My voice also gets high pitched when I talk to my doggies! Ha Ha. I definitely talk "baby talk" to not only my sweet little doggies but to other animals as well. I will talk that way to a certain extent to a stranger's pet or my friend's and neighbor's pets, however I don't do the full blown "baby talk" that I do with my own. They would think that I was crazy!
I find myself talking "baby talk" to animals more than I do actual babies! Ha Ha. If I see someone when I am out and about and they have a dog with them, I am definitely quicker to go up to them and want to talk to it, pet it or even hold it vs. if I see someone with a baby.