Exam 1

Question 1

What are the 4 major digestive processes?

Answer 1

Mechanical, chemical, enzymatic, and fermentative

Question 2

How many grams in a pound?

Answer 2

454

Question 3

How many pounds in a kg?

Answer 3

2.2

Question 4

How much is a bushel?

Answer 4

56lb

Question 5

How do we classify animals digestively?

Answer 5

Based on where fermentation occurs

Question 6

Ruminant

Answer 6

Complex

Question 7

Monogastric

Answer 7

Simple

Question 8

Functions in GIT: Mouth

Answer 8

Primarily mechanical, some enzymatic, prehension of food, start digestion, and taste

Question 9

Functions in GIT: Saliva

Answer 9

Lubrication, buffer, nutrients from rumen microbes, prevention of rumen frothing, protection of mouth

Question 10

What taste receptors do cats not have?

Answer 10

T1R2 - Sweet

Question 11

Composition of Saliva

Answer 11

water, mucin, bicarbonate salts/ electrolytes, enzymes in some species

Question 12

Functions in GIT: Stomach

Answer 12

Mechanical, chemical, and enzymatic digestion, feed storage, reduce particle size of feed, mucous secretion, low pH kills bacteria and activates enzymes

Question 13

What is the hunger hormone?

Answer 13

ghrelin

Question 14

Functions in GIT: Small Intestine

Answer 14

Mechanical and enzymatic digestion and absorption of nutrients

Question 15

Where does bile enter GIT

Answer 15

duodenum

Question 16

Where does bile go after digestion?

Answer 16

98% recycled back to liver

Question 17

Pancreatic secretions?

Answer 17

Digestive enzymes and bicarbonate

Question 18

Brush boarder enzymes?

Answer 18

Sucrase, maltase, lactase, aminopeptidases, dipeptidases

Question 19

Functions in GIT: Large Intestine

Answer 19

Mechanical and fermentative digestion, water and mineral absorption, fiber digestion in nonruminants, synthesis of vitamins B&K, production of VFAs for enterocytes

Question 20

Avian Differences?

Answer 20

No teeth or amylase, crop for feed storage, proventriculus acts as stomach, ventriculus grinds feed, ceca, cloaca

Question 21

Ruminant differences?

Answer 21

No enzymatic digestion in mouth, saliva recycling of N Na P and H2O

Question 21

Ruminant SI

Answer 21

no sucrase

Question 21

Site of fermentation in Ruminants?

Answer 21

rumen, reticulum, and omasum

Question 21

Primary loss of water

Answer 21

In urine and feces

Question 21

6 Major classes of nutrients?

Answer 21

Water, protein, fats, carbohydrates, vitamins, minerals

Question 22

"true" stomach of rumen?

Answer 22

abomasum

Question 23

Standard Proximate Analysis System?

Answer 23

Weende system

Question 24

Weende system

Answer 24

water, protein, fat, total minerals, and some carbohydrates

Question 25

Detergent Analysis System?

Answer 25

Van Soest system

Question 26

Ash

Answer 26

Minerals -inorganic

Question 27

Nitrogen-free extract

Answer 27

estimate of digestible carbohydrates NOT determined via laboratory analysis - it is calculated

Question 28

How is dry matter measured?

Answer 28

heating the sample in a drying oven until there is no change in weight - typically takes 1-5 days

Question 29

Is moisture on feed labels?

Answer 29

Yes

Question 30

Why does nutrient ratio increase when going from as-fed to dry matter?

Answer 30

Water dilutes the nutrients we care about

Question 31

Organic matter % =

Answer 31

100% - Ash %

Question 32

Where is material oxidized to measure ash?

Answer 32

Muffle furnace

Question 33

What might high ash indicate?

Answer 33

soil contamination

Question 34

Problems with measuring ash?

Answer 34

No indication of individual minerals & some minerals are lost

Question 35

Methods to measure nitrogen precent?

Answer 35

Kjeldahl and LECO

Question 36

Crude Protein % =

Answer 36

% Nitrogen * 6.25

Question 37

Why is 6.25 the N conversion factor?

Answer 37

(on average) proteins contain 16% nitrogen

Question 38

Non-Protein Nitrogen

Answer 38

Free amino acids can be used to meet AA requirements of nonruminants and protein requirements of ruminants

Question 39

Problems with CP

Answer 39

No indication of protein quality, only measures N not the source, and no indication of digestibility or rumen degradability

Question 40

What animals should eat RUP/bypass protein?

Answer 40

fast-growing feedlot animals & high high-producing dairy animals

Question 41

Problems with ether extract?

Answer 41

EE consists of true lipids and other ether-soluble compounds like fat-soluble vitamins, waxes, chlorophyll etc.

Question 42

Crude Fiber:

Answer 42

not accurate but theoretically represents structural carbohydrates

Question 43

Nitrogen-Free Extract represents

Answer 43

Starch, sugar, and digestible carbohydrates - typically overestimated

Question 44

Most digestible structural carbohydrate? Least?

Answer 44

Most: Cellulose Least: Lignin

Question 45

NDF

Answer 45

cell wall components cellulose, hemicellulose, lignin highly related to feed intake/gut fill

Question 46

ADF

Answer 46

cellulose and lignin highly related to feed digestibility

Question 47

TDF

Answer 47

Most accurate way to get true fiber Used in human food industry but not widely used in animal feed industries Very labor intensive and expensive

Question 48

Heat damage

Answer 48

referred to as Maillard or Browning reaction - reduces digestibility

Question 49

Heat damage is determined by?

Answer 49

Acid Detergent Insoluble Nitrogen Determine nitrogen attached to the ADF residue