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| − | ===Overview===
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| − | *Pathogens belong to the ''Mycoplasma'' and ''Ureaplasma'' genera
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| − | *Cause many diseases especially respiratory diseases of farm animals including contagious bovine pleuropneumonia
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| − | *Can be involved in mastitis and conjunctivitis in cattle
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| − | *Implicated in respiratory and urinary tract diseases in dogs and cats
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| − | *Non-pathogenic mycoplasmas present in the rumen
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| − | *Live on mucous membranes of oronasal cavity, conjunctiva and intestines
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| − | *Stress factors and concurrent disease may predispose to tissue invasion
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| − | *Usually host-specific
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| − | *Limited survival in the environment
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| − | ===Characteristics===
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| − | *Smallest free-living prokaryotic organism
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| − | *Pleomorphic organisms
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| − | *Have no peptidoglycan cell wall
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| − | *Susceptible to dessication, heat and disinfectants
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| − | *Require enriched media containing animal protein, sterol and a source of DNA for growth
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| − | *Colonies have a fried egg appearance
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| − | *Most are facultative anaerobes
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| − | ===Pathogenesis and pathogenicity===
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| − | *Mycoplasmas adhere to host cells and produce toxins
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| − | *Some adhere to [[Neutrophils|neutrophils]] and macrophages and prevent phagocytosis
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| − | *Mycoplasmas induce proliferation of macrophages and [[[[Monocytes|monocytes]]]], and release of cytokines such as TNF and interleukins
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| − | *Cause damage to cilia in the respiratory tract leading to pneumonia
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| − | *Molecular mimicry allows some mycoplasmas to avoid the host immune response and may initiate immune-mediated disease
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| − | ===Diagnosis===
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| − | *Samples can be tested for the presence of mycoplasmas by fluorescent antibody techniques, peroxidase techniques and PCR
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| − | *Biochemical profiles such as urease production can be used for identification
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| − | *''Ureaplasmas'' produce urease, whereas ''Mycoplasmas'' do not metabolise urea
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| − | *Serolgy is required for specific identification including complement fixation tests, ELISA, agglutination tests and haemagglutination-inhibition tests
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| − | *Growth inhibition tests using specific antisera can be used as well as fluorescent antibody tests
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| − | ===Other mycoplasmas===
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| − | *''M. bovis'', ''M. dispar'' and ''Ureaplasma'' can be involved in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of calves|Enzootic pneumonia of calves]]
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| − | *''M. ovipneumoniae'' is implicated in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of lambs|enzootic pneumonia of lambs]]
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| − | *''M. felis'' may be involved in mild [[Respiratory Bacterial Infections - Pathology#Mycoplasma felis|respiratory infection]]
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| − | *Mycoplasmas may cause [[Chronic Inflammation - Pathology#Lymphocytic Inflammation|lymphocytic chronic inflammation]] (peribronchiolar and perialveolar cuffing)
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| − | *Cause [[Peritonitis#In sheep|peritonitis in sheep]], [[Peritonitis#In goats|peritonitis in goats]] and [[Peritonitis#In pigs|peritonitis in pigs]]
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| − | ==cattle==
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| − | **[[:Category:Mycoplasmas|'''''Mycoplasma spp.''''']]
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| − | ***May be respinsible for some chronic cases but difficult to prove as hard to isolate
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| − | ***Fibrinous polyarthritis
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| | [[Category:Bacteria]] | | [[Category:Bacteria]] |
| − | [[Category:To_Do_-_Bacteria]]
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