Editor's note: This case was handled by Timothy Johnson, an independent dairy nutritionist from Noblesville, Ind.
When you run into "the worst-case scenario," it gets your attention and makes you even more vigilant against it happening again.
That is what happened to Timothy Johnson a couple of years ago. While working as an extension dairy nutritionist at Purdue University, he and some other members of a multi-disciplinary team visited a 300-cow dairy operation in northeast Indiana. The farm had been experiencing production- and health-related problems and requested the visit.
When the team arrived, it was obvious there were problems with the hay-crop silage stored in a bunker silo. The silage, comprised mainly of alfalfa with some grass, had a putrid smell and seemed too wet, almost to the point where you could squeeze a few drops of water out of a handful of the silage.
After sending samples to a lab, their worst fears were confirmed. Lactic acid was low at 4.5 percent, when Johnson would have preferred to see it at 6 percent to 8 percent. Meanwhile, acetic acid was too high at 3.5 percent and butyric acid was especially troubling at 1.5 percent to 2 percent. (Butyric acid should be less than 0.1 percent.)
The high butyric acid level was throwing cows off feed, which explained why the farm was experiencing an increase in metabolic problems. This was especially obvious with the newly fresh cows. Close to half of the cows that calved in April of that year were having problems with retained placenta, displaced abomasums, milk fever and/or metritis. Things got worse with the arrival of spring. Perhaps the warmer temperatures were making the silage even more unstable.
And, the farm also was fighting something it had never seen before — hemorrhagic bowel syndrome. Five cows were afflicted with HBS that particular April.
The team members suggested that the farm dilute the tainted silage with other feed until new-crop silage became available in the summer. Over the next couple of months, milk production rose from 45 pounds (per cow per day) on average to 60 pounds.
It took a little longer to get the metabolic problems under control, but DAs have dropped from 15 to 17 percent to the current level of 5 to 6 percent. Hemorrhagic bowel syndrome has disappeared. And, production is now up to 74 pounds per cow per day.
This past July, Johnson spoke to the herd's nutritionist and got an update. The herd nutritionist reflected on the underlying cause of the problem — people putting up hay that is too wet for ensiling — and said it is an ongoing problem that he continues to face on other farms. Perhaps a big thunderstorm is imminent, and people feel compelled to chop the hay and haul it to the bunker ASAP. It's totally understandable, but can present problems down the road if the hay hasn't dried out enough.
To make this a "teachable moment" for other people, Johnson is not shy about mentioning this case, and particularly hemorrhagic bowel syndrome.
When you see the "pinnacle" of nutritional problems, he says, it gives you a heightened sense of urgency to the warning signs. Those warning signs include a putrid smell to the silage, along with an uptick in metabolic problems and lower dry-matter intake among the newly fresh cows. (No, the team did not test for a common feed-borne mold, Aspergillus fumigatus, that is thought to be behind many of the cases of hemorrhagic bowel syndrome. But, by phasing out the tainted silage in this case, they were able to accomplish the same result.)
Having a "worse-case scenario" is sometimes needed to get people's attention.