This volume emanates from The 7th Biennial Conference of the Society for Tropical Veterinary Medicine held during June 2003 at Iguazzu Falls, Brazil. The overall theme of the conference was the impact of ecological changes on tropical animal health and disease control. Areas addressed included ecosystem health and its impact on tropical animal health, factors influencing the host boundaries of disease agents, trends in tropical animal health, foot-and-mouth disease and its impact within the tropics, genomics and the use of vaccines to manage or eliminate disease threats, and impacts on animal agriculture and other related topics in tropical veterinary medicine.