Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
INTRODUCTION Water, energy, protein, vitamins, and minerals must be provided in the correct amounts and proportions if op- timum results are to be obtained in the support of mainte- nance, normal growth, and reproduction in swine. Although the exact quantitative need for each nutrient is not known, the most reliable estimates of requirements have been compiled and are presented in Tables 5-8. Requirements, as presented, should be considered as minimum requirements and do not include a margin of safety. The recommendations are based upon the assump- tion that diets will contain about 90 percent dry matter. Where values from several comparable experiments were available for consideration, the approximate average of those values was used. References to corn-soybean meal or grain-soybean meal diets refer to vitamin and mineral fortified diets of this general composition. It can be as- sumed that recommendations will also apply following the inclusion of most other energy- and protein-furnishing ingredients. It is known that breed, strain, and sex affect growth rate, feed conversion, and carcass composition, and, therefore, these factors influence nutrient requirements. The re- quired dietary level will also be influenced by: 1. Feed intake 2. Energy density of the diet 3. Level and interaction of nutrients in the diet 4. Availability of nutrients to the animal 5. Presence and level of feed additives 6. Environmental temperature, housing conditions, and level of subclinical disease 7. Presence of toxins, inhibitors, or molds in the diet 8. Expected level of performance and carcass composi- tion.