I am still curious regarding the cartoon.

It was black and white, had the horse race with the Beetle Bomb commentary and fairly rudimentary animation. I checked the Silly Symphonies that were listed on the Net, but its not there.

There was a site which mentioned that Spike Jones had been involved with a cartoon company called Cinamatone in the 1930's, but I could find no further information regarding the company or any animations listed for it.

This is definitely a job for supersleuth.....Sorcha.