Feed evaluation for animal production.

Animal production is concerned with providing food (and clothing) of animal origin for man. Animal production science, which underpins this goal, provides the rational basis for livestock management practices. Feed evaluation concerns the use of methods to describe animal feedstuffs with respect to their ability to sustain different types and levels of animal performance. In feed evaluation, emphasis is placed on determining specific chemical entities, although the physical characteristics of the feed are also important. Subsequently, the acquired data are used, with appropriate animal indices, in feeding systems comprising suitable predictive routines (normally based on empirical equations) to determine whether a desired level of animal performance can be achieved from various diets. The practical goal of feed evaluation is to optimize the efficiency of feed utilization, animal output and, ultimately, financial return to the producer. In this context, it is important to establish the potential of major feedstuffs and the need for appropriate supplements in order to overcome nutritional deficiencies and raise the level of performance. With respect to the animal, the level of performance will be dictated by the amount of feed voluntarily consumed and the efficiency of utilization of the major nutrients, namely energy and protein. Furthermore, the composition of the animal products (e.g. fat and protein in