Monograph. - National academy press, Washington D.C., 1996. - 248 p. — ISBN: 0-309-59241-0.
Subcommittee on Beef Cattle Nutrition, Committee on Animal Nutrition, National Research Council
This seventh revised edition of Nutrient Requirements of Beef Cattle is a significant revision of the sixth edition. One major improvement involves expansion in describing different cattle. Requirements are also defined in terms of a greater variety of management and environmental conditions than was possible in previous editions. One result of this innovation is that there is now a greater responsibility for the user to define the animals and their conditions before proceeding to determine nutrient requirements. A second major improvement involves presentation of requirements using computer models. Computer models are the only effective way to take animal variation into account. Also important is the fact that computer models can describe the dynamic state of the animal, which is not possible with the presentation of discrete tabular values of nutrient requirements alone.
OVERVIEWENERGY
Energy Units
Requirements for Energy
PROTEIN
Microbial Protein Synthesis
MP Requirements
Conversion of MP to NP
GROWTH AND BODY RESERVES
Energy and Protein Requirements for Growing Cattle
Energy and Protein Requirements for Breeding Herd Replacements
Energy and Protein Reserves of Beef Cows
REPRODUCTION
Gestation
Lactation
Breeding Performance
MINERALS
Macrominerals
Microminerals
VITAMINS AND WATER
Fat-Soluble Vitamins
Water-Soluble Vitamins
Water
FEED INTAKE
Factors Affecting Feed Intake
Prediction of Feed Intake by Beef Cattle
Special Considerations for All-Forage Diets
IMPLICATIONS OF STRESS
Energy
Protein
Minerals
Vitamins
TABLES OF NUTRIENT REQUIREMENTS
Example Tables for Growing and Finishing Cattle
Example Tables for Breeding Bulls
Example Tables for Pregnant Replacement Heifers
Example Tables for Beef Cows
Table of Energy Reserves for Beef Cows
Table of Maintenance Requirement Multipliers for Environmental Conditions
PREDICTION EQUATIONS AND COMPUTER MODEL
Requirements for Both Levels
Predicting Dry Matter Intake
Supply of Nutrients
Feed Composition Values for Use of the NRC Model
COMPOSITION OF SELECTED FEEDS
Effects of Processing Treatments
APPENDIX: NRC MODEL USER’S GUIDE