Is your cow more likely to lie down the longer its been standing?
This seems like a really silly question, it seems like the longer something has been standing, the more likely it will be to lie down. But in fact, the answer is not so simple, and the question isn't so silly. Instead of asking whether the cow is likely to lie down the longer it's been standing, however, we should ask whether it's likely to stand the longer it's been lying down. A small, but important, distinction.
Tolkamp et al. "Are cows more likely to lie down the longer they stand?" Applied Animal Behavior Science, 2010.
(Is she going to lie down? How about now? Place your bets, gentlemen. Source)
Tolkamp may be an expert in studying cows, but even he readily admits that it can be "pretty boring." And looking at whether cows are more likely to sit or stand? Seems like a very boring way of driving yourself off the deep end. However, there is a method to the bovine madness.
Why do it? Because it's important for the cow's quality of life. Cows, you see, are prey animals. It is NOT in their best interest to show when they are not feeling well, say when a leg hurts. After all, a limping cow to any predator looks like dinner. They will walk without a limp until the last possible moment, which can mean they are beyond anything but major medical intervention. If the cow had shown a little pain, the herder might have been able to get the foot infection, say, before it got too far.
This means if you're the person who wants to keep healthy cows, you need to find ways to tell when a cow isn't up to its usual bovine self. But since a cow won't limp...what do you do?
You check and see how often it LIES DOWN. A cow that is unwell will lie down a lot more (to take weight off the bad leg, or to rest) than a cow that is well. But to be able to detect whether the cow is lying down more...you need to know how often cows lie down in general, and how likely they are to stand up, stay standing, or take a break.
Previous studies in this field utilized the simple method of holding the cow standing for a while (say, 5 hours), and then measuring how fast it lay down when you allowed it to. These studies determined that a cow was much more likely to lie down the longer it was standing.
Tolkamp didn't buy it. He reasoned that the method for keeping the cows up was artificial, and didn't provide a natural measure of cow behavior. It was time to observe real cows.
The authors looked at three groups of cows: pregnant moms housed indoors, shaggy pregnant cows wintering outdoors, and lactating dairy cows with their own stalls, but access to a yard. Cows were fitted with tracking bands on their feet that showed when they stood or lay down. Unfortunately, it turned out the calibration on the sensors...was not accurate. Luckily, they had video, but unluckily, this meant the authors spent many hours watching cows hang out. Sadly, I did not get to ask Tolkamp whether they had a soundtrack for video watching. I was really hoping that people watch cows stand to Metallica.
What did they find? There is no correlation between the length of time a cow is standing and the probability of its lying down. Cows are champion standers. If they've been standing, well, they are just as likely to keep standing. When your weight is distributed over all four feet and you don't really have knees, I guess it's easy to just lock 'em in place for the long haul.
However, the amount of time the cow was lying down DID increase the probability of its standing up. Why? Because cows get hungry. A cow cannot graze lying down, it has to be standing. And that means getting up, and getting up pretty often. If you had four stomachs, you'd need to eat a lot, too.
This means if you're trying to gauge whether your cow is ill, look not at whether your cow lies down. Instead, look to see whether it stands up. The importance of probability!