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