My Scotties are fascinated by the snakes, they sit there hypnotized at night when the snakes come out (which is why the snake cages are way up high until the rack comes), so I just don't take the snakes out unless the pups are in their kennels. But Scots are not particularly smart/have an incredibly strong prey drive. I know loonunit has a lab and who gets along nicely with her (totally awesome plethora of) snakes. From the dog point of view it seems pretty specific to the individual dog. From the snake side, none of them seem to notice or care that dogs exist.