A

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Alopecia: the partial or complete absence of hair from areas of the body where it normally grows; baldness.

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Anagen: the growing phase of a hair follicle.

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Anatomical: relating to bodily structure. "anatomical area»: area of the body

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Appendages: a thing that is added or attached to something larger or more important.

 

Arrector muscle: The arrector pili muscles are small muscles attached to hair follicles in mammals.

 

Autosomal: An autosome is a nonsexual chromosome (as opposed to the gonosome which is a sexual chromosome).

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B

 

Basement membrane: Extracellular matrix lining an epithelium, thus separating it from the underlying connective tissues. It protects the underlying tissues and ensures a certain permeability to different molecules, in particular nutrients.

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Bergamasco: Bergamasco Shepherd, Italian dog breed

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C

 

Carbohydrates: any of a large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose. They contain hydrogen and oxygen in the same ratio as water (2:1) and typically can be broken down to release energy in the animal body

 

Catagen : a short transitional phase of the hair growth cycle between anagen and telogen that usually lasts between 10 to 20 days and during which the lower portion of the hair follicle regresses and hair growth ends

 

Cortex: The cortex of the hair shaft is located between the hair cuticle and medulla and is the thickest hair layer. It also contains most of the hair's pigment, giving the hair its color.

 

Cuticle: the outer cellular layer of a hair.

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D

 

Dandruff: small pieces of dead skin in the coat.

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Degeneration: deterioration and loss of function in the cells of a tissue or organ.

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Dermal: relating to the skin or dermis.

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Dermal Papilla: The dermal papillae (DP) (singular papilla, diminutive of Latin papula, 'pimple') are small, nipple-like extensions (or interdigitations) of the dermis into the epidermis

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Desmosomes: (/ˈdɛzməˌsoʊm/; "binding body"), also known as a macula adherens (plural: maculae adherentes) (Latin for adhering spot), is a cell structure specialized for cell-to-cell adhesion. 

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Desquamation: Elimination of the superficial layers of the epidermis in the form of small lamellae (scales).

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E

 

Effluvium: The so-called "Effluvium" shedding is a sudden and abundant loss due to a specific event generally of hormonal or psychological origin.

 

Epidermis: the surface epithelium of the skin, overlying the dermis.

 

Eumelanin: a dark melanin pigment

 

Exogen: a phase in the life cycle of a hair follicle in which a hair exits the follicle.

 

External Epithelial Sheath: The external epithelial root sheath of a hair (or hair follicle) is one of the two layers of the dermal root sheath, which is sometimes called simply the "root sheath" of a hair. The dermal root sheath of a hair consists of two layers of epidermal surrounded by an outer sheath of connective tissue.

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F

 

Fibroblast: a cell in connective tissue which produces collagen and other fibers.

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Follicle: a small secretory cavity, sac, or gland.

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Follicular: of the nature of, composed of, or characteristic of a follicle or follicles.

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Follicular capital: The amount of follicle the body has

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H

 

Hair bulb: deep part of the follicle

 

Hormones: Chemical substance produced by a group of cells or an endocrine gland and which exerts a specific action on the functioning of an organ.

 

Hypodermis: the conjunctive tissue immediately beneath the epidermis

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I

 

Infundibulum: In anatomy, an infundibulum is a hollow, funnel-shaped structure.

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Intercellular cement: A substance bonding epithelial cells together.

 

Internal Epithelial Sheath: The internal epithelial root sheath of a hair (or hair follicle) is one of the two layers of the dermal root sheath, which is sometimes called simply the "root sheath" of a hair. The dermal root sheath of a hair consists of two layers of epidermal surrounded by an outer sheath of connective tissue.

 

Isthmus: a narrow organ, passage, or piece of tissue connecting two larger parts.

 

IWL: Insensible Water Loss. Loss of water by evaporation from the skin of perspiration so slight that the subject is unaware of it.

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K

 

Keratinocytes: an epidermal cell which produces keratin

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L

 

Lactation: Secretion and flow of milk, in female mammals.

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Langerhans cells: Langerhans cells (LC) are members of the dendritic cells’ family, residing in the basal and suprabasal layers of the epidermis and in the epithelia of the respiratory, digestive, and urogenital tracts. They specialize in antigen presentation and belong to the skin immune system (SIS).

 

Lipids: any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents. They include many natural oils, waxes, and steroids.

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M

 

Mechanical stress: Mechanical Stress is a measure of internal forces acting on a body when an external force is applied to it.

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Medulla: the inner region of an organ or tissue, especially when it is distinct from the outer region or cortex (as in a kidney, an adrenal gland, or hair).

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Melanocytes: Cell capable of producing melanin.

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Merkel cells: Merkel cells, also known as Merkel-Ranvier cells or tactile epithelial cells, are oval-shaped mechanoreceptors essential for light touch sensation and found in the skin of vertebrates.

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Mosaic shedding: continuous shedding phenomenon

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Mucous: relating to, producing, covered with, or of the nature of mucus.

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N

 

Nutrients: a substance that provides nourishment essential for the maintenance of life and for growth.

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O

 

Ostium: Opening at the top of the follicle allowing the hairs to come out.

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P

 

Pathogens: a bacterium, virus, or other microorganism that can cause disease.

 

Phaeomelanin: red pigment in dogs and cats

 

Phenotype: Set of apparent characteristics of an individual (opposite to the genotype).

 

Photoperiod: the period each day during which an organism receives illumination; day length.

 

Piloerection: Goosebumps or piloerection, pilo-motor reflex or even piloerection is a reaction of the body to certain situations such as cold, fear, etc.

 

Proteins : any of a class of nitrogenous organic compounds which have large molecules composed of one or more long chains of amino acids and are an essential part of all living organisms, especially as structural components of body tissues such as muscle, hair, etc., and as enzymes and antibodies.

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R

 

Renal: relating to, involving, or located in the region of the kidneys

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Rex breeds: All breeds of cats whose genes make their hair twisted.

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S

 

Sebaceous gland: small oil-producing gland present in the skin of mammals.

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Sebum: A fatty secretion produced by the sebaceous glands.

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Secretion: Physiological phenomenon by which a tissue produces a specific substance.

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Stratum corneum: superficial layer of the epidermis

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Superficial: existing or occurring at or on the surface.

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T

 

Thermoregulation: Regulatory mechanism by which the internal temperature of the body of homeothermic animals remains constant.

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Tylotrich: Tylotrich hairs are large hair follicles scattered throughout the body. The hairs are larger than normal hairs and contain one large hair surrounded by a complex of neurovascular tissue at the level of the sebaceous gland. They are believed to be rapid adapting mechanoreceptors.

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V

 

Vascularized: (of a tissue or structure) provided with vessels, especially blood vessels; made vascular.

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Vibrisses: Vibrisses or Whiskers are sensory organs specific to certain animals, including mammals. These are long keratin extensions that transmit their vibrations to a sensory organ located at their base.