Difference between revisions of "Melophagus ovinus"

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{{OpenPagesTop}}
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*Also known as sheep ked
{{Taxobox
 
|name              =Melophagus spp
 
|kingdom            =Animalia
 
|phylum            =[[:Category:Arthropods|Arthropoda]]
 
|class              =[[Insecta]]
 
|sub-class          =
 
|order              =Diptera
 
|super-family      =
 
|family            =[[Hippoboscidae]]
 
|sub-family        =
 
|genus              =Melophagus
 
|species            ='''''M. ovinus'''''
 
}}
 
Also known as: '''''Sheep Ked - Louse Fly'''''
 
  
== Introduction==
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*Found worldwide
  
Melophagus ovis is a wingless fly, also known as the sheep ked or 'louse fly', which parasitises the skin of sheep. It is similar to a louse as its' whole life cycle occurs on the host.
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*Bites sheep and goats
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**A separate species is found on deer
  
Melophagus is the intermediate host for the non-pathogenic ''Trypanosoma melophagium'' in sheep.
 
  
The fly often lives on sheep without any clinical signs, but in severe infestations, clinical signs will ensue. The disease manifests most commonly in autumn and winter. The parasite is found in the superficial layers of the fleece and this aids transmission to other sheep by direct contact. Long wooled breeds are most susceptible to infection.
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'''Recognition'''
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*4-6mm long
  
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*Hairy
  
==Identification==
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*Forward pointing proboscis
The adults are hairy, brown and around 6mm in length, and of the family [[Hippoboscidae]].  They have an segmented abdomen, and are wingless.  ''M. ovinus'' has blood sucking mouthparts, and claws on the ends of the legs, designed to hold on to the host.  They are dorso-ventrally flattened.
 
  
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*Short head
  
==Life Cycle==
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*Reddish brown colouring
They are permanent ectoparasites, feeding on the host. The female fly produce a single larvae at a time, and the larvae are held back until they are ready to pupate. The larvae undergo three larval stages before becoming fully developed. Pupation of the larvae occurs, and they are clearly seen on the fleeces of the sheep. These then later emerge as adults.
 
  
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*Dorso-ventrally flattened
  
== Clinical signs ==
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*'Tick-like' in appearance
  
The sheep may appear generally off colour. There will be noticeable wool damage and this will be due to self-trauma through itching. The fleece will also appear stained by the faeces of the sheep ked. On physical examination, anaemia may also be noted if the parasite burden is big enough.
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*'''Wingless'''
  
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*Strong legs and claws
  
== Diagnosis ==
 
  
By clinical signs and detection of the parasite on the sheep. Microscopic examination will determine the presence on ''Melophagus''.
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'''Life cycle'''
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*Whole life cycle spent '''on''' the host
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**Adults may survive for 1 week off the host
  
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*Single larvae laid on fleece which pupate
  
== Treatment and Control ==
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*Adult keds emerge a '''few weeks to a few months''' after pupating depending on environmental temperature
  
Treatment upon clinical signs and diagnosis, with a suitable ectoparasiticide.
 
  
Control measures include sheep dipping and spraying and shearing to decrease numbervsof the ked.
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'''Pathogenesis'''
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*Most numerous in '''autumn and winter'''
  
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*Located in the superficial layers of the fleece
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**This aids transmission
  
{{Learning
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*Long wooled breeds are most susceptible to infection
|literature search = [http://www.cabdirect.org/search.html?q=title%3A%28%22Melophagus+ovinus%22%29+OR+title%3A%28%22Sheep+Ked%22%29 ''Melophagus'' publications]
 
}}
 
  
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*Cause anaemia
  
{{review}}
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*Wool damage
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**Irritation and self-inflicted damage
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**Staining by ked faeces
  
{{OpenPages}}
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*Intermediate host for non-pathogenic ''Trypanosoma melophagium'' in sheep
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'''Control'''
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*Sheep dipping and spraying
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*Shearing to decrease numbers
  
 
[[Category:Hippoboscidae]]
 
[[Category:Hippoboscidae]]
[[Category:Dermatological Diseases - Sheep]]
 
[[Category:Integumentary System - Parasitic Infections]]
 
[[Category:Expert Review - Farm Animal]]
 

Revision as of 12:38, 5 April 2010

  • Also known as sheep ked
  • Found worldwide
  • Bites sheep and goats
    • A separate species is found on deer


Recognition

  • 4-6mm long
  • Hairy
  • Forward pointing proboscis
  • Short head
  • Reddish brown colouring
  • Dorso-ventrally flattened
  • 'Tick-like' in appearance
  • Wingless
  • Strong legs and claws


Life cycle

  • Whole life cycle spent on the host
    • Adults may survive for 1 week off the host
  • Single larvae laid on fleece which pupate
  • Adult keds emerge a few weeks to a few months after pupating depending on environmental temperature


Pathogenesis

  • Most numerous in autumn and winter
  • Located in the superficial layers of the fleece
    • This aids transmission
  • Long wooled breeds are most susceptible to infection
  • Cause anaemia
  • Wool damage
    • Irritation and self-inflicted damage
    • Staining by ked faeces
  • Intermediate host for non-pathogenic Trypanosoma melophagium in sheep


Control

  • Sheep dipping and spraying
  • Shearing to decrease numbers