AFB questions

[BjornBee]

Questions are as follows.....

How long does one not see AFB in a hive treated with terramyacin?

Has anyone treated for active AFB, and then never treated again, and had no signs of AFB reoccurring?

Without growing a culture, can spores be seen or confirmed somehow? What power scope, etc?

How can a known hive with a past AFB history be used in breeding for AFB resistant bees? If a yard is kept isolated, what protocol or procedure would be good for AFB resistant breeding? I know others have bred for AFB resistance, such as Charkie Mraz, and the Minnisota hygienic line was known for this.

I am really sending balloons up at this point just searching for ideas and something to do? Any comments???

[Aspera]

This is NOT from personal experience, but here goes...

Once infected, equipment should always be considered infected no matter how careful apiary/hive furuniture is sanitized. Most hives (even those never diagnosed) probably have some level of viable spores, in any apiary. Culture is probably less than 70% sensitive when performed correctly on appearently healthy hives. Everything else is less sensitive and less specific. All tests improve when applied to apiaries known to have colonies recently infected. Strong colonies with highly hygienic keepers and can indefinitely surpress infection following 4 annual antibiotic treatments, but should probably be requeened with resistant stock. Spores of many Baccillus spp have been known to persist in the environment for >50 years. I do not know if this is true of AFB, but it is plausible. SMR stock will probably have a higher AFB resistance than the Minnesota Hygienics, but the crosses are much better producers. I would do the brood freezing test in preference to simply trying to select for AFB resistance. Unfortunately sometimes you may have to destroy equipment, or treat, or kill good queens, or all three. It seems like the disease is somewhat inevitable if you have bees for long enough. Trying to make a microscopic diagnosis is not a worthwhile endeavor without using a fluorescent antibody or some similarly riduculous procedure.

[ October 01, 2006, 11:22 PM: Message edited by: Aspera ]

[BjornBee]

Thanks aspera. I kind of knew most of that. I'm not sure where I am going with this. I question if an active hive of afb would be handy for testing procedures. Or is an active case, say a whole frame, too much for adequate testing of resistance?

Do people breeding resistant bees actually place afb comb into hives, and/or requeen active cases with supposed controlled afb resistant queens, ????

If a hive does not ever display afb again, although the spores are always present, what is the measurment of calling something "resistant".

I know if bees clean up afb before it gets to the active scale stage that it can be supressed. But is this just a factor of already known hygienic behavior that is already being bred for?

Does anyone have any research or published data on previous afb resistance breeding?

[Aspera]

Spivak, Taber and others have verified that colonies selected using the liquid N2 test are resistant to challenges with large numbers of AFB spores and even some brood. It is probably an unnecessary risk to do the challenges yourself because you can just do the freezing test with a sharpened can and N2, or cut out and freeze a section of brood.
I'm not sure is this is what you are asking, but freezing a whole frame of brood will not give you acurate results and may actually induce disease in an otherwise healthy colony by killing too many brood which will not be promptly removed.

[ October 02, 2006, 11:36 AM: Message edited by: Aspera ]

[mwjohnson]

Not trying to hijack your thread Mike...But need some advice along this line.

I learned this summer that a commercial beek has a yard(20-25 hives)about a 1/2 mile from mine.That's cool with me.

I have lived here almost my whole life,and never knew they were there,and weird thing is,hardly ever saw any bees until I got into it.

I was told that this guy has had(still?)an afb problem,and had marked those afb hives with a dot of blue spray paint,and keeps them seperated from the rest of his operation.

I guess it depends on who you know as to what the state allows you to do with an infected hive.

Anyway,I talked with the farmer the beek rents from and walked up and checked out the yard by me.

EVERY hive had blue spray painted dot's!

I haven't treated with terramycin for 2 years,but have tried to follow the New Zealand model for afb control,even though(most)my neighbor's don't,and there are a bunch of beeks too.

And there is quite a bit of afb around here too.

So,I wondered if there are stronger management techniques,other than those hives "mysteriously disappearing" some dark night...I'm KIDDING.

The thing that is most worrisome is that he runs around 1000 hives,and has too much on his plate.

For example,I know a bear tore up that yard this spring,and he didn't get things righted too quick.
Back a couple years ago he lost most of his hives from mites.

My bees would just love to clean up any of those hives this spring.

So I'm wondering,what is the best I can do to protect myself in this situation?

A resistant line sure would be nice...for all of us.

But really,any advice?