Dairy Cow Week 4 Study Questions

Question 1

What is the difference between stroma and parenchyma in the mammary gland?

Answer 1

stroma: supportive connective tissue
parenchyma: glandular secretory tissue

Question 2

describe the aveoli and ducts including important cell types

Answer 2

aveoli = milk secreting epithelial cells
A spherical shape with epithelial cells around the inside. Myoepithelial cells cover the outside with the capillaries. This is connected to the duct.
–> myoepithelial cells and epithelial cells

Question 3

myoepitheial cells

Answer 3

MYO=muscle (contract)
–> cells contract is response to oxytocin

Question 4

epithelial cells

Answer 4

make milk and secrete into lumen

Question 5

What is mammogenesis?

Answer 5

development of the mammary gland

Question 6

describe the hormones and structures involved in mammogenesis

Answer 6

hormones: progesterone and estradiol
–>ducts
hormone: prolactin
–>aveoli

Question 7

timing of duct and aveoli formation

Answer 7

1-2 months before calving

Question 8

Where do the antibodies in the colostrum come from?

Answer 8

transferred from maternal serum to colostrum into mammary gland

Question 9

When is colostrum formed and what two hormones are responsible?

Answer 9

4-6 weeks prepartum
–>estrogen and progesterone

Question 10

Why do we vaccinate the mother to protect the calf?

Answer 10

because the antibodies will go to the calf

Question 11

What hormones terminate colostrogenesis?

Answer 11

glucocorticoids and prolactin

Question 12

What is lactogenesis?

Answer 12

initiation of lactation

Question 13

describe the hormone cascade during late pregnancy that leads to lactogenesis

Answer 13

release of CRH –> release of ACTH –> release of glucocorticoids –> placenta converts progesterone to estradiol –> induces mother to make prolactin

prolactin and glucocorticoids initiate the production of milk

Question 14

describe the hormone and receptor cascade that leads to calving

Answer 14

progesterone decreases in the myometrium and can express oxytocin receptors

Question 15

describe the “neuroendocrine loop” that leads to milk let down

Answer 15

Nerve impulses from the teat: Washing the teat or nursing of the calf
Brain: oxytocin release in blood
–> milk let down

Question 16

How long does it take to milk a cow?

Answer 16

10 minutes

Question 17

What is a “parlor turn”?

Answer 17

time it takes to get a group of cows in and out of the parlor

Question 18

describe or diagram a parallel parlor, herringbone parlor, and rotary parlor

Answer 18

-parallel = cows parallel to each other
-herringbone = diagonal stalls
-rotary = circular parlor

Question 19

What is the difference between a monobox and rotary robotic parlor?

Answer 19

-monobox = one cow at a time
-rotary = multiple cows at once

Question 20

What might be an advantage of a robot milker? What is a disadvantage of a robot milker?

Answer 20

less labor and cows enjoy being milked by robots.
–robot milkers are expensive–

Question 21

What are the steps for prepping a cow to be milked?

Answer 21

pre-dip, strip, post-dip

Question 22

Understand how a milking machine works

Answer 22

a vacuum suction that has milk and rest periods.
–> milk out=gland cistern emptied
–>rest=refill gland

Question 23

What is an “automatic take off”?

Answer 23

A chain on the milking unit that removes it once the cow has finished milking

Question 24

What the purpose of the “post-dip” (applied after milking)?

Answer 24

sanitize and seal the teat

Question 25

Why would you milk 3x versus 2x daily?

Answer 25

increases milk yield by 10%

Question 26

What is a milk cooperative?

Answer 26

make sure the farmer has a good price and a place to sell the milk

Question 27

What is a continuous versus seasonal calving herd?

Answer 27

continuous: cows calve year round
seasonal: calve in springtime

Question 28

What is the relationship between grass growth and milk production in a seasonal calving herd?

Answer 28

Cows lactate during the spring and summer when there is grass available for them to graze on

Question 29

When do you breed cows in a seasonal calving herd?

Answer 29

May (about 2 months after calving in March)

Question 30

When do you dry off cows?

Answer 30

60 days before calving