Growing Beef

Question 1

lignin

Answer 1

component in plants that helps rigidity but decreases digestibility

Question 2

Result of too many non-structural carbohydrates?

Answer 2

rumen acidosis (but not enough also limited production)

Question 3

urea

Answer 3

common source of nitrogen for cattle, which can use it to create AA in the rumen

Question 4

How is energy calculated for ruminant diets?

Answer 4

from acidic and neutral detergent fibers

Question 5

What three types of energy are “remove” between gross energy and net energy?

Answer 5

1. indigestible (fecal loss)
2. digestible (urinary and gaseous (methane)) loss)
3. metabolizable (heat loss)

Question 6

How to feed a growing beef steer?

Answer 6

high protein, pound of feed to pound of gain, efficient growth

Question 7

HHow to feed a finishing steer?

Answer 7

high energy, ADG declininng, less efficient (eating more) but also less expensive than growing diet

Question 8

Consequences of acidosis on a feedlot?

Answer 8

change in intake pattern, liver abscesses, change in feed efficiency

Question 9

Measurable fiber content in ruminant diet?

Answer 9

Neutral edtergent fiber (NDF)

Question 10

What % NDF is required to maintain a normal rumen?

Answer 10

27%

Question 11

Goal of feedlot cattle?

Answer 11

sell a group of animals for more than total cost

Question 12

Cost of Gain Factors

Answer 12

ingredient cost, feed efficiency, digestibility, breed, cold or hot environment, etc

Question 13

Does the feed to gain ratio increase or decrease with weight gain?

Answer 13

decrease in that it takes more feed for the same gain (4:1 for smaller animals and 7:1 for bigger)

Question 14

What breed requires more for maintenance - Holsteins or Angus?

Answer 14

holsteins

Question 15

Less than 2 week old diet

Answer 15

milk, and only milk

Question 16

2 weeks to 3 months Diet

Answer 16

milk and grass

Question 17

4 to 7 months Diet

Answer 17

Grass and Milk, start grain

Question 18

7 to 10 Months Diet

Answer 18

Forage and Grain, begin 60:40 then finish this period 40:60

Question 19

10-14 Months Diet

Answer 19

Forage and Grain in 20:80 ratio

Question 20

2 Ways the Acid is managed in the Rumen

Answer 20

1. Absorb VFAs (sometimes exchanging with bicarbonate)
2. Chewing! Increases saliva which increases bicarbonate

Question 21

Does the rumen have a pH meter that communicates with the brain?

Answer 21

no! nothing tells the cow to chew more or anything like that

Question 22

What % of the acid produced is neutralized by saliva?

Answer 22

~50%

Question 23

Whattype of cattle spend the most time eating and ruminating - dairy cattle or feedlot cattle?

Answer 23

dairy cattle (produce twice as much saliva ~250L/day)

Question 24

Effect of Rumination Time on pH

Answer 24

increased time ruminating increases rumen pH

Question 25

Effect of Increased NDF on Rumination

Answer 25

Increased NDF results in increased ruminating

Question 26

Effect of Non-Structural Carbohydrates/Starch on Rumen pH

Answer 26

increased starch leads to decreased rumen pH (acidosis)