All our bees are checked before, or as, they go out to cucurbit pollination.
Any hive that do not make our minimum standards are held back. One such
disqualifier is American Foulbrood, and we do have an occasional case.
 
(Any commercial beekeeper who will not admit that he has some AFB has got to
be a liar!   We have one "hot spot" where a lot of equipment has been
abandoned several years ago by a beekeeper who was put out of business by
unchecked AFB.  In that area, which unfortunately is a major veggie growing
area, we must be extremely diligent in medication, and we usually still pick
up a few cases.  I have not been able to locate all the exact spots, but
there are many.  I don't hold it against a beekeeper for getting foulbrood,
but for letting it run, unchecked, though his outfit.)
 
I've done a number of experiments with foulbrood. In the past I've taken the
cases to a "hospital" yard and treated them with TM for the rest of the
season.  Where there is only a few cells infected, I've gotten good results.
 Where there are massive infections with scale in many cells, it's not worth
trying to save the comb. They usually break down again.
 
In the spring of 96, I had one such case that I treated differently. They
were badly broken down, but the hive population was still pretty good. They
were the lone hive left in the bee yard, so they gained a few extra bees from
the drifters that were out in the field when we moved out the yard to
pollination. I treated them with TM, not to clean up the infection, which I
considered impossible, but to keep them alive and not get robbed out before I
could get back to them.
 
I returned to the yard at the end of pollination season (late June), and
shook all the bees off the frames. In place of the original hive, I put a new
one with all foundation. The bees crawled into the new hive.  The old hive I
took home to burn the frames and sanitize the box.
 
I fed the hive heavily, as the spring honeyflow was over.  In this area, the
spring flow is usually "it."  Bees can starve at midsummer, expecially if the
thermometer is in the 100 degree area. I also kept TM on them.
 
On syrup, they drew out the foundation beautifully. By fall they were ripping
strong, and there was no trace of AFB.
 
I put a deep of foundation on them in early fall, over an excluder, because
they needed space. They drew this as well, and filled most of it. I left this
on them until early March.  They still showed no trace of AFB.
 
I then felt safe to use these frames for feed frames for other weaker hives
(along with TM, of course). So I removed the deep for feed honey, and put
more syrup to these bees.
 
By mid-March they were so heavy, I removed the feeder and added supers, which
they promptly filled with bees, and by the first week of April they were also
full of honey.
 
In the fall I had brought back 40 hives to the yard.  All had been fed,
treated with TM and Apistan over  the winter, and most looked quite good.  I
used this yard exclusively for spring honey production.  No nucs were made,
only a bit of brood equalizing.  At the end of the first week of April the
experimental hive had three shallows full of capped honey. The other hives
had some honey, but little capped.  I removed the three supers for
extraction, and gave them three more.
 
In late April they had these full again, and were about equivalent to the
rest of the yard at that point. So they doubled the average production for
the yard.
 
Two conculsions from this (admitedly limited) experiment:
 
1.  Placing AFB bees onto foundation seems to clear up the disease.
 
2.  The Europeans are probably right about renewing old, dark combs
periodically. Much of my operation has, at least some dark old comb in the
brood chamber, and it probably does carry pathogens. This hive with only
newly drawn comb was amazingly powerful. The bees looked large (well fed) and
clean.  The hive smelled sweet and good. The brood pattern was excellent.
 
They were the kind of hive I might mark as possible breeding stock, if I
hadn't known their unique history.
 
Just food for thought.
 
I'm going to do more of this.  -Probably even with some bees that are not
infected.  If they will draw such nice comb at midsummer on syrup, it would
obviously be a way to get some "premium" bees ready for next spring. Maybe we
can kick up our honey production.
 
This may be the main reason why hobby beekeepers often outpace commercial
beekeepers in production per hive. Some get all excited and increase the
number of hives, only to find that it is much harder to get the same
production per unit from 100 hives as one got from 5.
 
Forgive my ramblings and natterings.  Maybe it will trigger some creative
thoughts?
 
[log in to unmask]    Dave Green  Hemingway, SC  USA
http://users.aol.com/pollinator/polpage1.html