By Dr. Robert Tremblay

Close to 15 years ago, Neil Anderson, a veterinarian working with OMAFRA, used-time lapse photography to look at how dairy cows act in the barn when there are no people in the barn. That is when cows act most like themselves and also makes up the vast majority of their time. This approach helped him to identify parts of barns that were working for the cows and parts that weren’t working so well. Since then, the whole study of cow behavior has evolved to include several techniques but is still based on that approach. Let’s see what the cows tell us.

In the past month, the results of two studies have been made available. They use the same general method of observing the animals by recording their behavior in their natural environment (a barn or pen) after offering them options to see if they have any preference for certain choices.

The first study looked at the impact on bunk space on feeding behavior of low-ranking cows when there were dominant cows feeding at the bunk too. The researchers wanted to figure out how much of an impact eating at the bunk with dominant cows had on the feed intake of lower-ranking cows. The study included low-palatability ration placed next to high-palatability ration. This approach helps figure out if the quality of the ration will be attractive enough to let the cow overcome her concern about being so close to dominant cows. What the researchers found was that the low-ranking cows were more concerned about being close to dominant cows than they were about being forced to eat a lower-palatability ration. If they had a choice between eating a lower palatability ration or eating a more palatable ration beside a dominant cow, they chose to eat the low-palatability ration.

The researchers suggested that bunks should give cows at least 0.6 m of bunk space to try to overcome the challenges that lower-ranking cows have in getting access to the bunk. This will help the lower-ranking cows, but they admit that it won’t fully overcome their submissive behavior.

A second trial watched calves that were offered different bedding options. Other research clearly shows cows overwhelmingly avoided wet bedding. Researchers wanted to determine if calves have the same preference. Calves were offered a choice of lying down on concrete, dry sawdust or sawdust with 4 different levels of wetness. They found that 2-week-old Holstein calves would lie down for about 17 hours each day on the dry bedding. Calves lay down much less on the wet bedding; the wetter the bedding the less time they spent lying down. The differences were pretty remarkable. Calves used the least of the wet bedding for about 5 fewer hours. They didn’t lie down at all on the wettest sawdust. It was about the same for bare concrete; they wouldn’t lie down on it at all if they were given a choice. If you are looking to decrease stress in calves then making sure bedding is dry is a good start.