Changes

==Characteristics==

==Characteristics==

''Brucella'' species are small, non-moltile, Gram negative coccobacilli. They are facultative intracellular pathogens. ''Brucella'' bacteria are aerobic and capnophilic. They are catalase positive and oxidase and urease positive, except for ''[[Brucella ovis]]''. They are modified Ziehl-Neelsen positive, forming clusters of red coccobacilli on smears. Some of the species require enriched media for growth. They are also non-haemolytic.

''Brucella'' species are small, non-moltile, Gram negative coccobacilli. They are facultative intracellular pathogens. ''Brucella'' bacteria are aerobic and capnophilic. They are catalase positive and oxidase and urease positive, except for ''Brucella ovis''. They are modified Ziehl-Neelsen positive, forming clusters of red coccobacilli on smears. Some of the species require enriched media for growth. They are also non-haemolytic.

Smooth colonies of ''B. abortus, B. melitensis'' and ''B. suis'' are small, glistening, blue and translucent after incubation for 3-5 days, and become opaque with age. Rough colonies of ''B. ovis'' and ''B. canis'' are dull, yellow, opaque and friable. Slide agglutination with speicific antisera can detect important antigens. Oxidative metaboloic rates can differentiate between species and ''B. abortus'' is lysed by specific bacterophages.

Smooth colonies of ''[[Brucella abortus|B. abortus]], [[Brucella melitensis|B. melitensis]]'' and ''[[Brucella suis|B. suis]]'' are small, glistening, blue and translucent after incubation for 3-5 days, and become opaque with age. Rough colonies of ''B. ovis'' and ''[[Brucella canis|B. canis]]'' are dull, yellow, opaque and friable. Slide agglutination with speicific antisera can detect important antigens. Oxidative metaboloic rates can differentiate between species and ''[[Brucella abortus|B. abortus]]'' is lysed by specific bacterophages.

==Pathogenesis==

==Pathogenesis==