Huck's reaction to my bringing his cat carrier up from the basement was an immediate "No." He took one look and lit out for the far corner of the living room, where he has a refuge: a Huck-sized gap on the lowest level of a shelving unit, somewhat blocked by a couple of boxes and his climbing "tree."
I managed to haul him out by main force,* which left me with a generous armful of struggling tomcat to carry the length of the house and somehow get into the carrier.
There's a trick to it. You can't get an unwilling cat into a carrier head-first, and backwards is even more a battle. But you can stand the carrier on end and lower the cat in, tail-first, then shut the door and gently turn the carrier horizontal.
He didn't approve of this, but I got him to the vet. She'd been talking about taking a biopsy of the bald, scabby spot between his shoulderblades. After looking him over, she decided he'd healed up a lot since his previous visit and she wanted to try a different topical medicine instead. Huck and I both thought this was a fine idea. So now instead of ointment, he gets a little spritz of stuff on the spot, mornings and evenings.
He's not so sure that it's a good idea, but he'll tolerate it.
* Each cat has an actual refuge, a place from which I will not haul them out, though luring out with treats is okay. Huck's is his "cave," a carpet-covered tube low on his climbing tree. Rannie's is her "egg," an oval, covered cat bed that is just her size that replaced one of the end cushions on the window seat. But Huck will head for his spot on the shelf if he's worried enough, since it takes more work for me to get to. I think he feels it's a better defensive position.
BUILDING A 1:1 BALUN
6 months ago