The resources required to raise livestock and the impacts of farm animals on environments vary dramatically depending on the animal, the type of food it provides, the kind of feed it consumes and where it lives, according to a new study that offers the most detailed portrait to date of "livestock ecosystems" in different parts of the world.
The study, published today in the Proceedings of the National Academy of Sciences (PNAS), is the newest comprehensive assessment assembled of what cows, sheep, pigs, poultry and other farm animals are eating in different parts of the world; how efficiently they convert that feed into milk, eggs and meat; and the amount of greenhouse gases they produce.
The study, produced by scientists at the International Livestock Research Institute (ILRI), the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the International Institute for Applied Systems Analysis (IIASA), shows that animals in many parts of the developing world require far more food to produce a kilo of protein than animals in wealthy countries. It also shows that pork and poultry are being produced far more efficiently than milk and beef, and greenhouse gas emissions vary widely depending on the animal involved and the quality of its diet.
"There's been a lot of research focused on the challenges livestock present at the global level, but if the problems are global, the solutions are almost all local and very situation-specific," said Mario Herrero, lead author of the study who earlier this year left ILRI to take up the position of chief research scientist at CSIRO in Australia.
"Our goal is to provide the data needed so that the debate over the role of livestock in our diets and our environments and the search for solutions to the challenges they present can be informed by the vastly different ways people around the world raise animals," said Herrero.
"This very important research should provide a new foundation for addressing the sustainable development of livestock in a very resource-challenged and hungry world, where, in many areas, livestock can be crucial to food security," said Harvard University's William C. Clark, editorial board member of the Sustainability Science section at PNAS.
For the last four years, Herrero has been working with scientists at ILRI and the lIASA in Austria to deconstruct livestock impacts beyond what they view as broad and incomplete representations of the livestock sector. Their findings—supplemented with 50 illustrative maps and more than 100 pages of additional data—anchor a special edition of PNAS devoted to exploring livestock-related issues and global change. Scientists say the new data fill a critical gap in research on the interactions between livestock and natural resources region by region.
The initial work was funded by ILRI and the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).
Story source: Burness Communications news release via EurekAlert!, 16 Dec 2013
Journal Reference: M. Herrero, P. Havlik, H. Valin, A. Notenbaert, M. C. Rufino, P. K. Thornton, M. Blummel, F. Weiss, D. Grace, M. Obersteiner. Biomass use, production, feed efficiencies, and greenhouse gas emissions from global livestock systems. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1308149110