The subject may be unpalatable, but animal research has improved the quality of human life.
Researchers have defended animal testing, pointing out that it would be unethical not to do it.
Treatments for diseases such as diabetes and polio were made possible through animal research.
Animals are currently being used in hepatitis-, HIV- and stem cell-related research, among others.
US researchers defended animal testing, telling a small group at one of the biggest science conferences in the United States that not doing animal research would be unethical and cost human lives.
The researchers, who are or have been involved in animal research, told a symposium at the annual meeting of the American Association for the Advancement of Science (AAAS) that testing on animals has led to "dramatic developments in research that have improved and affected the quality of human life."
"To not do animal testing would mean that we would not be able to bring treatments and interventions and cures in a timely way. And what that means is people would die," Stuart Zola of Emory University, which is home to the Yerkes National Primate Research Center, told AFP after the symposium.