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1,393 bytes added ,  20:17, 9 November 2008
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'''Epidemiology'''
 
'''Epidemiology'''
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*Divided into categories depending on their ability to initiate strike
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**Primary flies are capable of initiating a strike on living sheep so larvae can penetrate intact skin
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***E.g. ''Lucilla'', ''Phormia'' and ''Calliphora''
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**Secondary flies cannot initiate a strike, larvae attack an area already struck or damaged, extending it
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***E.g. ''Callipohora'' and ''Chrysoma'' (in warmer climates)
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**Tertiary flies attack lesions on carcasses which have become dry
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***E.g. ''Musca'' and ''Sarcophaga'' spp.
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*Temperature will affect the prevalence of strike
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**Temperature in the spring will determine when the overwintering larvae hatch
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**High temperature and humidity will create a microclimate in the fleece, attracting adult flies to lay eggs
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*Persistent rainfall will make the fleece microclimate attractive to adult flies
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**Females lay eggs after the rain ceases
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**Breeds with long, fine wool are the most susceptible
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*Host susceptibility is increased when putrefactive odours develop on the fleece due to bacterial decomposition of organic matter
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**Merino sheep have a narrow breach area with excessive wrinkling making them more suceptible to soiling
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**A narrow opening of the penile sheath in rams and wethers may result in accumulation of urine and increase blowfly strike in this area
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**Cuts during shearing, fighting and barbed wire will also increase the incidence of blowfly strike
    
'''Pathogenesis'''
 
'''Pathogenesis'''
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