Effect of harvesting systems and wilting on bermudagrass nutrient recovery and nutrient utilization by beef cattle

235 Pages·1991·6.8 MB·English

by  Berthe, Abou, 1949-

EFFECT OF HARVESTING SYSTEMS AND WILTING ON
BERMUDAGRASS NUTRIENT RECOVERY AND NUTRIENT
UTILIZATION BY BEEF CATTLE
BY
ABOU BERTHE
A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL
FULFILLMENT OF THE REQUIREMENTS FOR
THE DEGREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
1991
DEDICATION
To the memory of my father, El Hadji Hamidou Berthe, may god bless
him and grant him peace.
To the memories of my beloved grandmother and Aunt, Bintou
Coulibaly, Tenin Keita whose affection and guidance have given me
determination to strive for progress.
To my mother Sanata Keita who showed me early the values of
knowledge.
To my dear wife, Oumou Sidibe, whose support, dedication,
patience and endurance has made possible the successful
achievement of our Goal.
To my children, Abdramane, Bintou, Seydou, Hamidou, Ibrahim
and Kadidia-- The future is yours!
ACKNOWLEDGMENTS
The complex nature of a beef/forage system analysis required
collaboration and coordination from various people. Drs. William E.
Kunkle and Douglas B. Bates served as chair and cochair, respectively,
and are to be commended for their aid in organizing the project and for
editing the manuscript. Their guidance and constructive criticism are
appreciated. To Professors John E. Moore, Charles Staples and Thomas
Spreen, a message of gratitude is conveyed for their able and willing
participation. Special thanks are expressed to Dr. George E. Combs,
graduate coordinator, for the time he devoted to me during my program.
A note of thanks is extended to Angelita Mariano, Jeanette Filer,
William Schwingel and Tadd Dawson for their support. The friendship and
support offered by Dr. Sandra Russo, John Lichte, Dr. Della McMillan,
Dr. Ester Smith and many people not cited here are greatly appreciated.
I am also thankful to Jerry Wasdin and his team at Pines Acres for
all help in harvesting, storing and feeding the forages used in these
experiments. The friendship and humor of Sandy, Dan and Tom made the
social environment more tolerable.
The financial support of my program was provided by
IER/USAID/SECID. The initial assistance of Dr. Thomas Fretz as training
coordinator is appreciated. I am thankful to Dr. Irma Silva-Barbeau and
Dr. Ruth Niles for their supports as training coordinator for the
project IER/USAID Mali.
I am especially indebted to a group of individuals whose
collaboration and help have certainly shaped the path of my life; the
friendship of Dr. Tiomoko Traore, the teaching and support of Dr. N'Golo
Traore, Dr. Abou Bagayoko, Ir. Mamadou Fatogoma Traore and Dr. J.H.
Teissier are inestimable.
TV
TABLE OF CONTENTS
Page
ACKNOWLEDGMENTS iii
LIST OF TABLES viii
LIST OF FIGURES xiii
ABSTRACT xiv
CHAPTERS
I INTRODUCTION 1
II LITERATURE REVIEW 3
Dry Matter Production of Tropical Grasses 4
Conservation of Warm-Season Grasses 6
Silage-Making Systems 9
Additive-based silage
systems 13
Wilted silage systems 17
Nutrient Losses During Harvesting 19
Respiration Losses 19
Mechanical Losses 28
Overview of Field Losses 34
Nutrient Losses During Storage 34
Hay Storage Losses 34
Silage Storage Losses 37
Anaerobic losses 37
Aerobic storage losses 39
Overview of storage losses 42
Effect of Conservation Method on
Voluntary Feed Consumption 43
Effect of Conservation Method on
the Digestibility of Forages 53
Effect of Conservation Method
on Nutrient Utilization 56
Effect of Conservation Method
on Animal Performance 58
v
Page
III EFFECT OF HARVESTING SYSTEMS ON STORAGE LOSSES
AND NUTRIENT UTILIZATION OF BERMUDAGRASS
BY GROWING CATTLE AND SHEEP 61
Introduction 61
Materials and Methods 65
Forage Management and Storage 65
Storage Losses 66
Animal Trials 66
Intake 66
Performance 68
Digestibility and Nitrogen Balance 69
Analytical Procedures 70
Results and Discussion 73
Storage Losses 73
Composition of Forages 75
Fermentation Characteristics of Silages 79
Intake and Liveweight Change of Growing
Cattle 79
Digestibility 88
Nitrogen Utilization 90
General Discussion 93
IV EFFECT OF FEEDING ROUND BALE BERMUDAGRASS SILAGES
AND HAY ON THE PERFORMANCE OF COWS
AND THEIR CALVES 97
Introduction 97
Materials and Methods 98
Forage Management and Storage 98
Animal Management 99
Chemical Analyses 100
Statistical Analyses 101
Results and Discussion 102
Chemical Composition of Forages 102
Intake of Forages 102
Performance of Cows and Calves ! ! 105
General Discussion 109
V EVALUATION OF ROUND BALE BERMUDAGRASS FORAGES
AS WINTER FEED FOR GROWING CATTLE AND COWS 112
Introduction 112
vi
Materials and Methods 113
Nutrient Requirements of Animals 114
Nutrient Concentrations of Feeds 116
The Structure of the Model 116
Results and Discussion 120
Nutrient Specifications and Nutrient Contents
of Rations 120
Costs of Balanced Rations 123
General Discussion 129
VI CONCLUSIONS AND IMPLICATIONS FOR FUTURE RESEARCH ... 133
APPENDIX 135
LITERATURE CITED 195
BIOGRAPHICAL SKETCH 218
LIST OF TABLES
Page
TABLE
3.1 Effect of Wilting on Dry Matter and Gross Energy
Recovery at Feeding. Growing Cattle Experiments 74
3.2 Effect of Wilting on Characteristics of Forages.
Growing Cattle Experiment 1 76
3.3 Effect of Wilting on Characteristics of Forages.
Growing Cattle Experiment 2 77
3.4 Effect of Wilting on Dry Matter Concentration
and Fermentation Characteristics of Silages.
Growing Cattle Experiments 80
3.5 Effect of Wilting on Forage Intake.
Growing Cattle Experiment 1 . . . 82
3.6 Effect of Wilting on Liveweight Change.
Growing Cattle Experiments 83
3.7 Effect of Wilting on the Digestibility of
Nutrients. Sheep Experiments 89
3.8 Effect of Wilting on Nitrogen Utilization.
Sheep Experiment 2 91
4.1 Forage Characteristics . Cow Experiments 103
4.2 Intake of Bermudagrass Round Bale Silages and
Hay. Cow Experiments 104
4.3 Cow and Calf Performances on Bermudagrass Round Bale
Silages and Hay. Cow Experiment 1 106
4.4 Cow and Calf Performances on Bermudagrass Round Bale
Silages and Hay. Cow Experiment 2 107
5.1 Animal Requirements 115
viii
Page
5.2 Recovery of Round Bale Bermudagrass Forages
from Cutting to Consumption 117
5.3 Costs of Production of Round Bale Bermudagrass
Forages 118
5.4 Nutrient Concentrations and Cost of Forages
and Concentrates 119
5.5 Nutrient Specifications and Nutrient Contents
of Diets. Growing Cattle Experiments 121
5.6 Nutrient Specifications and Nutrient Contents
of Diets. Cow Experiments 122
5.7 Least Cost Diets at Ad Libitum Feeding of
Supplements. Growing Cattle Experiments 124
5.8 Least Cost Diets at 100% of Cow Requirements.
Cow Experiments 125
5.9 Least Cost Diets at 85% of Cow Requirements.
Cow Experiments 126
A.l Nutrient Recovery. Heifer Experiment 1 140
A.2 Analysis of Variance of Dry Matter and Gross Energy
Recovery at Feeding. Growing Cattle Experiment 1 141
A.3 Nutrient Recovery. Growing Cattle Experiment 2 142
A.4 Analysis of Variance of Dry Matter and Gross Energy
Recovery at Feeding. Growing Cattle Experiment 2 143
A.5 Forage Characteristics at Harvest.
Growing Cattle Experiment 1 144
A.6 Analysis of Variance of Forage Characteristics
at Harvest. Growing Cattle Experiment 1 145
ix
Page
A.7 Forage Characteristics at Feeding.
Growing Cattle Experiment 1 146
A.8 Analysis of Variance of Forage Characteristics
at Feeding. Growing Cattle Experiment 1 147
A.9 Forage Characteristics at Harvest.
Growing Cattle Experiment 2 148
A.10 Analysis of Variance of Forage Characteristics
at Harvest. Growing Cattle Experiment 2 149
A.11 Forage Characteristics at Feeding.
Growing Cattle Experiment 2 150
A.12 Analysis of Variance of Forage Characteristics
at Feeding. Growing Cattle Experiment 2 151
A.13 Silage Fermentation Characteristics.
Growing Cattle Experiment 1 152
A.14 Analysis of Variance of Silage Fermentation
Characteristics. Growing Cattle Experiment 1 154
A.15 Silage Fermentation Characteristics.
Growing Cattle Experiment 2 155
A.16 Analysis of Variance of Silage Fermentation
Characteristics. Growing Cattle Experiment 2 157
A.17 Forage Intake. Growing Cattle Experiment 1 158
A.18 Analysis of Variance of Forage Intake.
Growing Cattle Experiment 1 159
A.19 Forage Intake. Growing Cattle Experiment 2 160
A.20 Analysis of Variance of Forage Intake.
Growing Cattle Experiment 2 161
A.21 Bodyweight and Average Daily Gain.
Growing Cattle Experiment 1 162
A.22 Analysis of Variance of Bodyweight and Average
Daily Gain. Growing Cattle Experiment 1 163
A.23 Bodyweight and Average Daily Gain.
Growing Cattle Experiment 2 164
A.24 Analysis of Variance of Bodyweight and Average Daily
x