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−|linkpage =Insecta
−|linktext =INSECTA
−|pagetype=Bugs
−|sublink1=Parasites
−|subtext1=PARASITES
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−==Phthiraptera Introduction==
−[[Image:Arthropod classifiation.jpg|thumb|right|150px|Arthropod Classification - copyright nabrown RVC]]
−Lice are obligate ectoparasites of every avian and most mammalian species. They are only a few millimeters long and like [[Fleas - WikiBlood|fleas]], are wingless but unlike [[Fleas - WikiBlood|fleas]] are dorsoventrally flattened.
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−Lice are host specific, permanent parasites which cause 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==
−''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==
−''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
−**It can however survive for one week off the animal
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−*In some species 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==
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−*Pediculosis is an infestation of lice
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−*Pediculosis in farm animals is most often seen in winter when the coat is thickest
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−*Debilitated animals are often lousy as they cannot groom properly
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−===Cattle===
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−*One chewing louse
−**''Bovicola bovis''
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−*Several sucking lice
−**E.g. ''Linognathus vituli''
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−*Most lice have a preferred predilection site on the body
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−*Some lice will gather in clusters
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−*Causes ill-thrift, anaemia and can lead to down-graded leather
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−===Sheep===
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−*One chewing louse
−**''Damalinia ovis''
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−*Two sucking lice
−**''Lignognathus'' spp.
−***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
−**''Haematopinus suis''
−**Large 5mm louse which is easily visible on the skin
−**Vector of African swine fever virus and rickettsiae
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−===Horses===
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−*One chewing louse
−**''Damalinia equi''
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−*One sucking louse
−**''Haematopinus asini''
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−*Mainly in the mane and tail but can spread over the body
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−===Dogs===
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−*One chewing louse
−**''Trichodectes''
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−*One sucking louse
−**''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
−**''Felicola''
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−===Poultry===
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−*Several species of chewing lice
−**''Lipeurus'' spp. are the most pathogenic
−***E.g. the 'wing louse' and the 'head louse'
−**''Menacanthis'' spp. are also pathogenic
−***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
−**At two week intervals
−**Or a product with a two week residual activity can be used
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−Anoplura lice are more susceptible to systemic insecticide treatment than mallophaga 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]]==
#REDIRECT[[:Category:Lice]]
−[[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]]
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