I was in the garden today and I heard something resembling a sheep.
When I looked around I saw my dog (gsd) throwing up on the grass, I went over and he seemed ok and I guessed he was just getting rid of a piece of undigested bone.
He was pretty intent on sniffing what he'd don and I told him to come away and leave it alone.
When I came back 5 minutes later with a shovel of sand, I saw he'd eaten it.
So why the heck do they do that ?