Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ansc 201 > Lactation > Flashcards

Lactation Flashcards

1
Q

What are the purposes of lactation?

A
  1. Provide nourishment
  2. Provide immunity (colostrum)
  3. Provide quick energy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the locations of some of the lactating glands?

A

Pectoral region
Inguinal region
Abdominal region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How can we categorize some of the structural arrangements of lactating organs?

A

number of glands
number of teats
number of streak canals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the alveolus?

A

The basic milk secreting unit.
Composed of a lumen, epithelial cells, and myoepithelial cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the function of the epithelial cells of the alveolus?

A

synthesize milk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the function of the myoepithelial cells of the alveolus?

A

muscular cells that squeeze the alveolus to eject the milk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the arrangement of alveoli

A

they are arranged in lobes or smaller groups called lobules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the order of the flow of milk

A

Milk enters the lumen and exits from the ducts. It enters into a gland cistern, then a teat cistern before exiting the body through a streak canal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe a cow’s udder.

A

The udder is divided into four separate quarters, each independent in their milk producing function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the growth and development of the mammary gland prior to birth.

A

The mammary streak differentiates into buds and sprouts, which later become ducts. The teats develop.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the growth and development of the mammary gland from birth to the onset of puberty.

A

Streak canal develops, further development of the teat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the growth and development of the mammary gland from the onset of puberty to the beginning of the first pregnany.

A

major ducts get larger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the growth and development of the mammary gland during pregnancy.

A

early: large ducts and development of smaller ducts
late: alveoli and lobes are forming

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the growth and development of the mammary glands during lactation.

A

Alveoli begin to function and increase in number. After the peak of lactation, there is a gradual decline in the number of functioning alveoli.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the growth and development of the mammary glands after termination of lactation.

A

Alveoli and lobes regress

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is involution?

A

The process in which secretory tissue and ductile tissue regress after the termination of lactation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens to the mammary glands during subsequent gestations and lactations?

A

The cycle of developing alveoli and involution repeats.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does somatotropin influence the mammary gland?

A

It is primarily responsible for mammary growth prior to puberty. The growth caused by somatotropin is isometric, meaning growth is occurring at the same rate as other body parts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does estrogen influence the mammary gland?

A

It is responsible for duct and cistern growth beginning at puberty. This growth is allometric, meaning that it is growing at a faster rate than the rest of the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does progesterone influence the mammary gland?

A

It stimulates the development of the alveoli and lobes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is prolactin and how does it influence the mammary gland.

A

Prolactin is a hormone released by the anterior pituitary gland. It is essential for milk formation and secretion, as well as maintaining lactation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do glucocorticoids, somatotropin, and adrenocorticotropin influence the mammary gland?

A

They work with prolactin to initiate and maintain lactation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How does thyroxin affect the mammary gland?

A

In increases the metabolic rate of the tissue in the mammary gland.

24
Q

How does parathyroid hormone affect the mammary gland?

A

It regulates the calcium levels in the blood, and is less active when the animal is not lactating.

25
Q

How does oxytocin affect the mammary gland?

A

It causes the myoepithelial cells to contract, forcing milk ejection.

26
Q

What is parturient paresis and what is it caused by?

A

Parturient paresis is milk fever. It occurs when an animal has offspring and low parathyroid hormone levels. This prevents calcium from being mobilized in an effective manner to meat the animal’s needs. Since muscles need calcium to function, not having enough of it in the blood makes it difficult for the animal to stand.

27
Q

Describe the hormonal response during gestation.

A

High levels of progesterone decrease prolactin release and decrease prolactin effect.

28
Q

Describe the hormonal response just prior to parturition.

A

Lower progesterone levels and higher estrogen levels allow for an increase in prolactin release and increases the prolactin effect.

29
Q

Describe the processes of milk synthesis.

A
  1. Filtration (water)
  2. Selective absorption (minerals, vitamins)
  3. Cell metabolism (casein, lactose, milk fat)
30
Q

What are the blood precursors to lactose synthesis in a monogastric?

A

glucose in the blood

31
Q

What are the blood precursors to lactose synthesis in a ruminant?

A

glucose from blood and liver via gluconeogenesis using propionic acid

gluconeogenesis is a necessary step because most of the glucose is converted into VFA’s, and not much of it is in the blood

32
Q

What is the blood precursor to milk lipids in monogastrics?

A

blood lipids and glucose

33
Q

What is the blood precursor to milk lipids in ruminants?

A

blood lipids and acetic acid

34
Q

What is lactose synthase?

A

an enzyme found only in lactating tissue; derived from alpha-lactalbumin

lactose is the milk solids component most closely tied to yield

35
Q

How are vitamins and minerals acquired for milk production by monogastrics and ruminants?

A

Minerals are mainly absorbed, and so are vitamins.

Ruminants can synthesize their own supply of the B complex vitamins and Vitamin K

36
Q

What are the phases of milk secretion?

A
  1. Synthesis
  2. Secretion
  3. Rest and regeneration
37
Q

How does intramammary pressure relate to milk flow?

A

fast: low pressure
slow: moderate pressure
stop: high pressure

Frequent milk removal will keep the pressure low so that there is a fast rate of secretion.

38
Q

How are casein and lactose released from a lactating mammary cell?

A

Vesicles merge to form larger vesicles. They then become continuous with the cell membrane, and the micelles are released from the cell.

39
Q

How are fat globules released from a lactating mammary cell?

A

The cell membrane envelops the fat globule, and it pinches off from the cell, leaving part of the cell membrane surrounding the fat globule.

40
Q

Describe milk let-down.

A

Stimuli: hypothalamus tells posterior pituitary to release oxytocin in response to suckling, sound, etc

Oxytocin travels through the bloodstream to the udder to stimulate the release of milk.

41
Q

What can inhibit milk let-down?

A

Disturbing the cow could cause epinephrine to be released, inhibiting milk let-down.

42
Q

How is milk removed?

A

suckling
hand milking
mechanical milking

43
Q

Describe the metabolic burdens of lactation during all of its stages

A

Beginning: negative energy balance, fat is mobilized

Mid-Lactation: zero energy balance (energy intake = energy outtake)

Late Lactation: positive energy balance (weight gain)

Management schemes are designed to minimize negative energy balance at the beginning of lactation and prevent obesity at the end of lactation.

44
Q

What is persistence? What trends exist with it?

A

How well an animal maintains her milk production level throughout lactation.

Older animals tend to have higher peak production but are less persistent than younger animals.

45
Q

What is mastitis?

A

Mastitis is an inflammation of the mammary gland. It’s usually caused by infection, and it is the most costly issue in the dairy industry since it usually results in lower milk production.

46
Q

What ligament separates the mammary into right and left halves?

A

median suspensory ligament

47
Q

How can bacteria enter the mammary system most easily?

A

teat opening

48
Q

For each pound of milk produced, how many pounds of blood must pass through the udder?

A

400 lbs. of blood

49
Q

What three major items pass through the inguinal canal?

A

blood vessels
lymphatic tissues and vessels
nerves

50
Q

Do arteries or veins have thicker walls?

A

arteries

51
Q

What are some functions of the lymphatic system?

A

It returns interstitial fluid to the bloodstream and aids in killing bacteria.

52
Q

Near the time of parturition, animals often accumulate large quantities of lymph in their mammary systems. What is this condition called?

A

Udder adema

53
Q

The streak canal streaks what fibrous protein that helps prevent the invasion of mastitis-causing organisms?

A

keratin

54
Q

What closes the teat end between milkings?

A

a muscular sphincter

55
Q

Where does milk collect between milkings in the alveolus?

A

the lumen

56
Q

What might cause the release of epinephrine into the blood stream of an animal and decrease the effectiveness of oxytocin?

A

fright, rough handling, stress, unusual circumstances

Ansc 201 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions