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42 bytes added ,  21:57, 21 December 2008
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**the eggs are single (i.e. not in packets like Dipylidium)
 
**the eggs are single (i.e. not in packets like Dipylidium)
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T. ovis
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1) '''''T. ovis'''''
Cysticerci occur in the musculature of sheep = condemnation of meat on aesthetic grounds.
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*Cysticerci occur in the musculature of sheep = condemnation of meat on aesthetic grounds.
Common in some sheep-raising areas of the UK.
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*Common in some sheep-raising areas of the UK.
Known as ‘sheep measles’ in Australasia, where it causes economic loss to the export industry.
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*Known as ‘sheep measles’ in Australasia, where it causes economic loss to the export industry.
Consequently, a recombinant oncosphere antigen vaccine is available in New Zealand.
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*Consequently, a recombinant oncosphere antigen vaccine is available in New Zealand.
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T. hydatigena
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2) '''''T. hydatigena'''''
The commonest species in the UK.
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*The commonest species in the UK.
Sheep are the most frequent intermediate host, but the cysticerci can establish in other animals.
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*Sheep are the most frequent intermediate host, but the cysticerci can establish in other animals.
The oncosphere hatches out of the egg in the small intestine of the sheep.
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*The oncosphere hatches out of the egg in the small intestine of the sheep.
Oncospheres travel to the hepatic portal system, where they transform to cysticerci.
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*Oncospheres travel to the hepatic portal system, where they transform to cysticerci.
The grow rapidly while migrating through liver parenchyma, then to the peritoneal cavity.
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*The grow rapidly while migrating through liver parenchyma, then to the peritoneal cavity.
The cysticerci in the peritoneal cavity are approximately 8cm long; often found adhering to the omentum.
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*The cysticerci in the peritoneal cavity are approximately 8cm long; often found adhering to the omentum.
Usually, liver damage heals, forming fibrotic tracts, which leads to condemnation at meat inspection.
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*Usually, liver damage heals, forming fibrotic tracts, which leads to condemnation at meat inspection.
If a sheep swallows a whole proglottid, it leads to liver damage, and ultimately death (“cysticercosis hepatica”), but this is a rare event affecting a single animal in a flock.
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*If a sheep swallows a whole proglottid, it leads to liver damage, and ultimately death (“cysticercosis hepatica”), but this is a rare event affecting a single animal in a flock.
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T. pisiformis
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3) '''''T. pisiformis'''''
It is similar to T. hydatigena, except that the cysticerci are pea-sized and are found on the omentum of rabbits.
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*It is similar to T. hydatigena, except that the cysticerci are pea-sized and are found on the omentum of rabbits.
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T. multiceps (also known as Multiceps multiceps)
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4) '''''T. multiceps''''' (also known as Multiceps multiceps)
Widespread distribution in the UK; particularly common in parts of mid-Wales.
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*Widespread distribution in the UK; particularly common in parts of mid-Wales.
The eggs hatch in the small intestine of the sheep.
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*The eggs hatch in the small intestine of the sheep.
The oncosphere enters the blood stream and travels to the brain, where it migrates through brain tissue.
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*The oncosphere enters the blood stream and travels to the brain, where it migrates through brain tissue.
The metacestode (a coenurus) occurs inside the skull, lying on the surface of the brain.
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*The metacestode (a coenurus) occurs inside the skull, lying on the surface of the brain.
It forms a 5cm long space occupying lesion.
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*It forms a 5cm long space occupying lesion.
This leads to neurological signs, including gid – circling, ataxia and blindness.
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*This leads to neurological signs, including gid – circling, ataxia and blindness.
It also causes softening of the skull above the lesion.
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*It also causes softening of the skull above the lesion.
If a whole proglottid is ingested, it can lead to acute encephalitis (very rare).
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*If a whole proglottid is ingested, it can lead to acute encephalitis (very rare).
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T. serialis
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5) '''''T. serialis'''''
The coenurus forms in intermuscular connective tissues of rabbits, often causing a soft subdermal swelling.  
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*The coenurus forms in intermuscular connective tissues of rabbits, often causing a soft subdermal swelling.  
Cases in pet rabbits probably originate from eggs shed by urban foxes.
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*Cases in pet rabbits probably originate from eggs shed by urban foxes.
     
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