I would put the kitty food up where the puppy can't get it. My dog, Jesse, still tries to chase the cats. One, Peek-a-Boo, has figured out that if you don't run, she can't chase her!
The other kitty, Autumn, freaks out and runs away. Then Jesse chases her. They are slowly becoming friends though. Don't worry, I am sure that they will become pals in no time!

Steph and Jes