One year old neutered male cat exhibiting disturbing personality traits

[vangogh]

Hi! I have an 11 month old male cat, that seems to be developing a mean streak which I find very disturbing. I've hac him since he was 7 weeks old and he was neutered at around 4 mo. He's an extremely vocal cat, since kitten hood and very demanding. He bays loudly when he's hungry and howls when he wants to play. If I don't start playing with him he'll come over and give me a bite. Not hard enough to draw blood, but tit , does hurt. We have several play sessions throughout the day. His favorite toys, or shgo uI thought, are a laser and a toy similar to Da Bird. He'll leap all over the place going after the feathered bird and chases the laser like crazy. Lately, he will suddenly hiss at the laser light and today he hissed at the feathered bird. He still acts like he wants to play, but this totally pissed off attitude bothers me. He's an only cat and gets all my attention. I've had several cats in the past, male and female, that we're all "only" cats and I never heard any of them hiss. They were all very loving and gentle. They all were front declawed also. I chose not to declaw Vincent, my current kitty, and he's the only one that bites, hisses, and has almost a bully like personality. Should I just chalk this up to "teenage" years? Oh, and the vet says he's healthy.

 

[mani]

Is there something you can think of that has happened at about the time he changed?  It sounds odd that it's relatively sudden.

Is there anything that could cause redirected aggression?  Cats outside etc?

 [article="32390"]Re Directed Aggression In Cats​[/article]  

 [article="29673"]Cat Aggression Toward People​[/article]  

 

[a cattan]

Is it possible that he is in pain or has a Urinary tract infection, cats will go to great lengths not to show pain, he may have crystals or stones, which are painful, these can develop suddenly, please contact your vet, some cats hide when they are hurting, others show aggression

 

[mani]

Is it possible that he is in pain or has a Urinary tract infection, cats will go to great lengths not to show pain, he may have crystals or stones, which are painful, these can develop suddenly, please contact your vet, some cats hide when they are hurting, others show aggression

Yes, quite often that can be the case.  VanGogh did say that the vet had said he's healthy.