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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]] | |
| − | 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==
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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]]
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| − | ''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 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
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| − | **''Bovicola bovis''
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| − | *Several sucking lice
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| − | **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
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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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| − | **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 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''
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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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| − | ***E.g. the 'wing louse' and the 'head louse'
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| − | **''Menacanthis'' 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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| − | Anopleura 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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