Varroa

[Finman]

.
When we look varroa problems in warm countries, wher brood is present a year around, varroa control is very difficult.

If formic acid affects under brood caps, the control would be just a piece of cake. but...

 

[itma]

Just in case anyone should be in any doubt that Formic DOES have the ability to kill mites in capped brood cells ...

... In this study, a 17-h application of 50% formic acid effectively killed mites in capped worker brood and on adult bees without harming queens or uncapped brood. ...

"Short-term fumigation of honey bee (Hymenoptera: Apidae) colonies with formic and acetic acids for the control of Varroa destructor (Acari: Varroidae)." (2008)
http://www.ncbi.nlm.nih.gov/pubmed/18459386

 

[Finman]

Just in case anyone should be in any doubt that Formic DOES have the ability to kill mites in capped brood cells ...
]

Text continues "The short-term formic acid treatment killed > 60% of varroa mites in capped worker brood; thus, it is a promising tool for beekeepers, especially when such treatments are necessary during the nectar flow."

Lets calculate:

we have 1200 mites in a hive and 1000 are under cappings.

After treatmnet hive has 400 mites.
- next month 800
- next 1600

.
What I understand from Canadian treatments, in practice formic acid efficacy is sometimes 70% and sometimes carefully done in bloodless hives 96%. A large fork.

 

[Finman]

.
Argentina

FRIES (1995) recommended formic acid treatment with average temperatures between 12 oC and 25 oC and with optimal results between 18 and 25 oC.
WILSON & COLLINS (1993) demonstrated that formic acid is not effective for Varroa control in hot climates (between 20 oC and 32 oC).

Though temperatures within this range were registered in Aguilares during part of sampling period a high percentage of efficacy accumulated was registered (average 92%). A similar situation was observed in previous studies of these authors (EGUARAS et al., submitted).

Though significant differences were not detected between dispenser position in the colony, those treatments that considered an homogeneous distribution of formic acid dispensers showed a greater effec-tiveness. This agrees with FRIES (1989) who said that one of the principal causes of formic acid low efficacy was related to distance from dispenser to brood area. In this sense, ROSENKRANZ (personal communica-tion) observed that mite mortality inside the cells depended on dispenser position. In this way, when dis-penser was put over the combs a great proportion of dead mites was found in the upper half of brood comb; the other way, a high proportion of mites inside cells located in the inferior half of the comb survived. It is probable that this fact could explain variability between colonies in formic acid treatments, and a homogene-ous distribution of formic acid in the colony does not take place because of partial location of dispenser.

 

[itma]

He believes who believes, but there is no stuff which kill mites under cappings.
That is pure propaganda. Company has advertised the stuff over 10 years that it affects under cappings.

Well in 17 hours, you can kill 60% of the mites under cappings, and in the Argentine paper they showed 92% average "efficacy", and another paper * records 89% mite kill in capped brood cells after 96 hours (4 days).

So there is stuff that kills mites under cappings.
It is called Formic Acid.
Temperature, duration and application method may alter the efficincy, but be in no doubt -- 'there IS stuff which kill mites under cappings'.
Not propaganda. It does affect under cappings.
And that would go for the MAQS formulation of Formic Acid as well.


* - that other paper: "THE SURVEY OF FORMIC ACID EFFECTS ON VARROA MITE VARROA DESTRUCTOR A.&T. IN SEALED BROOD CELLS OF HONEY BEE" (2003) http://www.sid.ir/en/ViewPaperprint.asp?ID=34874&varStr=

 

[Finman]

Mohammes said: trust on God, but tie kamel first

To me "kill" means 96% dead rate.

if you have 1000 mites,

- 96% is 40 mites are alive
- 90% efficacy means 100 is alive
- 80% means 200 is alive



-

 

[Nige.Coll]

i'll probably get a public stoning for this but...

if your in a real mess at this time of year and it's turning cold wouldn't oxalic sublimation help . it wont damage any bees or stop them laying and the temp is not an issue. a few treatments of that and the mites would take a real hammering.
it could get you out of a pickle.
you would just have to be careful you don't gas yourself ofc as it's not nice for humans.

 

[Finman]

i'll probably get a public stoning for this but...

if your in a real mess at this time of year and it's turning cold wouldn't oxalic sublimation help . it wont damage any bees or stop them laying and the temp is not an issue. a few treatments of that and the mites would take a real hammering.
it could get you out of a pickle.
you would just have to be careful you don't gas yourself ofc as it's not nice for humans.

It is true.

When day temps dropped under 10C in September, since then I have trickled all my hives with oxalic. Most of hives have yet some brood.

At the end of October I make second treatment.

 

[Nige.Coll]

i was referring to the vaporization of OA really not trickling .
it could be a way of saving the colony or at least reducing the varroa considerably in a short time.
just have to be careful doing it.

 

[Skyhook]

I've heard that multiple applications of OA can cause harm. I've also heard that it's safe. Until I'm sure which it is, I try to avoid multiple applications in a season.


.

 

[Nige.Coll]

multiple treatments using the trickling method can be harmful.

 

[masterBK]

Turkish researchers using two applications of oxalic acid 10 days apart did not find any toxicity problems.

http://journals.tubitak.gov.tr/veterinary/issues/vet-09-33-4/vet-33-4-4-0712-16.pdf

 

[For want of a better word]

i'll probably get a public stoning for this but...

if your in a real mess at this time of year and it's turning cold wouldn't oxalic sublimation help . it wont damage any bees or stop them laying and the temp is not an issue. a few treatments of that and the mites would take a real hammering.
it could get you out of a pickle.
you would just have to be careful you don't gas yourself ofc as it's not nice for humans.

Simple easy to do and high level of efficacy.

 

[Finman]

multiple treatments using the trickling method can be harmful.

Old knowledge.

 

[mbc]

multiple treatments using the trickling method can be harmful.

As can single treatments.

 

[Finman]

As can single treatments.

Yes lethal to mites but not to bees or queens.

You do not need to use oxalic trickling but please, don't deliver carbage.

Recommended treatment methods has been researched by best experts during years 1988-2003.



but believing continues...even 10 years after the results.

.

 

[mbc]

Yes lethal to mites but not to bees or queens.

You do not need to use oxalic trickling but please, don't deliver carbage.

Recommended treatment methods has been researched by best experts during years 1988-2003.



but believing continues...even 10 years after the results.

.

I take it from this post that you believe an oxalic trickle has absolutely no adverse effect on the bees ?

 

[Finman]

I take it from this post that you believe an oxalic trickle has absolutely no adverse effect on the bees ?

Oh dear....not again...
Take as you like. It has no meaning.

 

[The Drone Ranger]

Hi Jimmys Mum
Although Apistan is not as effective as it was it will still take down mites without side effects on the bees
It is not temperature dependent and acts over a full brood cycle
you can combine it with other treatments like thymol or oxalic
The hive will probably die out but you never know

 

[Nige.Coll]

Old knowledge.

it may be old knowledge but isn't old knowledge called wisdom ?

i do not want to drag this thread off topic i was only hoping to give some advice and save the op's bees