Will Falconer, DVM Moderator
I'd start with repeating his titer. A colleague of mine stopped all rabies vaccines in her horse and watching his rabies titer climb for the next 8-10 years!
Also, a very important understanding that I suspect Jean Dodds is not on board with, but Ron Schultz speaks to: ANY titer shows there's protection. The adequate vs no argument is a red herring. Titers only measure antibody production, which is only part of the immune response. Any evidence of a titer, AFAIK, indicates immunity has set in, and he should be protected going forward. Six months is plenty old enough for the average healthy animal to mount a significant immunity, too, so I'm glad he was this old when he got his rabies vaccine.