Ask a Vet | Aggressive Cat Behavior

By Online Vet, Dr. Laci

It is a problem that I had heard clients complain about before but had never had the stress of dealing with myself. Cats A and B are best friends and do everything together. Cat A goes to the vet and Cat B stays home. Cat A returns to receive anything but a warm welcome from Cat B, who hisses, attacks and seems determined to destroy Cat A. Cat B is convinced Cat A is an enemy and a threat. A previously wonderful cat relationship seems destroyed, and the household is a tense environment for all humans and furkids involved. “Will this ever improve…” you may ask a vet? Read about my own experiences.

ask a vet, online vetWe travel with our pets, like many people across the world do nowadays. Usually this works out okay, but our calico cat Mackenzie did become ill on a recent trip and we soon found ourselves in the vet emergency room at 1am. While Mackenzie suffered no long-term ill effects from the cup of espresso she managed to lap up while I was in the other room, the vacation condo was anything but relaxing when I returned home the next morning with Mackenzie in her carrier.

Rigby, our Siamese did not greet us with a welcome, to say the least. There was hissing, fur flying, growling, screaming, and full on attacks. Initially, I (and Mackenzie) was frozen and shocked, and then as soon as I could compose myself, I realized that Rigby was experiencing what is called non-recognition feline aggression. She didn’t know that Mackenzie was her beloved sister, as Mackenzie smelled like a stinky vet hospital and it is believed that cats recognize each other off their scents, not visual clues.

Non-recognition aggression in cats is an bizarre phenomenon that does not seem to occur in dogs—thank goodness. What it is about these mysterious felines’ personalities or sensory perception that leads to these events remains largely hypothetical, but it does happen and the bad news is there is no easy fix.

What finally worked for us was bathing both the cats in addition to feeding them in the same room. The bath really seemed to help speed things up in our household, but that isn’t always the case.

If you find yourself in this situation, you must separate the cats for as long it takes for the aggresion to end. This may be a few hours or you may be unlikely like we were and it make take upwards of two weeks. You can try to counter condition the aggresor cat by offering food only when the other cat is in sight; even if they are on opposite sides of the room. Make sure the aggressor is on a harness for the safety of all involved. You gradually decrease the space between the cats. Whenever one shows any aggression, distact him/her by making a loud noise, for instance.

The chances that the cats’ relationship or at least tolerance of each other can be reinstated are good, but I learned that future meltdowns are likely once this sensitivity has been recognized. In other words, history is likely to repeat itself if steps are not taken to prevent recurrence.

Useful measures to take are:cats aggressive after vet visit, ask a vet

Make sure that a cat returning from the vet’s office is fully recovered from sedation or anesthesia before reintroduced into the home

Bathe the returning cat to remove veterinary-type odors before returning him to the household.

After bathing, rub something with the cat’s regular scent back on them, such as a blanket or toy they often sleep with.

Keep cats separate for awhile after one returns from the vet’s office until they re-familiarize with each other’s sounds and odors.

Consider using pheromone therapy like that of Feliway – here are the sprays and plugins on Amazon: - - Make a name for yourself in the digital world.

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As for me, I think both girls will be traveling to the vet together in the future. That was not something I want to go through again anytime soon, and I’m sure the my two cats would agree.

Dr. Laci

Online vet Dr. Laci reviews various medical and behavior problems here on her blog. If you need to ask a vet a question tailored to your pet’s medical question, ask a vet a question in the box on this page to get online vet help.


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One Comment

January 10, 2013 at 15:45

Monhagen Vet is your Middletown Veterinary clinic treating your favorite furry pet, birds, and reptiles. Bring your best friend to Middletowns favorite vet, Dr. Furman.