
Brucellosis Vaccine for Cattle May Also Work
for BisonBy Linda Cooke November 4, 1997A new vaccine against brucellosis in cattle shows promise for protecting
bison against the contagious disease. Bison and elk are the last major sources
of brucellosis in the United States. The disease is caused by the bacterium Brucella abortus. In beef and
dairy cattle, it causes abortions, lessens fertility and reduces milk
production, costing the U.S. beef and dairy industry about $30 million
annually. Scientists with USDAs
Agricultural Research Service have been
checking the newest official vaccine containing B. abortus strain RB51
for its effectiveness and safety in bison. In an experiment at ARS
National Animal Disease Center in
Ames, Iowa, scientists vaccinated 10 female bison calves donated by the
U.S. Fish and Wildlife Service. The vaccinated bisons immune response was comparable to that of cattle
vaccinated with RB51. In earlier studies, ARS scientists demonstrated that RB51
protects cattle against brucellosis and that vaccinated cattle dont show
false signs of infection in blood tests. Based on the ARS studies, USDAs
Animal and Plant Health Inspection Service (APHIS) conditionally approved the new
vaccine for use in cattle. None of the RB51-vaccinated bison shed the live bacterium into the
environment. This demonstrates the biosafety of the vaccine in bison and helps
prevent accidental exposure to other wildlife. Moose, for instance, can die if
infected with virulent strains of B. abortus. ARS and APHIS researchers
are monitoring bison in Yellowstone National
Park to study how brucellosis is transmitted among free-living bison and
elk. Humans can get brucellosis from handling infected carcasses at slaughter or
from infected cows during calving. In humans, the disease is called undulant
fever and produces severe flu-like symptoms. Consumption of unpasteurized milk
and dairy products can also cause undulant fever. The November issue of Agricultural Research, ARS
monthly magazine, contains an article about the brucellosis research. The
article also is on the World Wide Web at: http://www.ars.usda.gov/is/AR/archive/nov97/buff1197.htm
Scientific contact: Steven C. Olsen, USDA-ARS,
Zoonotic Diseases Research
Unit, National Animal Disease Center, Ames, Iowa, phone: (515) 239-8393,
[email protected] U.S. Department of Agriculture | |