Parasitic Skin Diseases of Small animals Flashcards
What are the three types of host parasite relationship?
Parasite = always disease
Parasite = carrier or minimal disease/marked hypersensitivity
Commensal parasite = rarely disease
What are some examples of arachnids that are parasitic to dogs?
Demodicosis, Sarcoptic mange, Cheyletiellosis, Trombiculiasis
What are some examples of arachnids that are parasitic to cats?
Cheyletiellosis, Trombiculiasis (demodecosis)
What are some examples of arachnids that are parasitic to horses?
Trombiculiasis, (demodecosis)
What is the main insect hypersensitivity syndrome affecting cats and dogs?
Flea bite hypersensitivity
What are the clinical signs of trombiculiasis (harvest mites)?
Can have red skin showing that the animal is mounting a reaction but no scratching so the animal isn’t bothered so don’t treat
Range from asymptomatic to severely pruritic
How is trombiculiasis diagnosed?
Strictly seasonal from July to September/October
Small, bright orange mites seen, larvae have 6 legs
Where about on the animal are harvest mites found?
Legs/face in horses
Feet/ears on cats and dogs
What is the treatment for Trombiculisis?
None licensed but fipronil (Frontline) works
What are the different types of Cheyletiella that infect the skin?
Cheyletiella blakei
Cheyletiella yasurgi
Cheyletiella parasitivorax
Is cheyletiellosis zoonotic?
Yes will bit people in close physical contact but can’t maintain an infestation in people
What are the clinical signs of cheletiellosis?
Scaling (walking dandruff)
Pruritis from mild-severe
Primarily on dorsal trunk
In cats see miliary dermatitis
How is cheletiellosis diagnosed?
Look for hook palpebrae of mite, attach eggs to hair shaft, look for them in coat brushing
What is the general principles of treatment for cheyletiellosis?
Often difficult requiring >6 weeks of treatment
Treat all in contact rabbits, cats and dogs
What products can be used to treat cheyletiellosis?
Non licensed but
For dogs can use amitraz, fipronil, selamectin, moxidectin and selenium sulphate shampoo
For cats can use fipronil, selamectin, moxidectin, ivermectin, selenium suphate shampoo
For rabbits can use ivermectin
What is demodecosis?
An inflammatory parasitic skin disease characterised by the presence of larger than normal numbers of demodectic mites
What species of demodex are common in the dog?
D. canis, D. injai, short bodied mite
What species of demodex are uncommon in the cat?
D. cati (USA), D. gatoi
What are the different manifestations of canine demodecosis?
Juvenile onset, localised - spontaneous recovery
Juvenile onset, generalised - inherited predisposition
Adult onset, localised or generalised - > 2 yrs age, suspect underlying immunosuppression
What causes juvenile onset demodecosis?
Transient inability to control mite population
How do dogs with demodecosis typically present?
For hair loss as not itchy disease
What is the treatment for demodecosis?
Minimum of 12 weeks of treatment and monitor by clinical exam and repeat scrapes/plucks
Avoid use of steroids (can develop deep pyoderma)
What is the aim of demodecosis treatment?
To reduce the burden to the level at which the body can manage
What is the prevalence of sarcoptic mange (scabies) in the different domestic species?
Dogs it is very common
Rare in cats and they are normally immunosuppressed
Notifiable in horses in the UK
