What is an indication of erythematous skin during an examination?

Erythematous skin, which appears red and inflamed, is a clear indication of an underlying issue affecting the skin. This redness often signifies inflammation, which is commonly associated with skin irritation or infection. In dogs, such inflammatory responses can arise from a variety of causes, including allergies, parasites, or bacterial and fungal infections. The presence of erythema is a signal to veterinarians that there is a pathological process occurring that may require further investigation or treatment.

In contrast, healthy skin typically appears normal in color without redness or inflammation. Therefore, while erythematous skin signifies a problem, healthy skin would not exhibit these symptoms. Allergic reactions could also cause erythema, but they are just one of many potential causes, making the broader category of skin irritation or infection a more comprehensive answer.