Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: May 15, 2009
Publication Date: January 29, 2010
Citation: Powell, J.M., Russelle, M.P., Martin, N.P. 2010. The United States: Trends in the Dairy Industry and Their Implications for Producers and the Environment. In: Gerber, P., et al. (Ed.) Livestock in a Changing Environment. Volume 2. Experiences and Regional Perspectives. London, England: Island Press. p. 115-139. Technical Abstract: Consumer demand, technical economies of scale, enhanced animal genetics and nutrition, and the widespread use of relatively inexpensive feeds, diet supplements and fertilizers continue to transform animal agriculture in the USA. The transition to fewer and larger livestock farms has encompassed a greater use of imported feed resulting in manure nutrients that can surpass the recycling capacity of associated pastures and croplands. The liberal use of fertilizers in combination with manure and other agricultural nutrient sources can have numerous adverse environmental impacts, including pollution of land and water through runoff and leaching, and gaseous emissions that can adversely affect human health, pollute natural ecosystems and contribute to global climate change. Federal and state regulations and local ordinances have been promulgated to mitigate nutrient loss and environmental pollution from livestock farms. The purpose of this chapter is to provide an overview of the trends and drivers of change in animal agriculture in the USA with a focus on the dairy industry; the consequences of excessive nitrogen (N) and phosphorus (P) use in dairy systems; and governmental policy and industry responses to public concerns about environmental pollution by animal agriculture. The chapter concludes with a discussion of the partnerships, financial incentives and policies required for implementing practices that maintain farm profits while reducing environmental impacts of animal agriculture.