how to determine foal stats?

are the stats that foals are born with calculated from the day their parents were bred or the day they are actually born?

I've only ever had foals born after using a breeding speed potion :P

I believe it is the day they are bred. I had a pair that was dressage discipline and I bred them before I remembered to change them over to show jumping, which I did right after I bred them, thinking the foal would get the stats the day it was born. The foals stats were all concentrated still in the dressage area (agi + int) instead of the show jumping (agi + spd), so I'm assuming it's day of breeing, not day of birth.