Doc the cat might have been an early inspiration for the HB TV cartoon character Top Cat, which premiered two years later. Both felines wore fashionable headgear and lived in an alley, where they often made use of a local phone box.
The orbital sphere Doc the cat is seen in resembles the Soviet satellite Sputnik. The October 1957 launch of the basketball sized artificial object marked the official start of the space race.
The first appearances of Hickory, Dickory, Doc, and Cecil.
Hickory was originally going to be a dim-witted male in blue overalls. It is possible that Walter Lantz Productions opted not to use the dumb-smart formula for Hickory and Dickory, due to similarities with the Looney Tunes characters, Hubie and Bertie.