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[[Neospora]]
 
[[Neospora]]
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==Sarcocystis==
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[[Sarcocystis]]
[[Image:Sarcocystis Life Cycle.jpg|thumb|right|150px|''Sarcocytis'' Life Cycle Diagram - Dennis Jacobs & Mark Fox RVC]]
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[[Image:Sarcocystic.jpg|thumb|right|150px|''Sarcocytis'' - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]
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[[Image:Sarcocystis in sheep oesophagus.jpg|thumb|right|150px|''Sarcocystis'' in sheep oesophagus - Adam Cuerden]]
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[[Image:Equine protozoal myeloencephalitis.jpg|thumb|right|150px|Equine protozoal myeloencephalitis - Wikimedia Commons]]
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[[Image:Sarcocystis cruzi.jpg|thumb|right|150px|''Sarcocystis cruzi'' - Courtesy of the Laboratory of Parasitology, University of Pennsylvania School of Veterinary Medicine]]
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*Most infections are asymptomatic
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*Heavy infections are causes of chronic wasting in large animals, hide condemnation and downgrading of carcasses
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*''Sarcocystis'' should be differentiated from other tissue-cyst forming coccidia
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*There are many species of ''Sarcocystis'' which differ in size from microscopic to several centimetres in length
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**''S.neurona'' is an important equine pathogen in the USA
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*Infective cyst in the intermediate host is called a '''sarcocyst'''
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'''Life Cycle'''
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*The individual life cycle of some species is incompletely understood
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*Indirect life cycle
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*Life cycle alternates between the final and the obligatory intermediate host
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*Only '''one''' final and '''one''' intermediate host
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*Sporulated oocyst has 2 sporocysts containing 4 sporozoites
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**Naked sporocyst usually seen in faeces as the oocyst wall is very delicate
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**Oocyst measures 15μm in length
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*No schizogony in final host
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*Gametogeny occurs deep in subepithelial tissue
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*Faecal oocyst count is low
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*Oocysts are sporulated when passed
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**Difficult to find on faecal examination as the sporocysts are few in number and small
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*Ingestion of sporocyst by intermediate host
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**2 phases of rapid asexual reproduction in vascular endothelial cells
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**Slow multiplication of bradyzoites in muscle tissue
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**Sarcocyst forms with bradyzoites inside, surrounded by a cyst wall and divided into compartments
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'''Epidemiology'''
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*Final hosts are carnivores and omnivores
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*Intermediate hosts are herbivores and omnivores
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*Humans are the final host for some species and the intermediate hosts for others
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**Final host for species infecting cattle and pigs
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*Dogs are final hosts for species infecting cattle, sheep, goats, pigs and horses
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*Cats are final hosts for species infecting cattle, sheep and pigs
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'''Pathogenesis'''
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*Widespread infection but mostly asymptomatic
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*Cause meat inspection losses
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*''Sarcocystis'' in [[Muscles Inflammatory - Pathology#Protozoa|myositis]]
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*Experimental infections cause severe, acute pyrexic disease when the organism multiplies in the vascular endothelium
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*Can cause chronic wasting disease in cattle and horses
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**Causes abortion and post-natal disease in sheep
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*Equine protozoal myeloencephalitis
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**Necrotising encephalomyelitis affecting the grey and white matter of the CNS
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**Caused by ''S.neurona''
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**Opossum thought to be the definitive host
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**Horses thought to be accidental hosts
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**Natural intermediate hosts currently unknown
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**Western Blotting shows 50% of horses in the USA are seropositive
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**Risk factors poorly understood
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**Causes spinal cord dysfunction
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***Ataxia and paralysis
      
==Toxoplasma==
 
==Toxoplasma==
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==[[Protozoa Flashcards - Wikibugs#Tissue Cyst Forming Coccidia|Tissue Cyst Forming Coccidia Flashcards]]==
 
==[[Protozoa Flashcards - Wikibugs#Tissue Cyst Forming Coccidia|Tissue Cyst Forming Coccidia Flashcards]]==
[[Category:Piroplasmida]]
 
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