10 Milk Production Flashcards
Mammogenesis
Development of the mammary gland
Progesterone stimulates ______
alveoli growth
Estrogen stimulates _______
duct system growth
Lactogenesis
Production of milk by specialized epithelial cells and secreted into the lumen of alveolus
Stage I- Exocytosis
Most components of the aqueous phase (Casein and Lactose) are secreted by exocytosis
Casein- produced in the RER, transferred to Golgi, packaged into secretory vessicles
Lactose- produced in Golgi from glucose and galactose
Stage II-Lipid
Produced in the SER from FA and glycerol, coalesce into large droplets, are enveloped by the plasma membrane and released as a fat globule.
Stage III-Apical Transport
Water and electrolytes (Ca, Na, Cl, K, etc)
Stage IV- Transcytosis
Available during lactation in a healthy mammary gland. Allows transport of secretory IgA from the interstital space into milk. Other hormones such as IGF-1 are thought to be transported this way
Stage V-Paracellular
Allow transport of IgGs and leukocytes in late gestation and infection (mastitis). Products of the dissolution of the mammary cells during involution can also be cleared using this pathway.
Galactopoiesis
Secretion and continued production of milk
Prolactin and growth hormone stimulate
Suckling stimulates oxytocin release
Myoepithelial cell contraction
Removal of milk from mammary gland stimulates milk production
Involution
Atrophy of secretory cells induced by cessation of suckling, and decreased prolactin and GH
Embryology of Mammary gland
Modified sweat gland
Mammary ridges
Primary and secondary buds
Mammary gland anatomy
Lobes are made up of lobules and these are made up of alveoli which have specialized secretory epithelium that produces milk
Cow-Mammary gland anatomy
Inguinal
4 teats
1 canal/sinus per teat
Mare, Goat, Sheep-Mammary gland anatomy
Inguinal
2 teats
Mare-2-3ducts per teat
