Skin Structure

Cat skin has two distinct strata. The surface, or epidermis, consists of about 40 layers of dead, flattened cells, embedded in fat-rich sebum, an oily skin secretion. Beneath this "cornified" layer is the living epidermis, or "basal" area, about four cells thick.

The epidermis is not very strong, but plays an important role in the bodys immune system. In normal circumstances, it takes about three weeks for cells to migrate from the basal layer to the cornified layer, but the process speeds up when the skin is injured, reducing the replacement time to two weeks.

Beneath the epidermis is the dermis, the major structural component of the skin. It consists of strong elastic connective tissue, and contains glands, blood vessels, nerves, and receptors.

Each hair follicle has an associated sweat gland and sebaceous gland, buried in the dermis. The sebaceous glands produce fatty sebum, which controls bacteria and helps to give hair its sheen.

They are concentrated on the neck and rump, and especially around the lips and on the chin. Specialized sebaceous glands line the eyelids and produce an oily protective film for the eyes. Other specialized sebaceous glands around the anus and between the toes may produce         pheromones, or sex scents.

Unlike humans, cats do not sweat to control their body temperature; they pant inefficiently or lick themselves. Sweat-gland secretions maintain the skin's pliability, excrete waste, provide nutrients for the skin's microflora, and contain substances that protect the body from chemicals and dangerous microbes.

They probably also secrete pheromones. Sweat glands associated with hair follicles are called epitrichial (formerly apocrine). Atrichial (formerly eccrine) glands, such as those on the footpads, open onto the skin, rather than into hair follicles.