My father was bitten my dog last dec 2013 and got anti rabies vaccine. Now he was bitten again yesterday july18, 2014. does he need to get a vaccine again? Even my dog has anti-rabies last jan 2014.

Unclear. It's a bit unclear to me about the need for rabies vaccination. If your father was bitten by your dog - and it has been kept up to date with the standard rabies series - it's not clear why he initially needed rabies vaccination. The same would be true now, if your dog remains up to date. Even if your father is vaccinated and is bit by an unknown dog, two more doses of vaccine would be standard.