Chalk brood

[Do224]

I’ve four colonies. Two are doing great and were given an extra brood box about 10 days ago. The other two are struggling and each only working about 7 frames. They’ve both got a few old black frames which probably should have been replaced. They both have a lot of chalk brood which I feel like is their main issue. Should I;

(a) give them a chance and wait and see
(b) combine them
(c) requeen them when I get cells I can use from one of my good hives.
(d) something else!

 

[Erichalfbee]

If they were mine I would combine them, wait to see how the colony goes and be prepared to requeen with a mated queen

 

[ericbeaumont]

give them a chance and wait and see

Chalk due to winter damp disappears in better weather, so yours is likely to be genetic, for which the answer is to re-queen from a different strain.

The non-chalk colonies may be carrriers, but strong enough to shrug it off. At some point, replace infected kit and clean it in the usual way: scrape, scrub with washing soda/ bleach, or scorch.

 

[Michael Palmer]

I would requeen them with hygienic stock. I'm not sure if anything like that is available to you.
Are there any UK queen breeders who are using the frozen brood assay for identifying hygienic stock? Believe it when I say,
at one time my operation was stinky, rotten with chalkbrood. 800-1000 colonies. I requeened all chalky colonies with the tested queens.
Chalkbrood disappeared in a month, as soon as the new queens bees emerged. To this day, 20+ years later I see, practically, zero chalk in my operation. Today, my breeders are all tested with the Frozen Brood and UBO assays.

 

[hemo]

C.
B. If they look weak.

In the past even with just mild CB , I have requeened /changed the Q line of that particular colony.

 

[Do224]

I think I’ll wait until the start of May and then pinch a frame of eggs from my best colony and give it to the chalk brood colony to make a new queen with (after squishing their existing queen)

 

[Hebeegeebee]

From my experience, chalk brood follows the queen - I've tried it by putting one in a chalkbrood-free hive.
And if a chalk-brood frame goes into a good hive, the chalkbrood goes and it does not contaminate the remainder of the good hive. It might not always be the case and I would not reccomend it as a strategy, however from the limited tests I have done, it's more of a genetic issue (like occasional bald brood, say) rather than anything else.