[RomyH]

I have a 9month old Bernese Mountain Dog, who until recently has been a model dog - house trained within a couple weeks even.

But recently - for the past 8 nights has been soiling himself, several times a night. However during the day, he seems absolutely fine, eating normally, and asking to go out as he would normally.

Could this be separation anxiety rather than an illness?

[Sariss]

It could be - but you need to rule out medical cause first.
When you say soiling - is he urinating? If so, you should bring a urine sample into the vets to rule out infection. Often dogs will urinate inappropriately if they have a UTI.

[RomyH]

No, its everything, loads of wee, poos, and even diahrea? And tonight he's woken me up twice with barking loads, and wanting to go out, barking and then coming in again...

I will be checking with the vets on Monday I think, as his companion is a much older lab ( 10 ) who displayed very erratic behavior ( scratching the doors until his paws bled and the glass fell out ) after the death of this one's predesesor? Is it possible that he's following a bad example? Despite the bad behavior stopping just a couple days after the newcomers arrival?

[MeeBee]

Take him into your vet. It could just be not being able to go anywhere. It could be a illness, or, if you aren't spending as much time with him as you did when you first got him, it could be loneliness. Talk to your vet. She/He Knows everything when it comes to animals.