Response from "Tube Audio" :

I have four feral 4 month old kittens living in my back yard. I
trapped them and then took them to the human society / spca last
week and got the tested, shots and fixed. The have been released
and are doing great.

Someone donated a cat condo to me, and it seems like the previous
owner might have rubbed or put catnip on the top.

Once in a while a kitten will jump to the top and rub its face
into the top of the cat condo and then start freaking out a bit.
When this happens the freaked out kitten will go up to another
kitten and kinda start attacking it, not sure if they are playing
out what.

Everyone already said it perfectly. The thing is you mentioned 2
fundamental things:

1. Feral

Even non-feral cats have a pecking order, feral cats I would assume
adhere to it much more strictly especially when they have grown up
together.

2. Catnip

Cats adore catnip assuming:

1. They are old enough to be affected by it.
2. They are affected by it at all.

Is there any way to get the catnip off? Take a damp towel and
wipe it down, or take a vacuum attachment to it?

I really wouldn't worry about this too much. However, I would like
to tell you this -- something to keep in mind. Kittens are a
handful. We have only had our Gabby for almost 2 months or so now I
guess and it has been an interesting time for all. There are times
we have wanted to boot him out the door then he does something that
melts our hearts.

So basically... unless you see an ear come flying off I really
wouldn't worry about their play. Although you should be aware of
their sounds. Low guttural sounds or long drawn out low mewing and
loud sharp short yowls are NOT good. The play MAY be getting too
rough. Just be there to help if things get RIDICULOUSLY out of hand
-- otherwise remember, a little domination is key to a structure.

$0.02 from a new cat's slave's perspective.

--
-Lost
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