Very weird agression acting out??

Ok all of a sudden for about a week now Tabithat has been hissing and slapping and every now an then attacking the other cats when they get near her. I dont know what could have happend for her to do this. Her Diet is the same, I only changet he cat litter from long lasting oder control to immediate control a sligt diff. in smell but that was 3 wks ago, no new animals have been in the house(they dont mind the occasional lock up for prissy to come in) but even Prissy being in the house never bothered them while they were locked up. I really dont want to get rid of her if she contnues. I cant have her attacking the Kittens and older cats. She is not fixed (she will be here in 2 months along with Jasmin and Trish). She has had heat cycles for about 2-3 months now. Can any one help me. She only acted like this once before and that was when we got her.


Ashley

Sudden, unexplained agressiveness may be an indication that the cat is ill or in pain. The heat cycles are also uncomfortable for her or she may have an infection of the uterus - pyometria. It sounds like she needs to see a vet. Is there any way you can get her spayed earlier? This might help with her aggression.