ANIMAL SCIENCE 320
Instructors
Dr. Cheryl L. Morris
201D Kildee Hall
clmorris@iastate.edu
Dr. Jim Russell
313 Kildee Hall
jrussell@iastate.edu
Graduate TA:
Olivia Genther
333 Kildee Hall
genthero@iastate.edu
Mondays 2:00 – 4:00 PM
Graduate TA:
Matt O’Neil
337C Kildee Hall
maoneil@iastate.edu
Tuesdays 2:00 – 4:00 PM
Meeting Times and Locations
Monday and Wednesday Lectures:
8:00 – 8:50 AM
Kildee 108
Wednesday Labs:
2:10 – 4:00 PM
Kildee 25
Computer Lab Dates (Room 1):
April 3
April 15
April 24
April 29
April 17
May 1
April 22
Text
Animal Feeding and Nutrition, 11th Edition, Jurgens,
Bregendahl, Coverdale, Hansen
SCHEDULE
Date
1/14
Lecture/Lab
Lecture
Topic
Introduction. Reviewing nutrient digestion in nonruminant and ruminant
animals
Chemical analysis of feedstuffs
Instructor
C.Morris
1/16
Lecture
1/16
Lab
Calculating the composition of feedstuffs and diets
C.Morris
1/21
No Class
Martin Luther King Day
1/23
Lecture
Determining the digestibility of feedstuffs
C. Morris
1/23
Lab
C. Morris
1/28
Lecture
Energy systems for feedstuffs and applications for calculating feed intake or
animal production
Energy feedstuffs
1/30
Lecture
Energy Supplements
J. Russell
1/30
Lab
Quiz 1. Feedstuff identification
J. Russell
2/4
Lecture
Protein supplements
J. Russell
2/6
Lecture
By-product feedstuffs
J. Russell
2/6
Lab
Basic Ration Formulation
J. Russell
2/11
Lecture
Forage species and quality
J. Russell
2/13
Lecture
Grazing systems
J. Russell
2/13
Lab
2/18
Lecture
Harvested forages (Hay)
J Russell
2/20
Lecture
Harvested forages (Silages)
J Russell
2/20
Lab
Multiple Ingredient Ration Formulation
J Russell
2/25
Lecture
Mineral and vitamin supplements
C. Morris
2/27
Lecture
Feed additives
C. Morris
2/27
Lab
Formulating premixes
C. Morris
C.Morris
J. Russell
Exam 1
SCHEDULE
Date
3/4
Lecture/Lab
Lecture
Topic
Feed processing and mixing
Instructor
C. Morris
3/6
Lecture
Feed processing and mixing
C. Morris
3/6
3/11
Lab
Lecture
Quiz 2. Interpreting feed tags and regulations
Companion Animals
C. Morris
C. Morris
3/13
Lecture
Companion Animals
C. Morris
3/13
Lab
Companion Animals
C. Morris
3/25
Lecture
Poultry
M. Persia
3/27
Lecture
Poultry
M. Persia
3/27
Lab
Poultry
M. Persia
4/1
Lecture
Horses
C. Morris
4/3
Lecture
Horses
C. Morris
4/3
Lab
Exam 2
C. Morris
4/8
Lecture
Swine
J. Patience
4/10
Lecture
Swine
J. Patience
4/10
Lab
Swine
J. Patience
4/15
Lecture
Beef Cattle
J. Russell
4/17
Lecture
Beef Cattle
J. Russell
4/17
Lab
Beef Cattle
J. Russell
4/22
Lecture
Dairy Cattle
J. Russell
4/24
Lecture
Dairy Cattle
J.Russell
4/24
Lab
Quiz 3 & Dairy Cattle
J. Russell
4/29
Lecture
Small Ruminants (Goats/Sheep)
D. Morrical
SCHEDULE
Date
5/1
Lecture/Lab
Lecture
5/1
Lab
Topic
Small Ruminants (Goats/Sheep)
Exotics
Final Exam (Exam #3)
Instructor
D. Morrical
C. Morris
EVALUATION AND GRADE SCALE
Grading:
Item
Number
Points each
Total points
Problem sets
12
25
300
Quizzes
3
33.3
100
Exams
3
100
300
-100
-100
Drop lowest total quiz or exam score
Total
Grades
600
%
A
93-100
A-
90-93
B+
87-90
B
83-87
B-
80-83
C+
77-80
C
73-77
C-
70-73
D+
67-70
D
63-67
D-
60-63
F
<60
Reviewing Nutrient Digestion
• Chapter 1
– Review of Nutrients Pp. 3 - 63
– Review of Digestion Pp. 63 – 77
• Non Ruminant
• Ruminant
Types of Digestion
Mechanical
Chemical
Enzymatic
Fermentative
DIGESTIVE SYSTEMS REVIEW
Non-ruminant Digestive Tract
FUNCTIONS OF PARTS OF THE
NONRUMINANT DIGESTIVE TRACT
• Mouth
– Prehension and mastication
– Taste
– Secretion of saliva
• Composition
–
–
–
–
Water
Mucin
Bicarbonate salts
Enzymes (some species)
• Stomach
– Secretions
• Hydrochloric acid
• Protease
– Pepsinogen → Pepsin
• Hormone
– Gastrin
• Small intestine (2 main functions)
– Secretions (From 3 locations)
1. Pancreas
– Proteases
» Trypsinogen → Trypsin
» Chymotrypsinogen → Chymotrypsin
» Procarboxypeptidase → Carboxypeptidase
– Carbohydrase
» Amylase
– Lipase
» Lipase
2. Liver
– Bile salts
3. Intestinal mucosa
– Carbohydrases
» Maltase
» Lactase
» Sucrase
– Peptidases
– Gut hormones
» Secretin
» Cholecystokinin
– Absorption
• Large intestine
– Structural carbohydrate fermentation
• Importance and size dependent on diet
• What is a structural carbohydrate that might be
fermented in the large intestine vs. a carbohydrate that is
not structural or fermented in the large intestine?
– Example?
REVIEW OF NONRUMINANT DIGESTION
Nutrient
Mouth
Starch
Amylase
initiates
digestion to
maltose
Disaccharides
Structural
carbohydrates
Stomach
Small intestine
Large
intestine
Pancreatic amylase &
intestinal maltase to
glucose
Intestinal
disaccharidases to
monosacharides
Fermented
to:
Volatile
Fatty Acids
(VFA’s)
REVIEW OF NONRUMINANT DIGESTION
Nutrient
Protein
Mouth
Stomach
Small intestine
HCL and
pepsin
Proteases (pancreas)
dipeptidases
(intestine)
peptides
Large intestine
Amino acids
Lipids (Including
fat-soluble
vitamins)
Bile salts & pancreatic
lipase to
monoglycerides, fatty
acids, and fat-soluble
vitamins
Water soluble
vitamins
Absorption
Produced
during
fermentation
AVIAN DIGESTIVE TRACT
DIFFERENCES BETWEEN AVIAN AND
NONRUMINANT MAMMALIAN DIGESTIVE TRACTS
• Mouth
– Prehension of feed
– No teeth
– No amylase
• Esophagus
– Has crop for feed storage
• Stomach
– Proventriculus before feed is ground
• Gizzard (Ventriculus)
– Grinds feed
• Small intestine
– No lactase
• Large intestine (Ceca)
– Small in most species
• Cloaca
– Organ where feces mixed with urinary waste products
RUMINANT DIGESTIVE TRACT
FUNCTIONS OF PARTS OF THE RUMINANT
DIGESTIVE TRACT
• Mouth
– Prehension of feed
• Lips and tongue
– Chewing
• Eating and Rumination
– Taste
• Avoidance
– Secretion of saliva
• Secretion of buffers
– NaHCO3 and NaH2PO4
– Maintain rumen pH
• Recycling of N, Na, P, and water to rumen
• Bloat prevention
• Esophagus
– Involved in rumination and eructation
• Stomach
– Reticulum, rumen & omasum
• Fermentation
• Absorption of fermentation endproducts
– Abomasum
• Secretion of hydrochloric acid and pepsinogen
• Small intestine
– Similar to non-ruminant
– No sucrase
• Large intestine
– Similar to non-ruminant
– More important in browsing species
CARBOHYDRATE DIGESTION IN RUMINANTS
Starch
Structural CHO
Methane
Undegraded
Fermented
Volatile fatty acids (VFA)
Liver & peripheral tissues
Energy and fat synthesis
Small intestine
(Digestion similar to NR)
PROTEIN DIGESTION IN RUMINANTS
True protein
NPN
Undegraded
Small intestine
Metabolizable
protein
Degraded
Recycled via
saliva
(20% of dietary N)
NH3
Microbial
protein
NH3
Liver
Urea
Kidney
Excreted
LIPID DIGESTION IN RUMINANTS
Fat
Undegraded
Degraded
Glycerol
VFA Long chain FA
Liver & peripheral tissues
Energy and fat synthesis
Saturated FA
Small intestine
(Digestion similar to NR)
What is the primary volatile fatty acid
produced in the rumen fed a high
forage diet?
1.
2.
3.
4.
5.
Acetic acid
Butyric acid
Lactic acid
Conjugated linoleic acid
Propionic acid