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Created page with '{{review}} ===Overview=== *Pathogens belong to the ''Mycoplasma'' and ''Ureaplasma'' genera *Cause many diseases especially respiratory diseases of farm animals including conta…'
{{review}}
===Overview===
*Pathogens belong to the ''Mycoplasma'' and ''Ureaplasma'' genera
*Cause many diseases especially respiratory diseases of farm animals including contagious bovine pleuropneumonia
*Can be involved in mastitis and conjunctivitis in cattle
*Implicated in respiratory and urinary tract diseases in dogs and cats
*Non-pathogenic mycoplasmas present in the rumen
*Live on mucous membranes of oronasal cavity, conjunctiva and intestines
*Stress factors and concurrent disease may predispose to tissue invasion
*Usually host-specific
*Limited survival in the environment
===Characteristics===
*Smallest free-living prokaryotic organism
*Pleomorphic organisms
*Have no peptidoglycan cell wall
*Susceptible to dessication, heat and disinfectants
*Require enriched media containing animal protein, sterol and a source of DNA for growth
*Colonies have a fried egg appearance
*Most are facultative anaerobes
===Pathogenesis and pathogenicity===
*Mycoplasmas adhere to host cells and produce toxins
*Some adhere to [[Neutrophils - WikiBlood|neutrophils]] and macrophages and prevent phagocytosis
*Mycoplasmas induce proliferation of macrophages and [[[[Monocytes - WikiBlood|monocytes]]]], and release of cytokines such as TNF and interleukins
*Cause damage to cilia in the respiratory tract leading to pneumonia
*Molecular mimicry allows some mycoplasmas to avoid the host immune response and may initiate immune-mediated disease
===Diagnosis===
*Samples can be tested for the presence of mycoplasmas by fluorescent antibody techniques, peroxidase techniques and PCR
*Biochemical profiles such as urease production can be used for identification
*''Ureaplasmas'' produce urease, whereas ''Mycoplasmas'' do not metabolise urea
*Serolgy is required for specific identification including complement fixation tests, ELISA, agglutination tests and haemagglutination-inhibition tests
*Growth inhibition tests using specific antisera can be used as well as fluorescent antibody tests
===[[Respiratory Bacterial Infections - Pathology#Contagious bovine pleuropneumonia (CBPP)|Contagious bovine pleuropneumonia]]===
*[[Respiratory Bacterial Infections - Pathology#Contagious bovine pleuropneumonia (CBPP)|Contagious bovine pleuropneumonia]] is caused by ''M. mycoides'' subsp. ''mycoides'' small colony type
*A severe contagious disease of cattle
*Endemic in Africa, the Middle East and Asia
*Aerosol transmission by close contact with clinically or subclinically affected animals
*Severity depends on strain and host susceptibility
*Slow spread of infection
*50% morbidity; mortality rate high in severe outbreaks
*Large colony type causes pleuropneumonia, mastitis, septicaemia and polyarthritis
*Clinical signs
**Acute onset fever, anorexia, depression, lowered milk yield, hyperpnoea, coughing and a mucopurulent nasal discharge
**Dyspnoea occurs with abducted elbows and extended necks and an expiratory grunt
**Can be fatal within 1-3 weeks
**Calves may suffer from [[Joints Inflammatory - Pathology#In Cattle|arthritis]], synovitis and endocarditis
*Gross pathology
**Marbled appearance to lungs with consolidated grey and red lobules separated by emphysematous areas
**Serofibrinous pleural fluid
**Necrotic foci surrounded by fibrous capsules in chronic cases act as source of infection
*Diagnosis
**Clinical signs and post-mortem appearance
**PCR on pleural fluid, lung tissue, regional lymph nodes or bronchoalveolar lavage fluid
**Fluorescent antibody test
**Serological tests such as serum agglutination, haemagglutination, complement fixation, ELISA
*Treatment and control
**Slaughter of affected cattle in counries where the disease is exotic
**Movement restrictions, quaranteen and slaughter of carrier animals in endemic countries
**Vaccination in endemic regions
===''Mycoplasma bovis''===
*Causes severe pneumonia in calves as a primary pathogen
*Can occur secondarily to ''Pasteurella'' and ''Mannheimia'' and [[Respiratory Viral Infections - Pathology#In Cattle|IBR]]
*Associated with [[Joints Inflammatory - Pathology#In Cattle|arthritis]] and mastitis
*Mastitis associated with a severe drop in milk yield and a purulent discharge
===Contagious agalactia of sheep and goats===
*Severe febrile disease of sheep and goats in parts of Europe, Africa, Asia
*Caused by ''M. agalactiae''
*Mastitis, arthritis and conjunctivitis following parturition
*Causes abortion
*Fatal pneumonia in young animals
*Shed in milk; localised in supramammary lymph nodes
*Inactivated, attenuated vaccines available
===Contagious caprine pleuropneumonia===
*Caused by ''M. capricolum'' subsp. ''capricolum'; occasionally ''M. mycoides'' subsp. ''capri'' or ''M. mycoides'' subsp. ''mycoides''
*Occurs in Africa and Turkey
*Pneumonia, fibrinous pleurisy, pleural exudate, consolidated and emphysematous lungs
*Aerosol transmission; highly contagious
*Identified by growth inhibition disc tests
*Inactivated vaccines available
*''M. mycoides'' subsp. 'mycoides'' causes septicaemia, pleuropneumonia, arthritis and mastitis in goats
===[[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of pigs|Enzootic pneumonia of pigs]]===
*[[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of pigs|Enzootic pneumonia of pigs]] caused by ''M. hyopneumoniae''
*Occur in unfavourable conditions with poor ventilation, overcrowding and temperature fluctuations
*Stunted growth rates, coughing and occasionally respiratory distress
*Consolidation in apical and cardiac lung lobes
*Immunofluorescence of lung tissue and complement fixation test or ELISA used for identification
*Treatment includes in-feed antibiotics such as tylosin, lincomycin and tiamulin
*Absent in specific-pathogen-free herds
===''M. hyorhinis'' and ''M. hyosynoviae'' of pigs===
*''M. hyosynovia'' and ''M. hyorhinis'' produce syndromes similar to [[Haemophilus parasuis|Glasser's disease]] with milder expression, rarely menigitis and [[Joints Inflammatory - Pathology#In Pigs|arthritis]]
*''M. hyorhinis causes a chronic progressive polyserositis in pigs under 10 weeks old
*A fever, laboured breathing, lameness and swollen joints occur
*Serofibrinous pleurisy, pericarditis and [[Peritoneal Cavity Inflammatory - Pathology#In pigs|peritonitis]] occur
*Treatment includes tylosin and lincomycin
*''M. hyorhinis'' causes a polyarthritis in pigs of 10-30 weeks old, leading to transient lameness
===Mycoplasmas of poultry===
*''M. gallisepticum''
**Causes chronic repsiratory disease in chickens and infectious sinusitis in turkeys
**Transmission via the egg and aerosol
**Reduced egg production
**Identification by serum plate agglutination test, haemagglutination inhibition and ELISA
**Controlled in specific-pathogen-free flocks
**Modified live vaccines and bacterins available
*''M. meleagridis''
**Hatching problems; airsacculitis in young poults; joint and bone deformities in growers; poor growth rates
**Transmitted mainly via eggs and semen
**Serum plate agglutination test for identification
**In-water tylosin for first 10 days of life
**Eggs can be dipped in tylosin
*''M synoviae''
**Causes infectious synovitis in chickens and turkeys
**Transmitted by aerosol
**Synovitis, arthritis, respiratory disease
**Confirmation by isolation or serology
**In-feed tetracycline
**Eradication through specific-pathogen-free flocks
===Other mycoplasmas===
*''M. bovis'', ''M. dispar'' and ''Ureaplasma'' can be involved in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of calves|Enzootic pneumonia of calves]]
*''M. ovipneumoniae'' is implicated in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of lambs|enzootic pneumonia of lambs]]
*''M. felis'' may be involved in mild [[Respiratory Bacterial Infections - Pathology#Mycoplasma felis|respiratory infection]]
*Mycoplasmas may cause [[Chronic Inflammation - Pathology#Lymphocytic Inflammation|lymphocytic chronic inflammation]] (peribronchiolar and perialveolar cuffing)
*Cause [[Peritoneal Cavity Inflammatory - Pathology#In sheep|peritonitis in sheep]], [[Peritoneal Cavity Inflammatory - Pathology#In goats|peritonitis in goats]] and [[Peritoneal Cavity Inflammatory - Pathology#In pigs|peritonitis in pigs]]
[[Category:Infectious_Agents]]
===Overview===
*Pathogens belong to the ''Mycoplasma'' and ''Ureaplasma'' genera
*Cause many diseases especially respiratory diseases of farm animals including contagious bovine pleuropneumonia
*Can be involved in mastitis and conjunctivitis in cattle
*Implicated in respiratory and urinary tract diseases in dogs and cats
*Non-pathogenic mycoplasmas present in the rumen
*Live on mucous membranes of oronasal cavity, conjunctiva and intestines
*Stress factors and concurrent disease may predispose to tissue invasion
*Usually host-specific
*Limited survival in the environment
===Characteristics===
*Smallest free-living prokaryotic organism
*Pleomorphic organisms
*Have no peptidoglycan cell wall
*Susceptible to dessication, heat and disinfectants
*Require enriched media containing animal protein, sterol and a source of DNA for growth
*Colonies have a fried egg appearance
*Most are facultative anaerobes
===Pathogenesis and pathogenicity===
*Mycoplasmas adhere to host cells and produce toxins
*Some adhere to [[Neutrophils - WikiBlood|neutrophils]] and macrophages and prevent phagocytosis
*Mycoplasmas induce proliferation of macrophages and [[[[Monocytes - WikiBlood|monocytes]]]], and release of cytokines such as TNF and interleukins
*Cause damage to cilia in the respiratory tract leading to pneumonia
*Molecular mimicry allows some mycoplasmas to avoid the host immune response and may initiate immune-mediated disease
===Diagnosis===
*Samples can be tested for the presence of mycoplasmas by fluorescent antibody techniques, peroxidase techniques and PCR
*Biochemical profiles such as urease production can be used for identification
*''Ureaplasmas'' produce urease, whereas ''Mycoplasmas'' do not metabolise urea
*Serolgy is required for specific identification including complement fixation tests, ELISA, agglutination tests and haemagglutination-inhibition tests
*Growth inhibition tests using specific antisera can be used as well as fluorescent antibody tests
===[[Respiratory Bacterial Infections - Pathology#Contagious bovine pleuropneumonia (CBPP)|Contagious bovine pleuropneumonia]]===
*[[Respiratory Bacterial Infections - Pathology#Contagious bovine pleuropneumonia (CBPP)|Contagious bovine pleuropneumonia]] is caused by ''M. mycoides'' subsp. ''mycoides'' small colony type
*A severe contagious disease of cattle
*Endemic in Africa, the Middle East and Asia
*Aerosol transmission by close contact with clinically or subclinically affected animals
*Severity depends on strain and host susceptibility
*Slow spread of infection
*50% morbidity; mortality rate high in severe outbreaks
*Large colony type causes pleuropneumonia, mastitis, septicaemia and polyarthritis
*Clinical signs
**Acute onset fever, anorexia, depression, lowered milk yield, hyperpnoea, coughing and a mucopurulent nasal discharge
**Dyspnoea occurs with abducted elbows and extended necks and an expiratory grunt
**Can be fatal within 1-3 weeks
**Calves may suffer from [[Joints Inflammatory - Pathology#In Cattle|arthritis]], synovitis and endocarditis
*Gross pathology
**Marbled appearance to lungs with consolidated grey and red lobules separated by emphysematous areas
**Serofibrinous pleural fluid
**Necrotic foci surrounded by fibrous capsules in chronic cases act as source of infection
*Diagnosis
**Clinical signs and post-mortem appearance
**PCR on pleural fluid, lung tissue, regional lymph nodes or bronchoalveolar lavage fluid
**Fluorescent antibody test
**Serological tests such as serum agglutination, haemagglutination, complement fixation, ELISA
*Treatment and control
**Slaughter of affected cattle in counries where the disease is exotic
**Movement restrictions, quaranteen and slaughter of carrier animals in endemic countries
**Vaccination in endemic regions
===''Mycoplasma bovis''===
*Causes severe pneumonia in calves as a primary pathogen
*Can occur secondarily to ''Pasteurella'' and ''Mannheimia'' and [[Respiratory Viral Infections - Pathology#In Cattle|IBR]]
*Associated with [[Joints Inflammatory - Pathology#In Cattle|arthritis]] and mastitis
*Mastitis associated with a severe drop in milk yield and a purulent discharge
===Contagious agalactia of sheep and goats===
*Severe febrile disease of sheep and goats in parts of Europe, Africa, Asia
*Caused by ''M. agalactiae''
*Mastitis, arthritis and conjunctivitis following parturition
*Causes abortion
*Fatal pneumonia in young animals
*Shed in milk; localised in supramammary lymph nodes
*Inactivated, attenuated vaccines available
===Contagious caprine pleuropneumonia===
*Caused by ''M. capricolum'' subsp. ''capricolum'; occasionally ''M. mycoides'' subsp. ''capri'' or ''M. mycoides'' subsp. ''mycoides''
*Occurs in Africa and Turkey
*Pneumonia, fibrinous pleurisy, pleural exudate, consolidated and emphysematous lungs
*Aerosol transmission; highly contagious
*Identified by growth inhibition disc tests
*Inactivated vaccines available
*''M. mycoides'' subsp. 'mycoides'' causes septicaemia, pleuropneumonia, arthritis and mastitis in goats
===[[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of pigs|Enzootic pneumonia of pigs]]===
*[[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of pigs|Enzootic pneumonia of pigs]] caused by ''M. hyopneumoniae''
*Occur in unfavourable conditions with poor ventilation, overcrowding and temperature fluctuations
*Stunted growth rates, coughing and occasionally respiratory distress
*Consolidation in apical and cardiac lung lobes
*Immunofluorescence of lung tissue and complement fixation test or ELISA used for identification
*Treatment includes in-feed antibiotics such as tylosin, lincomycin and tiamulin
*Absent in specific-pathogen-free herds
===''M. hyorhinis'' and ''M. hyosynoviae'' of pigs===
*''M. hyosynovia'' and ''M. hyorhinis'' produce syndromes similar to [[Haemophilus parasuis|Glasser's disease]] with milder expression, rarely menigitis and [[Joints Inflammatory - Pathology#In Pigs|arthritis]]
*''M. hyorhinis causes a chronic progressive polyserositis in pigs under 10 weeks old
*A fever, laboured breathing, lameness and swollen joints occur
*Serofibrinous pleurisy, pericarditis and [[Peritoneal Cavity Inflammatory - Pathology#In pigs|peritonitis]] occur
*Treatment includes tylosin and lincomycin
*''M. hyorhinis'' causes a polyarthritis in pigs of 10-30 weeks old, leading to transient lameness
===Mycoplasmas of poultry===
*''M. gallisepticum''
**Causes chronic repsiratory disease in chickens and infectious sinusitis in turkeys
**Transmission via the egg and aerosol
**Reduced egg production
**Identification by serum plate agglutination test, haemagglutination inhibition and ELISA
**Controlled in specific-pathogen-free flocks
**Modified live vaccines and bacterins available
*''M. meleagridis''
**Hatching problems; airsacculitis in young poults; joint and bone deformities in growers; poor growth rates
**Transmitted mainly via eggs and semen
**Serum plate agglutination test for identification
**In-water tylosin for first 10 days of life
**Eggs can be dipped in tylosin
*''M synoviae''
**Causes infectious synovitis in chickens and turkeys
**Transmitted by aerosol
**Synovitis, arthritis, respiratory disease
**Confirmation by isolation or serology
**In-feed tetracycline
**Eradication through specific-pathogen-free flocks
===Other mycoplasmas===
*''M. bovis'', ''M. dispar'' and ''Ureaplasma'' can be involved in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of calves|Enzootic pneumonia of calves]]
*''M. ovipneumoniae'' is implicated in [[Respiratory Bacterial Infections - Pathology#Enzootic pneumonia of lambs|enzootic pneumonia of lambs]]
*''M. felis'' may be involved in mild [[Respiratory Bacterial Infections - Pathology#Mycoplasma felis|respiratory infection]]
*Mycoplasmas may cause [[Chronic Inflammation - Pathology#Lymphocytic Inflammation|lymphocytic chronic inflammation]] (peribronchiolar and perialveolar cuffing)
*Cause [[Peritoneal Cavity Inflammatory - Pathology#In sheep|peritonitis in sheep]], [[Peritoneal Cavity Inflammatory - Pathology#In goats|peritonitis in goats]] and [[Peritoneal Cavity Inflammatory - Pathology#In pigs|peritonitis in pigs]]
[[Category:Infectious_Agents]]