Sorry Laurent, I was referring to the draught version. Up until the point where the German and Austrian brewers invaded the country and introduced their practise of serving draught beer by CO2 dispense, the Czechs used casks and air pressure dispense, similiar, IIRC. to the Scots. The beers had the consistency of milk and were very pleasant indeed - these days they are full of CO2 and less pleasant to my palate. You may recall that Bass went around lots of breweries in what was then still Czechoslovakia, buying up redundant casks, when they took over Staropramen, because they bothered to ask their regular drinkers first how they liked their beer served.
As an aside, I had a couple of half litres of draught Budvar in a bar in Sopron, Hungary, on Friday night. I managed to be offered the very last glass from a keg which ran out. It was full of solids and cloudy, so the Hungarians at least are getting the unpasteurised live keg version. I sent it back, and they changed it without complaint, too.