Of 8, 219 serum samples collected from Brucellosis-suspected dairy cows which were positive in rapid or plate agglutination test during 1976 to 1978. in Taiwan. One hundred and eighty-five cases were confirmed by both tube agglutination and comple-ment-fixation tests for Brucellosis-Positive. Of which, milk samples (109 Brucellosis-po-sitive cows) and several visceral organs (54 eradicated Brcellosis-positive cows) were taken for the isolation purpose. The milk samples were shown 68.8% isolation rates (75/ 109) in direct method, and 76.1% (83/109) in animal inoculation and enrichment method. The visceral organs were shown 53.7% isolation rates (29/54) in direct method, and 72.2% (39/54) in animal inoculation and enrichment method. All the isolates were iden-tified as Brucella abortus by biological tests, dye tolerance, serum agglutination tests and susceptibility In histopathologcal exam to guinea pigs.
The inoculated guinea pigs showed Various level of proliferation of retieuloendothelial cells in lymphoid organs in most cases. Multifocal necrosis associated with marked infiltration of neutrophils and lymphocytes, and mild proliferation of epitheloid cells were noticed in some cases .. In those inoculated guinea pigs, the pathogens concentrated highly in the hemo-lymphatic organs and lowly in the lung and the heart.