Unit 1: Ectoparasites in Dogs & Cats Flashcards
What organisms cause Cheyletiellosis?
Cheyletiella yasguri, blakeii, parasitovorax
Where does the life cycle of Cheyletiella take place?
On the surface of the animal; eggs are attached to hairs
T/F: Cheyletiella is zoonotic
True
What organism is this and how do you know?

Cheyletiella mite;
Has 4 pairs of legs and characteristic mouthparts with hooks used for grasping and holding onto hairs
What are clinical features of Cheyletiellosis?
Variable levels of pruritus;
Scaling, erythema progressing to crusts, excoriations;
Scales often found over the base of the tail in puppies;
Multiple animals often involved
What other species of animal gets Cheyletiella?
Rabbits
How is Cheyletiellosis diagnosed?
Direct observation with magnifying lens, tape prep, skin scrape, fecal float (bc animals lick themselves), flea comb
What are the treatments of choice for Cheyletiellosis?
Ivermectin, Selamectin (Revolution), and Advantage Multi
Topical acaricides for 3-4 treatments (lime sulfur, amitraz, carbamates)
In addition to drugs, what can be done to remedy Cheyletiellosis?
Disinfect the environment
What is Lynxacarus radovsky?
Feline fur mite that does not occur in the continental U.S.
What are synonyms for notoedric mange?
Feline scabies, head mange
What organism causes notoedric mange?
Notoedres cati
The life cycle of Notoedres cati is similar to _____.
Sarcoptes spp.
What is the significance of notoedric mange?
It is highly contagious and zoonotic
What are clinical signs/features of notoedric mange?
Intense pruritus around the head, ears and neck initially;
Clinical features = alopecia, scaling, erythema, crusts
What do Notoedres mites look like?
Have long, unjointed stalk on end of leg
What are treatments for notoedric mange?
Topical acaricides (lime sulfur and Bravecto for cats);
Systemic insecticides (ivermectin, revolution, advantage multi)
In addition to drugs, what can be used to remedy notoedric mange?
Treating all exposed cats and decontaminating the environment
What are synonyms for otoacariasis?
Ear mites, otodectic mange
What organism causes otodectic mange?
Otodectes cynotis
How long is the life cycle of Otodectes?
3 weeks
How is otodectic mange transmitted?
Direct contact
What does the pathogenesis of otodectic mange include?
Irritation and hypersensitivity reactions
What are the clinical features of otodectic mange?
Pruritus of one or both ears, head shaking, accumulation of dark/dry/granular exudate in the opening of the ear canal
How is otodectic mange diagnosed?
Direct visualization (otoscope), cytology
What organism is this and how do you know?

Otodectes mite - short, unjointed pedicels
How is otodectic mange treated?
Ears are cleaned thoroughly, and a topical miticidal agent or systemic acaricide is used
What are the topical miticidal agents used for otodectic mange?
Ivermectin, pyrethrins, rotenone, thiabendazole
What is the course of treatment for otodectic mange?
Apply topical agent daily or EOD for 3 weeks, apply insecticide to rest of body weekly
What are the systemic acaricides that can be used for otodectic mange?
Revolution, Adv Multi, Ivermectin, Bravecto (cats), Simparica/sarolaner (dogs)
What is the synonym for pediculosis?
lice infestation
What organisms cause pediculosis?
- Trichodectes canis* = dog
- Linognathus setosus* = (sucking) dog
- Felicola subrostratus* = cat
What is the lice life cycle?
17-21 days
How is pediculosis transmitted?
Direct contact and via fomites
What can lice cause?
Irritation, hypersensitivities, blood loss
What are clinical features of pediculosis?
Varying degrees of pruritus, alopecia, scale, crusts, erythema;
miliary dermatitis in cats;
lice and nits are visible
How is pediculosis diagnosed?
Visualization of lice or nits, flea comb, skin scrape
What is this?

Trichodectes canis
What is this?

Felicola subrostratus
What is this?

Felicola subrostratus
Felicola is a ____ louse.
chewing
How is pediculosis treated?
Topical parasiticides such as lime sulfur, carbamates, yrethrins, Adv multi, Selamectin, Fipronil, seresto collars
What lice is selamectin effective against?
biting
What live is fipronil (frontline) effective against?
Trichodectes
What lice are seresto collars effective against?
Trichodectes
Why are lice not considered a public health risk?
They are host-specific
What area does fly dermatitis affect?
Affects tip of ears or non-haired areas, caused by various fly spp.
What lesions are seen with fly dermatitis?
Crusts, hemorrhage, pruritus
How are fly dermatitis bites treated?
symptomatically
What is used for prophylaxis of fly dermatitis?
Insect repellants (permethrin)
What animals does fly strike affect?
Young or old and animals with disease
How is fly strike different from screwworm infestation?
Fly strike occurs in skin that is already devitalized, whereas screwworm burrows in healthy tissue
What is the classic appearance for fly strike?
honeycomb appearance

What caused this?

Fly strike
How is fly strike managed?
Manual removal of larvae, capstar, systemic antimicrobials, control shock
What should NOT be done when managing fly strike?
Topical insecticides due to open wounds
What causes cuterebriasis?
Larvae of Cuterebra spp botfly
Where do cuterebra larvae develop?
In SQ cyst with breathing pore
What lesions are present with cuterebriasis?
Nodule with small central opening that may be draining serosanguinous fluid
How is cuterebriasis treated?
Manual removal of larva and symptomatic care of the cyst
What is the synonym for pelodera dermatitis?
rhabditic mange
What organism causes pelodera dermatitis?
Pelodera strongyloides
What is associated with pelodera dermatitis?
Damp bedding (straw)
What lesions are seen with pelodera dermatitis?
Ventral erythema and pruritus
How is pelodera dermatitis diagnosed?
skin scrape
How is pelodera dermatitis treated?
Topical insecticides, ivermectin
What is pelodera dermatitis sometimes called?

“Waterline” disease; animal looks like it has been standing in the water
What is the synonym for ancylostomiasis?
hookworm dermatitis
What causes ancylostomiasis?
Migration of hookworm larvae
What causes ancylostomiasis lesions?
Irritation and hypersensitivity
What is the treatment for ancylostomiasis?
ivermectin, glucocorticoids for pruritus, disinfect environment
What is the pathogenesis of disease of ticks?
Mechanical irritation –> hypersensitivity reactions –> blood loss –> vectors of disease (RMSF, Lyme) –> secretion of toxins (neurotoxin)
How is tick infestation treated?
Manual removal, insecticide rinses/pour-ons, treating environment with sprays
How can ticks be prevented?
Collars, insecticides
What 3 products are good and labeled for ticks?
Revolution, Vectra 3D, isoxazolines
What tick is Revolution labeled for?
Dermacentor variabilis
What ticks is Vectra 3D labeled for?
- Rhipicephalus spp*
- Dermacentor spp*
- Ixodes spp*
- Amblyomma spp*
What ticks are the isoxazolines labeled for?
Brown dog tick (Rhipicephalus sanguineus)
American dog tick (Dermacentor variabilis)
Ixodes spp
Lone star tick (Amblyomma americanum)