Author, Donkey, Bureaucrats, Administrators
53,803
edits
Changes
Hydatid Cysts - Donkey (view source)
Revision as of 12:57, 13 February 2010
, 12:57, 13 February 2010no edit summary
|linkpage =Lower Respiratory Tract Disorders - Donkey
|linkpage =Lower Respiratory Tract Disorders - Donkey
|linktext =Lower Respiratory Tract Disorders - Donkey
|linktext =Lower Respiratory Tract Disorders - Donkey
|sublink1 = Endoparasites - Donkey
|subtext1 = Endoparasites - Donkey
|rspace={{Donkey}}
|rspace={{Donkey}}
|pagetype=Donkey
|pagetype=Donkey
=Hydatid cysts - ''Echinococcus granulosus equinus''=
==Introduction==
[[Image:Hydatid cyst donkey.jpg|right|thumb|250px|<small><center>Hydatid cyst in the liver of a donkey (Image courtesy of [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]]
Hydatid cysts and the chronic remnants of these are frequently found at ''post-mortems'' carried out at [http://drupal.thedonkeysanctuary.org.uk/ The Donkey Sanctuary]. 7.8% of livers examined had a lesion indicative of a hydatid cyst. A higher incidence of hydatid cysts has been found in donkeys admitted from Ireland and Wales. In the UK, endemic areas for ''E. granulosus'' are mainly confined to the Powys area of
Wales and the Outer Hebrides in Scotland. In parts of the tropics, where dogs have access to carcasses, the prevalence can be particularly high.
Hydatid cysts are the intermediate larval stage (metacestode) of the [[Echinococcus|canine tapeworm]], ''Echinococcus granulosus'', which has dogs and foxes as the final host. Donkeys and horses are generally infected with the strain ''Echinococcus granulosus equinus'', which has different host predilections from the strains that are adapted to ruminants and man. The donkey and horse act as intermediate hosts in which hydatid cysts form.
==Aetiology==
Donkeys ingest the eggs of ''E. granulosus'' from pastures or feed contaminated with canine faeces. Ingested tapeworm eggs migrate from the donkey’s intestine to the liver, lung and, to a lesser extent, to other organs where they form cysts and grow slowly reaching up to 6 or 7 cm diameter.
==Diagnosis==
===Clinical signs===
Most cysts are asymptomatic and are found as incidental findings at ''post-mortem''. However, in large numbers, cysts can affect organ function. Clinical signs depend on the location of the cyst, severity of infection and size of the cyst, and are related to '''dysfunction of the liver'''.
===Laboratory tests===
* It is often not detected until ''post-mortem''.
* Immunodiagnostic tests are possible, though not commonly used for diagnosis ''ante-mortem''.
===Ultrasonography===
The cysts can be visualised using ultrasonography.
==Treatment==
Drainage of cysts can seed daughter cysts and induce anaphylaxis, although success has been reported in treating a horse with an
isolated retrobulbar cyst (Summerhayes and Mantell, 1995).
==Control==
* Centred on eliminating the tapeworm in the final host, e.g. dogs, by regular use of a suitable dewormer such as [[Praziquantel|praziquantel]] in endemic areas
* Dogs should be prevented from eating raw offal
* Preventing dogs and foxes from ingesting carcasses, which may harbour the cysts
** Under the Animal By-Products Order 1999, carcasses should be buried in such a way that carnivorous animals cannot gain access to them
* Prevention of faecal contamination of donkey pastures by dogs and/or their faeces should be removed from pastures
==References==
* Thiemann, A. (2008) Respiratory problems In Svendsen, E.D., Duncan, J. and Hadrill, D. (2008) ''The Professional Handbook of the Donkey'', 4th edition, Whittet Books, Chapter 7
* Trawford, A. and Getachew, M. (2008) Parasites In Svendsen, E.D., Duncan, J. and Hadrill, D. (2008) ''The Professional Handbook of the Donkey'', 4th edition, Whittet Books, Chapter 6
* Summerhayes, G.E.S., Mantell, J.A.R. (1995). ‘Ultrasonography as an aid to diagnosis and treatment of a retrolobular hydatid cyst in a horse’. ''Equine Veterinary Education'', 7(1). pp 39-42.
==References==
==References==
* Thiemann, A. (2008) Respiratory problems In Svendsen, E.D., Duncan, J. and Hadrill, D. (2008) ''The Professional Handbook of the Donkey'', 4th edition, Whittet Books, Chapter 7
* Thiemann, A. (2008) Respiratory problems In Svendsen, E.D., Duncan, J. and Hadrill, D. (2008) ''The Professional Handbook of the Donkey'', 4th edition, Whittet Books, Chapter 7