INTRODUCTION TO ANIMAL
SCIENCE 320
COURSE OUTCOMES
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14.
Identify and explain methods of laboratory analysis of feed nutrients.
Identify and explain in vivo methods for the measurement of the nutritional value of
feedstuffs.
Assemble and interpret feed composition measurements from laboratory analyses,
NRC publications, or scientific literature to be used in diet formulation and problemsolving.
Interpret commercial feed labels.
Identify the nutritional and physical characteristics and production of available
feedstuffs used in livestock, poultry and companion animal diets.
Identify feeds by both gross and microscopic techniques
Recall and evaluate the suitability and limitations of specific feedstuffs in the
preparation of diets for different species and production classes of animals.
Identify the effects of cropping, harvest, storage, and processing practices on the
nutritional and physical characteristics of feedstuffs.
Use manual calculation techniques to balance rations for animals.
Understand and use computer ration balancing software for specific classes of
animals.
Evaluate diets for nutritional adequacy and practicality within the limitations of
preparation, transport, storage, feeding, and economic feasibility.
Understand the mechanisms of action and appropriate use of feed additives and
implants in animal feeding programs.
Develop feeding systems appropriate for different animal classes entering different
phases of production or life.
Understand and evaluate diet mixing and delivery systems.
SCHEDULE
Date
1/9
Lecture/Lab
Lecture 1
1/9
Lecture 2
1/11
Lab
1/18
Topic
Introduction. Reviewing nutrient digestion in nonruminant and ruminant
animals
Instructor
J Russell
Chemical analysis of feedstuffs
J Russell
Calculating the composition of feedstuffs and diets
J Russell
Lecture 1
Determining the digestibility of feedstuffs
J Russell
1/18
Lecture 2
Energy systems for feedstuffs
J Russell
1/18
Lab
Use of energy systems for calculating feed intake or animal production
J Russell
1/23
Lecture 1
Energy feedstuffs
L Baumgard
1/23
Lecture 2
Protein supplements
L Baumgard
1/25
Lab
Quiz 1. Feedstuff identification
L Baumgard
1/30
Lecture 1
Protein supplements
L Baumgard
1/30
Lecture 2
By-product feedstuffs
L Baumgard
2/1
Lab
2/6
Lecture 1
Forage species and quality
J Russell
2/6
Lecture 2
Grazing systems
J Russell
2/8
Lab
Calculating feed inventories
J Russell
2/13
Lecture 1
Harvested forages (Hay)
J Russell
2/13
Lecture 2
Harvested forages (Silages)
J Russell
2/15
Lab
Quiz 2. Basic ration formulation methods
J Russell
2/20
Lecture 1
Mineral and vitamin supplements
L Baumgard
2/20
Lecture 2
Feed processing and mixing
L Baumgard
2/22
Lab
Formulating premixes
L Baumgard
2/27
Lecture 1
Feed additives
L Baumgard
2/27
Lecture 2
Interpreting feed tags
L Baumgard
2/29
Lab
Exam 1
Exam 2
3/5
Lecture 1
Feeding companion animals (Dogs)
L Baumgard
3/5
Lecture 2
Feeding companion animals (Cats)
L Baumgard
3/7
Lab
Diet preparation for Dogs and Cats
L Baumgard
3/19
Lecture 1
Feeding beef cattle (Breeding herd)
J Russell
3/19
Lecture 2
Feeding beef cattle (Growing-finishing cattle)
J Russell
3/21
Lab
Balancing rations for beef cattle (Beef Brands)
J Russell
3/26
Lecture 1
Feeding swine (Breeding herd)
J Patience
3/26
Lecture 2
Feeding swine (Growing-finishing pigs)
J Patience
3/28
Lab
Quiz 3. Balancing rations for swine (National Swine Nutrition Guide)
J Patience
4/2
Lecture 1
Feeding calves
L Baumgard
4/2
Lecture 2
Feeding developing heifers
L Baumgard
4/4
Lab
4/9
Lecture 1
Feeding dairy cattle (Lactating herd)
L Baumgard
4/9
Lecture 2
Feeding dairy cattle (Dry and transition cattle)
L Baumgard
4/11
Lab
Balancing rations for dairy cattle (CNCPS)
L Baumgard
4/16
Lecture 1
Feeding Poultry (Layers)
M Persia
4/16
Lecture 2
Feeding Poultry (Meat birds)
M Persia
4/18
Lab
Quiz 4. Balancing rations for poultry
M Persia
4/23
Lecture 1
Feeding sheep
D Morrical
4/23
Lecture 2
Feeding horse
P Miller-Auwerda
4/25
Lab
Final
Exam
Exam 3
Balancing rations for sheep/ horses (Sheep & Horse Brands
Exam 4
D Morrical/P.
Miller-Auwerda
EVALUATION AND GRADE SCALE
Item
Number
Points each
Total points
Problem sets
12
25
300
Quizzes
4
25
100
Exams
4
100
400
-100
-100
Drop lowest total quiz or exam score (No make-up
quizzes or exams will be given)
Total
Grades
700
%
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
DIGESTIVE SYSTEMS REVIEW
Pages 68-82
Nonruminant Digestive Tract
FUNCTIONS OF PARTS OF THE
NONRUMINANT DIGESTIVE TRACT
• Mouth
– Chewing
– Taste
– Secretion of saliva
• Amylase?
• Stomach
– Secretions
• Hydrochloric acid
• Protease
– Pepsinogen → Pepsin
• Hormone
– Gastrin
• Small intestine
– Secretions
• Pancreas
– Proteases
» Trypsinogen → Trypsin
» Chymotrypsinogen → Chymotrypsin
» Procarboxypeptidase → Carboxypeptidase
– Carbohydrase
» Amylase
– Lipase
» Lipase
• Liver
– Bile salts
• Intestinal mucosa
– Carbohydrases
» Maltase
» Lactase
» Sucrase
– Peptidases
– Gut hormones
» Secretin
» Cholecystokinin
– Absorption
• Large intestine
– Structural carbohydrate fermentation
REVIEW OF NUTRIENT DIGESTION IN NONRUMINANTS
Nutrient
Mouth
Starch
Amylase
initiates
digestion
to maltase
Disacharides
Structural
carbohydrates
Stomach
Small intestine
Large
intestine
Pancreatic
amylase &
intestinal
maltase to
glucose
Intestinal
disacharidases
to
monosacharides
Fermented
to volatile
fatty acids
REVIEW OF NUTRIENT DIGESTION IN NONRUMINANTS
Nutrient
Protein
Mouth
Stomach
Small intestine
HCL and
pepsin
initiates
digestion
to
peptides
Pancreatic
proteases &
intestinal
dipeptidases
to amino acids
Lipids
(Including fatsoluble
vitamins)
Bile salts &
pancreatic
lipase to
monoglycerides,
fatty acids, and
fat-soluble
vitamins
Water soluble
vitamins
Absorption
Large
intestine
Produced
during
fermentation
SIGNIFICANCE OF NONRUMINANT DIGESTION
• Endproducts of nonruminant digestion are
the simple nutrients derived directly from the
complex nutrients in the diet
– Implications
• Nonruminant nutrient requirements must be met directly
from the diet
– Essential Amino acids
» Phenylalanine
» Valine
» Tryptophan
» Threonine
» Isoleucine
» Methionine
» Histidine
» Arginine
» Leucine
» Lysine
• Nutrient composition of nonruminant animal products
resemble the nutrient composition of the diet
AVIAN DIGESTIVE TRACT
DIFFERENCES BETWEEN AVIAN AND
NONRUMINANT MAMMALIAN DIGESTIVE TRACTS
• Mouth
– No teeth
– No amylase
• Esophagus
– Has crop for feed storage
• Stomach
– Proventriculus before feed is ground
• Gizzard (Venticulus)
– Grinds feed
• Small intestine
– No lactase
• Large intestine
– 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 nonruminant
– No sucrase
• Large intestine
– Similar to nonruminant
– 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)
SIGNIFICANCE OF RUMINANT DIGESTION
• Greater digestion of plant fiber than nonruminants
• Major endproducts of carbohydrates are the VFAs
– High forage diets→More acetate (C2)→More milk fat
– High grain diets→More propionate (C3)→Greater body weight
• Low amounts of glucose absorbed
– High producing dairy cows subject to ketosis
• Protein requirement is primarily met by rumen
degradable N
– Rumen undegradable protein needed by high producing dairy
cows or growing cattle
– No requirement for essential amino acids
• Ruminant animal products (meat and milk) contain high
concentrations of saturated fatty acids (and CLA)