My Lab will NOT drink out of the toilet . . . she prefers the water dish we leave in the shower stall.
However, the three Siamese cats DO drink out of the john. It's pretty disconcerting to come waltzing into the bathroom and see a skinny little Siamese tail straight up in the air and two little hind feet gripping the seat for all they're worth . . . wish I had a pic but they always take off running when I come in . . .