Canine Seborrhea Study Guide

Overview and Clinical Importance

Seborrhea (also called seborrheic dermatitis) is a common keratinization disorder in dogs characterized by defective keratinization of the epidermis, hair follicles, and claws, resulting in abnormal scale formation, excessive greasiness, and often secondary infections. Understanding seborrhea is essential for the NAVLE because it is frequently encountered in clinical practice and requires systematic diagnostic workup to identify underlying causes.

The keratinization cycle normally takes approximately 21 days in healthy dogs. In seborrheic dogs, this cycle is dramatically accelerated to approximately 7-8 days, leading to accumulation of scale and abnormal sebum production. This accelerated epidermal turnover is well-documented in research on affected Cocker Spaniels.

Pathophysiology of Keratinization

Keratinization is the process by which the protective outer layer of skin (stratum corneum) is constantly renewed by new skin cells migrating from the basal layer. Keratin is a structural protein that gives skin and hair its form and creates a protective outer coating.