I lost a hive and am wondering what caused it

[bpmurray]

I lost a hive a few weeks ago. Up to then, they seemed OK with occasional flying bees, weather permitting. When I noticed it was really quiet, I opened the hive to see them all dead. There were signs of dysentery on the frames so I was worried about nosema - yes, I know, dysentery's not a symptom of nosema, but it often occurs with it. So I squished the bees and looked at the bee soup under the microscope, but no sign of rice-shaped bacteria. A friend suggested examining the poop and I did that with exactly the same results. Anyway, what I see are pollen grains and lots of small round shapes. I'm hoping that someone much more experienced than I am will be able to identify what's on the slide. Both pics are at 400x through oil.

Pic 1 is focused on the pollen, and the round things are almost luminous, presumably because of distortion and the fact that they're out of focus. Pic 2 is focused on the round things, although there's no discernible structure.

 

[oxnatbees]

There's a thing called Amoeba Disease which has symptoms similar to nosema, but the amoeba are larger than nosema's rice shaped bodies. It's rare, but becoming more common. Check that out on e.g. the national bee unit's website and other good info sources.

 

[bpmurray]

There's a thing called Amoeba Disease which has symptoms similar to nosema, but the amoeba are larger than nosema's rice shaped bodies. It's rare, but becoming more common. Check that out on e.g. the national bee unit's website and other good info sources.

I suppose those round things could potentially be amoeba cysts.

 

[ericbeaumont]

could potentially be amoeba cysts.

Sugar crystals, perhaps.