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| Line 23: |
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| | *2 nymphal stages | | *2 nymphal stages |
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| | + | <big> |
| | + | '''[[Psoroptes cuniculi|''Psoroptes cuniculi'']] |
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| − | [[Psoroptes cuniculi|''Psoroptes cuniculi'']] | + | '''[[Psoroptes ovis|''Psoroptes ovis'']] |
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| − | | + | </big> |
| − | | |
| − | ====''Psoroptes ovis''====
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| − | | |
| − | *Adult females are large mites at 750μm in length
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| − | | |
| − | *Males identified by copulatory suckers and paired posterior lobes
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| − | | |
| − | *Males attach to deutonymphs (second moult after larval stage) in a process called '''copula'''
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| − | **Males remain in copula until females moult for the last time
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| − | **Copulation occurs
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| − | | |
| − | *Life cycle last '''14 days'''
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| − | | |
| − | *Transmitted by direct contact between sheep
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| − | | |
| − | *Indirect transmission can also occur
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| − | | |
| − | | |
| − | '''Pathogenesis'''
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| − | *Economically important ectoparasite of sheep
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| − | | |
| − | *Causes '''sheep scab'''
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| − | **Wool loss, restlessness, biting, scratching of infested area and decreased productivity through decreased weight gain
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| − | **Usually seen in '''late autumn''' and '''early winter''' (although may also occur in late summer)
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| − | **Population numbers decline after shearing due to a change in the micro-climate, then build up again as the fleece grows
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| − | **'''Notifiable in UK'''
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| − | | |
| − | *Mites found under scabs and in skin folds
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| − | | |
| − | *Lesions most common on flanks, neck, back and shoulders
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| − | | |
| − | *Causes pruritic condition of cattle
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| − | | |
| − | *Active in keratin layer
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| − | | |
| − | *Mouthparts abrade the skin
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| − | | |
| − | *Antigenic material in mite faeces can lead to hypersensitivity reactions
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| − | | |
| − | | |
| − | '''Diagnosis'''
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| − | *Skin scraping
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| − | | |
| − | *KOH added
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| − | | |
| − | *Warm slide over a bunsen flame
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| − | | |
| − | *Examine under a microscope
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| − | | |
| − | | |
| − | '''Treatment'''
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| − | *Sheep
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| − | **Plunge dipping; no less than 1 minute and must dip head at lease once
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| − | **Can treat with avermectins or milbemycins by injection
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| − | | |
| − | *Cattle, horses and rabbits
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| − | **No licensed product for horses in the UK
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| − | **Cattle and rabbits can be treated with avermectins, milbemycins or topical acaricides
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| | [[Category:Non-Burrowing Mites]] | | [[Category:Non-Burrowing Mites]] |