Yup, this is what you are eating. Lactobacillus delbrueckii bulgaricus from your yoghurt.
What I really don't get about youghurt is the is the whole concept.
It's milk. It's gone off, really badly, and you still are planning on eating it.
Historically, I can see a reason. There you are, on your farm, and you have too much milk one day, and no fridge to keep it in. Food is in short supply, and when you get up the next day, you notice your milk has turned into this jelly-like substance with an odd smell. Still, there's nothing else to eat but mud so you close your eyes and eat the stuff.
Fast forward to the 21st century. We are taking perfectly good milk, deliberately allowing bacteria to grow in it, and then eating it. Gross.