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− | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
| + | #REDIRECT[[:Category:Brucella species]] |
− | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
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− | *''B. abortus'' occasionally in [[Joints - inflammatory#In Cattle|arthritis of cattle]]
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− | *Isolated from closed cases of [[Bursae and Tendons - inflammatory#Poll Evil and Fistulous Withers|Poll Evil and Fistulous Withers]]
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− | ===Overview===
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− | *Important zoonoses worldwide
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− | *Cause chronic granulomatous diseases
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− | ===Characteristics===
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− | *Small, non-moltile, Gram negative coccobacilli
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− | *Facultatice intracellular pathogens
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− | *6 species
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− | ===Pathogenesis and pathogenicity===
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− | *Penetrate nasal, oral or pharyngeal mucosa
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− | *Phagocytosed and carried to regional lymph nodes
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− | *Survive and multiply in cells of the reticulo-endothelial system
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− | *Inhibit lysosome-phagosome fusion
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− | *Lymph nodes enlarge (lymphatic and lymphoreticular hyperplasia) and inflammation is induced
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− | *Surviving organisms spread to other organs (liver, spleen, placenta) and cause granulomatous reactions
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− | *Eythritol is a growth stimulant and attracts the bacteria to the bovine placenta
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− | *Infection of foetus and abortion
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− | ===Clinical disease===
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− | ===Diagnosis===
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− | ===Control===
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− | *Serological testing of milk (Milk Ring Test) and beef cattle (Rose Bengal Plate Test)
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− | *Serological tests detect anti-lipopolysaccharide antibodies
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− | *LPS antigen present in virulent as well as some vaccine strains therefore vaccination may confuse serological testing
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− | *False positives due to cross-reaction with LPS in other bacteria
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− | *Vaccination:
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− | **Strain S19, a live vaccine, stimulating a cell-mediated immune response; vaccination of young animals; interferes with serological testing
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− | **Newer RB51 vaccine has no LPS O-antigen therefore not detcted by serological tests
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− | **Live attenuated ''Brucella melitensis'' vaccine to protect sheep and goats against ''B. melitensis''
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− | *Test and slaughter program has eradicated Brucellosis in the UK
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