Rumens are awesome.

I never really appreciated it before, but a cow is basically a giant vat of bacteria that happens to be alive. We had yet another cow lab today at the dairy farm where we palpated and listened to the rumen and other assorted digestive pieces. The rumen, for non-cow people, is one of the 4 stomachs of a cow, and takes up about the entire left side of the animal (this picture doesn't begin to do it justice. It's HUGE.) It's where most of the fermentation of cow digestion goes on (read: lots of bacteria), and beyond that is what is referred to as a "Block III/IV issue"... I'm in Block I and don't care yet :) Still, we have to learn to palpate the rumen and listen to its normal rumen-y sounds, which is quite fun. The rumen normally contains several different layers of semi-digested food, which allows for a neat trick... if you push your hand into the side of the cow over the middle of the rumen, it actually leaves a dent for a minute, like a Tempur-Pedic mattress! The cows don't mind this, they barely looked up from lunch. The purpose of all this bacterial goodness is to provide protein and fatty acids to the vegetarian cows- most of the protein in their diet actually comes from digested rumen bacteria. Cool, right? Cows are really giant milk-producing bacterial colonies!

So the next time you have a glass of milk, thank the cow and all the billions of bacteria that helped produde it! :) (Or won't you be drinking milk again?)