My #Cat Had Non-Recognition Aggression #cats #pets

My beautiful mom with 3 of
our pets, circa 1970

I've had pets my entire life, as far back into my childhood as I can remember. Usually at least three in the house, but never less than one.  I thought I knew quite a bit about pet behavior after all these years, and I did know enough to guess one of our cats, Max, had a possible bladder infection two weeks ago, and that something like that was serious enough to warrant an immediate trip to the Emergency Vet (of course, it happened on a Sunday).  I recognized some of the same symptoms displayed by a cat we had when I was a teen, and remembered male cats are more susceptible to bladder issues.  I was in the right ballpark, but it was much more serious than an infection--Max had a complete blockage of the urinary tract.  A life-threatening condition.  He was whisked into the back room, shaved and sedated, and then catheterized.  

This was, of course, terribly upsetting for the humans who love him.  And then I also worried about the effects of his absence on his biological brother, Jinx. These two kitties were born in a shelter together, fostered together until the reached the required age for adoption, and then adopted together by our family.  They had never even spent a night apart.  And Max required hospitalization for three days.

Jinx and Max on their favorite perch

I couldn't wait to reunite the brothers once I excitedly hauled the cat carrier back into our house.  I gently pulled Max out and set him on his favorite perch on the cat tree.  Jinx came padding down the stairs to greet me, and I scooped him up and set him beside Max, exclaiming, "Look who's back!  You're brother's home!"  

Jinx took one sniff of Max, then let out a nasty hiss as his fur lifted from his back.  With a low growl, he leapt away, tail swishing.  For the rest of the day, he stalked poor, tired Max wherever he went, swatting at him when Max was in range.  I was beside myself.  I've had cats all my life, and I've never, ever seen anything like this.  I even checked Max over to make sure I had brought the correct cat home from the Emergency Vet.

Once I had verified Max's identity, I called up Google, trying to figure out exactly what to type in.  Finally, I think I wrote something like "My cat came home from vet and other cat" at which point "hissing" filled in as a suggestion. Good enough.  I clicked and quickly discovered that this had happened to other people who had cats who were best buds before one headed off to the vet.  In fact, it had a name: Feline Non-Recognition Aggression.

On the one hand, I was relieved this was an actual thing, and not terribly uncommon either.  On the other hand, I was devastated.  My cats were so close, inseperable brothers, and now Jinx LITERALLY did not recognize his litter mate.  Max smelled different, like the other animals in the hospital and the IV meds that had been pumped into him for days.  His legs were shaved to allow access to his skin and veins.  And he'd been absent for three days.  Jinx behaved like I'd brought some unknown enemy cat into his house, and he was not happy.  And poor Max had no idea why Jinx was behaving that way. Could a serious illness and three days at the vet erase the two years they'd spent together, since birth?

Max's new haircut

There are a number of posts and articles that discuss how to handle Feline Non-Recognition Aggression, so if you're experiencing it yourself, there are suggestions out there.  Basically, you have to take things slow, and go through the motions of re-introduction as though the two have never met before.  I wish I'd known about the possibility of this occurring before I tossed them together, but at least I was able to find help quickly and start trying to fix things.  And thankfully, with all the pets we've had over the years, I've had lots of experience successfully introducing animals to each other.  The one thing I didn't know about was a type of diffuser that emits an odorless (to us) substance that calms cats.  I purchased one quickly here and plugged it in where they spend the majority of their time.  I kept everyone apart at night until things got better.  And, things DID get better, much to my relief.  So take heart if you've found this blog because you are experiencing something similar.  Max began to smell like himself again, Jinx figured out who he was, and their cozy relationship was back to normal after about four days.  Best buddies again!

I caught them grooming each other last night - yay!

Now, to figure out how to make them both like Max's new "special food"...