I have a Dogue de Bordeaux bitch that is a super keen hunter. She's not big for her breed (42kg) & is very agile, & super keen to please & retrieve. She has retrieved ducks without any training but is a bit stubborn. I also have a male Bullmastiff (67kg) who isn't so keen (he doesn't like getting wet!) but I bred them & 2 of the last pups are now very good hunting dogs & 1 is on a dairy farm getting in the cows. Anybody else use them?