Humpty Dumpty

First time in this forum.

I have a Siamese mix, Thai, that is 10 months old. My vet doesn't like to neuter until 6 months. I had Thai neutered at 5 months because he was humping my 14 yr old cat, Spud. Vet said he was an "early bloomer" and that it make take some time for him to change this behaviour. But it was over as soon as he was neutered. YaY!
But starting this past week-end, he was doing it again with a vengance. Poor Spud.! We told Thai "NO!" everytime and he was good about stopping. But we were home to moniter it. I wonder what Spud has to endure while we have been at work, though Thai hasn't done it since we've been home in the evening.
There has been some "cat noise" outside, being Spring and all.
Would that make Thai 'crazy', or is it just a coincidence?
Why would it make him like that if he has been neutered for 5 months?

Mounting and humping are not exclusively sexually related.
In most cases, it is simply a display of dominance.

In other words, he's taken the top cat spot from the 14 yr old and continuing to let the other cat know he's boss.
As long as it doesn't turn aggressive, it should be ok, most cats will tolerate it well enough.

Yes its a dominate thing....I would seperate them when u can't watch whats going on......because your cat is a senior I'd try to stop that behaviour...

I don't necessarily agree with the others. When I read your post the first thing I thought was I wonder if there are outdoor cats who are triggering his instincts. When I read that there were I thought, Ah ha! and that you're a very astute cat owner!

We've a similar problem around here but it causes my male cat to mark in the house instead of hump the others. In the past, we've had success with Feliway. This year that wasn't enough to cut it and the vet prescribed Megestrol Acetate which has been successful and I like that it's only a temporary prescription.

Anyway, you might try Feliway to see if it takes the edge off things. I suspect it will die down on it's own as spring breeding ceases. Since he was an early bloomer he may just have more intense hormones than other cats.

Let us know what happens. I'm interested!

The adrenals produce male hormones also, at least in humans.