
I don't think it's poo in there :D
Apparently it is an oily secretion that is contained in the 2 sacs either side, when the dog poos, the sphincter muscles squeeze the anal sacs and force the oily contents onto the surface of the stool.......nice:rolleyes: This is presumably what gives it an enticing aroma to other dogs so that they are attracted to sniffing when walking by
They are often referred to as scent glands as when dogs 'greet' each other this is in fact what they are smelling....makes sense really.....if you're a dog

Edited to say that I was obviously posting at the same time as JG