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**Wildlife reservoirs include badgers and possibly deer in the Europe
 
**Wildlife reservoirs include badgers and possibly deer in the Europe
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*Pathogenesis and pathogenicity===
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*Pathogenesis and pathogenicity
**
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**Survival and multiplication in macrophages at primary site of infection due to prevention of phagosome-lysosome fusion
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**Mycobacteria are released from macrophages and also migrate within macrophages around the body
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**Waxy cell wall contributes to the host immune response to the mycobacteria and the development of lesions
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**Cell-mediated immune response with activated macrophages and sensitised T cells
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**Delayed-type hypersensitivity response with granuloma formation
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**Lesions contain macrophages, multinucleate giant cells and later a central area of caseous necrosis, giving a cheesy appearance
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*Clinical signs
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**Initially asymptomatic
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**Loss of condition
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**Cough and intermittent pyrexia with lung pathology
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**Tuberculous mastitis with transmission via milk
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*Diagnosis
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**Tuberculin test - comparative intradermal test
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**Avian and bovine tuberculin (purified protein derivative) is injected intradermally into two different clipped sites on the side of the neck
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**Skin thickness at these sites is compared before and 72 hours after the injection of tuberculin with calipers
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**Increases in skin thickness at the bovine PPD site of more than 4cm greater than the avian PPD site are seen as positive (reactor)
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**Blood tests including the gamma interferon assay are being developed
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