All I did was replace the various wolf breathing sound effects with a silent 1 second wav file. No esp, and the main version will silence breathing for all wolves at all times.

The No Run version only silences the breathe sound effect if the wolf isn't running.

The Run Only version only silences the breathe sound effect while a wolf is running.

If you would rather a version which only silences wolf breathing while a wolf is your follower check out Volek's awesome Silent Wolf Followers.