A redditor today posted this and some suggestions have come in, but I’d rather just post the comic and see what you folks think. What is the joke? What is Jim Davis suggesting happened?
Eeeeeeeeeeeeewwwwwww!!! They’re obviously at the vet’s, and he just chugged a sample of … dog urine (or maybe semen)??? :eek: 
:dubious:
Liz is either messing with Jon or Jon drank some doggie fertility drug.
I was thinking the first one.
Only dog jizz makes sense.
Do they actually have such things? I thought there were too many unwanted puppies and kittens in the world as it is! :eek:
I imagine only professional breeders would be interested in such things.
Can you tell if a dog is pregnant from her urine? 
Not really. Messing with his head makes the most sense. Why would anything beneficial to the birth of healthy puppies be on the same table as a cat?
Because comics don’t need to make logical sense. (One might better ask why Jon keeps Garfield around, or why Liz dates Jon.)
Dog semen seems to be intended. (Even if one concedes that Liz is messing with him, that would be what she wanted Jon to think it was.)
If Garfield had more jokes as revolting as that one, I’d like it a lot better.
That one’s a little…odd…for a mainstream strip.
About as odd as this one, though Larson claimed that the obvious interpretation was completely unintended (the dog was just supposed to be howling in triumph):
This very strip was the subject of the thread that made me decide to join the SDMB eight years ago. I laughed so loud that I scared my own dogs. (RIP, Jenny and Lacey.)
liz is playing a joke on jon. No vet would keep anything of importance in a coffee cup. Come to think of it, no one in any profession would.
But I must say this is a huge improvement over 8 identical panels of garfield doing nothing and then a joke about how lazy he is in the last panel.
But still not quite as good as Garfield minus Garfield, which isn’t a comic strip about a pasta eating cat and is about a lonely young man slowly going insane.
I wish I’d see that thread at the time. So many puns come to mind.
what about a barista?
It’s not clearly a coffee cup. No handle can be seen in the last panel.
Surely Jim Davis was also cleverly calling attention to the unfortunate state of present-day knowledge of biology, with this depiction of a man who believes that conception occurs in the stomach. In the stomach of males.
Sad, really. Davis performed a great service in highlighting it.
Well, given their relative positions in the strip, I was thinking of the old joke that ends “Aw, turn her over, dad! I want puppies!”