I have 2 un-neutered male siamese kittens. They are coming up 10 months old and we recently also got a puppy. They all seem to get on well and in fact one of the siamese seems to be the leader of the pack. However all of a sudden the cats seem to be peeing over the house instead of the litter tray. Anyone know why this is and what i could do to stop it? I would assume its to do with the puppy?

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It's a dominance thing peeing shows who the boss is
If your not keeping your entire boys for stud work I would take them to the Vets for the snip

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Mazpahs Siamese & Orientals

Sounds like a plan.

How old they have to be for that? poor things

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6 months most pets can be done then

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Yah castration is great, takes like 5 minutes!

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Pass me the snipperssss and a elastic band plzzz dawnyyy

Hang on, make the the other way round

Peeing everywhere can also be an insecurity thing in cats, i assume it has started since the pup arrived, can the cats get away from your pup, ie places they can go that he can't. Although appearing to get on well cats can be stressed by an over boisterous pup.

I am agree with that. Regarding neutering: novadays it could be done much earlier if it will help. Not all Vets keen on doing it thought ( but they do it to a feral kittens at any age).
Have a look:
Cat Fanciers' Association: Early Spay/Neuter in the Cat

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"Do not meddle in the affairs of cats, for they are subtle and will pee on your computer." --Bruce Graham
There are no rules, rules are only for people who fit inside a box, if you want to think out of the box there is no hope... Life has no Box. (Tony Howells)

Hehe I don't enjoy castration! Well, I don't do it lol but its a cool op because all the other neuter ops take like 15-30 mins but castration is so quick! Obviously good because the kitty is at less risk under anaesthetic.

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