
New Test Readied for Pig DiseaseBy Linda
McGraw February 17, 1999A new test promises help for lab
technicians and veterinarians trying to detect bacteria that lead to a costly
pig disease. Each year, atrophic rhinitis costs pork producers $17 million in
lost weight and delays to market. Pigs with this disease are also highly
susceptible to pneumonia. Two toxin-producing bacteria--Bordetella bronchiseptica and
Pasteurella multocida--are the culprits behind atrophic rhinitis. This
disease is highly contagious and spreads quickly among pigs in confinement
houses. P. multocida reduces long bone growth, causing shortened and
twisted snouts on severely infected pigs. But snout deformities are not always
obvious. Detecting bacteria quickly may help cut losses by allowing producers to
combine treatments including antibiotic therapy, vaccination, and depopulation.
Current diagnostic methods can take at least 5 to 7 days and arent always
reliable. ARS molecular microbiologist Karen B.
Register in Ames, Iowa, designed the test using probes made from the genetic
material of P. multocida and B. bronchiseptica. These probes
target the toxin-producing gene of P. multocida and a gene found in all
disease-causing strains of B. bronchispetica, in a nasal or tonsil swab
taken from live pigs. Bacteria in the samples are grown and placed on a
paper-like sheet of nylon. Any spot where B. bronchiseptica is present
turns pink. Any area containing toxin-producing P. multocida turns
purple. Results from this test are obtained within 3 days. ARS is the USDAs chief scientific
research agency. Scientific contact: Karen B. Register, ARS
Avian and Swine Respiratory
Research Unit, National Animal
Disease Center, Ames, Iowa, phone (515) 239-8275, fax (515) 239-8458,
[email protected]. U.S. Department of Agriculture | |