Lee Katterman | Mar 1, 1992 | 5 min read
The U.S. Department of Agriculture estimates that each year as many as 20 million animals are used in various university and industry settings for basic research and product testing. This figure represents a sizable drop from the late 1970s, when the USDA estimated that about 33 million animals per year were used. Two reasons are usually cited for this trend, says Daniel Ringler, director of the Unit for Laboratory Animal Medicine at the University of Michigan. First, many researchers have al