Test 4: lactation Flashcards
(75 cards)
1
Q
suckle
A
To give a neonate milk from an udder
– To draw milk from the udder
2
Q
Suckling
A
A young unweaned animal
3
Q
Lactation
A
Production of milk
– Period following parturition when milk is secreted from
mammary glands
4
Q
protherian
A
monotremes
platypus
young hatched from egg
mammary gland has no nipples
milk secreted onto hair
5
Q
methatherian
A
marsupials
Short gestation
- Offspring not well developed at birth
- Young crawl to nipple and remain attached delayed implantation
6
Q
___ are true placental mammals
A
eutherian
7
Q
A
primary mammary bud (ectodermal)
8
Q
A
secondary mammary bud
9
Q
A
3rd step of mammary development: primary, secondary, canalization
10
Q
camel has how many teats
A
4 teats with two canals per teat
11
Q
cows have how many teats
A
4 teats: 1 canal/cistern
12
Q
mare have how many teats
A
2 with 2-3 ducts per teat
13
Q
goats have how many teats
A
2 teats: 1 canal/cistern
14
Q
ewe have how many teats
A
2 with 1 canal/cistern
15
Q
how many teats for sow
A
a bunch with 2-3 ducts per teat
16
Q
bitch have how many teats
A
8- abdomen and thoracic with 5-6 ducts per teat
17
Q
primates have how many teats
A
2 with 8-10 ducts per teat
18
Q
A
19
Q
suspensory system of the udder
A
medial and lateral suspensory ligamant
20
Q
milk vein
A
develops in cows
subcutaneous abdominal vein
21
Q
A
22
Q
yellow elastic tissue is found where in the udder
A
midline → strong suspensory
23
Q
A
24
Q
A
lacting buck→ holding the scrotom
25
do stallions have teats?
no
26
do boars have teats?
yes
27
3 ways to prevent infection in mammary gland
**Physical Barriers**
– Streak canal (smooth muscle, keratin)
– Rosette of Furstenberg
**Cellular Immunity**
– Granulocytes, lymphocytes, macrophages
**Humoral immunity**
– Immunoglobulins
28
what secrete milk
secretory epithelium of the alveoli, larger ducts and gland cistern
29
The alveoli and ducts are surrounded by \_\_\_\_that contract to allow milk letdown to occur.
myoepithelial cells
30
31
isometric growth of the mammary gland
Increase in adipose tissue and supporting tissue
Independent of reproductive hormones
Occurs between birth and puberty
32
allometric growth of mammary gland
Increase in glandular tissue
Dependent on steroid hormones
**After puberty**
– **Prolactin and growth hormone** cause rapid duct development
**With each estrus cycle**
– **Estrogens** stimulate duct growth and branching
– **Progesterone** causes alveoli to form at the end of each duct
33
causes alveoli to form at the end of each duct
**Progesterone**
34
stimulate duct growth and branching
**Estrogens**
35
**\_\_\_ hormone** cause rapid duct development
**Prolactin and growth**
36
anterior pituitary mammary development
Regulation of ovarian hormones
Direct effect on prolactin and growth hormones
Indirectly by its control on ACTH and TSH
37
\_\_\_ hormones act directly on the mammary gland
**Estrogen-** duct growth and branching
**Progesterone-** formation of alveoli
**Placental lactogen-**
**Prolactin**
**Oxytocin-** parturition and contraction of uterus and endometrial role
38
throughout pregnancy estrogen stimulates the \_\_\_
ductile system
39
During the second half of gestation ___ acting with estrogen is responsible for full alveolar growth, which occurs rapidly
Progesterone
40
\_\_\_ progesterone concentrations inhibit final differentiation of the alveoli and prevent milk secretion during pregnancy.
high
41
\_\_\_ are metabolic hormones that directly effect the function of the mammary gland
**Growth Hormone**- effect metabolism
**Corticosteroids**- effect metabolism
**Thyroid hormone**
**Insulin-** glucose concentration
**GI Hormones**
42
local hormones for mammary glands
**prolactin**
**parathyroid hormone related peptide**
**leptin**
43
lactogenesis is inhibited by \_\_\_hormones
estrogen and progesterone
44
Drop in progesterone and estrogen at parturition allows release of \_\_\_
prolactin
45
\_\_\_ released at parturition stimulates release of prolactin
Oxytocin
46
prolactin activates what key signaling molecule?
STAT 5 → critical for lactation to take place
47
prolactin and growth hormone change the ___ mammary gland in to the ___ mammary land
proliferative
lactating
48
\_\_\_ is the maintenance of lactation
galactopoiesis
49
\_\_\_ is needed for galactopoiesis
(maintenance of lactation)
## Footnote
**Prolactin** is necessary
Growth hormone, insulin, ACTH, TSH play a role
**Regular suckling** stimulus maintains prolactin secretion
50
51
Sensory nerves of teats carry impulses to hypothalamic-pituitary axis results in release of \_\_\_
oxytocin
52
Oxytocin causes contraction of the ____ cells
myoepithelial
53
milk let down
Efficiently **evacuates alveol**i and small ducts
Systemic **reflex**
Sensory nerves of teats carry impulses to hypothalamic-pituitary axis results in **release of oxytocin**
Oxytocin causes c**ontraction of the myoepithelial cells**
Increases pressure within gland
54
FIL
(glycoprotein)(feedback inhibitor of lactation)
Produced in mammary epithelial cells
During milk stasis
Decreases secretory cell # & activity
Decreases prolactin receptors
Results in increase in secretory cell apoptosis
**Negative feedback** on milk & lactose synthesis
55
the mammary gland must be emptied regularly to remove \_\_\_
FIL
56
\_\_\_\_contains antibodies that have been sequestered from the dam’s blood by selective and active transport to the mammary gland during the last few weeks of pregnancy.
Colostrum
57
epitheliochorial
6 layers
no AB exchange
(horse, cattle, goats, pigs)
58
endotheliochorial
some AB exchange
4 layers
(dogs and cats)
59
haemochorial
AB exchange
(humans)
60
there is direct transfer of ___ from blood to milk
immunoglobulins
61
there is a modified transfer of ___ from blood to milk
glucose and fatty acids
62
there is a synthesis transfer of ___ from blood to milk
proteins and fats
63
lipids in milk are made of \_\_\_
triglycerides
From blood: phospholipids and cholesterol
fat in milk made in smooth ER by breaking down long chain fatty acids
64
Non-ruminants tend to use ___ in lipogenesis while ruminants use \_\_\_
glucose
acetate
65
During a single milking, the last portion of milk removed from the mammary gland is\_\_\_ than the first milk removed.
4 to 8 times higher in fat
66
lactose is formed by \_\_\_
glucose, lactic acid, pyruvate and hexose
67
hyoglycemia will increase or decrease the amount of lactose in the milk?
decrease
68
\_\_\_ increases the galactosyl transferase’s affinity to glucose 1000 X
alpha-lactalbumin
69
High concentrations of progesterone suppress ___ and inhibit milk secretion during pregnancy.
alpha-lactalbumin
70
3 types of protein in milk
**–Casein** –Lactoglobulin –Lactalbumin
71
most important mineral in milk is \_\_\_
calcium
72
\_\_\_ drains dam's calcium reserves
lactation
73
somatic cell count
measure of **milk quality**
cells located in the udder
\<2% epithelial cells
**most cells are leukocytes**
\<100,000 cell/ml milk - **no infection**
\>250,000 cells / ml milk - **infection**
74
involution (drying off)
75
involution
**Lactation length is variable**
**After peak lactation:**
– gradual decrease in active alveoli
– involution of epithelial tissue
– loss of secretory activity
– increase of connective tissue
**Hastened by:**
– decrease gland emptying
– estrogen
– bromocriptine
