Lactation

Question 1

Lactation

Answer 1

Milk secretion from the breast, which become enlarged during pregnancy

Question 2

Exposure to estrogen and progesterone during puberty induces

Answer 2

mammary gland growth

Question 3

Increased serum concentrations of prolactin during pregnancy causes

Answer 3

enlargement of mammary gland of the breast and increases the production of milk

Question 4

High level of progestion during pregnancy act directly on the breast by

Answer 4

stopping the ejection of milk

Question 5

Suckling promotes?

Answer 5

prolaction gene receptor expression and promotes continous production of milk

Question 6

High prolactin suppress?

Answer 6

cyclic production of gonadotrophin

Question 7

Milk biosynthesis

Answer 7

In mammary gland
Transported via bloodstream to secretory cells
Raw ingredients: amino acids, casein, lipids, lactose
Milk proteins synthesized within cells, mainly by ER and its attached ribosomes, then incorporated into golgi vesicles
Carbohydrates (lactose) synthesized in golgi apparatus
Individual components kept separate inside secretory cells
Out of cells in the form vesicles
Vesicle must pass through cytoplasm and plasma membrane to be deposited in lumen

Question 8

Milk production

Answer 8

In udder
Secrete colostrum
Cattle - average 305 days production 7000 kg of milk
Highest yield - 2 to 3 month post parturition
Can be kept in production for 5-6 lactation if yield still good

Question 9

Mammary gland consists of

Answer 9

parencyhma, stroma, alveolus, lobule, lobe and teat

Question 10

Mammary gland

Answer 10

estrogen & progesterone = optimal mammary growth, accelerate the rate of cell division in the mammary gland
Growth continues during early lactation until peak
During entire lactation period , rate od secretory cells loss exceeds the rate of division > udder contains more secretory cells at beginning than at the end
Weight + by age until reaches max skeletal growth
Significant + in mammary gland size during last month of pregnancy is due to accumulation of secretion in the alveoli

MARE
2 mammary gland, each teat has two orifice that leads to separate teat canal, lactiferous sinus and duct system
Skin of udder and teats have fine hair and many sebacous and sweat glands

Cow, goat, ewe - no hair on udder

Question 11

HORMONAL MAINTENANCE OF LACTATION

For milk synthesis

Answer 11

PROLACTIN - stimulates milk production
GH - maintenance of lactation
Oxytocin - milk let down stimulates myoepithelial cells of alveolus
Thyroid - maintenance of lactation in cattle.
Insulin - glucose is required for lactose synthesis and essential for maintenance of lactation
Corticosteroids - Intact adrenal glands are essential for maintenance of lactation
Parathyroid hormone - stimulates bone resorption of calcium and conversion of vitamin D to its OH2D3 which is necessary for the absorption of calcium from intestine

Question 12

MILK SECRETION

Answer 12

Certain stimulating factors caused this to occur
Pressure increase that direct the milk from the alveoli through the ducts
Stimulation of th teats in a reflex secretion of oxytocin from the posterior pituitary gland which on reaching the myoeithelial cells causes them to contract
Contraction of the myoepithelial cells (milk letdown)
Secretion of oxytocin for milk letdown is usually associated with tranquil (CALM) situation, and it can be inhibited by stressful situation or frigthened animals.

Question 13

Goat milk

Answer 13

Fat globules smaller and easier to be digestedd
Anti-arthritis and anti cancer
No agglutinis