UM takes Johne's message on the road

St. Paul, Minn.-

Researchers from the University of Minnesota (UM) College of Veterinary Medicine are hitting the road to deliver a message to veterinarians and producers about the control of Johne's disease in the state.

Johne's disease afflicts cattle by disrupting nutrient absorption, whichleads to chronic weight loss and, eventually, death. Because current testingcannot detect Johne's until a cow is 2-3 years old, the disease has spreadworldwide.

Scott Wells, DVM, Ph.D., a Johne's expert and epidemiologist with UM'sveterinary college, says more than half of Minnesota's dairy herds haveinfected cattle. Annual economic losses from Johne's disease in the U.S.have been estimated at $220 million.

To help control the spread of the disease, this year the Minnesota Boardof Animal Health (MBAH) received funds from the state legislature for aJohne's Disease Control Program and contracted with Wells and other UM researchersto bring information about disease control and current Johne's researchto veterinarians and dairy producers across the state.

In addition, grants from the Minnesota Rapid Agricultural Response Fundhave provided funds for research to better understand how to control thespread of Johne's disease.

"Johne's disease is a real threat to Minnesota's dairy industry,"Wells says. "The college of veterinary medicine is working hard toadvance our understanding of the disease and to bring this information toveterinarians and producers to assist them in control, and eventually eradication,of Johne's disease in Minnesota."

The first meeting was in Nicollet. The next meetings are slated for Rochester,Fergus Falls and St. Cloud.

The university reports that Johne's disease is economically importantto dairy farms, but often not noticed. Here are facts about the diseaseto consider.

* Many infected herds lose over $200 per cow in inventory peryear (USDA-APHIS study), mostly due to premature culling and lost milk production.

* The long incubation period (two to six years from infectionto disease onset) masks the impact of disease to producers, though infectedcows can transmit infection to other cattle before showing signs of diseaseand/or testing positive for Johne's.

* Johne's disease can be controlled.

* Most herds are infected through purchase of infected cattle.

* On infected farms, transmission occurs primarily through fecal-oralroutes, especially to susceptible young heifer calves.

* Disease control involves preventing heifer calves from exposureto manure from adult cows (with special focus on calving area and segregatedheifer rearing).

* The first step in control of Johne's disease is for producersto identify whether their dairy herds are infected.

For herds in the state, the MBAH will:

Test a random sample of 30 cows in a producer's herd to identify herdinfection status (the board also helps pay for lab costs of tests).

If a herd tests positive, an MBAH district veterinarian will visit thefarm and evaluate the key risks for spreading infection on the farm.