Editor's note: The following case was handled by Scott Crandell, dairy nutritionist in Mifflinburg, Pa.

An 800-cow dairy in Maryland was having a problem with displaced abomasums or DAs. Many of the cows developed the problem, including a fair number of first-calf heifers. “It was a very high percentage,” recalls the farm’s nutritionist, Scott Crandell.

The owners of the farm asked Crandell to look at the pre-partum transition ration. The TMR consisted of corn silage, grain mix, a little bit of haylage, and it was formulated to provide 4 pounds of hay per cow per day. The cows also had access to hay on a free-choice basis.

Another person was doing the dry-cow rations for the farm, so Crandell was there to provide an independent review. He found nothing wrong with the ration in terms of how it was being formulated and delivered to the cows. And, the cows’ body condition was adequate.

Crandell suspected all along that it had to do with the cows’ environment or eating activity.

Upon further investigation, the free-choice hay didn’t seem to be very “free-choice.” The round bales were wrapped so tight that the cows were having a hard time tearing them apart. The hay feeder wasn’t well-designed, in Crandell’s opinion. And, there weren’t any cows around the feeder, which was another red flag.

That suggested the cows weren’t getting enough bulk in their diets, which was curbing rumen fill.

So, Crandell asked the owners if they could add more hay to the TMR.

“All I did was ask them to double the hay in the mixer,” Crandell says. Each cow was now supposed to get 8 pounds of dry hay in the TMR rather than 4. Besides the TMR, hay was still provided on a free-choice basis.

The next week, Crandell drove onto the farm and, before he could park the vehicle, the owner walked toward him. Crandell rolled down the window on the passenger side, the owner leaned in, and said, “They’re gone.”

The DA problem was gone.

Again, this was a large dairy with 800 cows. Enough cows were freshening on a weekly basis that Crandell and the owner had the feedback they needed to tell if the ration change was working. On a smaller farm, it would take longer than that.