Sarcocystis - Revision history

Bara at 23:01, 5 March 2011

2011-03-05T23:01:54Z

Bara at 18:25, 3 March 2011

2011-03-03T18:25:35Z

Eca02csb at 16:33, 20 August 2010

2010-08-20T16:33:01Z

Eca02csb at 10:12, 22 July 2010

2010-07-22T10:12:02Z

Bara at 10:50, 1 July 2010

2010-07-01T10:50:21Z

Bara at 22:20, 26 June 2010

2010-06-26T22:20:33Z

Bara at 23:00, 9 April 2010

2010-04-09T23:00:27Z

Bara: Created page with '''Sarcocytis'' Life Cycle Diagram - Dennis Jacobs & Mark Fox RVC [[Image:Sarcocystic.jpg|thumb|right|150px|''Sarcocytis'' -…'

2010-04-09T22:59:31Z

New page

[[Image:Sarcocystis Life Cycle.jpg|thumb|right|150px|''Sarcocytis'' Life Cycle Diagram - Dennis Jacobs & Mark Fox RVC]]
[[Image:Sarcocystic.jpg|thumb|right|150px|''Sarcocytis'' - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]
[[Image:Sarcocystis in sheep oesophagus.jpg|thumb|right|150px|''Sarcocystis'' in sheep oesophagus - Adam Cuerden]]
[[Image:Equine protozoal myeloencephalitis.jpg|thumb|right|150px|Equine protozoal myeloencephalitis - Wikimedia Commons]]
[[Image:Sarcocystis cruzi.jpg|thumb|right|150px|''Sarcocystis cruzi'' - Courtesy of the Laboratory of Parasitology, University of Pennsylvania School of Veterinary Medicine]]
*Most infections are asymptomatic

*Heavy infections are causes of chronic wasting in large animals, hide condemnation and downgrading of carcasses

*''Sarcocystis'' should be differentiated from other tissue-cyst forming coccidia

*There are many species of ''Sarcocystis'' which differ in size from microscopic to several centimetres in length
**''S.neurona'' is an important equine pathogen in the USA

*Infective cyst in the intermediate host is called a '''sarcocyst'''

'''Life Cycle'''
*The individual life cycle of some species is incompletely understood

*Indirect life cycle

*Life cycle alternates between the final and the obligatory intermediate host

*Only '''one''' final and '''one''' intermediate host

*Sporulated oocyst has 2 sporocysts containing 4 sporozoites
**Naked sporocyst usually seen in faeces as the oocyst wall is very delicate
**Oocyst measures 15μm in length

*No schizogony in final host

*Gametogeny occurs deep in subepithelial tissue

*Faecal oocyst count is low

*Oocysts are sporulated when passed
**Difficult to find on faecal examination as the sporocysts are few in number and small

*Ingestion of sporocyst by intermediate host
**2 phases of rapid asexual reproduction in vascular endothelial cells
**Slow multiplication of bradyzoites in muscle tissue
**Sarcocyst forms with bradyzoites inside, surrounded by a cyst wall and divided into compartments

'''Epidemiology'''
*Final hosts are carnivores and omnivores

*Intermediate hosts are herbivores and omnivores

*Humans are the final host for some species and the intermediate hosts for others
**Final host for species infecting cattle and pigs

*Dogs are final hosts for species infecting cattle, sheep, goats, pigs and horses

*Cats are final hosts for species infecting cattle, sheep and pigs

'''Pathogenesis'''
*Widespread infection but mostly asymptomatic

*Cause meat inspection losses

*''Sarcocystis'' in [[Muscles Inflammatory - Pathology#Protozoa|myositis]]

*Experimental infections cause severe, acute pyrexic disease when the organism multiplies in the vascular endothelium

*Can cause chronic wasting disease in cattle and horses
**Causes abortion and post-natal disease in sheep

*Equine protozoal myeloencephalitis
**Necrotising encephalomyelitis affecting the grey and white matter of the CNS
**Caused by ''S.neurona''
**Opossum thought to be the definitive host
**Horses thought to be accidental hosts
**Natural intermediate hosts currently unknown
**Western Blotting shows 50% of horses in the USA are seropositive
**Risk factors poorly understood
**Causes spinal cord dysfunction
***Ataxia and paralysis[[Category:Tissue_Cyst_Forming_Coccidia]]

@@ Line 71: / Line 71: @@
 [[Image:Sarcocyst in muscle.jpg|right|thumb|100px|<small><center>Sarcocyst (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]]
 **Histologically:
-***Merozoites causing focal and segmental [[Muscles Degenerative - Pathology#Necrosis|necrosis]]
+***Merozoites causing focal and segmental [[Muscle Necrosis|necrosis]]
-***May involve [[Muscles Degenerative - Pathology#Calcification|mineralisation]]
+***May involve [[Muscle Calcification|mineralisation]]
 ***Non-purulent myositis with plasma cells, lymphocytes and macrophages
 **Diaphragm and masseters most severely affected

@@ Line 75: / Line 75: @@
 ***Non-purulent myositis with plasma cells, lymphocytes and macrophages
 **Diaphragm and masseters most severely affected
 [[Category:Tissue_Cyst_Forming_Coccidia]]
 [[Category:To_Do_-_Parasites]]

@@ Line 68: / Line 68: @@
 *[[Equine Protozoal Myeloencephalitis]]
+*Myositis
 [[Category:Tissue_Cyst_Forming_Coccidia]]
 [[Category:To_Do_-_Parasites]]

← Older revision		Revision as of 22:20, 26 June 2010
Line 70:		Line 70:

	[[Category:Tissue_Cyst_Forming_Coccidia]]		[[Category:Tissue_Cyst_Forming_Coccidia]]
		+
		+	[[Category:To_Do_-_Parasites]]

@@ Line 59: / Line 59: @@
 *Cause meat inspection losses
-*''Sarcocystis'' in [[Muscles Inflammatory - Pathology#Protozoa|myositis]]
+*''Sarcocystis'' in [[Parasitic Myositis#Protozoa|myositis]]
 *Experimental infections cause severe, acute pyrexic disease when the organism multiplies in the vascular endothelium

@@ Line 1: / Line 1: @@
 [[Image:Sarcocystis Life Cycle.jpg|thumb|right|150px|''Sarcocytis'' Life Cycle Diagram - Dennis Jacobs & Mark Fox RVC]]
 [[Image:Sarcocystic.jpg|thumb|right|150px|''Sarcocytis'' - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]
-[[Image:Sarcocystis in sheep oesophagus.jpg|thumb|right|150px|''Sarcocystis'' in sheep oesophagus - Adam Cuerden]]
+[[Image:Sarcocystis in sheep oesophagus.jpg|thumb|right|150px|''Sarcocystis in sheep oesophagus'' <br> Adam Cuerden, Wikimedia Commons]]
 [[Image:Equine protozoal myeloencephalitis.jpg|thumb|right|150px|Equine protozoal myeloencephalitis - Wikimedia Commons]]
 [[Image:Sarcocystis cruzi.jpg|thumb|right|150px|''Sarcocystis cruzi'' - Courtesy of the Laboratory of Parasitology, University of Pennsylvania School of Veterinary Medicine]]

@@ Line 66: / Line 66: @@
 **Causes abortion and post-natal disease in sheep
-*Equine protozoal myeloencephalitis
+*[[Equine Protozoal Myeloencephalitis]]
-**Necrotising encephalomyelitis affecting the grey and white matter of the CNS
-**Caused by ''S.neurona''
-**Opossum thought to be the definitive host
+[[Category:Tissue_Cyst_Forming_Coccidia]]