>  One would have to study
> clean new hives, versus old sticky ones, to determine whether a clean
> environment is really better or not.
>

Has been done

Marla Spivak presented in Nordic Baltic Beekeeping conference in Denmark a 
study made by Mike Simone in Beltville lab about propolis and bee health.

Young bees were put in new boxes. 4 frame boxes were divided to 3 groups. 
One was sprayed inside with ethanol/ Minnesota propolis extract, one with 
Brazialin propolis extract and control was sprayed with only ethanol.

Bacterial load in bees was measured by pcr. Bees in propolis treated hives 
had about half of bacterial load compared to control. Immune responses were 
much less elevated in bees from propolis treated hives. There was difference 
between the two propolis types, but not much. Conclusion: nest environment 
can influence immune expression in honey bees.

I believe in the study but still rotate combs a lot. I believe that dark 
combs have too much pathogens. Loosing some propolis is less negative 
compared to pathogens removed with frames.

Ari Seppälä

Finland

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