Dairy Cow Week 5 Study Questions

Question 1

What are the four major components of milk?

Answer 1

water, fat, protein, lactose

Question 2

What is the “Dairy Matrix”?

Answer 2

the physical structure of a dairy product, there is nutrients we understand and nutrients we do not know about. This is a product of the natural world and can not be made in the lab.

Question 3

Define homogenization

Answer 3

heat milk to 145 degrees F for 30 min to kill bacteria

Question 4

Define pasteurization

Answer 4

mechanical mixing so milk fat globs small and even

Question 5

Why is Vitamin D added to milk?

Answer 5

increase calcium absorption to prevent rickets

Question 6

What are the risks associated with drinking raw milk?

Answer 6

it is not pasteurized so it may contain dangerous bacteria

Question 7

What is a typical milk fat percentage for dairy cows?

Answer 7

3.9%

Question 8

Does the milk of a fur seal have more or less fat than the milk of a dairy cow?

Answer 8

MORE

Question 9

What are two types of milk proteins?

Answer 9

caseins and whey

Question 10

What is lactose?

Answer 10

milk sugar

Question 11

What are the main ingredients in dairy cow diets?

Answer 11

corn silage, alfalfa, grain, and protein supplements (TMR)

Question 12

What are the three layers of digesta inside the ruminant stomach?

Answer 12

gas, fiber mat, fluid pool

Question 13

What is rumination? What can rumination collars be used for?

Answer 13

-regurgitation of already chewed food
-collars can detect the amount of time a cow ruminates each day

Question 14

What role do bacteria, protozoa, and fungi play inside the rumen?

Answer 14

organisms in the rumen that assist with digestion

Question 15

What are the primary energy end products of digestion in the rumen?

Answer 15

VFA products, glucose, adipose, and protein

Question 16

Where does the methane produced in the rumen go?

Answer 16

in the rumen or in manure (atmosphere)

Question 17

Give some examples of what the dairy industry can do to reduce enteric methane production.

Answer 17

-Take manure from the cows and capture methane to sell
-Biogas generation from manure captures and uses methane that would have gone into the atmosphere otherwise

Question 18

What can the dairy industry do to reduce the amount of methane coming from manure?

Answer 18

DIET: Cow is making more acetate → producing more methane
-Feed substances/chemicals that kill off bacteria that produce methane
-Having efficient cows → having less cows
–>Get cows that make a lot of milk so you need less cows

Question 19

What are the molecular building blocks of milk?

Answer 19

water, fatty acids and glycerol, amino acids, and glucose

Question 20

What is the standard lactation length?

Answer 20

305 days

Question 21

When does peak lactation occur?

Answer 21

2 months

Question 22

What is persistency?

Answer 22

a consistent decline in milk production

Question 23

Are first lactation or fourth lactation cows more persistent?

Answer 23

first lactation

Question 24

What is negative energy balance?

Answer 24

energy expenditure exceeds intake

Question 25

What is Body Conditon Score (BCS)? What are the expectations for BCS loss and gain during lactation?

Answer 25

measures and monitors body condition --> lose some weight after calving but not too much

Question 25

What is Body Conditon Score (BCS)? What are the expectations for BCS loss and gain during lactation?

Answer 25

measures and monitors body condition --> lose some weight after calving but not too much

Question 26

What are the consequences of excessive weight loss for cows?

Answer 26

illness or disease --> ketosis or fatty liver

Question 27

What is a “transition cow”?

Answer 27

30 days prepartum to 30 days postpartum

Question 28

What are the two worst days in a cow’s life?

Answer 28

the day she calves and the day you dry her off

Question 29

What percentage of the herd will die on the farm each year? What period is the cow at the greatest risk?

Answer 29

5% --> first month of lactation

Question 30

What is milk fever? What are the symptoms of milk fever?

Answer 30

the cow lactates abruptly and drains calcium -- cow will become weak, fall down, and not get back up

Question 31

How is milk fever treated?

Answer 31

infuse calcium

Question 32

What is a “negative DCAD diet” and how does a negative DCAD diet prevent milk fever?

Answer 32

control the sensitivity to parathyroid hormone

Question 33

Why do cows get fatty liver postpartum?

Answer 33

cows lose weight postpartum and fat moves into the liver. The fat forms in the liver and she is unable to get it out.

Question 34

How do you prevent fatty liver postpartum?

Answer 34

diet, keep on weight postpartum

Question 35

What causes ketosis in the postpartum cow? What are some common symptoms of ketosis?

Answer 35

elevated BHB in the blood --> the cow feels sick and will not eat

Question 36

What are your options for testing a cow for ketosis?

Answer 36

test urine, blood, or milk

Question 37

How do you treat a cow with ketosis?

Answer 37

propylene glycol

Question 38

What is the difference between contagious and environmental mastitis pathogens?

Answer 38

contagious is transmitted during milking --> (passed from cow to cow) environmental is transmitted through the environment the cow is in --> (what they touch)

Question 39

How might you prevent contagious compared with environmental mastitis?

Answer 39

contagious: parlor hygiene, machine function, post dip. environmental: clean cow stalls, clean everything, udder prep both: dry cow treatment

Question 40

What is the difference between clinical and subclinical mastitis?

Answer 40

Clinical -- symptoms shown --> clotted milk, swollen udder, loss of appetite, fever Subclinical -- no symptoms shown

Question 41

How do you treat mastitis? Can you sell milk from antibiotic treated cows?

Answer 41

-antibiotics (DUMP MILK) -heal on her own -sell her

Question 42

What is milk somatic cell count (SCC) and what does it tell you about mammary infections?

Answer 42

SCC = come from the immune system to fight infection --> cows with mastitis will have high SCC in milk

Question 43

What is milk quality? How does SCC affect milk quality, taste and shelf life?

Answer 43

is the milk fresh, flavor, shelf life --> high SCC affects flavor and shelf life (worse and less)

Question 44

Are there antibiotic resistant bacteria on dairy farms?

Answer 44

YES

Question 45

What’s the best way to prevent antibiotic resistance on dairy farms?

Answer 45

use alternatives to antibiotics when possible

Question 46

What would be a typical incidence of fatty liver, milk fever, ketosis, and mastitis on farm?

Answer 46

-fatty liver (none) -milk fever (none) -ketosis (<10%) -mastitis (<2% of cows each month)

Question 47

Be able to define or explain VWP, days open, and calving interval.

Answer 47

-Voluntary Waiting Period (VWP) --> amount of time we wait to breed her -Days Open is the VWP and breeding time -The calving interval is the days open, through pregnancy, and dry off

Question 48

What is uterine involution? How long does it take for the uterus to completely restore normal fertility?

Answer 48

The uterus shrinking down to its normal size --> 60 days

Question 49

Name the diseases that affect the postpartum uterus.

Answer 49

retained placenta, metritis, endometritis, subclinical endometritis metritis --> endometritis --> SCE

Question 50

What causes metritis?

Answer 50

a uterine infection from environmental bacteria

Question 51

What type of surface is excellent for cows that are calving?

Answer 51

sand!! VERY CLEAN SAND

Question 52

How do you treat metritis? How do you treat endometritis or SCE?

Answer 52

Metritis: antibiotics Endometritis or SCE: NO treatments

Question 53

What is the difference between cyclic and anovular or anestrus cows?

Answer 53

cyclic --> the cow is cycling, going into estrus anovular/anestrus --> not cycling

Question 54

What are the two rules for getting cows pregnant?

Answer 54

rule 1: put semen in the cow rule 2: cow is not pregnant?.. refer to rule 1

Question 55

What are some methods of heat detection that could be used for postpartum cows?

Answer 55

Chalk or activity collar

Question 56

How can an activity or rumination collar be used for heat detection?

Answer 56

Activity increases when she is in heat

Question 57

What are timed AI (presynch ovsynch) programs?

Answer 57

give cows shots to line up ovulation

Question 58

What is early embryonic loss? What percentage of cows will have early embryonic loss?

Answer 58

expect 10% of pregnancies to be lost in the first 35-60 days

Question 59

When (approximate time relative to next calving) do you dry off a cow?

Answer 59

dry right before calving

Question 60

What are the three steps to dry off a cow?

Answer 60

-milk the cow -"selective" dry cow treatment (antibiotics) -Orbeseal (seal teat)

Question 61

What is “selective” dry cow therapy?

Answer 61

treat cows at dry off with an antibiotic

Question 62

How many lactations does a typical cow have before she is culled?

Answer 62

3