This is a strange cat behavior problem and I don’t have a ready made answer. Or any solid answer except some guesses or more questions. The problem has been raised by one of the Catster visitors and we are going to try and find a solution because the Catster site can’t 😉
The cats are litter mates, siblings. They were always best friends and got on very well, grooming each other and so on. Their owners moved home. They had to fly to their new address which is in a different part of America. The cats were shipped by air to the new address. I am not sure if they were in the hold of the aircraft or in the cabin. I have presumed they were in the hold. After getting into their new home the siblings decided that they disliked, even hated each other. After several weeks they became more friendly but fell out of friendship. When one approaches the other he gets hissed at and swatted.
That is the scenario. What is the solution? What has happened?
We can’t find a solution until we know what has caused the change in behavior. In my experience when siblings fall out in such a way it is usually because of a change in their scent. They can no longer recognize each other. I will pursue that argument initially.
Cats, including siblings, recognize each other by their smell. I guess sight is also a factor but if a cat’s scent is removed, cats that at one time were friendly will no longer see this cat as a friend. The cat with no scent, or a different scent, becomes a complete stranger. It is as if a stray cat walked in off the street instead of a well loved sibling being in the room.
Because the sibling becomes a stranger he gets hissed at because he is intruding on the other siblings’ territory. If the scent of all the siblings is removed or changed the siblings are no longer siblings but strangers to each other. They have to adapt to get on. This is what appears to have happened. Initial hostility has given way to reluctant tolerance with the odd flare up. There is, at best, an uneasy peace.
I have to conclude that the scent given off by these siblings has not returned to the way it was when they lived together at their previous home.
If that is correct, and it might not be, what could cause a cat’s scent to change for a long time or permanently?
One possibility is the conditions under which they were shipped. The crates or environment in the aircraft may have given off a chemical that has been impregnated in the cats’ fur. It may have been ingested and is coming out of their skin.
Alternatively, they may have been vaccinated etc. and the vaccine has changed their scent. I have not heard of this happening but it seems to me to be a possibility albeit a very long shot indeed.
There may be something in the air in the new home that is masking the cats’ scent, which has confused the cats.
I presume that the cats’ owner is not bathing the cats regularly. If she is that would remove scent and cause the problem.
It may be the case that the cats went through a traumatic journey in the airplane when shipped to their new home. Alternatively, they may have suffered some sort of traumatic event at either of the airports. This may have left them in a state of defensive aggression towards anything and everything including each other. If they were in the hold of the aircraft one of them may have become upset and caused a breakdown in the group friendship.
What To Do
Reestablish their natural scents or try and find out if anything happened before, during and after the flight that may have impacted on their body scent and/or psyche. Then pursue a course of treatment that corrects the changes.