my cat is mounting and humping things!

Question
I have a 3 1/2 year old neutered male cat. He was neutered when he was young, he is the only cat in the household and has never exhibited this behavior before. About a week ago, he started to paw at things with both front paws, then he would "mount" the object and start "humping" it. He purrs as he does this and I turned him over the first time he did it & saw that he actually had an erection! He first started doing it to my fleece jacket, then pillows, and now seems fond of a stuffed animal gorilla! If he had only done it once, I wouldn't have worried, but he did it 6 times in the span of a couple hours on Friday. He has done it at least a couple of times each day since (and that's just what I've seen when I get back from work!). I have heard that when neutered cats mount, it is often a display of dominance, but there are no other animals in the house. I've also heard that "humping" things may be a sign of a urinary tract infection, but I don't know what the other symptoms would be and he doesn't seem ill or in pain. Any other ideas? Is this normal behavior? Is it normal for it to start after age 3? And, he's not just mounting, but actually simulating sex! Is that normal for a neutered cat? Is it just a phase he'll 'grow out of'? Please let me know what you think... Thanks!

Answer
other signs of urinary tract infection: trying to pee in other places other then the litter box.

i have never heard of the mounting, humping actions as a sign of urinary tract infection.

now.....to answer your questions....yes this is normal. all altered cats still enjoy sex.  altered females will still allow a male cat to mount them and even penetrate them.will he grow out of it? maybe not, that really depends on the cat.is it normal to start after age 3? sure! maybe he is just now sexually mature! is it a sign of dominance? YES!!! and it has nothing to do with other animals at all. he is feeling his manhood!

there really isnt anything you can do to make him stop, other then hide everything he humps, but if he is only aggressive towards the objects, there isnt any harm in what he is doing. its embarassing when you have guests, but, yes its totally normal!