Unusual marks in hive

[Itchy]

Just checked a few in readiness for oxalic treatment and found one with big streaks across the crownboard, dark brown poo?
I suspect nosema, but would value the opinions of others. Clustered well, few dead bees around.
Treatments for this?

 

[mbc]

Sounds like dysentery to me, could be down to nosema.
Oliver Field, in Honey by the ton, says that shaking them out into a clean box of stores can save them, more likely to kill them off at this time of year IMHO.
It doesnt always spell the end, they quite often shake it off and pick up in the spring.

 

[REDWOOD]

The easiest way of testing is with a microscope
https://secure.fera.defra.gov.uk/beebase/index.cfm?pageid=191

 

[Itchy]

Thanks, I was wondering if there was a supplement I could feed them. difficult to tell how old the marks are. bees seem happy enough. Should I still trickle oxalic?

 

[mbc]

Should I still trickle oxalic?

Personally I wouldnt. If it is nosema, oxalic could prove to be the final nail in the coffin, and with the stretching days isnt it getting a bit late for oxalic anyway ? I havent looked but I imagine most of mine will have a bit of brood by now.
If they do survive but have an unacceptable varroa load that can be dealt with later in the spring anyhow.

 

[Itchy]

They did have maqs late summer

 

[Tom Bick]

If the bees were managing to cover the underside of the crown board at this time of year you would have noticed the top of the frames pretty much stained. If you suspect nosema then best not to use oxalic.

 

[Arfermo]

Sounds like a dose of nosema. Best not to get too worked up about nosema this time of year as there's not much, if anything, one can do about it. Most hives have latent nosema within the bees but if the colony is strong and well fed and without other disease symptoms they usually overcome the ill effects of it by defacating outside when spring arrives, if they don't already dispose of it during cleansing flights on warmish days before then. Oxalic this time of year is too late by far. The very latest for oxalic this year, even with the mild weather that has been around, I would say, is mid Jan.

 

[itma]

Just checked a few in readiness for oxalic treatment and found one with big streaks across the crownboard, dark brown poo?
I suspect nosema, but would value the opinions of others. Clustered well, few dead bees around.
Treatments for this?

1/ it isn't usual to "check a few in readiness for oxalic treatment". It would seem that you have taken off the crownboard for a look?

2/ Dysentery (if that is what it is) can arise from different causes.
There is an association with Nosema apis, but there is a snowball thing, Nosema being spread in the poo. The more poo in the hive, the more that any Nosema will be spread around the colony. But the poo could have started with fermenting stores or late syrup feeding.

3/ Nosema needs a microscope examination of some (dead) bees to confirm.
Most associations have someone happy to help. You just have to get them a sample of bees. BBKA say 30 forager bees. Randy Oliver proposes a method requiring just 10 per hive ("the Quick Squash" method of quantifying Nosema).

4/ Oxalic is supposedly not good with Nosema (but particularly Nosema ceranae - which isn't associated with wall-to-wall poo.)

5/ So best to resolve Nosema status before considering varroa treatment. By the time its known, it is probably too late for Oxalic.

6/ Plan on a shook swarm (or Bailey change), maybe in April, to get them onto clean comb, in a clean (fumigated) box.

7/ A feed of syrup containing emulsified thymol is anecdotally reported as being helpful (lots of threads) - but that is also not for now.


You've got some cold weather coming too - not the time for collecting a sample of bees for testing.
About all you can do right now is to find someone to test them (when you can get the sample).

 

[Itchy]

Thanks all
Hive opened to check for fondant, splats noticed along with 'sickly' appearance. Streaks of 'poo' may be old as colony itself looked good an healthy.
Will not be oxalic treating this one as maqs used in September, but will have a damn good look when weather warms up