The Beverly Hillbillies 2x23

Ellie has Dr. Martin of the zoo come over to treat her dog Duke who is sick. But Granny mistakes a bug repellent salesman Jim Gardner, who ends up falling for Ellie, for the veterinarian. Granny thinks he is no "Critter Doctor" but actually a "Bug Doctor" who is there to sell "bug vittles". Granny is taken with Dr. Martin, after finally meeting him.