Oxalic acid

[rink123]

Does Oxalic when trickled damage the Malpighian tubules (kidneys) of my bees and shorten their lives. ? if so how short

 

[drstitson]

Certainly damages developing bees and probably adults too. hence the once a year application (so that HM only gets 1-3 doses max).

However the beauty of bees is that they don't need to live long! so long as you don't kill them all immediately the next gen will be fine (and hopefully varroa and virus free)

You're aiming to succesfully treat the super-organism whilst damaging the component organisms.

 

[Finman]

.
Researches say that Spring build up is as good as non treated. All winterd bees will be dead before next summer.

It violates larvae badly.

No one has asked, does mite hurt bees.

However, queens live normally their 3-4 years even if they get 2 treatmens a year.

.

 

[For want of a better word]

Does Oxalic when trickled damage the Malpighian tubules (kidneys) of my bees and shorten their lives. ? if so how short

If you kill your old queen slowly she will be superseded eventually, if she dies soon after the trickle on the bloodless colony due to stress from the oxallic you simply loose the lot!

But vaporisation of oxalic... although more complex to administer, from what I have read, does not damage the Malpighian tubules.

Seems to still be a lot of confusion around concerning the use of oxalic acid

 

[Finman]

.
ICAN, STOP THAT CARBAGE!

Use your evaporator but stop bullshit!

 

[For want of a better word]

.
ICAN, STOP THAT CARBAGE!

Use your evaporator but stop bullshit!

As I said.............

Seems to still be a lot of confusion around concerning the use of oxalic acid

​

and Aunties not going to be happy when she finds out the evaporator exploded!!!!

 

[Finman]

.
Hey small boy!
How many hives you have and how many years you have experience about varroa?

What is your preference. Vaporazing is at least 20 years old method and very few use it.
It has been doomed tens of time.

I am not confused. i am here shooting down stupid ideas.

 

[gavin]

 

[For want of a better word]

I can see some New Year resolutions being broken here!

I will agree to differ

 

[Finman]

.
You think that advices about bee diseases are something pop corn thing.

You invent problems from your own head and resolve serious things from your ownhead.

I have met those guys enough during my work life. Great egos!

 

[Bee-Key-Pur]

Ello Ello, what's goin on ear then. There's nofin to see, so move along please...

 

[boca]

Does Oxalic when trickled damage the Malpighian tubules (kidneys) of my bees and shorten their lives. ?

According the studies I read bees ingest some OA solution, which damages their internal tissues, especially the malpighian tubules.

But vaporisation of oxalic... although more complex to administer, from what I have read, does not damage the Malpighian tubules.

Since they cannot ingest the OA crystals, this statement seems logical to me.

However it does not mean that the sublimated OA harms less. It is difficult (or impossible) to quantify the harmfulness of a treatment. It is easier to measure the immediate benefit.

One of the disadvantages of the sublimated OA in my opinion is that it covers every surface inside the hive, even where it is not needed for varroa. The hive is not a box where only bees and varroa live together. There are (or could be) other organisms (mites, insects, fungi) beneficial and not.

I compare sublimation to spraying a pesticide from an airplane, trickling is like the seed treatment.

 

[Finman]

.
I just read a research made by Allian &Ellis 2008 Usa.

Raport says they found 6 days after trickling small droplets in the hive. They conclude that bees does not suck actively oxalic syrub.

The reseach handles how contact bee to bee aids the movement of trickling syrup in the colony.

 

[Hivemaker.]

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Raport says they found 6 days after trickling small droplets in the hive. They conclude that bees does not suck actively oxalic syrub.

Just bouncing this back to the thread from a few days ago.


Post 23 From Gavin.

That is one of the least accurate posts I've seen on oxalic acid.

Larvae get fed with the secretions of workers, and so are not directly exposed to solutions poured on the workers but buffered by the internal physiology of the worker. Furthermore I've never known a larvae to reach out of its cell and groom a passing worker so it will not be over-exposed through that route either.

Workers ingest oxalic acid. Whether this is by imbibing syrup or grooming doesn't matter, it gets inside them. When these Spanish researchers dosed bees with 10% oxalic acid solution (greatly in excess of normal treatment levels) they saw various effects on internal tissues of bees, essentially the degeneration of tissues.

http://revistas.inia.es/index.php/sjar/article/viewFile/270/267

The implication of all of this is that the haemolymph is affected, and that may be a route that affects Varroa. It would certainly explain the often slightly delayed effect on Varroa.

The paper looked for and explicitly declared a lack of visible lesions on the exterior of treated bees (see Fig 2).

And post 27.

Just to make it easy, I'll post some text from the paper. Technobabble warning, but it is clear enough. None of this will stop me from using oxalic acid. The 100+100+7.5 (aka 4.5% aka 3.2%) recipe is more dilute, and the small loss of bees (or reduction in vigour) is more than made up by the effective Varroa control.

G.

----------------------------------------------------------------------------------------

Images from the SEM did not show any change in
the external surface of treated bees although a white
deposit could be seen on test bees (Fig. 2). Gross lesions
were not observed on external structures or internal
organs. There was higher fragility while dissecting the
digestive tube and the Malpighian tubes in bees killed
after 48 and 72 h but not in corresponding control bees.
Pathological changes were present in epithelial layers
covering the ventriculus, the rectum and the Malpighian
tubules of all bees killed 24 h post dosing. Lesions were
more severe in bees killed at 48 h and even more severe
in the 72 h group. No alterations were seen in control
bees. Some variations were seen in control and test bee
hypopharyngeal glands. This was probably due to tech-
nical problems and therefore is not included in this study.
At the microscopic level, the epithelia of the ven-
triculus appeared to have a degree of hydropic degene-
ration including the presence of multiple vacuoles
around the nucleus in bees killed at 24 h after treatment
(Fig. 3B). Cytoplasmatic structures were altered after
48 h especially in the regeneration crypts (Fig. 3C). At
72 h, the mucous layer was severely injured. There were
wide denuded areas or zones a few cells with a picnotic
nucleus could be seen (Fig. 3D).

Cells from control bees had an eosinophilic granular
cytoplasm without vacuoles (Fig. 4A). Lesions in the
rectum at 24 h after treatment were similar to those in
the ventriculus but were to a lesser degree (Fig. 4B).
Mucous cells had slight hydropic degeneration with
cytoplasmatic tumefaction due to small vacuoles. At 48
h more severe cellular damage was confirmed by the
dilution of organelles. Part of them could be seen close
to the nucleus, which usually appeared in the basal area
of the cell (Fig. 4C). Seventy two hours after OA adminis-
tration cells had a polygonal morphology, the cytoplasm
was optically empty and the nucleus picnotic displaced
to the basal area («ballooning cell»), which showed the
maximum level of alteration (Fig. 4D).

Malpighian tubules were also affected from 24 h.
Initially a small supranuclear vacuole could be seen
while the cytoplasm was similar to that of control bees
(Figs. 5A and 5B). At 48 h, the cytoplasm appeared
tumefacted (Fig. 5C), but it was not until 72 h that several
small vacuoles in the cytoplasm and picnotic nuclei
were present (Fig. 5D).

http://www.beekeepingforum.co.uk/showthread.php?t=14938&page=3