold. But what really caught his (and should catch our) attention was what could happen when two purebred breeds were “crossed.” The resulting hybrid [7] offspring are often noticeably different from either parent:

With crossed breeds, the act of crossing in itself certainly leads to the recovery of long-lost characters, as well as those derived from either parent form…From what we see of the power and scope of reversion, both in pure races, and when varieties…are crossed, we may infer that characters of almost every kind are capable of reappearing after having been lost for a great length of time.

He further noted that the most common form of reversion, “almost universal with the offspring from a cross, [is to go back] to the characters proper to either pure parent form.”

I share Darwin’s fascination with this clearly observable phenomenon.

Practical application: when queens of a managed stock mate with drones of other stocks, the resulting offspring may exhibit wild-type traits that had long lain dormant. Could this be the basis of a wild-type feral population, originally founded by escaped swarms from a variety of domesticated lines?"


http://scientificbeekeeping.com/wha...omesticated-and-feral-bees/#reversion-to-wild



John:

Thank you for outlining the VSH testing protocol- if I understand Mr. Harbo's breeding protocols, it appears he prefers to AI queens from single drones for maximum effect?

"I described a method for getting the most information about VSH with minimal effort. Mistakes will be made. However, unlike maintaining pure pedigrees, it is usually simple to re-establish a measurable trait such as VSH. Most errors come from evaluating and breeding from queens that are multiply mated or free-mated. This is because the VSH trait is expressed at a high level when only some of the bees in a colony express the trait. Therefore, some colonies with freemated VSH queens score as high as the best VSH breeder queens. But, when grafting from such a colony, some of the daughter queens will have a much lower level of the VSH trait than expected. For maximum precision, evaluate progeny of queens that have been inseminated with semen from a single drone."

http://static1.1.sqspcdn.com/static...018pdf.pdf?token=HrjMxTk8fADTTxn6gH9amOohXDM=

I also noted that Mr. Harbo "...will not be offering breeder queens for sale in 2019 but will be focusing our resources on evaluating new selection methods and expanding the diversity of our varroa resistant bees."

I wonder if he is evaluating whether to explore a more open-mated approach while dominating his local DCA's similar to what lharder is attempting to do?
Yes I think its some sort of principle in biology that things respond to stimuli. Take away the stimuli and no response is seen. It happens at different scales of organization. For example, when I was an arborist, a damaged tree could be held together with a cabling system. However, once outside support is provided, the tree no longer lays down wood in response to wind and it becomes completely dependant on the support system which must be maintained. I generally refused to put them in as most people have short attention span and the tree becomes a liability. A tree grows its support system in response to its environment. Expose them to new forces (removing trees around them) and their roots cannot take new wind forces at play and yo get lots of windfall. Make changes slowly and the trees will respond over time to change.

The argument that bees are livestock like some ill bred pure bred dog is kind of silly to me. Many of our bees deal with natural often hostile environments and need to deal with it. At any rate, if you look at a population of bees as a system and we are interested in mechanisms of regulation, then the comparison between feral and domesticated is irrelevant. Both are subject to environmental forces and we need to make sensible decisions about whether we incorporate system regulation or ignore it. But there are consequences either way.
 

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Discussion Starter #370 (Edited)
In terms of hierarchy, my selection is survival, then low mite count, then something like VSH or mite biting. When mite counts get very low, then it seems silly to overthink it, add mites to the system then select against that colony if VSH isn't the mechanism. We need to think multivariable solutions to multivariable problems. I'm not interested is VSH per se, just one means to an end. But I am very interested to see if it is maintained in my population under my selection criteria.

But I am interested in low mite counts. In theory, I should be more interested in survival and production. We don't actually know what an optimum number of mites in relation to production actually is. It could be 10 percent where squarepeg operates in the absence of viral chaos. But it could be 5 percent in others. But to be able to select for low counts is an important fact that needs to be shown to the beekeeping industry in general. If landscape selection (every beekeeper selects tf or not) then some progress can be made in bee health. For this reason it is important to connect at a level that average beekeepers can understand. Talking about selection for low mites is a good starting point.
 

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Discussion Starter #371
understood and thank you.

so you keep separate tallies of single foundress mites and mite families per 100 or so purple eyed pupae?

do the scientists you are collaborating with feel like this is a better metric than the alcohol wash of adult bees?
No I used my own poor judgement to make this decision. I watched lots of mite samples being taken and after thinking about it, it didn't seem to offer information with enough resolution. The effort vs information didn't seem quite there. Too many other things could be happening. The importance of winter bees for winter survival seemed paramount to me. Brood samples would show infestation at this critical time in later summer early fall in colonies that have had mites for at least 2 summers and one winter. It also allows me to track VSH in my population. Over time it should show it maintaining or waxing or waning in my system. It also shows me the variation within my population and perhaps guide me to more consistent results as I improve my mating area. I am very much interested in variation. A certain amount is necessary for populations to track changing environments, but is the variation we see consistent with what we would see in wild populations under selection? I'm guessing not.
 

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Yes I think its some sort of principle in biology that things respond to stimuli. Take away the stimuli and no response is seen.

At any rate, if you look at a population of bees as a system and we are interested in mechanisms of regulation, then the comparison between feral and domesticated is irrelevant. Both are subject to environmental forces and we need to make sensible decisions about whether we incorporate system regulation or ignore it. But there are consequences either way.
Talking about selection for low mites is a good starting point.
lharder:

From my very humble vantage point, your approach and logic make good sense to me. Your analogy to your arborist work was helpful to me and is one that I think most people (present company included) can understand intuitively. The whole interaction between genotype (presumably the hard-wired genetic background) and the phenotype (the response to stimuli) fascinates me and gives me cause to wonder if more varroa resistance mechanisms will ultimately be unlocked as the AM species as a whole continues to adapt in the face of the pressure.

Your point about our management decisions is also astute from what little I know. The more I read and study, the less convinced I am that I personally understand enough about the multi-faceted factors which ultimately drive successful (and continued) adaptation to confidently make decisions about how to breed for resistance (though I am glad there are much smarter people than I who are developing systematic approaches to this).

That said, I think like you that mite levels seem to be the best and most critical place to start, and commensurate to this, to understand the mechanisms (both from a genetic and observational standpoint) that drive these low background levels.

I am not at all convinced that I am adding anything new to this discussion, but it is satisfying personally to rationalize through the concepts as one considers how a sustainable, inherent solution to varroa mites might be in reach for beekeepers everywhere.
 

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Discussion Starter #373
A small break in the weather yesterday. An arctic air mass is still in play, but temperatures have moderated to a mere 0 to -10 C. Still well below seasonal. It was sunny with no wind, so I took advantage of the relatively good weather to check a site of production hives for food and survival. Of the 14 I checked 10 were alive. The first 1 I checked was dead, then the next 10 were alive with the last 3 dead outs. Food stores are not a problem. I didn't have a note book with me, but I think that once I get a final tally this spring and I compare them with mite counts I took in fall, there will be some surprises. For instance, one hive had such a spotty brood pattern that I was unable to get a brood sample. It had a nice cluster. Go figure. I wonder if they were doing a massive house cleaning when I was taking samples. Also I suspect that I have lost a low mite count hive. To be confirmed.

I will be looking at hives that have these anomalies and survive with decent strength this spring. I will take a couple of brood samples and do some comparisons with hives that had lower mite counts this fall. The more this stuff is looked at it seems the less we know. I am wondering about non linear responses of bees to mite levels and how colonies make decisions about when to act.
 

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Discussion Starter #375
So it looks like spring has finally sprung. With the winter breaking I managed to look at all my sites over a couple of days.

Bad news first. My one site that was under tremendous robbing pressure last fall, had poor winter survival. Of the hives that survived into winter, only 2 out of 6 production hives, and 5 out of 8 nucs survived. I lost maybe 7 production hives before winter, so pretty bad.

Then at one of my nuc sites. I had 17 out of 29 survive. The poor survival was partly my fault. Inadequate stores coupled with lack of decent weather to check them in February/early March. Lost some nice clusters...

However at my other nuc site, I had 44 or 48 survive. Many light on stores that I will top up tomorrow. I couldn't scrounge enough from heavy hives to top everyone up. I had lots of very good or competent clusters. Pretty pleased overall.

That late cold snap really drained the overall food stores in my hives. Probably coincided when brood was being started. I probably should have cracked them open even during the harsh weather to check stores at this crucial period. It was cold and miserable though.

At my mating sites, I had 10 of 14 production hives survive at one, and 12 for 12 at the other one. The last result was a pleasant surprise. How different from my problem site. No problem with stores here. The overall quality of the clusters was pretty good. Only one micro cluster. Most of these have survived at least 2 winters. My oldest living hive system made it through their 5th winter.
 

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So it looks like spring has finally sprung. With the winter breaking I managed to look at all my sites over a couple of days.
Thanks for the update, LHarder. I am impressed you are able to manage that many hives. With just a couple hives and setting out swarm traps, I already feel quite busy this Spring. Best of luck to you in the weeks ahead as the weather hopefully turns the corner.

Russ
 

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Discussion Starter #377 (Edited)
That is part of the learning curve. Dealing with some numbers. Isn't the number about 300 full sized hives that one person should be able to deal with? I'll be starting another 100 nucs this year (this year compressed to 2 rather than 3 months), putting in another spring site, with maybe a goal of about 150 full sized hives next year. All this so I have numbers to work with and be a local dominant player genetically. I'll be furiously making top and bottom boards the next while, checking for food regularly, setting up a site, a bit of spring sampling. All sorts of efficiencies are needed. And that's not all. Other things are afoot that I can't talk about yet...

We are getting some decent flying weather 15 to 17 C in a couple of days. Things are changing fast.
 

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Discussion Starter #379
I have all bear fences activated now. For my Heffley sites where my 2 year old colonies reside, I did some cluster assessments which I can match with my late summer brood mite counts. 6 of 21 surviving clusters had 3 frames or less of bees. 2 micro clusters. The rest were mostly in 1 full box with an occasional 2 boxer. My longest surviving colony that struggled out of last winter is now gang busters again. I had 2 colonies that I was unable to take brood samples because there wasn't a sample to take that are in at least one full medium box of bees, one with 2 boxes. Last fall I had one have with no brood whatsoever that I assumed was queenless and doomed. I took their honey and doomed them. Now I am wondering if I killed a hive particularly good at a brood break. 3 of 4 with 20% plus mite counts were still living, 2 on 2 or 3 frames, but one with 2 boxes of bees. Meanwhile 2 of 3 hives with very low counts survived, in 1 box clusters. I won't go on with this preliminary analysis, but suffice to say mite count is not tightly correlated with survival. Not for this group of hives. None the less I have a few nice low mite, nice spring cluster hives to work to make queens from this year.

I think I may be seeing evidence of a brood break and mite cleanup for some hives. Perhaps the timing of the break is slightly different for different hives and this causes error in my results. Just throwing that out there. Future sampling will resolve this. I also will do a few spring samples to compare spring mite counts of those hives with low counts in the late summer with those with high counts.


I was going to start helping some small clusters with some bees, then decided why would I jeopardise valuable queens with manipulations at this stage. The micro clusters will have to wait for help at this point.

I think at this point we can see how completely unnuanced world view we have about mite/bee/virus interactions. There is so much to learn from untreated bees.
 

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Seeing the quote about equalization reminded me of the 2 Keith Delaplane lectures I've seen recently.

Dr. D, who heads up the UGA bee lab, has a grant to study polyandry, and is excited about the new project. I'm not going to steal his thunder and I don't have access to his slide-deck, but one of the discussion points talked about during his lecture was how equalization can mimic the effects of polyandry (multiple mating).

So, the research shows that queens who mate with more males have generally better outcomes... better growth, better pest resistance, better disease resistance, better foraging. So, unless we artificially inseminate, how do we make sure our promiscuous queens mate with 30 dudes? (Anyone answering "buy them a drink" will be banned by Squarepeg for a week... I'm just saying... don't do it)
Thanks
Mike
Mike, What if you had 2 queens with 10 patra lines each. Make several daughters of each in their own Apiary, All normal stuff to this point. Now put one of each line into the same "Hive" , a 2 queen setup. I ran 2 queen setups in the 80s it was big fun, too big, scary at times, so I backed out of it. Often had 4 deeps of brood and 10 supers, but it was with more prolific queens. if the Ankle biters and the VRSH line are less prolific maybe a 3 medium brood, with 8 supers and a 2 medium brood on top would manageable. I have a couple long double deep hives I may try this in this year. Start one at each end. the long hive takes the height issue out, so that takes one of the worst issues away. I personally am not keen on moving brood from hive to hive in the whole apiary, Seems fraught with other "features". 2 Different patra line queens put together making a "super organism" seems a good test/compromise.
GG
 
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