The number of animals used in research in the United States has fallen more than 50 percent since 1968, scientists at Tufts University said Wednesday in a report.
Reviewing how the animals are treated, the researchers said the amount of pain caused was understated by universities and company laboratories and overstated by animal rights advocates.
The report of the Tufts University Center for Animals and Public Policy was presented at a meeting in Washington.
Dr. Franklin Loew, director of the center, and Dr. Andrew Rowan, chief author of the report, said it was an attempt to view the issue from a middle ground between animal protection groups and scientists who use animals in research, and to help bring the two sides closer.
All sides seem to agree that the federal Agriculture Department should do a more complete job of keeping track of how many animals are used in research and whether they suffer as a result.
The report noted that the department kept statistics only on dogs, cats, primates, rabbits, hamsters and guinea pigs. The number of these animals used by scientists has dropped about 50 percent to 1.2-million in 1992 from a high of 2.3-million in the late 1960s.
Rats and mice make up more than 80 percent of animals used in laboratories, however, and the number used is less certain. Department of Defense numbers show that all animal use, including rats and mice, dropped to 267,000 in 1991 from 412,000 in 1983.
Pharmaceutical companies have said their animal use has dropped sharply.
The same drastic drop in animal use has been reported in Europe, where more accurate numbers are kept.