sealPurdue News

April 1998

Pseudorabies outbreaks will affect 4-H swine shows

WEST LAFAYETTE, Ind. -- 4-H'ers and others in search of this year's grand champion hog need to be aware of a swine disease enjoying a resurgence in Indiana and elsewhere.

Cool, damp weather in parts of the United States has created an environment for the pseudorabies virus to thrive. Although the disease has been eradicated in several states, it still can wreak havoc in the upper Midwest and North Carolina. 4-H swine project members and others will need to ask questions and take sanitation precautions when visiting farms this spring.

Hogs are the natural host for pseudorabies, a viral disease they can sometimes carry without their owner's knowledge. Symptoms range from none to sudden death, according to Dr. John Johnston of the Indiana Board of Animal Health Swine Division. Severity of the disease depends on the age and immune status of the animal.

"It's a disease of the respiratory, reproductive and central nervous systems," Johnston said. In pigs under 3 weeks old, loss of appetite, incoordination, depression, vomiting, nervousness, diarrhea and convulsions may occur, followed by death of the entire litter. In older pigs, signs may be fever, loss of appetite, sneezing, coughing, pneumonia, convulsions and occasionally blindness. In sows, owners may see abortion or stillborn pigs.

It can affect other species, he said, including cattle, sheep, cats, dogs and wild animals. Signs in these animals are more severe. The Indiana Board of Animal Health lists incessant scratching to the point of mutilation as the most common symptom, but all typical swine symptoms may be seen. False rabies symptoms -- grinding teeth, excessive salivation, bellowing and excitement -- also may arise.

Pseudorabies cannot be transmitted to humans, and there is no danger to those eating the meat of pseudorabies-positive hogs, according to veterinarians at the Indiana Board of Animal Health.

The disease is spread primarily by nose-to-nose contact, Johnston said, but it also can live for a short time in manure on gates and other surfaces, so it can be picked up on boots and tracked to other pens or farms.

For this reason, said Clint Rusk, 4-H Youth Extension specialist at Purdue University, 4-H'ers and their families shouldn't go from farm to farm looking for a 4-H pig without cleaning boots and clothing between farms.

"There are plastic boots -- almost like baggies -- they can get at veterinary supply stores to wear over their shoes," he said. "They can wear a clean pair at each farm and then dispose of them."

Other recommendations Rusk had for 4-H'ers include:

  • Check with your county Cooperative Extension Service office for specific requirements to show hogs in your county. Also find out if your county will have a "terminal" show, after which all animals must be sold for slaughter, because you may need to purchase an extra animal for state fair exhibition.
  • If you're planning to show swine at the state fair, check health requirements for those swine shows.
  • Before buying a hog, make sure it's been tested for pseudorabies (PRV tested) and has a health certificate.
  • Find out from your state veterinarian if hogs vaccinated for pseudorabies can be exhibited and sold.
  • Isolate new hogs from any other hogs on the farm until they can be tested.
  • Find out if hogs going to shows must be tested and what the valid PRV test period is. In Indiana, for example, every hog going to a show must be tested, and animals cannot be unloaded at the fairgrounds without the appropriate paperwork.
  • Contact your local veterinarian or your state veterinarian for more information on pseudorabies, its control and testing.

CONTACTS: Johnston, (317) 227-0310; e-mail,
Rusk, (765) 494-8427; e-mail,

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