Sustainability of animal production systems: an ecological perspective.

The question of sustainability of agricultural production and the use of natural resources has become a popular topic. Most scientists agree that current systems are generally non-sustainable. Current rates of resource extraction will lead us to a depleted earth in the future. Sustainability is defined in many ways. For this paper sustainability should be considered the overlap of what is wanted and what is ecologically possible. Attempts have been made to place a quantitative measure on sustainability. However, it should be considered a trajectory or goal, a direction that guides constructive change, rather than a single quantitative measure. Research and extension personnel may have to take a broader look at their efforts and expand their knowledge base in order to address the issue of sustainable production systems. Both natural events and those caused by humans bring about changes in production potential that require shifts in management. Uncertainty and change should be incorporated into adaptive management strategies. Interdisciplinary efforts are needed to confront these issues. Animal scientists need to formulate management systems that are environmentally compatible or face restrictive legislation that will force change. Members of the American Society of Animal Science seem to agree: efficient and sustainable use of natural resources appears in the draft of the Strategic Plan of the Society, and a poll of members revealed that environmental concerns about animal agriculture was a primary issue facing animal scientists.