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− | {{review}}
| + | #REDIRECT[[:Category:Mycoplasmas]] |
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− | {{toplink
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− | |backcolour =
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− | |linkpage =Bacteria
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− | |linktext =BACTERIA
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− | |pagetype=Bugs
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− | <br>
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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 and macrophages and prevent phagocytosis
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− | *Mycoplasmas induce proliferation of macrophages and 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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− | ===Clinical infections===
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− | *
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− | *Cause [[Peritoneal Cavity Inflammatory - Pathology#In sheep|peritonitis in sheep]] and [[Peritoneal Cavity Inflammatory - Pathology#In goats|peritonitis in goats]] and [[Peritoneal Cavity Inflammatory - Pathology#In pigs|peritonitis in pigs]]
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− | *Can be secondary to [[Respiratory Viral Infections - Pathology#In Cattle|IBR]]
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− | *[[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of pigs|Enzootic pneumonia of pigs]] caused by ''M. hyopneumoniae'' and ''M. hyorhinis''
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− | *[[Respiratory Bacterial Infections - Pathology#Contagious bovine pleuropneumonia (CBPP)|Contagious bovine pleuropneumonia]] caused by ''M. mycoides''
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− | *''M. bovis'', ''M. dispar'' and ''Ureaplasma'' in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of calves|Enzootic pneumonia of calves]]
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− | * May cause [[General Pathology - Chronic Inflammation#Lymphocytic Inflammation|lymphocytic chronic inflammation]] (peribronchiolar and perialveolar cuffing).
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− | *''M. felis'' in mild [[Respiratory Bacterial Infections - Pathology#Mycoplasma felis|respiratory infection]]
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− | *''M. ovipneumoniae'' in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of lambs|enzootic pneumonia of lambs]]
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− | *''M. hyosynovia'' and ''M. hyorhinis'' produce syndrome similar to [[Haemophilus species|Glasser's disease]] with milder expression, menigitis rare, [[Joints Inflammatory - Pathology#In Pigs|arthritis]] most consistent
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− | *In cattle [[Joints Inflammatory - Pathology#In Cattle|arthritis]]
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