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|pagetitle =Mycoplasmas
 
|pagetitle =Mycoplasmas
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|pagebody =The Mycoplasmas are small free-living prokaryotic organisms. They cause many diseases, notably respiratory diseases in farm animals including [[Contagious Bovine Pleuropneumonia]]. 
 
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<categorytree mode=pages>Mycoplasmas</categorytree>
 
<categorytree mode=pages>Mycoplasmas</categorytree>
 
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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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[[Category:Bacterial Organisms]]
 
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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 - Pathology#In sheep|peritonitis in sheep]], [[Peritonitis - Pathology#In goats|peritonitis in goats]] and [[Peritonitis - Pathology#In pigs|peritonitis in pigs]]
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[[Category:Bacteria]]
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[[Category:To_Do_-_Bacteria]]
 
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