it doesn't sound like he is willingly emptying them out but more that they are just leaking as if full...So it sounds as though they just need to be fully emptied.

Not sure if this might help but Woody's were always getting blocked and he was forever at the vets getting them unblocked.

So we strated to add some wheat bran to his food every day for extra fibre and that seems to do the trick.

Might be worth a try?

Thanks for all the replies

they do get a bone now and then (not that often though) but their poos are almost always solid... which is why I find it strange as they should be emptying out when they poo :s

I'll mention it to the vet and see what he says.... thanks