Just this very afternoon.
The missus and I have two cats, each of us bringing a fuzzbutt into the relationship. Mine is the Big Black Fluffy Thing, while hers is Basement Cat. (The resemblance is uncanny, and I've been collecting cheezburger photos to make an album for her.)

I went out today and got flea treatment for them (the stuff you squirt on their skin, which they both hate) and de-worming medicine as Basement Cat has been chewing her ringpiece lately. I also bought a small syringe to inject the de-worming stuff into her mouth.

I've been outside working on a stained glass project, and was showing it to the missus. She noticed the Big Black Fluffy Thing laying nearby in the sun. I commented that she was going to be mad at me soon when I gave her flea treatment.

"Yeah, but she's really gonna be mad at getting something jammed in her butt," she replied.

"What?"

"You know, the de-worming stuff."

I put down the piece of glass I was holding. "What! No, you don't put it there, you inject in in their mouth so it goes through their intestines and kills the worms!"

She turned red and started giggling.

Horrified I stared at her. "You didn't already do that to your cat, did you?!?"

It took her a minute to communicate that no, she hadn't anally violated her cat, that if she had I would have heard the screaming.

It probably would have been one of the rudest things I had ever witnessed, and certainly would have been a memorable moment for the cat.
( The Resident Loon Not a demographic. Do not measure., Wed 17 Aug 2011, 22:08, 2 replies)

Oh god. Having de-everythinged teh animals last week I'm now kakking meself
at the thought of Jonesy (the fat, white bastard cat) taking some worming paste up the date.
Mind you all we'd have to do is put some on some catshit to get the dog to eat it... wait, self-defeating cycle.
(Misery McUglywife an attention seeking sociopathic fuckstain., Thu 18 Aug 2011, 9:06, closed)

Then you should appreciate this:
catenema.com/catenema.com/cat.html

(Worksafe, and will cause the giggles.)
( The Resident Loon Not a demographic. Do not measure., Thu 18 Aug 2011, 16:19, closed)