my cats tail shakes....

I have two male cats who are neutered and sometimes they will just walk up to a book shelf a door anything and shake their tail- ive actually put my hand behind them and nothing comes out so question 1: why is this happening??

question two is my cat Thumbs, he will pee in the litter box and he will squat a little, then sometime he will be standing and pee will shoot out straight back on the wall of the litter box so question 2: What the heck is this? It smells different and if he's spraying...he shouldn't be but its nice of him to do it in the litter box.
Hi
Well tail shaking is generally considered to be associated with excitement. My own cat will shake her tail rather quickly when a) she is watching birds in the garden or b) when we come home and she first sees us. So it may just be a sign of excitement and happiness. It isn’t anything to worry about (as long as you have checked that there are no fleas of mites in the area which may be causing irritation)

As for the second part of your question. Male cats will sometimes still spray even if they are neutered as they still sometimes feel need to scent mark their territory.

It is odd that he does it in his litter tray though, he may have some medical problem which causes it to happen involuntarily when he is urinating and may be worth having checked out. Other wise it may just be his way of making sure that this litter tray and area definitely smells of him and is therefore his. It is important that if you have more than one cat that you have two separate litter trays which are not near each other and are in areas where the cat can feel safe when using it. https://www.our-happy-cat.com/cat-litter-box.html

Best wishes Kate

P.S Gorgeous Cat

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