Future Costs of Chimpanzees in U.S. Research Institutions.

Abstract

The International Species Inventory System (ISIS) keeps a registry of most of the captive chimpanzees kept in zoos and research colonies throughout the world (Seal and others 1977). The ISIS database recorded a total of 2,572 chimpanzees maintained in captivity worldwide as of January 1995. More than half of these animals (1,455 in all) are housed at 6 biomedical research institutions in the United States. Support for these animals comes principally from commercial sources (mostly the pharmaceutical industry), and National Institutes of Health (NIH) research and animal resource grants and contracts. Chimpanzees have been used extensively in hepatitis vaccine development (Purcell 1992), and are currently the only animal model known to be susceptible to HIV-1 infection (Warren and Dolatshahi 1994). In 1973 the United States signed the Convention on International Trade in Endangered Species (CITES), and in 1977 the U.S. Fish and Wildlife Service designated wild chimpanzees as endangered and chimpanzees in captivity as threatened. Since further importation from the wild is prohibited, biomedical research needs for these animals must be met from domestic sources. Because there was concern that fertility, particularly of colony-born animals, might not be high enough to produce enough chimpanzees for U.S. biomedical needs, NIH initiated a chimpanzee breeding and research program in 1986 to help fund production of animals in 5 of the 6 research colonies (Wolfle and April 1994). As the result of developments in husbandry funded in part by these grants, breeding programs in all 6 colonies have been successful, and it appears that the U.S. chimpanzee population as a whole has the capability to be self-sustaining. The biomedical value of chimpanzees lies in their close evolutionary relationship and concomitant physiological and immunologic similarities to humans. These characteristics are balanced against difficulties in caring for such a large, late-maturing,