Hi, sorry abou the disgusting subject title!

A couple of weeks ago my 9 month old Lab had green poo, she seemed ok in herself and it went in a couple of days, now my 4 month old has got it, we changed the dog food but she still has it and my 9 month old has got a bit of green in it again. They are both well in themselves.  Any ideas what it could be?

Thank you

I have found in the past it is colourants in the food - ive had red poo lol! :-D

This matter ;) has been discussed quite recently in this thread. 

Oh i didnt know that - luckily mine was just down to food colourings and dog chews :-d