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===Histotoxic infections===
 
===Histotoxic infections===
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*Exotoxins cause local tissue necrosis and systemic effects which can be fatal
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*Exotoxins cause local tissue necrosis and systemic effects which can be fatal - toxaemia
 
*''C. chauvei'' and ''C. septicum'' present in muscle as latent spores which can germinate to cause infection
 
*''C. chauvei'' and ''C. septicum'' present in muscle as latent spores which can germinate to cause infection
 
*''C. novyi'' type B and ''C. haemolyticum'' have latent spores in the liver
 
*''C. novyi'' type B and ''C. haemolyticum'' have latent spores in the liver
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*Endospores persist in the soil
 
*Endospores persist in the soil
 
*Most ingested spores excreted in faeces, but some become dormant in tissues
 
*Most ingested spores excreted in faeces, but some become dormant in tissues
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*Tissue injury leads to reduced oxygen tensions allowing germination and replication of bacteria
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*Exotoxins cause local necrosis
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*Activated spores in the liver and muscles cause endogenous infections including blackleg, infectious necrotic hepatitis and bacillary haemoglobinuria
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*Inoculation of wounds causes exogenous infections including malignant oedema and gas gangrene
    
===''Clostridium chauvei''===
 
===''Clostridium chauvei''===
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*[[Muscles - inflammatory#Black leg|black leg]]:
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**Acute disease of cattle and sheep
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**Endogenous infection in young cattle with latent spores in muscles, activated by trauma
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**Exogenous infection via wounds in sheep of any age
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**Gangrenous cellulitis and myositis caused by exotoxins leads to rapid death
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**Skeletal muscle damage with lameness, swelling and crepitus due to gas accumilation
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**Dyspnoea due to lesions in tongue and throat muscles
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**Myocardial and diaphragmatic lesions can cause sudden death
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**Fluorescent antibody test for diagnosis
 
*Causes [[General Pathology - Necrosis#Gas Gangrene|gas gangrene]], along with [[Clostridium species#Clostridium septicum|''Clostridium septicum'']]
 
*Causes [[General Pathology - Necrosis#Gas Gangrene|gas gangrene]], along with [[Clostridium species#Clostridium septicum|''Clostridium septicum'']]
*Infects muscles causing[[Muscles - inflammatory#Black leg|black leg]]
      
===Clostridium novyi===
 
===Clostridium novyi===
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