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69 bytes removed ,  11:34, 19 August 2010
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==Treatment==
 
==Treatment==
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The best method of controlling ovine toxoplasmosis is by prevention. A live vaccine containing tachyzoites of the avirulent S48 strain is available. These tachyzoites do not cause pathology or form bradyzoites or tissues cysts. A single dose of vaccine is administered intramuscularly at least 3 weeks (and up to four months) prior to mating, from an age of five months. The vaccine is known to protect agains toxoplasmosis for at least two lambing seasons, possible more.
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In the event of an outbreak, little can be done to prevent further spread since transmission is via contaminated food or water rather than sheep-to-sheep contact. Since environmental contamination is related to the behaviour of cats, numbers should be limited. Keeping an older, neutered male cat may help ward of other felines: since most cats seroconvert at a young age, adults are unlikely to shed oocysts to contribute to contamination. Rodents and other vermin transmit toxoplasmosis to cats, and so populations should also be controlled. Animals should be prevented from gaining access to feed or bedding.
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Previously, monensin has been given in sheep feed in the lead up to lambning. Although this was shown to reduce perinatal lamb mortality related to ''Toxoplasma'' infection, monensin is no longer licensed for sheep and should not be used.
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The best method of controlling ovine toxoplasmosis is therefore by vaccination. A live vaccine containing tachyzoites of the avirulent S48 strain is available. These tachyzoites do not cause pathology or form bradyzoites or tissues cysts. A single dose of vaccine is administered intramuscularly at least 3 weeks (and up to four months) prior to mating, from an age of five months. The vaccine is known to protect agains toxoplasmosis for at least two lambing seasons, possible more.
 
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**Medicated feed can be given daily during the main risk period
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***14 weeks before lambing
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**The best method of protection is to prevent cats from contaminating the pasture, lambing sheds and feed stores
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The extent of environmental
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contamination with T. gondii oocysts is thus
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related to the distribution and behaviour of cats.
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Measures to reduce environmental contamination
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by oocysts should be aimed at reducing the number
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of cats capable of shedding oocysts. This would include
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attempts to limit their breeding. If male cats are
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caught, neutered and returned to their colonies the
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stability ofthe colony is maintained; fertile male cats
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do not challenge the neutered males12 and breeding
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is controlled. Thus the maintenance ofa small healthy
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population of mature cats will reduce oocyst excretion
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as well as help to control rodents. Sheep feed should be
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kept covered at all times to prevent its contamination
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by cat faeces.
      
==Prognosis==
 
==Prognosis==
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