ABSTRACT
Animals make many contributions to tropical societies. One of the most important of these is food, especially meat, eggs and dairy products. Animal protein makes up a much smaller proportion of total dietary protein in most tropical countries than in temperate countries (Figure 10.1). In contrast to the situation in most temperate regions, where dietary protein levels are generally more than adequate, protein-energy malnutrition is a major health problem in the tropics, especially among children (Golden 1993). Animal products are generally ranked more highly than plant foods as a protein source owing to their high content of essential amino acids (Table 8.2), and are a good source of many other nutrients (Southgate 1993). Although meat is not an essential dietary component, supplementation of plant-based diets with small amounts of suitable animal products can make a nutritionally complete diet easier to achieve (Garlick and Reeds 1993). The efficiency with which animals turn plant matter into protein varies among species (Lovell 1979), but in general they are relatively inefficient as protein-producing systems. Their production primarily for this purpose is likely to be desirable only in certain circumstances such as on a small scale to supplement protein quantity and/or quality in a plant-based diet, as a way of producing food from lands which are marginal or unsuitable for crop production such as those in arid and semi-arid regions, and as a method of making use of resources such as crop residues or unused land within cropping systems.
