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gavin
16-10-2010, 11:36 PM
Thanks to PLB on Bee-L for posting this one, but I thought that Scottish beekeepers might like to try this. What is wrong with this colony?

http://www.gigapan.org/gigapans/27538

G.

gavin
17-10-2010, 09:47 AM
I see that Chris Slade has given the answer on Bee-L, so no peeking! I saw signs of two pathogens, one serious and one common and usually not serious. Maybe a third pathogen too. There are several different things there that point to the worst pathogen.

G.

Trog
17-10-2010, 10:31 AM
Hi, Gavin. I couldn't get the link to work.

lindsay s
17-10-2010, 02:17 PM
I’ve just checked a booklet I was recently given and one of the main symptoms seems to be American Foul Brood. The booklet is called Foul Brood Disease of Honey Bees and it is available from the FERA National Bee Unit. I would recommend this booklet to all beekeepers. By the way Gavin can we have an update on this years AFB EFB outbreak in central Scotland.

Jon
17-10-2010, 07:00 PM
OK
First up to make a fool of myself. I haven't looked at Bee-L yet but will in 5 minutes.

There is not much that frame does not have.

There are EFB larvae as judged by the abnormal position in the cell and some of them are discoloured as well.
There seems to be AFB present as well as there are sunken and perforated cappings as well as the odd cell of brown gunge.
On the left of the frame there are cells with what looks like white scale. I don't know if this is an artifact of EFB but if not it may be something like sacbrood or stonebrood.

Ok off to look at Bee-L now!

PS.
I am sure there is varroa present as well.

gavin
17-10-2010, 10:56 PM
Hi Lindsay, Jon, anyone else looking in ... and Trog, try again!

There are a lot of cells with funny white patterns in the base. I think these are just reflections on glistening honey - nothing to worry about.

I can see signs of three pathogens. The most serious is EFB, so well done Jon.

There is one square of 5x5 cells to the right and a little below the centre with five full-sized larvae with all the signs of EFB. Larvae twisted out of position, discoloured and some melted-down. There are also lots of dead (brown) young larvae across the frame. So many of them in fact that I think that this colony is approaching the 50% open larvae affected level at which treatment becomes untenable. The early death of small larvae is probably the main reason for the spotty brood pattern, a danger sign in any colony and something which always needs further consideration. Larvae dying before the cell is sealed dry down and the bees can remove the resulting scales often intact and before they have voided any gut contents, where the bugs are to be found.

The cappings are variable. Some are darker and some paler. I don't think that means much as the brood pattern is all over the place and there will be older dark ones ready to hatch. I have seen old really dark and sunken cappings in colonies with heavy Varroa infestation but no foulbrood. Often there is something amiss in such cells, but not always. Some of the cappings are uneven, as if the larva underneath was in some distress. In them (always worth knocking the tops off these) you might find chalkbrood, sacbrood or an EFB-infected larvae that just staggered on to the capped stage. You might also find AFB. As there is EFB in this colony at quite a high level, I wouldn't suspect AFB but it could be there. AFB will kill young larvae just as EFB does, but most survive then die around the pupation stage after capping. The ropey test with a match or twig is diagnostic.

There is a hole in some cappings. Most are single central holes, which could be cappings not yet complete, or bees opening up dodgy cells. AFB perforations are more erratic. You can sometimes see fat juicy Michelin men/larvae inside those slightly open cells, and these are healthy ones being sealed. Some seem to have chalkbrood and were probably opened.

I can see three or four larvae infected with sacbrood. Brown fingers pointing out the way straight at you. There are also some dried down scales which look loose rather than firmly glued to the base of the cell, so these could be either sacbrood or EFB but not AFB.

Varroa? Well without bees all you can do is look for the white spotting of Varroa faeces in newly vacated cells. The newly vacated cells have rough rims and are often more circular, and there are very few of them on this frame. Newly vacated cells haven't yet been fully cleaned so this is where to look for Varroa faeces. The faeces will be right at the back in the upper corner, and I don't see any cells with this so I don't think that there is a particular Varroa problem in this colony. Can't be sure though.

Add a few chalkbrood here and there, and that is what I see. Time to call the inspectors. Shook swarm if you like and if the season is right and the inspectors agree, but this colony is already heavily infected.

best wishes

Gavin

Phil McAnespie
17-10-2010, 11:32 PM
Hi Gavin,
How do you manage to get time for all this good work.
The attached site is great. I was really impressed with the images and detail.
To answer your question, there are signs of EFB, Sacbrood, Chalkbrood and I would like it tested for AFB.
I see some eggs on the side of the cells rather than the bottom and it really is time for the old comb to see the fire!!
Hope you are doing well.
Phil

gavin
17-10-2010, 11:45 PM
Thanks Phil

Yes, you are spot on with the diagnosis. I think that the photos and the site were set up by Dennis van Engelsdorp of Penn State University.

G.

Neils
18-10-2010, 01:18 PM
Know it's easy to say when the answers already up here (and SacBrood is disclosed in the photos) but I agree with Phil. is an easier question what isn't wrong with this frame? The obvious first point that something isn't right is the overall condition and pattern of the brood, centre right of the brood pattern there are several miscoloured and mis-shapen Larvae that make me think EFB immediately. Some of the perforated cappings worry me too.

Every egg I can see is on the sidewall of the cell, I'm not too sure what to make of that, if there were more than one per cell I'd be thinking Drone Laying workers, damaged queen perhaps? Aren't eggs on the sidewall indicators that, perhaps through careless clipping, that her back leg(s) might be damaged?