Food from animals: environmental issues and implications

Abstract

The world's population of 5 000 000 000 is estimated to use annually some 600 000 000 000 kg of meat, milk and eggs from animals (Table 1.1). An increase in per capita income brings about an increase first in the consumption of crop products, but soon after, an increase also in more costly animal products; this is a positive relationship which is maintained until the highest income levels are attained, at which point the consumption rate for animal product plateaus (Figure 1.1). It is not surprising, therefore, that animal production output is predicted to stabilise in many countries of the developed world but to expand in developing countries. Relative national desires to increase and cheapen animal production on the one hand, and to control and proscribe on the other, are closely reflected in the attitudes of each society to environmental and ethical issues related to the consumption of meat, milk and eggs. Thus it is that consideration of the environmental aspects of the production of human food from animals tends to be a science which is both recent in origin and the privilege of the nutritionally satisfied. The average European consumes 80 kg of meat per capita annually. However, animal production, if allowed to become unbalanced, may also induce environmental problems in developing countries; extensive farming of herbivorous stock has led in some areas to overgrazing and land erosion. These occurrences are particularly distressing where the food product is destined for export out of the area of its primary production.