Resistant bees, productive or not

[Ted Kretschmann]

I post this thread because I had developed a bee that was varroa mite resistant. This line was later incorporated for the genetics into other resistant lines that have been developed. The problem was the bee that was developed lost the ability to produce the really big crops of honey that honey producers so depend on to make a living. The bees maintained smallish colonies and produced crops in proportion. It turns out that a lot of the resistant lines of bees (russians) do not produce as good a crop of honey as some more susceptable bees. This has been documented and studied. So is it better to have a bee that requires some treatment but produces big crops and stays alive because of the treatment. Or is it better to have a totally resistant colony that produces smaller crops and the cost of the treatments remain in the beeks wallet. Keep this civil, I did not post this to start world war 3 TED

[sqkcrk]

This is the same thing that happened back in the 1950s when Walter Rothenbuler, then of Iowa and later Ohio, developed a strain of bees that was as totally resistant to AFB as it could be. They didn't produce much honey.

What we need is a strain in the middle, I guess.

Is it possible to start w/ the varroa resistant stock and develope it into a more productive strain?

[hpm08161947]

I post this thread because I had developed a bee that was varroa mite resistant.

Ted... How was your bee able to resist the varroa mite. Did it pick it off itself or others? Or was it just not attractive to the mite... some how. Just curious...

Herb

[StevenG]

Ted, my best producing hive last year was a B. Weaver strain, and it produced 60 pounds of surplus. It had swarmed, and wasn't a very good season. My total production from 16 colonies was only 500 pounds. I've been expanding colony numbers, and not as concerned as I should be for honey production. Weavers say their bee is a good producer. I certainly hope to find out this year.

Sounds like we're talking about the Holy Grail of beekeeping: A bee not needing any kind of treatment for mites, vast honey production, and (shall we throw in) gentle enough to be worked in a t-shirt (veil optional)?
Regards,
Steven

[WI-beek]

AHB is varroa resistant and produces huge crops from what I hear/read so it must be possible to have the best of both worlds unless that means mean bees.

Maybe it is just that we have not found the right resistant trait yet. If we could get bees that would actually pick off the mites and chew off their legs we would not need genetics that waste brood, and keep small winter clusters, breaks in brood cycles, etc. I actually find it strange that the bees tolerate the presence of varroa on their sisters. You would think they would be persistent in harassing and chewing on them. It must be that once the pest is on the bee they dont see it as a threat. They keep a constant guard on shb so why not varroa?

[Ted Kretschmann]

According to Dr. Danka of Baton Rouge. The bees that we bred were SMR type bees. They have something in their saliva that retards the Varoaa mites growth. So when the adult bees feed their larvae. The substance gets into the brood food and makes the larvae unattactive. This is a recessive gene. We acheived it by a closed population of fifty colonies over seven years. Hives that did not die in the winter were split in the spring to replace the loses. They were allowed to raise their own queens and back breed in among themselves. While we bred a resistant bee, it was worthless for honey production. The crops were too small and the colonies were too small in numbers. So there is a trade off. You sacrifice something to get something. In this case, resistance for honey production. The very best of the colonies we had went south donated to Baton Rouge. They were used along with other Beekeepers bees to develope some of the resistant lines that are in use today and soon will be in use at a later date. So we go full circle- a resistant bee or one that produces good crop that need some treatment?? TK

[Ted Kretschmann]

Wi, I know that there have been studies on this...The researchers did mite count drops. They looked at the mites. Many of the mites HAD BITE marks on their shells. So our EHBs do try to pick them off. It is a dangerous place for a hitch hiking mite on the back of a bee. It is much safer to stay in the capped brood cells. TK

[rrussell6870]

Ted, you are hitting the nail directly on the head! There are 3 different ways to develop resistances in your stock...

1. Let everything die and breed from whatever makes it... losing nearly everything and running a life-long risk of inbreeding...

2. Cross breed with a strain (ie.. russians) that are far from acclimated to your environment and if you make it past the first 5 gens of angry bees, you then have to face the late buildup and tiny clusters that kill production in most of the US...

3. Take care of the stock that you have, continuing the countless generations that have been selectively bred for production in your climate, and wait for the bees to build their resistances...

They are already doing it... if they were not, there would be NONE left in those operations chose option #1 above.

I keep hearing people talking about 50-70 lbs per hive... They must have no idea what the average was like before mites... I have been concerned that a mixture of poor breeding practices, and an over use of "breeder" queens from too few suppliers may have a lot to do with the drop in average production across the board.... But then I started to consider a different issue... As the years progress, every strain of bee is building more and more resistant to varroa... that means that each strain of bees is developing VSH traits and possibly higher swarming tendencies... this could very well be a big part of the average production rates decrease...

Now on to the issue with VSH... As I have said before, "Too much is Too much"... a 100% VSH colony is not nearly as productive as a good old italian or even the AMM...

Russians are so resistant for several reasons... the most obvious is VSH behavior, the second is multiple swarms per season... breaking the brood cycle often, and then in winter for a prolonged period of time...

VSH is a very useful trait... but it has to be balanced within the population of the colony... VSH is a recessive trait, so both the queen and the drone must carry it for the worker to express it... each VSH drone that a VSH queen mates with will produce a certain percentage of VSH workers within the colony... Too many, and you lose production... Too few, and you lose resistance... Now for this to be controlled within a major operation is very hard...

Thoughts?

[rrussell6870]

It is a dangerous place for a hitch hiking mite on the back of a bee. It is much safer to stay in the capped brood cells. TK

Exactly... That is where the heart of the issue lies...

I know of a few studies that are going on to test the theory of causing sterility and other issues within the mites themselves... may be a winner, may be another disaster waiting to happen... who knows... It may end up causing varroa to mutate enough to start living on humans. lol.

I think that varroa are soon to be a pest of the past, and production and SHB will be the next big hurdles...

[Ted Kretschmann]

Robert, I had hoped you would chime on in. I finally chose method number three, many years ago on the advice of Dr.Shimanukii. Keep treating until the bees as a general population caught up with the problem. The problem is by doing that with a commercial operation. You reproduce the bees using their own genetics aka splitting and letting them raise queens. You eventually have to bring in new blood periodically to reduce the chances of inbreeding. If you do not then you end up with my closed population experiment BUT on a GRAND scale--a whole outfit of non productive bees. Before mites we had, correct me Russell if I am wrong, 850 matriachal lines that breeders could breed from. Now, I have been told it is something along the line of 39. The mites wiped out vast pools of genetic material. So with that in mind, it has been a little over two years since I brought in several hundred Aussie queens. Those bees were two years out from Europe. Thus it is time for some more new genetics to sprinkle around the outfit. So Robert, I have no Mississippi genetics, that is one of the 39 remaining american lineages that I have no genetics from. So you know what that means.--WHEN CAN I PLACE AN ORDER<<< TK

[rrussell6870]

You have the right idea... Thats why it has been so important to teach people to NOT use the "let em all die and breed from the few that remain" method... all this does is wipe out lineages that we cant get back... sure they may not have progressed in resistances as quickly as the others, but they were light years ahead of the resistant lines in production and gentleness.

I work terribly hard to bring in new lineages from outside of the US each season... but its a heck of a process... we quarantine them for years, and study, study, study, before we ever expose them to the mainland... this is a cycle that has to be fed each year, otherwise you end up with a few years of an empty island and a ton of money wasted...

NZ has got some great production lines and seriously gentle stock...

As a nation, we have to "reboot" so to speak... lots of folks have great bees... but just how long will it stay that way...

I will say that one method for keeping the lines more productive is to select your worst 10% of colonies from each yard each season, and requeen with outside stock... One supplier each year, but rotate the out each year... this will add more lines back to your operation and limit expenses stop this process after 6 years... wait 6 years, then repeat this process again... this will cut the costs, keep your own lines going and keep a diverse enough mix that you wont get stuck back-breeding.

PS, Dont worry about ordering, I already have you down for some SunKists, English Buckfasts, and some of Bill's old Mountain Grey Caucasians...

[JBJ]

TK how good was the honey production in the foundation stock you developed your resistant line from?

The degree of physical genetic linkage between traits for honey production and mite tolerance should be possible to determine. With the honeybee genome now sequenced this would be an interesting study. I would bet the traits are not as tightly linked as some suggest.

Did you find it possible to select for production amongst your most tolerant lines?

[sevenmmm]

Fascinating.

I have ordered Russians from 2 sources and Carniolans to mix. If I worked these together, assuming the mix works, at what point would this be considered a new strain?

[sqkcrk]

I would bet the traits are not as tightly linked as some suggest.

If, the heritable trait of house cleaning ability is linked to honey production, as it seems it is, from what little I know of Rothenbulers study, wouldn't it make some sense to think the same may be so for mite resistance? If that mite resistance is expressed thru the bees grooming the mites off of fellow bees?

Is the bees getting rid of mites manually, or should I say orally, what constitutes resistance?

How is resistance expressed?

Tolerance is another question.

[Ted Kretschmann]

JBJ, The production was half of what would be considered normal for this part of Alabama. 70 pounds of surplus per hive is considered normal for Alabama--AM--After mites...So the resistant bees were only producing 35 pounds of surplus honey per hive. Thus we discontinued the experiment and turned over the best of the stock to the USDA. As it did have merit due to its resistance. TK

[JBJ]

The genetic architecture of foraging behavior and resistance/tolerance is quite complex and involves multiple traits on multiple chromosomes. The degree of genetic linkage between traits is a physical measurement. Given that my observations do not match TK's it would be very useful to the discussion to know these measurements.

Complex social behaviors can manifest themselves to varying degrees at the colony level depending on the exact mix of genetic fathers. For example, for a HYG or VSH trait to be expressed at the whole colony level, how many of the drones that the queen mated with have to carry this trait (10% 30% 50%)?

http://www.hgsc.bcm.tmc.edu/project-...is%20mellifera

http://www.genetics.org/cgi/reprint/141/4/1537.pdf

If productivity and resistance were truly tightly linked and inversely correlated one could simply select non-productive lines and produce bees that would show resistance, to the best of my knowledge this has yet been done. The right mix of genes in a specific cross should be able to provide expression of resistance traits and productive traits at the whole colony level.

Is there a geneticist in the house? How many centimorgans apart are these traits and on which chromosomes? Looks like the honeybee genome is downloadable (first link).

Would love to continue this conversation later, but now it is time to graft.

[josethayil]

The honey bee genome has been sequenced, but the genes for honey production, gentleness, varroa resistance ETC have not been pin pointed.

We know that they exist, but we dont know which ones are they. That is why we cannot progress in the field very fast.

If we knew which ones were they, we could have crossed bees which have genes for high honey production and gentleness with bees with good varroa resistance and look at the offsprings and see if they are present in the offsprings.

People are working on it at the moment, so hopfully in the near future we will know which genes represent which traits.

[BeeLee]

Just as an FYI, Marla Spivak tested the honey production, Varroa levels, chalkbrood and AFB levels of her MN hygienic line against a non-selected line. The produced significantly more honey, and had lower levels of Varroa and disease. The PDF is online:
http://www.apidologie.org/index.php?...3_ART0008.html

JBJ, the queen needs to mate with at least 50% hygienic drones for the colony to be hygienic.

Katie

[max2]

Just listening in here - we have no Varroa in Australia at this point. We have SHB and I'm constantly trying to pick up points to transfer a little of your vast knowledge - fascinating stuff.
Last year I averaged above 150 kg per hive, this year with the floods and all the wet maybe 1/2. With SHB I can loose a top performing hive in a very short time.Definitely interested to learn how the genetics can help. Keep talking!!

[rrussell6870]

The lowered productivity is not due to the genes so much as the mechanics of the vsh colony. As I have pointed out a few times before. The number of workers within a vsh colony depends wholly on the number of vsh drones that the vsh queens have mated with... to maintain productivity while implementing the vsh trait, there must be a balance of vsh / non-vsh traits. Colonies that express vsh traits in too many workers will have poorer productivity. Colonies that have too few vsh workers will have poorer resistance.

This is a complex issue for commercial producers and needs to be addressed especially as national production averages are suffering such a great decline.

Most honey production operations do not have the facilities to maintain such levels of balance within their colonies. It's a great topic and I believe many people could benefit greatly from the discussion.