Advice re varroa treatment

[Finman]

Finman
If OA has such a long lasting effect against mites then there should be no argument against using it over 3-4 cycles when brood is present.
Why do you think we haven't seen any research to confirm its effectiveness in this situation?

Look Dave Cushman pages.

I have seen results of these mite countings.
.
I woke up when one guy started to follow drop down.
Finnish experts gove to me their data and I have shown them in this forum many years ago.

It may be different thing, when acid gives its ifluence and when the violated mites die.
. Trickling syrup can be seen on bees' wings few days. Bees do not lick it.

.

 

[charlievictorbravo]

Data from Oxalic Vape and Thymol Treatments

I had a Varroa issue develop with one of my hives in July and started OA vaporising treatments. I aimed for 3 treatments 5 days apart, similar to the OP.

I checked the drop on a daily basis (the hive is at the bottom of my garden, so easy to do) and when I found I was still getting significant drops, I did another treatment or two. I then read on a thread here that OA continues to knock down mites after 20+ days so I left the 4th and 5th OA treatments for some time before losing my nerve and did another treatment. When I found I could not get the daily drop down to single figures I switched to a Thymol-based treatment and after 3 of these (at 14 day intervals) I am finally getting daily drops below 10 - today's was 4. I had a holiday for two weeks so I used the average calculated from the total drop over 14 days.

I have logged all of the daily drops and charted them on an Excel spreadsheet and I'm hoping I can upload it for the forum to see how various treatment produce differing daily drops.

Based on my rather poor attempt at making sense of OA treatment when there's brood, I would say some competent person/organisation should do some proper research on multiple OA treatments with brood - my effort on my 3 hives will not produce anything usable for policy making, only an indication that OA can be used with brood but may not be as effective as when used in a brood-less situation.

CVB

 

[Finman]

.
6000 mites. IT is wonder that the hive lives. But winter brood must be badly violated.
.

 

[charlievictorbravo]

.
6000 mites. IT is wonder that the hive lives. But winter brood must be badly violated.
.

I was probably a little late in starting the treatment - there was no sign of DWV and I monitored the mites for a couple of weeks when the daily natural drop increased in case what I was seeing was just a "spike" in the mite population. When the average over 10 days was high but I needed to acquire a supply of Apibioxal-OA which delayed things. There was probably a 10% infestation (10% of the bees had mites) at the start but as there was brood, some of the mites managed to escape the OA and breed, which is what the Thymol later mopped up.

My inherent target is to stay below 10 mites per day average - clearly, I don't have hygienic bees!

Colin

 

[TryingToLetThemBee]

.
6000 mites. IT is wonder that the hive lives. But winter brood must be badly violated.
.

I dropped 8,000 out of a colony in late Sept/early Oct of 2014 using Apiguard; the colony was fine.

 

[B+.]

My inherent target is to stay below 10 mites per day average - clearly, I don't have hygienic bees!

Indeed.

There comes a time when monitoring your colonies has given you all the information it can.

When faced with such a problem, I go back to my studies in Change Management. Conceptually, you have 4 choices:

1. Accept the situation as it is and do nothing different.
2. Change the situation.
3. Change yourself (not relevant in this case)
4. Leave the situation.

In truth, most beekeepers will choose option 1 or 2.

 

[TryingToLetThemBee]

there was no sign of DWV [snip] - clearly, I don't have hygienic bees!

Colin

SOMEBODY has DWV "B" though. I'll get ridiculed for this but it might be you.

 

[B+.]

SOMEBODY has DWV "B" though. I'll get ridiculed for this but it might be you.

Not if someone was actively selecting for a harmless virus.

Surely, by definition, a virus that shrivels the wing and reduces the life expectancy of a bee is a drain on the colony? IMHO, this is a red herring

 

[fatshark]

McMahon et al., 2016 Proc. Roy. Soc. B 283: 20160811
"Using laboratory experiments and a systematic field survey, we demonstrate that an emerging DWV genotype (DWV-B) is more virulent than the established DWV genotype (DWV-A) and is widespread in the landscape."

My emboldened text ...

 

[charlievictorbravo]

My understanding of the various strains of DWV, gained from this forum and links off it, is:

1. Type A DWV is the main killer of bees
2. Type B offers the bees some protection from other DWV types
3. Type C also kills bees but appears to be more dangerous to bees over winter and can be the cause of winter losses

I do not know whether the Type B has the same symptoms as the others and whether it will eventually kill the colonies - it certainly did not appear to do this to Ron Hoskins' bees in Swindon so maybe my bees and mites have Type B virus and I could risk a treatment-free regime.


CVB

 

[TryingToLetThemBee]

My understanding of the various strains of DWV, gained from this forum and links off it, is:

1. Type A DWV is the main killer of bees
2. Type B offers the bees some protection from other DWV types
3. Type C also kills bees but appears to be more dangerous to bees over winter and can be the cause of winter losses

I do not know whether the Type B has the same symptoms as the others and whether it will eventually kill the colonies - it certainly did not appear to do this to Ron Hoskins' bees in Swindon so maybe my bees and mites have Type B virus and I could risk a treatment-free regime.


CVB

Well hold on: I want no haemolyph on my hands!

But @B+. the whole point is it DOESN'T and we perhaps have more of a cowpox/smallpox type deal on our hands.

@fatshark : fascinating, thank you. I have always said we need to look to mite evolution (to less lethality) rather than bee (to more resistance) as being quicker. But viral evolution would be quicker still.

 

[B+.]

I do not know whether the Type B has the same symptoms as the others and whether it will eventually kill the colonies

I was coming at this from the position that a bee that has diseased wing (whatever the variant) is unable to fly and contribute to the honey yield of the colony (possibly even spreading the virus to larvae, thus increasing the number of bees infected).
Unless I have misunderstood something here, I don't think we want DWV bees at all. The different variants may be of interest to a virologist, but, how do they help beekeepers?

 

[TryingToLetThemBee]

I was coming at this from the position that a bee that has diseased wing (whatever the variant) is unable to fly and contribute to the honey yield of the colony (possibly even spreading the virus to larvae, thus increasing the number of bees infected).
Unless I have misunderstood something here, I don't think we want DWV bees at all. The different variants may be of interest to a virologist, but, how do they help beekeepers?

The burden of the @fatshark paper is that the original Ron Hoskins excitement is false hope, but the original argument is that a less harmful version (asserted it was "B") can grant colony immunity to the more harmful.

ADD link http://www.nature.com/ismej/journal/v10/n5/full/ismej2015186a.html

 

[Fusion_power]

If a colony has DWV-B, they do not develop the virulent form? My take on this is that any DWV variant is bad for the bees no matter what the circumstances. The bee may be up to the task of living with the virus, but it comes at a price.

1. Breeding for less virulent virus
2. Breeding for less fit mites
3. Breeding for bees that selectively kill mites

Of these three, breeding bees works. Virus breeding IMO is a red herring as noted above. Breeding less invasive mites is unproven and leaves the risk that one highly invasive mite could still get loose in the colony and wreak havoc.

 

[mbc]

I was coming at this from the position that a bee that has diseased wing (whatever the variant) is unable to fly and contribute to the honey yield of the colony (possibly even spreading the virus to larvae, thus increasing the number of bees infected).
Unless I have misunderstood something here, I don't think we want DWV bees at all. The different variants may be of interest to a virologist, but, how do they help beekeepers?

You're missing the point, type b is asymptomatic ie. no shrivelled wings, stunted abdomens and afaik no shortened lifespan.

 

[B+.]

You're missing the point, type b is asymptomatic ie. no shrivelled wings, stunted abdomens and afaik no shortened lifespan.

Unfortunately, I don't have the resources to search for virus variants so I can't select for something I can't measure. I suspect this is true of other breeders too.
When I see an asymptomatic colony, I look for other causes like their ability to manage varroa or the possibility of reinfection

 

[jenkinsbrynmair]

You're missing the point, type b is asymptomatic ie. no shrivelled wings, stunted abdomens and afaik no shortened lifespan.

IMHO, this is a red herring

In Prof. Steve Martin's opinion it is hygienic behaviour that is the red herring that has been drawing the hounds off the line the last few years.
They seem to be investing a lot of manpower and money world wide over something which has no bearing of a colony's ability to coexist with v.destructor.

Hygienic behaviour has nothing to do with Apis Ceranae's ability to coexist with varroa so why should Mellifera be any different?.

 

[Finman]

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Varroa was clearly easier 25 years ago than now.

. I do not mind about viruses, and are they B or C type.
I do not become smarter with that knowledge, because I cannot see them.

What I can do is to kill mites.

.

 

[B+.]

In Prof. Steve Martin's opinion it is hygienic behaviour that is the red herring that has been drawing the hounds off the line the last few years.
They seem to be investing a lot of manpower and money world wide over something which has no bearing of a colony's ability to coexist with v.destructor.

Hygienic behaviour has nothing to do with Apis Ceranae's ability to coexist with varroa so why should Mellifera be any different?.

Is it necessary for Apis mellifera to evolve the same mechanism that Apis cerana did? So long as it is effective, what do we care if A.m. developes a novel approach?

 

[jenkinsbrynmair]

If a colony has DWV-B, they do not develop the virulent form?

No they don't, in fact type B can wipe out type A