[Edi]

Actually, as long as you are hunting in provinces with a lab and no sacrificing priest, you can use the 'Z' shortcut to pool slaves into the lab from all commanders in that province. So if you only have a few provinces where all of your hunting is going on, it's almost as good as universal pooling and even better in some respects because you don't need to separately micromanage your combat blood mages and sacrificers again.

Edi