Lecture 21: Beef Nutrition 1 (Exam 2)

Question 1

What are the three types of beef cattle operations

Answer 1

• Cow-calf
• Background & stocker
• Finishing operations

Question 2

Describe cow calf operations

Answer 2

• Can be large, med, or small
• 3/4 raise commercial cattle to be marketed for consumption

Question 3

What is the goal of background stocker operations

Answer 3

To grow feeder cattle to a weight for entering the feedlot (~ 700 to 800 lbs)

Question 4

Describe backgrounding

Answer 4

Weaned calves kept on dry lot & fed roughage & grain

Question 5

Describe stocker

Answer 5

Weaned calves grazing pasture w/ some grain supplementations

Question 6

What is the goal of finishing operations

Answer 6

Grow to finished wt for slaughter

Question 7

What % of beef cattle operations are small scale farmers

Answer 7

90%

Question 8

Where do ~2/3 of calves from cow calf operations sold to after weaning

Answer 8

“Feeder” calves go to backgrounding or stocker operations

Question 9

What are the goals of cow calf operations

Answer 9

• Maintain repro efficiency
• Min calf morbidity & mortality
• Keep cows cheaply over the winter
• Market a calf that somebody wants to buy
• Overall goal is to max # of calves sold

Question 10

What are the average beef cattle weights for mature angus cow, newborn calf, weaning weight, stocker cattle, & finished weight

Answer 10

Question 11

What are the production goals of a beef herd

Answer 11

• Have a calf crop > 90%
• Cows have 1 calf per year
• Have 80% of cows in heat by 60 days post calving
• The calves weaning weight to be 45 to 50% of the cows weight
• Want less than 5% of cows have dystocia

Question 12

What is the calving interval for beef cows

Answer 12

365 days

Question 13

What is the length of breeding season in cows

Answer 13

65 days

Question 14

When do cows resume the estrus cycles

Answer 14

40 to 60 days post calving

Question 15

When should cows become pregnant to maintain the yearly calving interval

Answer 15

80 days post calving

Question 16

What is the length of the breeding season

Answer 16

65 days

Question 17

What is the average age of calves @ weaning

Answer 17

180 days (6 months)

Question 18

What type of cattle are used in backgrounding & stockers

Answer 18

Newly weaned calves not ready for the feedlot

Question 19

What is metabolizable protein

Answer 19

Microbial protein + UIP

Question 20

Which is higher in Ca forage or grains

Answer 20

Forage

Question 21

Why is the Ca:P important in steers

Answer 21

B/c of the dev of urinary calculi

Question 22

When is sulfur needed

Answer 22

When urea is added to decrease the toxicity concern

Question 23

What are the vitamin req of beef cattle

Answer 23

• Vitamin A,D, & E
• Usually don’t have to add B vitamins & vitamin K to diets b/c microbes synthesize it

Question 24

What is req for milk production & growth

Answer 24

• Calcium
• Phosphorus

Question 25

Describe phosphorus & calcium in grains & corn

Answer 25

* Higher in P * Lower in Ca

Question 26

What are the major minerals of beef cattle

Answer 26

* Magnesium (can be low in lush spring grass) * Salt (Most feeds are low in sodium) * Potassium (High in forages & low in grains) * Sulfur

Question 27

What trace minerals should be part of an adeq mineral supplementation program

Answer 27

* Co * Cu * I * Mn * Se * Zn

Question 28

When should nutrient req be adjusted for cows

Answer 28

* Stage of production * Environmental adjustments * Cow size & breed * BCS