If I had too, I would say that three of my dogs are right~handed and one is left~handed. How much of this is
acquired (I am right~handed) and how much is
natural I could not say. The only way that I could hazard a guess would be to say that when I cast them off for a retrieve or to hunt, three will always veer slightly to the right and one to the left, and then they correct their position to work into the wind.
Incidentally, they will use
either front paw when pointing game birds, but always their back right paw for wabbit or hare 
Leigh