University of Minnesota

Dairy Initiatives

Dairy

Department of Animal Science

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Look Out for JHS

SANDRA GODDEN, TREVOR AMES, ROD FRANK
College of Veterinary Medicine
University of Minnesota

Jejunal hemorrhage syndrome (JHS), a deadly digestive tract disease, has been reported with increasing frequency in adult dairy cows in Minnesota over the past three years. Also referred to as hemorrhagic bowel syndrome or acute hemorrhagic enteritis of the small intestine, the disease is uncommon but can have a serious economic impact on affected herds.

Cause
No one knows for sure what causes JHS. One hypothesis is that it's the result of Clostridium perfringens Type A bacteria multiplying rapidly and producing toxins under conditions of high carbohydrate and protein substrate availability in the digestive tract. These conditions can be caused by the same factors that lead to ruminal acidosis (feeding excess amounts of fermentable carbohydrates, insufficient effective fiber and/or inadequate rumen fiber mat, or ration sorting by cows). A second hypothesis is that cows get JHS from eating poor quality, poorly fermented silage that has accumulated harmful molds, clostridial or other harmful bacteria, and possibly their toxins.

Risk Factors
JHS has been diagnosed in every season and in every dairy region in the state, in big herds and small, in cows in free-stall and tie-stall facilities, and on farms with a wide variety of feeding systems. It seems to be more common in fall and winter, in herds of 100 cows or more, and in herds fed total mixed rations (TMR), but there have not been enough cases to show a strong correlation with any of these variables.

What Can I Do?
It's hard to control a problem when the cause is not clear. But based on the hypotheses about cause, there are some things you can do to prevent JHS or solve a JHS problem in your herd:

  • Work with a nutritionist to ensure that rations include only high-quality, well-fermented forages.
  • Manage feed to prevent slug feeding and sorting by cows.
  • Feed a ration balanced with adequate effective fiber to maintain good rumen health and integrity of the rumen mat.
  • Check silage for obvious spoilage or inadequate fermentation. Discontinue feeding poorly fermented or spoiled forages to close-up and milking cows if another source of higher quality forages can be located. If alternate forage sources are limited, dilute the poorer forage out with higher quality forages.
What About Vaccination?
Vaccination cannot be recommended at the present time. For one thing, we don't know whether Clostridium perfringens Type A is the causative organism, or which specific toxin is responsible for JHS. Additionally, vaccines can be expensive and can cause adverse reactions including milk drop and premature calving. There are no studies available to demonstrate efficacy of vaccination to prevent JHS.

What it looks like:

Cows with JHS may simply suddenly drop dead. Or they may:

  • be down and semiconscious
  • be standing, but very weak and pale
  • stop eating
  • show a severe drop in milk production
  • bloat
  • have decreased fecal output, tarry stools, or bloody diarrhea.

Some 85 to 100 percent of affected animals die within 24 to 36 hours of the onset of clinical signs.


D A I R Y    I n i t i a t i v e s    N E W S L E T T E R
Volume 11    Issue 2    Summer 2002