Thank you for the interesting question.
I am not sure which scriptures to which you are referring as there are multiple teachings on unclean animals. There are those that are forbidden to eat enumerated in Leviticus Chapter 11. Again, these are laws pertaining to eating and not touching. There are animals that if touched, will render the person ritually unclean until sunset. Some of these laws are as follows: Lev. 11:29;39 to name just two. Dogs are not unclean. As a matter of fact, the essence of the word dog in Hebrew (Kalev) is “close to the heart of the master.” May HaShem bless you for your service and your service companion.
I hope this answers your question.