Identifying Cat and Dog Ringworm: Key Symptoms & Diagno

Section 1: Acquiring Sample Material

When collecting sample material, it's crucial to choose hair or dandruff from the boundary of the affected area on cats or dogs. Use a surgical blade to gently scrape the skin until a slight bleeding occurs. This process helps in verifying the presence of mites and other microscopic ectoparasites, which might be associated with ringworm or easily mistaken for such conditions. Hair infected with Microsporum canescent can be plucked and examined under Wood's light for confirmation.

Section 2: Smear Testing Method

Place the scraped material on a slide and add 1 to 2 drops of 10% KOH solution (note that KOH solution decomposes within 10 to 20 minutes, so the test should be conducted immediately). Gently heat the slide to clear the hair and dandruff, then cover it with a coverslip. Under the microscope, look for the presence of hyphae or spores to diagnose a fungal infection. Additionally, the smear can be stained with DiffQuik and observed under a microscope to confirm a positive fungal infection by identifying distinct bluestained fungal spores.

Canine and feline dermatophytosis is a common disease in veterinary clinics and a zoonotic condition that poses serious threats to both animal and human health. During differential diagnosis, Wood's light can be an intriguing auxiliary tool for diagnosing infections with Mycobacterium canis, but it requires further precise examination. Direct examination of hair and skin scrapings, as well as fungal cultures, are necessary for confirmation. Fungal culture remains the "gold standard" for diagnosing dermatophytosis in cats and dogs. Treatment can only be terminated once a negative culture result is obtained.