You can pick up the dirt by running a flea comb against the direction of your dog's fur growth. You can often see it in hard-to-reach places like the base of the tail, middle of the back ...

To check your cat for fleas or flea dirt, run a flea comb through your cat's coat or part the hair with your fingers to examine the skin. If you find live or dead fleas or flea dirt, your cat has ...