puppies testicles dropping

Question
how old should my pup be when he testicles he is 8 weeks old i can see any testicles and when i took him for his first injection last week the vet informed me she could only feel one tesicle is this normal?

Answer
Puppies testicles descend at different ages and sometimes one will descend before the other one does. There are times where they will come down and then go back up. It's a way to regulate the temperature of the testes'. An approximate age for both testicles to be descended is about 3 months. Most dogs (depending on breed) will display both at this age. There are times, however, it may take a little longer, but any time past 4-5 months needs to be checked by a vet.