Top 50 words repeated twice, next 100 once, plus phrases. This seventh revised edition, Nutrient Requirements of Dairy Cattle 2001, applies new information and technology to current issues in the field of dairy cattle production. Reflecting the rapidly changing face of dairy cattle produc- tion and dairy science, it includes more comprehensive descriptions of management and environmental factors that affect nutrient requirements and provides expanded discussions of nutrient needs for various life stages and levels of production. A revised approach to predicting nutrient requirements increases the user's responsibility for accurately defining animals, diet, and management con- ditions to estimate nutrient requirements. A substantial part of the increase in decision-making power comes from the presentation of requirements with a computer model.
Computer models are the only effective means of taking animal variation into account.
Unlike static tabular values, computer models such as the one provided in this edition can describe animals in different states with differing needs. Chapter 1 presents a discussion of dry matter intake, including factors that affect intake and methods of predict- ing it. Characteristics of the animal's diet, environment, and physiologic makeup are considered, as are relevant management issues. After a brief description of available equations for predicting dry matter intake, the chapter discusses the dry matter intake equations included in this edition and closes with tables and graphs of intake across a lactation. Chapter 2 addresses energy, defining energy units and expressing methods of obtaining, estimating, and express- ing energy values of feeds.