Changes

===Sweat Glands===

===Sweat Glands===

Sweat is considered to be the product of [[Necrosis - Pathology#Apoptosis|apoptosis]] releasing cell contents into the gland lumen, together with secretion where exocytosis, microapocrine blebbing, transcellular and perhaps paracellular processes involved in varying degrees.  Sweat is composed of secretions and cellular debris and includes inorganic ions, water, immunoglobulins, amino acids and waste products including urea and lactic acid.  Equine sweat is rich in proteins including glycoproteins, albumin and gammaglobulins, which cause the sweat to froth and the horse is said to "lather up".

Sweat is considered to be the product of [[Necrosis - Pathology#Apoptosis|apoptosis]] releasing cell contents into the gland lumen, together with secretion where exocytosis, microapocrine blebbing, transcellular and perhaps paracellular processes involved in varying degrees.  Sweat is composed of secretions and cellular debris and includes inorganic ions, water, immunoglobulins, amino acids and waste products including urea and lactic acid.  Equine sweat is rich in proteins including glycoproteins, albumin and gammaglobulins, which cause the sweat to froth and the horse is said to "lather up".

===Sebacious Glands===

===Sebaceous Glands===

One or more sebaceous glands surround each '''hair follicle''' at a point about 1/3 of its length beneath the skin's surface.  Each gland is composed of numerous ''acini'' attached to a common '''excretory duct''' through which they discharge their secretions ('''sebum''') onto the hair shaft and epidermis.  In the skin and eyelids such glands release the cell contents together with secretory products with holocrine secretion.  This secretion involves [[Necrosis - Pathology#Apoptosis|apoptosis]] in which the secretory products and cell debris are released into the gland lumen.  The secretory products vary from species to species and include various fatty acids, diglycerides, cholesterol, diesters, wax esters and giant-ring lactones. The function of sebum is that of an emolient of the hair and skin, preventing excessive dryness.  It may combine with '''sweat''' to form an emulsion within the stratum corneum and a form of cement around the hair pores preventing bacterial invasion of the epidermis.  Sebum is also released from the glands during piloerection, as the action of the [[Hair - Anatomy & Physiology#Hair Types|arrector pili]] muscle squeezes the gland as it raises the hair.

One or more sebaceous glands surround each '''hair follicle''' at a point about 1/3 of its length beneath the skin's surface.  Each gland is composed of numerous ''acini'' attached to a common '''excretory duct''' through which they discharge their secretions ('''sebum''') onto the hair shaft and epidermis.  In the skin and eyelids such glands release the cell contents together with secretory products with holocrine secretion.  This secretion involves [[Necrosis - Pathology#Apoptosis|apoptosis]] in which the secretory products and cell debris are released into the gland lumen.  The secretory products vary from species to species and include various fatty acids, diglycerides, cholesterol, diesters, wax esters and giant-ring lactones. The function of sebum is that of an emolient of the hair and skin, preventing excessive dryness.  It may combine with '''sweat''' to form an emulsion within the stratum corneum and a form of cement around the hair pores preventing bacterial invasion of the epidermis.  Sebum is also released from the glands during piloerection, as the action of the [[Hair - Anatomy & Physiology#Hair Types|arrector pili]] muscle squeezes the gland as it raises the hair.

===Specialised Glands===

===Specialised Glands===

Specialised glands in the horse exist in the [[Hoof - Horse Anatomy#Frog|frog]].

Specialised glands in the horse exist in the [[Hoof - Horse Anatomy#Frog|frog]].

The '''thoracic and cranial abdominal mammary glands '''drain via '''cranial superficial epigastric veins''' into the '''internal thoracic vein'''. '''Caudal abdominal and inguinal mammary glands '''drain via '''caudal superficial epigastric veins''' into the '''external pudendal vein'''.  

The '''thoracic and cranial abdominal mammary glands '''drain via '''cranial superficial epigastric veins''' into the '''internal thoracic vein'''. '''Caudal abdominal and inguinal mammary glands '''drain via '''caudal superficial epigastric veins''' into the '''external pudendal vein'''.  

===Lymphatics===

===Lymphatics===

The more caudal mammary glands drain to the  '''superficial inguinal lymph node''' and the more cranial mammary glands to the axillary or sternal lymph nodes.  

The more caudal mammary glands drain to the '''superficial inguinal lymph node''' and the more cranial mammary glands to the '''axillary or '''sternal''' lymph nodes.  

===Innervation===

===Innervation===

Somatic innervation is via the ventral rami of the spinal nerves.  Mammary branches of the '''pudendal nerve''' supply the caudal aspect of the udder. There is sympathetic innervation to the blood vessels and teat sphincter smooth muscle. Mammary glands also have major influence from endocrine hormones.

Somatic innervation is via the ventral rami of the spinal nerves.  Mammary branches of the '''pudendal nerve''' supply the caudal aspect of the udder. There is sympathetic innervation to the blood vessels and teat sphincter smooth muscle. Mammary glands also have major influence from endocrine hormones.

'''Further information on the equine hoof, with particular reference to its role within the musculoskeletal system, can be found [[Hoof - Horse Anatomy|here]]'''.

'''Further information on the equine hoof, with particular reference to its role within the musculoskeletal system, can be found [[Hoof - Horse Anatomy|here]]'''.

[[Category:Horse Anatomy]]

[[Category:Horse Anatomy]]