16. Dairy Cattle

Question 1

List 3 potential fates for male calves born on a dairy farm

Answer 1

1. ) Breeding
2. ) Beef
3. ) Veal

Question 2

Describe life cycle of a female calf born on a dairy farm

Answer 2

(Non-Seasonally polyestrous)

1. ) A heifer is bred at about 15 months in age, usually through artificial insemination.
2. ) About nine months later, she will give birth
3. ) The calf is fed her colostrum
4. ) when her lactation begins, the cow becomes part of the milking herd where she will produce milk for about 10 months

Question 3

What is a Heifer?

Answer 3

young female cow that has not borne a calf

Question 4

How much milk does a dairy cow produce a day?

Answer 4

about 27 litres of milk per day?

Question 5

At what percent of adult body weight and height can heifers begin to breed?

Answer 5

60-65% of body weight by 13-15 months of age

Question 6

Heifers would then calve for the first time at ____ months of age.

Answer 6

22 to 25 months of age

Question 7

Describe the cow estrous cycle and length of pregnancy.

Answer 7

1. ) length of pregnancy is 9 months
2. ) The normal non-pregnant cow enters estrus every 18-24 days unless cyclicity is interrupted by a pregnancy or pathology. Estrus lasts about 18 hours and ovulation occurs approximately 12 hours after the end of estrus.

Question 8

How did the Land Grant College system contribute to the modernization of dairy farming?

Answer 8

the grant (1862) gave universities acres of land in order to would EDUCATE PEOPLE IN AGRICULTURE, home economics, mechanical arts etc. This program is available to all people who are in search of higher education, no matter what social class.

Question 9

How did refrigeration contribute to the modernization of dairy farming?

Answer 9

Allowed trains to be packed with ice and sawdust and then pack dairy products to export

Question 10

How did pasteurization contribute to modernization of dairy farming?

Answer 10

Achieved through electricity which allowed Louis Pasteur to explore microbe work

Question 11

How did TB testing contribute to modernization of dairy farming?

Answer 11

Caused the cattle infection rate of TB to be <0.5% and allowed farmers to notice signs of TB

Question 12

How did the use of artificial insemination contribute to modernization of dairy farming?

Answer 12

It is now relied on by >66% of dairy cattle forms which allows more specific and safer breeding to occur

Question 13

How did cooperative testing associations contribute to modernization of dairy farming?

Answer 13

allowed groups of farmers to hire a tester who would give farmers data about their herd and how to benefit the

Question 14

Classify the cow estrous cycle

Answer 14

Non-seasonally polyestrous

Question 15

How long is cow pregnancy?

Answer 15

9 months

Question 16

At what age do calves freshen?

Answer 16

22 to 25 months

Question 17

List the top 5 dairy producing states (from highest to lowest)

Answer 17

1. California
2. Wisconsin
3. New York
4. Idaho
5. Pennsylvania

Question 18

Which breed of dairy cattle is dominant in the U.S.?

Answer 18

Holstein-Friesian

Question 19

Why is Holstein-Friesian the dominant dairy cattle breed in the U.S.?

Answer 19

It has the largest volume of milk production

Question 20

Which breed produces less milk (by volume) but produces the highest percentage of milkfat?

Answer 20

Jersey

Question 21

What is colostrum?

Answer 21

Initial milk containing more protein, fat, minerals and vitamins than milk produced later

Question 22

What is passive immunity?

Answer 22

A foal greater than 24 hours of age is considered to have failure of passive transfer if circulating antibody levels are less than 400 mg/dl

Question 23

What is freshening?

Answer 23

When a cow can produce milk

Question 24

What is drying off?

Answer 24

Approximately 45 to 60 days prior to calving, cows are removed from the milking herd to allow for the completion of calf development and for repair and regeneration of udder tissue

Question 25

What is total mixed ration (TMR)?

Answer 25

a method of feeding cows that combines all forages, grains, protein feeds, minerals, vitamins and feed additives formulated to a specified nutrient concentration into a single feed mix

Question 26

List the components of milk

Answer 26

87-88% water
12-13% Solids
(8.6% solids-non-fat, 3-4% milk fat and minerals)

Question 27

Summarize current trends in the U.S. dairy industry

Answer 27

There are fewer cows than in history, but more milk is being produced

Question 28

Summarize the “testing” of milk

Answer 28

Safety:
1.) Temp
2.) Antibiotics
3.) somatic cell count
4.) bacterial count
Quality:
1.) % milk fat
2.) % protein
3.) milk Urea Nitrogen

Question 29

Summarize the “processing” of milk

Answer 29

1. ) Separation
2. ) Standardization
3. ) Fortification
4. ) Pasteurization
5. ) Homogenization
6. ) Rapid cooling

Question 30

Be able to Draw a lactation curve and label the axes. Explain each sage of milk production on the curve relative to reproduction (calving, breeding, drying off, calving interva)

Answer 30

be able to draw the curve