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− | {{review}}
| + | #REDIRECT[[:Category:Lice]] |
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− | {{toplink
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− | |backcolour =
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− | |linkpage =Insecta
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− | |linktext =INSECTA
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− | |pagetype=Bugs
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− | |sublink1=Parasites
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− | |subtext1=PARASITES
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− | }}
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− | <br>
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− | ==Phthiraptera introduction==
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− | [[Image:Arthropod classifiation.jpg|thumb|right|150px|Arthropod Classification - copyright nabrown RVC]]
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− | Lice are obligate ectoparasites of every avian and most mammalian species. They are only a few millimeters long and like [[Fleas|fleas]], are wingless but unlike [[Fleas|fleas]] are dorsoventrally flattened.
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− | Lice are host specific, permanent parasites which cause [[Parasitic skin infections - Pathology#Lice|pediculosis]]. The louse saliva and faeces contain allergenic substances which cause irritation, rubbing, licking and skin damage leading to decreased host productivity.
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− | Mammalian lice species have a single pair of claws on the ends of stout legs, whereas avian lice species have a double claw on each leg.
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− | There are two main groups of veterinary importance, the mallophaga (chewing lice) and anoplura (sucking lice).
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− | ==Mallophaga==
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− | ''Also known as '''chewing lice''' or '''biting lice''' ''
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− | *Broad head
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− | *Thorax narrower than the head
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− | *Rasping mouthparts
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− | *Feeds on epithelial scales, scabs, feathers and other bodily debris
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− | *Species occur on both mammals and birds
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− | ==Anoplura==
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− | [[Image:Sucking Louse.jpg|thumb|right|150px|Sucking Louse ''Pediculosis humanus'' - From: Genetic Analysis of Lice Supports Direct Contact between Modern and Archaic Humans Reed DL, Smith VS, Hammond SL, Rogers AR, Clayton DH PLoS Biology Vol. 2, No. 11, e340 doi:10.1371/journal.pbio.0020340]] | |
− | ''Also known as '''sucking lice''' ''
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− | *Narrow head
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− | *Thorax wider than the head
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− | *Powerful legs
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− | *Piercing mouthparts
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− | *Feed on blood and tissue fluids
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− | *Heavy infestations can cause anaemia
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− | *Species occur only on mammals
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− | ==Life cycle==
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− | *The whole life cycle takes '''2-3 weeks'''
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− | *The louse spends its whole life on the animal
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− | **It can however survive for one week off the animal
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− | *In some species [[WikiWords#P|parthenogenesis]] can occur
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− | *Close contact transmission can occur
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− | '''1. Eggs'''
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− | *Known as nits
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− | *Cemented to hairs
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− | '''2. Nymphs'''
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− | *Nymphs hatch from the egg (no larval stage)
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− | *Undergoes several moults
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− | '''3. Adults'''
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− | *Females can lay up to '''10 eggs per day'''
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− | *Pediculosis is an infestation of lice
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− | <big>'''[[Pediculosis - Cattle]]
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− | ==Pediculosis==
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− | ===Sheep===
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− | *One chewing louse
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− | **''Damalinia ovis''
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− | *Two sucking lice
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− | **''Lignognathus spp.''
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− | ***The 'foot louse' and the 'face louse'
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− | *Causes fleece damage
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− | ===Pigs===
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− | *One sucking louse
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− | **''Haematopinus suis''
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− | **Large 5mm louse which is easily visible on the skin
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− | **Common to the UK
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− | **Overseas it is a vector of African swine fever virus and rickettsiae
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− | ===Horses===
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− | *One chewing louse
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− | **''Damalinia equi''
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− | *One sucking louse
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− | **''Haematopinus asini''
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− | *Mainly found in the mane and tail but can spread over the body
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− | ===Dogs===
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− | *One chewing louse
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− | **''Trichodectes canis''
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− | *One sucking louse
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− | **''Linognathus setosus''
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− | *Neglect is usually associated with heavy infestations
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− | ===Cats===
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− | *One chewing louse
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− | **''Felicola''
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− | ===Poultry===
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− | *Several species of chewing lice
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− | **''Lipeurus spp.'' are the most pathogenic
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− | ***The 'wing louse' and the 'head louse'
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− | **''Menacanthus spp.'' are also pathogenic
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− | ***Lays its eggs in clusters around the [[The Avian Vent and Cloaca - Anatomy & Physiology|cloaca]]
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− | *No sucking lice
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− | ==Control==
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− | *Few insecticides will kill lice eggs on the animal
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− | *'''Two treatments''' are needed to kill nymphs emerging from eggs at the time of the initial treatment and those that will emerge 2-3 weeks later
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− | **At '''two week intervals'''
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− | **Or a product with a '''two week residual activity''' can be used
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− | *Sucking lice are more susceptible to systemic insecticide treatment than chewing lice
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− | *Resistance to insecticides may become a problem so alternating the chemicals used and avoiding pour on treatments (which have a greater risk of resistance developing) should be considered
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− | ==[[Insecta Flashcards - WikiBugs#Lice|Lice Flashcards]]==
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− | [[Category:Parasites]]
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