Sorry he was killed off, some of the most humorous moments of the last several books centered on this canine.  Both Kane and Grant were left scratching their heads trying to figure out why Dog was so special.  I was initially thinking he was some kind of reincarnation of the mythical Cerebus who decided to attach himself to Lakesh's Rebel group.  We now know that he was "possessed" by Igigi souls looking for a new host body and apparently accounts for his prenatural intelligence and fighting abilities. I think Rosalia was decieving herself when she told Kane she kept herself "distanced" from Dog by not giving him a specific name and becoming too attached to her pet.