Back in the day, Ralston Purina was one of the leading producers of pet food. Not only was there Purina Cat Chow and Dog Chow, but for a while, there was also Purina Puppy Chow.
Today, Purina has long since become part of Nestle, while the Ralston half has apparently retired or faded into total obscurity. Heh, in fact, Nestle is using the Purina name for a former competitor's brand of cat food, Friskies (originally made by Carnation, which was also acquired by Nestle).
I digress. We're scoping a 1977 animated spot for Puppy Chow, narrated by the original voice of Winnie the Pooh, Sterling Holloway, who also croons the jingle du jour:
This is where simplified animation works best.