Which organism is classically associated with canine demodicosis?

• A. Demodex canis
• B. Sarcoptes scabiei
• C. Ixodes scapularis
• D. Notoedres cati

Answer: (A)

Demodex canis is the organism classically linked to canine demodicosis. This tiny mite lives in hair follicles and sebaceous glands of dogs and is normally present in small numbers, but overgrowth occurs when the immune system is compromised or during certain predispositions, leading to the characteristic hair loss and sometimes inflammation seen with demodicosis. Diagnosis is typically made by deep skin scrapings or hair plucks that reveal the mites in the follicles. Transmission is often from mother to puppies during nursing in juvenile cases. The other organisms listed cause different conditions: Sarcoptes scabiei causes canine scabies with intense itching and crusting; Ixodes scapularis is a tick; Notoedres cati causes feline mange.