Ectoparasites IV: Mites Flashcards
How do mites differ from ticks?
Size
Time/location on host
Some life cycle stages
Some aspects of morphology
What are the major mite groups?
Mange mites
Ear mites
Nasal mites
Hair-clasping mites
Are some animals at higher risk for mite infections?
Puppies and old dogs
Immunocompromised animals
What are diagnostic methods for mite infections?
Skin scraping
What are common clinical signs for mite infections?
Pruritus
Hair loss
Crusty lesions
What are complications of mite infections?
Secondary infection
How do you approach treatment for mite infections?
Treatment of the mite
Treat secondary problems
Are mite infections zoonotic?
Yes
Describe Sarcoptes scabiei (scabies mite)
One species
Host-adapted variants/strains
What is the range of hosts for Sarcoptes scabiei?
Wide range, except for cats (rare)
What is Sarcoptes scabiei common in?
Canids
Swine
Ferrets
Severe disease in red foxes
Where does the Sarcoptes scabiei life cycle occur?
On host, mostly in epidermis over 2-3 weeks
What areas does sarcoptic mange usually affect first?
Hairless areas
What does sarcoptic mange cause?
Usually papules, erythema, pruritus which can lead to hyperkeratosis, alopecia, self-trauma, secondary infections, crusitng
What is the common name of Sarcoptes scabiei in dogs? What are the lesion locations?
Itch mite
Lateral elbows
Lateral hocks
Edge of pinna
What is the common name of Sarcoptes scabiei in swine? What are the lesion locations?
No name, but it is common
Ears, back
What is the common name of Sarcoptes scabiei in cattle? What are the lesion locations?
Barn itch
Abdomen, neck, medial hind legs
What is the common name of Sarcoptes scabiei in sheep/goats? What are the lesion locations?
Head scab
Face, ears, ventrum
What is the common name of Sarcoptes scabiei in horses? What are the lesion locations?
No name
Neck, shoulders, face
What animals is mite infections reportable in?
Sheep/goats
Horses
What are methods of treatment for sarcoptic mange?
Various acaricides
What is the host of Notoedres cati?
Wild or domestic felids
Describe the lesions of notpedric mange of cats
Lesions begin on ears/face/neck then go to feet/perineum
Thick, scaly skin, alopecia, pruritus the self-trauma, systemic signs
Describe Psoroptes cuniculi
Common ear mites
Hosts: rabbits, goats, horses
Describe psoroptes ovis of large animals
Cattle, sheep, horses
Primarily in Southwest
Reportable
What is the life cycle of Psoroptes spp.?
Non-burrowing on skin
What is the common name of Psoroptes ovis in cattle? What are the locations of lesions?
Cattle scab
Back, tail head, shoulders
What is the common name of Psoroptes ovis in sheep? What are the locations of lesions?
Scab
Neck, back
What is the common name of Psoroptes ovis in horses? What are the locations of lesions?
Not common
Base of mane
What species is Psoroptes ovis reportable in?
Cattle
Sheep
What is the most common mite of cattle and horses?
Chorioptes spp.
What is the life cycle of Chorioptes spp.?
Non-burrowing on skin
What does Chorioptes spp. cause?
Chorioptic mange
What is the common name of Chorioptes in cattle? Where are the lesions?
Foot and tail mange, tail scab
Base of tail, udder, hind feet
What is the common name of Chorioptes in sheep/goats? Where are the lesions?
Foot and tail mange
Interdigital, base of tail, scrotum (sheep)
What is the common name of Chorioptes in horses (especially draft breeds)? Where are the lesions?
Foot mange, itchy leg
Foot, base of tail
What is a common ear mite in dogs, cats, and ferrets?
Otodectes cynotis
Describe what happens with Otodectes cynotis (ear mites)?
Canals become excessively moist
Cerumen; purulent black exudate
Inflammation—pruritis—self trauma
Secondary infection, ruptured ear drum
Where are Otodectes cynotis (ear mites) found?
Usually bilateral- head and neck
What is the method diagnosis of Otodectes cynotis?
Ear swabs
Where are most species of Demodex normal?
Normal fauna of skin
What is the transmission of Demodex spp.?
Direct contact (mother to neonate)
What species of Demodex are primary pathogens?
D. cornei in dogs
Describe the Demodex spp. life cycle
All stages develop on host within hair follicle lumen and sebaceous gland ducts
What are forms of demodicosis?
Squamous
Papulonodular
Describe squamous demodicosis
Localized or generalized
Primarily dogs, but also can occur with cat, horses, and sheep
Dry, scaly dermatitis, alopecia
Describe papulonodular demodicosis
Cattle, goats, pigs
Hair follicles/glands obstructed leads to nodules
Describe localized demodectic mange in dogs
Small, well-defined patchy lesions
Young dogs
Self-limiting, most spontaneously recover
Describe generalized demodectic mange in dogs
Usually underlying disease, except of D. cornei
Large, coalescing lesions leading to pruritus and secondary infection
No age predilection
Poor prognosis if no aggressive treatment
How common is feline demodectic mange? Does it have any predilections?
Rare
Any age/breed
What species of Demodex is normal flora in cats?
D. cati
Which species of Demodex is transmissible?
D. gatoi
Is demodectic mange common in cattle? Describe the lesions
Yes, pregnant/lactating
Nodular- neck, shoulders
Is demodectic mange common in sheep? Describe the lesions
Rare
Diffuse; scaly- neck, flank, shoulders
Is demodectic mange common in goats? Describe the lesions
Young or pregnant goats
Nodular- face, neck, axilla, udder
Is demodectic mange common in horses? Describe the lesions
Rare; chronic corticosteroids
Diffuse; scaly
Is demodectic mange common in pigs? Describe the lesions
Rare
Nodular- snout
What are the hosts of Cheyletiella spp.?
Dogs and cats
Are Cheyletiella spp. contagious?
Very contagious
Potentially zoonotic
What are Cheyletiella spp known as?
Walking dandruff
Fur mite
What is the life cycle of Cheyletiella?
Nonburrowing
What are the clinical signs of Cheyletiella in dogs? Cats?
Exfoliative dermatitis
Inflammation
Hyperaesthesia
Long-haired breed cats have similar signs espeically on head/trunk
What is the host of Pneumonyssoides caninum?
Dogs
What is Pneumonyssoides caninum?
Nasal mite
Where do all stages of Pneumonyssoides caninum occur?
In sinuses, superficial
What are the clinical signs of Pneumonyssoides caninum?
Rhinitis
Hyperemic mucosa
What is used to diagnose Pneumonyssoides caninum?
Rhinoscopy
Nasal swabs
What is used to treat Pneumonyssoides caninum?
Mainly avermectins
Describe Knemidocoptes mutans
Chickens, pet birds
Sever hyperkeratosis
Describe Dermanyssus gallinae
Chickens, wild birds
Anemia; decreased production
Describe Ornithonyssus sylvarium
Chickens, turkeys, etc.
Anemia; soiled vent feathers
