Your pet regularly has dandruff along their back or on top of their head, or their coat is greasy and has a strong odor. They may be suffering from seborrhea or squamosis. What causes this? How can you relieve it?
Where Do These Flakes Come From?
The stratum corneum, the outermost layer of the epidermis, is constantly and regularly renewed. The elements that make it up—corneocytes—are dead cells. Over a cycle lasting roughly three weeks in dogs, the skin regenerates as cells from the deeper layers of the epidermis gradually rise to the surface. They then die and detach from the skin, a process known as desquamation. This is a normal process and typically invisible to the naked eye.
Occasionally, for various reasons, the removal of these dead cells may not occur optimally. The flakes then become visible—these are the infamous dandruff flakes!
The causes of this condition can be varied and may be secondary to another disease (such as leishmaniasis) or primary (such as a genetic disorder like ichthyosis, which appears in certain breeds like the Golden Retriever).
Keratinization disorders can therefore manifest as excessive desquamation or, conversely, excessive keratinization—meaning a thickening of the stratum corneum.
Why Does My Pet Have Oily Skin?
Seborrhea refers to an abnormal production of sebum, the "oil" secreted by the sebaceous glands. This substance is part of the surface lipid film and thus helps maintain an effective skin barrier. It also provides antimicrobial protection and gives the skin suppleness as well as a shiny coat. Its production is regulated by numerous hormonal, nutritional, and genetic factors.
Sometimes sebum production can be disrupted, either in quantity or quality. This is known as seborrhea. It may cause unpleasant odors, greasy or dull fur, and microbial overgrowth.
Primary seborrhea (e.g., granulomatous sebaceous adenitis in the Akita Inu) is distinguished from secondary seborrhea, which results from another condition (e.g., atopic dermatitis or cutaneous lymphoma). In the former case, the animal does not experience itching, but inflammation and secondary infections may occur.
How to Manage Keratoseborrheic Conditions?
Most of the treatment relies on the use of topical products, typically shampoos. Your veterinarian will recommend keratomodulators aimed at normalizing the production and shedding of skin cells, as well as antiseborrheics to limit sebum production. Applying emollients is also advised to maintain proper skin hydration. In case of secondary infection, your veterinarian may prescribe an antiseptic shampoo, or even antibiotics if deemed necessary. Topical products are usually applied several times a week. If the primary cause is managed, the frequency of topical applications can gradually be reduced as your four-legged companion’s skin condition improves.
Sources:
DermaVet – Veterinary Dermatology: this website is packed with insightful and relevant information on canine and feline dermatology.
Topical Therapy in Veterinary Dermatology: A Review of Recommended Treatments for Common Canine and Feline Dermatoses
