Difference between revisions of "Neospora"

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**In cattle, vertical transmission occurs
 
**In cattle, vertical transmission occurs
 
***Post-natal infection occurs but is less common
 
***Post-natal infection occurs but is less common
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*''Neospora caninum'' in [[Parasitic Myositis#Protozoa|myositis]]
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'''Pathogenesis'''
 
'''Pathogenesis'''
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<big>
 
<big>
 
'''[[Neosporosis - Dog|Dog Neosporosis]]
 
'''[[Neosporosis - Dog|Dog Neosporosis]]
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'''[[Neosporosis - Cattle|Cattle Neosporosis]]
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'''[[Neosporosis - Horse|Horse Neosporosis]]
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</big>
  
  
*Cattle
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*''N. caninum''
**Commonest cause of infectious abortion in dairy cattle
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**Necrotising inflammation of muscles
**Congenitally infected calves can have encephalomyelitis and paresis
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**Myositis more severe than in toxoplasmosis
**Abortion usually occurs between 5-7 months of gestation but can occur as early as 3 months
 
**No other clinical signs in the cow
 
**Repeat abortions possible in same cow (persistently infected)
 
'''Prevention and Control'''
 
*Do not allow dogs access to calving cows, placental membranes and aborted or dead calves
 
  
*Do not allow dogs to defecate in cattle feeding areas
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''N. caninum'' - A disease of cattle with late abortion of mummified or autolysed foetus. May also get foetal malformation, e.g. arthrogryposis.
  
*Identify and cull seropositive cattle, or do not breed from them or their progeny
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==Test yourself with the Tissue Cyst Forming Coccidian Flashcards==
  
*Select seronegative cattle for breeding
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[[Tissue_Cyst_Forming_Coccidian_Flashcards|Tissue Cyst Forming Coccidian Flashcards]]
  
*Vaccinate
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[[Category:Tissue Cyst Forming Coccidia]]
**Only in the USA
 
**Neoguard or Intervet
 
**Killed protozoal vaccine for healthy, pregnant cows
 
**Dosed in first 3 weeks of pregnancy and then every 3-4 weeks during gestation
 
**Revaccination with 2 doses during each subsequent pregnancy[[Category:Tissue Cyst Foming Coccidia]]
 
*Horses
 
**Myeloencephalitis
 
**Transplacental infection occurs
 
**Disease only diagnosed in USA
 
  
*''Neospora caninum'' in [[Muscles Inflammatory - Pathology#Protozoa|myositis]]
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[[Category:To_Do_-_Parasites]]

Latest revision as of 23:01, 5 March 2011

  • 2 main species
    • Neospora caninum in the dog
    • Neospora hughesi in the horse
  • Sporulated oocysts measuring just 10μm
  • Oocyst contains 2 sporocysts with 4 sporozoites
  • Route of transmission not fully understood
  • Often misdiagnosed as Toxoplasma gondii
    • Sarcocystis cysts have thicker walls
  • Infection diagnosed by IFAT, ELISA or PCR
    • Identification of lesions and organisms in tissue using immunohistochemical staining
    • Eliminate other causes of abortion first

Life cycle

  • Life cycle similar to Toxoplasma gondii
  • Limited range of warm-blooded intermediate hosts
    • Asexual reproduction occurs in intermediate host forming tissue cysts
  • Host range of sexual stage is unknown for N.caninum
    • Intermediate host for N.hughesi is the horse, but the definitive host is unknown
  • Final host
    • Dogs pass oocysts
    • Role not fully understood in pathogenesis
    • 5 day prepatent period
    • Other wild canids may also act as final definitive hosts
  • Intermediate host
    • Mostly cattle
    • Natural infection has been documented in other herbivores
  • Transmission
    • Transplacental infection occurs in all intermediate hosts and in the canine final host
      • Transplacental transmission can occur in successive pregnancies
    • In cattle, vertical transmission occurs
      • Post-natal infection occurs but is less common


Pathogenesis

Dog Neosporosis

Cattle Neosporosis

Horse Neosporosis


  • N. caninum
    • Necrotising inflammation of muscles
    • Myositis more severe than in toxoplasmosis

N. caninum - A disease of cattle with late abortion of mummified or autolysed foetus. May also get foetal malformation, e.g. arthrogryposis.

Test yourself with the Tissue Cyst Forming Coccidian Flashcards

Tissue Cyst Forming Coccidian Flashcards