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Chimpanzees in Japan Need Help


Primate Research Institute, Kyoto University

For over a decade now, there have been no invasive studies of chimpanzees in Japan. However, it has come to our attention that a medical company has recently set out to subject the chimpanzees in its care to invasive studies of the hepatitis C virus as well as certain types of gene therapy. The number of biomedical subjects in invasive studies will increase in the nearest future unless we attempt and succeed in finding an acceptable solution. As a first step, I asked Japanese scientists to organize SAGA (Support for African/ Asian Great Apes) symposium in November 1998 that have decided to put forward an agenda calling for the cessation of invasive studies in captive chimpanzees.

Japan is at present home to 388 chimpanzees, 37 gorillas, and 57 orangutans. There are currently no bonobos in the country. All gorillas and orangutans are housed in zoos. Of the 388 chimpanzees, a group of 11 is kept at the Primate Research Institute of Kyoto University, participating in noninvasive studies such as cognitive and behavioral research. A further 237 chimpanzees are distributed over 50 zoos, and 4 belong to circuses or commercial productions. The remaining 136 chimpanzees, one third of the total population in Japan, are kept in the facilities of three medical companies. They have 107, 16, and 13 chimpanzees, respectively. All of these are either chimpanzees who had been used in hepatitis B research, or the descendants of the latter.

A total of 151 chimpanzees served as hepatitis B research subjects during the period between 1975 and 1986 in Japan. Of this group, 83 chimpanzees had been imported directly from Sierra Leone, until Japan ratified CITES in 1980. Biomedical researchers were supported financially by the Ministry of Health and Welfare, and played the key part in conducting invasive research. A number of chimpanzees were kept in the scientists' associated universities, while some others were housed in the three medical companies. Hepatitis B research using chimpanzees ended in Japan in 1987, thanks to the development of a vaccine for the hepatitis B virus. By that time, 45 chimpanzees participating in the relevant studies had already died. Researchers retired and sent the surviving chimpanzees on to the medical companies. The chimpanzees received in this way were subsequently bred in a medical company and their numbers increased.

A few researchers continue to nurture an interest in hepatitis C research using chimpanzees. They recently launched an experiment of the infectious hepatitis C virus in healthy chimpanzees in collaboration with the medical company. Other researchers plan to begin gene therapy studies for diseases such as cancer and AIDS in chimpanzees. The experiments would entail safety checks of the vectors that carry specific genes into target organs. The company, which has been encouraged by the biomedical use of chimpanzees in the USA, appears in its policies to strongly favour the biomedical/ invasive use of its 107 chimpanzees. Ministry of Education, Science, and Culture has never financially supported such a kind of invasive study in chimpanzees in Japan, but the Ministry of Health and Welfare has.

The researchers of chimpanzees are aware of how small the distances are that separate chimpanzees and other great apes from humans. All the great ape species are listed as "endangered" in CITES. Their numbers in the wild are decreasing, and captive populations remain small. Individuals survive 40 to 50 years, in some cases even longer. These characteristics are not congruent with the standards for so-called experimental animals. We believe that there need to be serious constraints on the biomedical use of chimpanzees and other great apes. SAGA symposium 1998 proposed the following agenda to promote our scientific understanding of all great apes. The agenda is approved by the following primatologists who participated the SAGA symposium: Toshisada Nishida, Yukimaru Sugiyama, Tasuku Kimura, Osamu Takenaka, Shozo Kojima, Takayoshi Kano, Juichi Yamagiwa, Jun'ichiro Itani, Masao Kawai, Jane Goodall, and Jan van Hooff.

  • First, we shall undertake action for the conservation of the great apes and their natural habitat.

  • Second, we shall endeavor to enhance the quality of life of the great apes in captivity.

  • Third, we shall not use the great apes as subjects in invasive studies, but promote our scientific understanding through non-invasive techniques.

For our purposes, the word "invasive" refers to the treatment that causes irreversible deficits of normal function. In short, illegal or non- ethical treatment prohibited in the case of human subjects is to be likewise prohibited in the great apes.

Based on this SAGA agenda, we hope to halt current trends of invasive biomedical use of chimpanzees in Japan. We will then devise further plans for the scientific use of the 136 chimpanzees currently in the care of the medical companies from a broader perspective. Researchers, medical companies, Ministries, and the people who are working for the great apes need to cooperate together to develop a suitable solution, as these chimpanzees represent unique genetic resources existing in Japan. The founding of a national institute for the scientific and noninvasive use of captive chimpanzees should be seen as a realistic goal.

I hope that primatologists all over the world will demonstrate their approval and support of SAGA attempt toward a better life for chimpanzees and other great apes in the coming century. Further correspondence should be the following e-mail address:

This article appeared in "PAN Africa News", Vol.5, No.2, November 1998.


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