ICAWC 2013 Barcelona, Spain - David Grant's presentation on Sarcoptic and Demodectic Mange

1. What you need to know about
demodectic and sarcoptic
mange
David Grant
B.Vet. Med. Cert.SAD. F.R.C.V.S.

2. Canine Demodicosis and
Canine Scabies
• Both canine demodicosis and canine
scabies are parasitic diseases caused by
mites invisible to the naked eye
• They are generally diagnosed from the
clinical signs and by skin scraping, hair
plucks or tape strips and identification of
the mite microscopically

3. CANINE DEMODICOSIS
• The disease is caused by Demodex canis
• This is a parasitic mite which is
transferred from the carrier mother to her
pups in the first 2 or 3 days of life
• Thereafter the disease is non-contagious
• This is an important distinction from
canine scabies which is highly contagious

4. DEMODEX CANIS LIFE
CYCLE IMAGES

5. DEMODEX CANIS

6. CANINE DEMODICOSISDemodex canis
•
CLINICAL FEATURES
•
•
The disease is more common in pedigree dogs, particularly short haired
Can occur in long-haired dogs e.g. Old English Sheepdog, West Highland
White and Afghan.
There are three forms of the disease. These are :Localised and generalised
A few cases present with foot lesions only. This is called Demodectic
pododermatitis
The majority of cases present in the first year of life-called juvenile onset
A minority present in older dogs more than 2 years of age and usually in
old age. These are called adult onset demodicosis and is associated with
suppression of the immune system. These have a guarded outlook
because there may be a serious underlying disease
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7. LOCALISED DEMODICOSIS

8. GENERALISED
DEMODICOSIS

15. ‘REDDE’ MANGE

16. CANINE DEMODICOSIS
Diagnosis
• Deep skin scrapings using blunted
number 10 scalpel blade
• Hair plucks
• Tape strips using scotch diamond ultratransparent
• Impression smears if deep pyoderma

17. CANINE DEMODICOSISlicensed treatment
• Amitraz(Aludex) 0.5% solution weekly
• Metaflumizone + amitraz spot
on(Promeris duo) every 2 weeks. This is
off label as manufacturer recommends
monthly
• Moxidectin + imidacloprid spot
on(advocate) weekly spot on

18. CANINE DEMODICOSIS
Unlicensed treatment
• Ivermectin. Orally at a dose of 0.3-0.6
mg/kg daily Do not use in collies and
related breeds-neurotoxic. Prudent to
start with 0.1 mg/kg and build up over a
week or two until at the upper dose rate.
Commonly first choice in many parts of
the world

19. Before treatment with promeris

21. Before treatment with amitraz

23. Before treatment with
ivermectin

27. Demodectic pododermatitis
before ivermectin treatment

29. CANINE SCABIES
(Sarcoptic mange)
• Caused by the parasitic mite Sarcoptes
scabiei var canis

30. SARCOPTES SCABIEI

31. Canine Scabies
Clinical signs

32. CANINE SCABIES
• DIAGNOSIS
• History, physical examination, skin scrapings, ELISA
test and/or trial therapy
• Often mildly pruritic initially but gets markedly worse
without treatment
• Sarcoptes can be difficult to capture even with
numerous skin scrapings therefore• Trial therapy should be given to any dog suspected of
having scabies even if scrapings are negative

33. CANINE SCABIES
 TREATMENT
 Amitraz-5 to 6 weekly baths recommended, at a dilution of 250
ppm
 Cannot be used in Chihuahuas, puppies less than 12 weeks of
age, pregnant or lactating bitches
 Selamectin(Stronghold)is licensed-spot on every month for three
applications
 Moxidectin(Advocate) is licensed-spot on every two weeks for
three applications
 With therapeutic trial veterinarian should apply and monitor
(Ivermectin is effective at 200 mcg/kg subcutaneous injection x 3 at
10 day intervals but is not licensed)

34. CANINE SCABIES-treatment

35. SUMMARY
CANINE DEMODICOSIS
CANINE SCABIES
• Caused by Demodex canis
• Not contagious
• Not usually pruritic(except
if severe secondary
infection)
• Can be difficult to cure and
labour intensive
• Licensed and unlicensed
products available with
cure rate c 90%+
• Caused by Sarcoptes
scabiei var canis
• Highly contagious
• Severe pruritus which
escalates
• Most cases easy to cure
• Effective licensed products
available - seldom need to
use unlicensed. Cure rate
approaching 100%