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View Full Version : Chalk brood: is there a lot of it about this year?



Alvearium
19-05-2010, 09:20 PM
I am seeing a lot of chalk brood about this spring; some quite heavy infections. What are others finding? I had a look back over Eric's articles in the Scottish Beekeeper and how he managed it by sugar feeding. Is this enough or should I use a shook swarm method to try and get rid of it from the apiary? Anyone else have any ideas?
Alvearium

Adam
20-05-2010, 09:32 AM
I have never used solid floors so I get good ventillation and I have light soil and a well-draining site - not damp at all. It is said I believe that chalk brood has been better since the open mesh floor has been adopted. What sort do you use? The usually quoted remedy is to re-queen;

This is from beebase

Cause
Chalkbrood will probably be seen in most colonies at some time but at varying degrees of severity. It is caused by the fungal pathogen Ascosphaera apis.

Symptoms
Spores of the fungus enter the developing larva through the cuticle or orally with contaminated food. These spores germinate and the hyphae of the fungus invade the cells, killing the larva (usually after it has been capped over). Initially the dead larvae will be covered with a white cotton wool-like growth and may swell to fill the cell taking on its shape. After a time these will dry out and shrink to give the characteristic ‘mummies’ that are chalk-like at first turning to a greyish black colour as the fungal fruiting bodies develop. Worker bees uncap the cells of dead larvae so the mummies will be clearly visible; they will also be removed by the workers and may be seen in high numbers on the floorboard or at the entrance to the hive. In very heavily infected colonies, the workers will not be able to uncap all of the affected cells and if a comb is shaken the mummies may be heard rattling in the cells.

Each Chalkbrood mummy produces millions of spores that will adhere to cells and adult bees. It is these spores that are the infective stage of the fungus and may remain viable for up to 15 years. The spores can be spread from hive to hive by drifting bees, or by the beekeeper on equipment and frames moved between colonies.

Treatment
A good, strong healthy colony will usually be able to tolerate chalkbrood and it is not usually a serious disease. However, in smaller colonies or those under stress (for example suffering heavy varroa infestations) chalkbrood can be a problem. The best method for keeping chalkbrood to a minimum is the maintenance good strong stocks of bees, although in particularly bad cases the problem may be solved by re-queening with a young and vigorous queen from a chalkbrood-free colony. Choice of apiary site is also important and you should avoid damp sites.



Adam

beeanne
20-05-2010, 01:21 PM
I have more chalkbrood this year than last - not really infested with it, but definitely more than last year. I only have one year to compare with! They're on the same site and on mesh floor, but the site is near a river therefore likely damper than is ideal. The hive itself is on a very tall stand though. My intention is to keep an eye on things for the moment: I don't really want to move the hive and last year wasn't an issue.