When writing a joke where the punchline will be a cat food named "Kitty Farts A Lot", the set-up should avoid gratuitous references to shit.
It's like eating a huge steak dinner and having yams for dessert. It's incongruous. You need to follow up steak with creme brule, bitches.
And you should probably rethink the whole stupid joke if your punchline is analogous to yams.
Though I'm almost 100% positive "Kitty Farts A Lot" is gold with the Jean Teasdale set.