How many pints?

Just wondering how much Vitae can be extracted from your average Cainite? Just out of scientific curiosity, of course, for an associate of mine. I'm not saying I know someone who might know someone who has a half dozen "specimens" staked and chained up somewhere... Also definitely not implying they'd be interested in how to extract and store any of it for later consumption and/or sale.

-"An Ambitious Revenant"