When you think about it, cows are pretty amazing creatures. They thrive by eating a bunch of stuff that would have no nutritional value for you and me. (Plus, magnets!)
Bacteria are a cow’s best friends
The reason this works for cows is that they are essentially a giant fermentation chamber on legs. They eat a bunch of roughage, drink some water, blend it all up, and then let the specialized bacteria in the rumen do their thing. Those bacteria digest the roughage and produce volatile fatty acids (VFAs) which is something the cow actually can use. So the cow feeds the bacteria and the bacteria feed the cow and everyone is happy.
Except when they’re not…
If something happens to the bacteria, the cow is full of fiber that it can’t do anything with. Even if you fix the problem that killed the bacteria in the first place (often a sudden diet change), that doesn’t magically repopulate the rumen. You still have a cow that is starving to death with a stomach full of food.
With time and luck, if not all of the good bacteria are dead, they may multiply and get back to full strength. Fingers crossed. But there are all kinds of things that can go wrong, and in the meantime, the cow is pretty miserable. What you need is a big bucket of the right bacteria that you can put straight into the cow’s stomach. But where are you going to find that?
Herd is the word
The answer is in the cow next door. Any other cow on a similar diet has a giant vat full of the exact bacterial soup you need. So you get what you need from a healthy cow, then pump that bacterial broth into the rumen of the sick cow, and now you have a fermentation vat on four legs again. That process is called transfaunation.
This whole process is possible when your healthy donor cow has a fistulated rumen. Essentially, that’s a rumen with a permanent porthole. When you need to transfaunate, you unscrew the cover on the side of the cow, siphon out some liquid, screw the cover back on, give the cow a few extra scritches for being good, and then send her back to the herd again.
The vet school kept a few fistulated cows and those cows weren’t bothered by their fistulas at all. They probably lived longer too. In a world where cows have to justify the cost of their feed, a fistulated cow is worth keeping around, even if it doesn’t have great milk production.
During Fun Facts Friday, I talk about something I think is interesting. Do you have questions? Suggestions for a future post? The urge to pick at Mackie’s feather casings? Add a comment below!
