5 so far (2 wolf, 3 dog).
The wolf scenes are variations of each other one with a single wolf and another with 3 wolves and you get both through The Rangers questline. The Rangers will also have you exploring boars, lions, and mythical creatures.
The dog walker job will get you 1 dog scene if you choose "long walk". And you can get another scene by going back and talking to the dog owner after enough long walks and a high depravity level, although this 2nd scene is not repeatable and won't show up in the gallery either for some reason.
And then you recruit Beth and her Dog for the Breeding Ranch, but so far there's only 1 CG in game where you spy on them and then recruit her.