Summary
The
identification of species and biovars of Brucella field strains
isolated in outbreaks is essential to fully understand the epidemiology
of the disease and to trace sources of infection, thereby improving
the outcome of brucellosis eradication programmes. It is important
to identify the presence of Brucella strains in livestock
populations and to determine the presence of new strains that might
previously have been considered exotic. In this study, 732 Brucella
strains isolated from livestock were submitted for typing by the
Italian Istituti Zooprofilattici Sperimentali to the National
Reference Laboratory for brucellosis between 2001 and 2006. Animal
species affected, biovars typed and spatial distribution of isolates
are discussed. Brucella field strains were identified using
both conventional bacteriological methods and molecular techniques.
Species identification was performed using the AMOS (AbortusMelitensisOvisSuis)-polymerase
chain reaction. For biovar identification, amplification of omp2a,
omp2b and omp31 genes was performed, followed by restriction fragment
length polymorphism. Final biovar identification was performed by
growth in the presence of basic fuchsin and thionin, using the slide
agglutination test with Brucella A- and M- specific antisera.
Keywords
Brucella,
Brucellosis, Epidemiology, Isolation, Italy, Polymerase chain reaction,
Typing. |