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*Pathogens belong to the ''Mycoplasma'' and ''Ureaplasma'' genera
 
*Pathogens belong to the ''Mycoplasma'' and ''Ureaplasma'' genera
*Cause many diseases including contagious bovine pleuropneumonia
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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
 
*Non-pathogenic mycoplasmas present in the rumen
 
*Non-pathogenic mycoplasmas present in the rumen
 
*Live on mucous membranes of oronasal cavity, conjunctiva and intestines
 
*Live on mucous membranes of oronasal cavity, conjunctiva and intestines
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*Stress factors and concurrent disease may predispose to tissue invasion
 
*Usually host-specific
 
*Usually host-specific
 
*Limited survival in the environment
 
*Limited survival in the environment
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====Characteristics===
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===Characteristics===
    
*Smallest free-living prokaryotic organism
 
*Smallest free-living prokaryotic organism
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*Colonies have a fried egg appearance
 
*Colonies have a fried egg appearance
 
*Most are facultative anaerobes
 
*Most are facultative anaerobes
*''Ureaplasmas'' produce urease, whereas ''Mycoplasmas'' do not metabolise urea
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*Serolgy is required for specific identification
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*Growth inhibition tests using specific antisera can be used as well as fluorescent antibody tests
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*Mycoplasmas induce proliferation of macrophages and monocytes, and release of cytokines such as TNF and interleukins
 
*Mycoplasmas induce proliferation of macrophages and monocytes, and release of cytokines such as TNF and interleukins
 
*Cause damage to cilia in the respiratory tract leading to pneumonia
 
*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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