When i mentioned about Pedigree foods i was referring to their tinned meats rather than complete feed.

I've read the literature on complete feeds and i'm totally convinced that aside from obeisty and cancers that one hears/reads about - the preservatives (ethoxyquins) in dried complete feeds contribute through the build up of tartar to development of gum disease. HDA and HTA are the ones to look for in the ingredients i gather
http://www.avianweb.com/ethoxyquin.htm

I've got a dog that i can't give bones to [just won't be interested!], the butcher's pet-mince is a bit fatty i feel and so for the moment i'm giving tinned Pedigree Original. Both dogs love it but i wanted to know about possible long term effects. since putting them on meat and mixer i have noticed such a difference in their toileting and general behaviour that i'll never give a dog any complete feed again. My greyhound was rather constipated and my younger lurcher seemed to have a bladder problem. Due i believe to the long digestion rate of complete food.