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→Non-Burrowing Mites
===''Psoroptes''===
===''Psoroptes''===
*In [[Parasitic skin infections - Pathology#Psoroptic mites|psoroptic skin infestation]]
*In [[Parasitic skin infections - Pathology#Psoroptic mites|psoroptic skin infestation]]
'''Recognition'''
*Oval shaped
*Long legs
*Funnel shaped suckers on '''segmented''' pedicels
*1-2mm in length
'''Life Cycle'''
*Confined to skin surface
*Feed on serous exudate by siphoning
*Adult female can lay up to 100 eggs during her life time (one month)
*10 day life cycle
*2 nymphal stages
====''Psoroptes cuniculi''====
====''Psoroptes cuniculi''====
*Parasite of rabbits
*Parasite of rabbits
*Common among conventional rabbits
*Clinical
*Transmitted via contact
*Adapted to living in an aural environment
**Appearance; examination for mites (low magnification).
'''Pathogenesis'''
*Control
*The ears are painful and itch intensely
*Affected rabbits shake their heads and scratch their ears
*The inner surfaces of the pinnae are covered with brown, scaly, fetid material, and the skin beneath is raw
*Mites are grossly visible
*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
'''Diagnosis'''
*Examination for mites (low magnification)
*Appearance
'''Control'''
*Infestations are difficult to eliminate from a colony
**Ivermectin is usually effective
====''Psoroptes ovis''====
====''Psoroptes ovis''====
*Life cycle last 14 days
*Life cycle last 14 days
*Transmitted by direct contact between sheep
*Indirect transmission can also occur
'''Pathogenesis'''
'''Pathogenesis'''
*Causes '''sheep scab'''
*Causes '''sheep scab'''
**Wool loss, restlessness, biting, scratching of infested area and decreased productivity through a decreased weight gain
**Wool loss, restlessness, biting, scratching of infested area and decreased productivity through a decreased weight gain
**Usually seen in late autumn and early winter (although may also iccur in late summer)
**Population numbers decline after shearing due to a change in the microclimate, then build up again as the fleece grows
**Notifiable in UK
*Mites found under scabs and in skin folds
*Lesions most common on flanks, neck, back and shoulders
*Lesions most common on flanks, neck, back and shoulders
*Causes pruritic condition of cattle
*Causes pruritic condition of cattle
*Active in keratin layer
*Mouthparts abrade the skin
*Antigenic material in mite faeces can lead to hypersensitivity reactions
'''Diagnosis'''
*Skin scraing
*KOH added
*Warm slide over a bunson
*Examine under a microscope
===''Chorioptes bovis''===
===''Chorioptes bovis''===
*In [[Parasitic skin infections - Pathology#Chorioptic mites|skin infestation]]
*In [[Parasitic skin infections - Pathology#Chorioptic mites|skin infestation]]
*Surface parasite of horses and cattle
*Less pathogenic than ''Psoroptes''
**Mouthparts cannot pierce the skin
'''Recognition'''
*Oval body
*Long legs
*Cup shaped suckers on '''unsegmented''' pedicels
'''Pathogenisis'''
*Chorioptic mange
**Often seen in rough-legged horses with heavy feathering
**Induce crusty skin and lesions below the hocks and knees
*Mild condition in cattle
**Rubbing and scratching
**Hide damage
*Usually found on legs of sheep
**Mild condition
===''Otodectes cynotis''===
===''Otodectes cynotis''===