Dogs cannot asexually reproduce, and the species that can, like doberkim said, just... can. I don't see how one can have an opinion for or against it - it's nature. I do agree with Mona that it can result in a decrease in diversity, which can lead to all sorts of odd things.. Whether or not that's a bad thing, I really don't know. Perhaps it's just evolution at work?
Or, maybe I totally misunderstood. Are you talking about cloning, or AI?