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Caused by [[Psoroptes]]
Caused by [[Psoroptes]]
*Occurs in cattle, sheep, horses, goats, rabbits and other animals
*Occurs in cattle, sheep, horses, goats, rabbits and other animals
*Host-specific
*Host-specific
*[[Psoroptes cuniculi|''Psoroptes cuniculi'']] in ear canals of rabbits, horses, goats and sheep
*[[Psoroptes cuniculi|''Psoroptes cuniculi'']] in ear canals of rabbits, horses, goats and sheep
'''Pathogenesis'''
'''Pathogenesis'''
*The ears are painful and intensely pruritic
*The ears are painful and intensely pruritic
*Mites are grossly visible
*Mites are grossly visible
*Histologically, there is chronic erosive and proliferative eosinophilic dermatitis
*Histologically, there is chronic erosive and proliferative eosinophilic dermatitis
**The mites are non-burrowing and thus are found only in the exudate, not in the tissue
**The mites are non-burrowing and thus are found only in the exudate, not in the tissue
<br>'''Diagnosis'''
*Microscopic examination for mites (low magnification)
*Microscopic examination for mites (low magnification)
*Appearance
*Appearance
<br>'''Control'''
*Infestations are difficult to eliminate from a colony
*Infestations are difficult to eliminate from a colony
**Ivermectin is usually effective.
**Ivermectin is usually effective.
<br>
*[[Psoroptes|''P.equi'']] at base of mane, tail and forelock in horses
*[[Psoroptes|''P.equi'']] at base of mane, tail and forelock in horses
*[[Psoroptes ovis|''P.ovis'']] in sheep ('''sheep scab''')and cattle
*[[Psoroptes ovis|''P.ovis'']] in sheep ('''sheep scab''')and cattle
**Thickened skin and dry scales and crusts
**Thickened skin and dry scales and crusts
**Starts at withers and spreads due to self trauma
**Starts at withers and spreads due to self trauma
**Microscopically:
**Microscopically:
***Spongiotic, hyperplastic or exudative superficial perivascular dermatitis
***Spongiotic, hyperplastic or exudative superficial perivascular dermatitis
***Eosinophils[[Category:To_Do_-_Clinical]]
***Eosinophils
<br>
=== Pathogenesis ===
*Economically important ectoparasite of sheep
*Economically important ectoparasite of sheep
*Causes '''sheep scab'''
*Causes '''sheep scab'''
**Wool loss, restlessness, biting, scratching of infested area and decreased productivity through decreased weight gain
**Wool loss, restlessness, biting, scratching of infested area and decreased productivity through decreased weight gain
**Usually seen in '''late autumn''' and '''early winter''' (although may also occur in late summer)
**Usually seen in '''late autumn''' and '''early winter''' (although may also occur in late summer)
**Population numbers decline after shearing due to a change in the micro-climate, then build up again as the fleece grows
**Population numbers decline after shearing due to a change in the micro-climate, then build up again as the fleece grows
**'''Notifiable in UK'''
**'''Notifiable in UK'''
*Antigenic material in mite faeces can lead to hypersensitivity reactions
*Antigenic material in mite faeces can lead to hypersensitivity reactions
===Diagnosis===
=== Diagnosis ===
*Skin scraping
*Skin scraping
*Examine under a microscope
*Examine under a microscope
<br>
=== Treatment ===
*Sheep
*Sheep
**Plunge dipping; no less than 1 minute and must dip head at lease once
**Plunge dipping; no less than 1 minute and must dip head at lease once
**Can treat with avermectins or milbemycins by injection
**Can treat with avermectins or milbemycins by injection
*Cattle, horses and rabbits
*Cattle, horses and rabbits
**No licensed product for horses in the UK
**No licensed product for horses in the UK
**Cattle and rabbits can be treated with avermectins, milbemycins or topical acaricides
**Cattle and rabbits can be treated with avermectins, milbemycins or topical acaricides
To_Do_-_Kate [[Category:Integumentary_System_-_Mite_Infections]]
[[Category:To_Do_-_Clinical]]