Pet Skin Health

Disease / Phenomenon

Pet skin health concerns the integrity and function of the skin and coat in companion animals, principally dogs and cats. Skin is the largest organ in these species too, serving as barrier, thermoregulator, sensory surface, and immune interface, and dermatologic complaints are among the most frequent reasons owners seek veterinary care. Common presentations include itching and overgrooming, redness, hair loss, scaling, hot spots, recurrent ear inflammation, and secondary bacterial or yeast infection. Underlying causes range from flea and other parasite hypersensitivity to environmental atopy, food-responsive dermatitis, endocrine disease such as hypothyroidism or hyperadrenocorticism, and nutritional deficiency. Persistent scratching degrades sleep, behavior, and quality of life for the animal.

Canine atopic dermatitis, the most studied condition, involves a compromised epidermal barrier with reduced ceramide and filaggrin content, allowing allergen penetration and transepidermal water loss. Keratinocytes release thymic stromal lymphopoietin and IL-33, driving a type 2 response with IL-4, IL-13, and IL-31 — the last acting through JAK signaling as a direct pruritogen. Mast cell degranulation, IgE production, and cutaneous microbial dysbiosis with Staphylococcus pseudintermedius and Malassezia amplify inflammation. Essential fatty acid status, oxidative balance, and the skin lipid matrix modulate severity. This page organizes these processes into pathways and biomarkers.