Varroa, many faces, one mite.

[Van, Arkansas, USA]

I was taught when addressing the public NOT to use scientific words, that I would lose 10% of my audience for each scientific word I used.  So, no scientific words.  I realized from reading many post on this forum and the web in general that individuals do not realize the many faces of varroa.  Not all varroa are the same.  Some mites reproduce much faster in one location compared to another.  I am not taking into account weather or many other external factors.  I wish a person to focus on a given varroa mite, all things being equal, some varroa mites are much deadly than other varroa mites.

Varroa has many different strains, maybe 100's maybe 1,000's, no person knows.  A strain is just a slight variation within an organism.  Understand the flu, most of the time it's the same virus, but a different strain therefore we as humans are literally plagued with the flu virus year after year that is basically the same flu virus,  just a different strain.  I am speaking in general here for simplicity.

One strain of varroa can be totally different from another.  In 1918, the Spanish flu infected 500 million people, killing approx. 10 million people.  The very next year, same flu, different strain no significance.  Well varroa has many strains, some much more deadly than others, but in every aspect varroa.  I believe this accounts for the bee keeper that had managed hives for years, treatment free, to suddenly experience most of the hives dying.  I contend the bee keeper did nothing incorrect, that a highly invasive STRAIN of varroa entered the hive.

I used to maintain strains of a very common bacteria that caused skin infections, 1,800 different strains of the exact same bacteria, some deadly, some produced only minor skin infections.  Some strains carried the ability to produce some very potent poisons.  If I apply these facts to varroa, on a more likely than not basis then varroa can vary as much of a difference between strains (individuals) as the deadly Spanish flu to common flu.

I am not talking differences within a given hive, rather differences between apiraries.  So when a beek discusses varroa and a given situation that varroa may be particularly invasive or have the ability to reproduce much faster than conventional mites.  Please, if I have caused confusion, please, please let me know and I will try to better explain.
Blessings


Dont worry about reading further.
OK, remember I stated no scientific words;;;;  Well forgive me on this paragraph, I must clarify some general issues or my shadow is going to pain me.  I am discussing Varroa destructor sp.  Due to limited research funds on a world basis, currently virulence factors between strains, even selective genetic markers of conserved regions for species differentiation is not well studied with Varroa destructor.   Phylogenetic analysis although well studied in Apis mellifera is not comparable within Varroa destructor genome bank.  Thus individual virulence factors, virion contribution, or selective environmental pressures are not well understood withing this relativel newly introduced mite circa 1995.  This text purpose is to explain variability of mite virulence on hopefully easy to understand format. 

[gww]

Van
I would be the essential defanition of lower then a layman.  No back ground of the subject matter at all.  Is it really the differrance in the mite that has to do with collony colapse?  I can see where a faster breeding mite might spread a pretty benign virous maby wider where it might effect more bees and have a bigger effect but isn't it true that it is not really the mite that kills the bees but the virus it vectors?  So it would seem that the virus would be the thing that might be differrent for what ever reason and the reason for differrent end results.  Does the mite really make the differrence?  I have no background and don't understand much that I read even when trying.
Your thoughts.
gww

[Eric Bosworth]

Mites are parasites. Even if they don't kill the bees themselves and the viruses they carry do they still suck the life out of the bee. If for no other reason than adding extra baggage to carry around foraging.

Sent from my SAMSUNG-SM-N910A using Tapatalk

[Van, Arkansas, USA]

GWW, not all varroa mites carry viruses.  I am pondering the mite saliva, not much known.  Like a mosquito injects salvia into the flesh to prevent clotting of blood.  Mites must over come clotting by the larva and/or bee by some means.  In predator insects such as the robber fly, the salvia is very toxic.  Well a mite could do the same.  The salvia in different mites could vary greatly in toxic effects on the bee in larva or adult stage.  Salvia is just one of many avenues a mite could produce real serious problems.

Some insects such are the dreaded but common red bugs have such soft mouth parts they cannot penetrate human skin.  To overcome this inability, red bugs throw up a skin dissolving liquid then lap up the liquidified skin.  Gross I know, sorry, but I am trying to show varroa can by various mechanisms obtain bee blood and those mechanisms can very from mite to mite and are not well studied.  The feces of mites could have effects on the bee brain or antennae disabling the bees ability to dectect and remove mites.  I could go on and on.  If I add virus, then things get complicated fast.  Virus in humans can transmit genes that code for cancer.  This is well understood.  No telling what all could be transferred to varroa besides Wing defomatity

Some common bacteria such as E. coli have zero ability to produce endotoxins, (poison) yet I have worked with E. coli strains that had the ability to produce 8 different toxins.  A difference of life and death for one infected.  These toxins can be stronger the the poison of a coral snake.  The exact same species, one strain acquired the ability to produce endotoxins, the other did not.  BTW, again virus transferred the ability for E.coli to produce endotoxins, and sometimes antibiotic resistance.  As I said, if I add virus to mites very bad things can evolve randomly. 

Eric:;; ditto ditto ditto.  Blessings

[gww]

Van
But it is now being said that mites don't eat bee blood.  They eat bee fat.
Cheers
gww

Ps some studies have shown that the mite hides due to absorbing the smell of the bee in the hive and if transfered to a bee in a differrent hive it is a very small window that the bees might detect the mite before it takes up the new smell of the new bees.

[little john]

But it is now being said that mites don't eat bee blood.  They eat bee fat.

Strictly speaking, bees don't have blood (or a heart, arteries, veins etc), but their bodies are filled 'wall to wall' with haemolymph instead.  Within the abdomen there is some kind of fat storage body (analogous to our liver) about which very little is currently known, but undoubtedly the 'fat' which the Varroa mite ingests will be in the form of lipids (liquid fat) present within the haemolymph.
LJ

[BeeMaster2]

 Van,
Here is a question that I have had for years but never knew who to ask. Maybe you will know.
When an female mite enters a brood cell, it first lays a male egg and then it lays female eggs. So a female mite always mates with its brother. If that is the case then all mites would have the same genes with the only difference being caused by mutations. Is that correct?
Jim

[little john]

Hello Jim - the idea of an organism "having the same genes" - although reasonable at first sight, turns out to be something of a simplification ...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5089174/pdf/nihms-790181.pdf  is a fairly recent paper (2016) - and I think the wording of their conclusion is very telling:

We found that existing microsatellite markers in V. destructor display unanticipated levels of diversity, in contrast to the limited diversity we would expect given historical bottlenecks, haplodiploidy, brother-sister matings, and previously reported diversity within North America. This variation may help explain how a species with such low genetic diversity can nevertheless evolve acaricide resistance and spread rapidly wherever it has been introduced. We still know little about the mechanisms and magnitude of V. destructor transmission, which is a key parameter underlying parasite dynamics.

So there remains a huge 'don't know' with regard to Varroa mite genetics.  Trust this will help to muddy the waters ... <wry smile>
LJ

Forgot to mention - sometimes (apparently) two or more foundress mites enter a brood cell at the same time - so some outcrossing then results.

[Van, Arkansas, USA]

Yes, Mr. Jim.  Varroa offspring are inbreed as you correctly stated.  However, in the male mite, rearrangement of the genes is possible.  In male humans, the process of gene rearangement is called PRIMARY NONDISJUNCTION.  When genes rearange, this can completely alter the basic genetic composition and subsequent expression of the genes.  So, negative bad genes, lethal genes, when duplicated in mite eggs can be rendered harmless by rearrangement within the male mite.  I do not believe there is much studies in mite genetic make up as compared to other species, such as the honey bee.

Mutations as you correctly stated can also alter the genetic outcome.

[BeeMaster2]

Thanks Van.
Jim

[little john]

Van - does a similar rearrangement also occur in honeybee spermatogenesis ?  LJ

[Michael Bush]

>So a female mite always mates with its brother.

Usually, but not always.  Sometimes several females enter the cell and each lays a male.  It does appear that there is less outcrossing than on most sexually reproduced species so I would suspect that the genetic variation is much more limited but there is some outcrossing.

[Van, Arkansas, USA]

Sir Lil John, hey buddy.  You ask an interesting question. See following 2017 Journal of Zoology:

Distribution and variability of deformed wing virus of honeybees (Apis mellifera) in the Middle East and North Africa.

In this research, 311 honey bee samples from 12 countries were analyzed specifically to determine the genetic variability of the Deformed Wing Virus.  To my surprises the virus sequences varied from region to region, but specific within a region.  My GUESS the genesis of DNA variables within the honeybee is due to factors as I discuss in detail above about the mites.  In other words, the Genes are randomly scrambled most likely within the male.
Blessings

[little john]

My GUESS the genesis of DNA variables within the honeybee is due to factors as I discuss in detail above about the mites.  In other words, the Genes are randomly scrambled most likely within the male.

Hi Van.
Thank you, my friend.  I was rather hoping you might say this, as it's also been a guess of mine - albeit without any evidence whatsoever to back it up.

If it were to be proven that drones are indeed a potential source of mutations, then this might go some way to provide an explanation for the tremendous amount of effort and energy expended by mature honeybee colonies in creating and supporting such large numbers of otherwise enigmatic creatures.
LJ