Macaque the other monkey's mouth. Several species of macaque are used extensively in animal testing, particularly in the neuroscience of visual perception and the visual system. Nearly all (73–100%) pet and captive rhesus macaques are carriers of the herpes B virus. This virus is harmless to macaques, but infections of humans, while rare, are potentially fatal, a risk that makes macaques unsuitable as pets. Urban performing macaques also carried simian foamy virus, suggesting they could be involved in the species-to-species jump of similar retroviruses to humans. In Vietnam, macaque is eaten by some people as bushmeat. In January 2018, scientists in
Celebes crested macaque Paignton Zoo are among a number of mostly European zoos which hold "ex-situ" breeding populations of this animal. Since 2006, the "Macaca Nigra Project" has been studying the biology and promoting the conservation of this species. The project, a collaboration between the German Primate Center and the Bogor Agricultural Institute, is run by Antje Engelhardt and located in the Tangkoko reserve, home of the biggest crested macaque population remaining in the species' original distribution range. Nevertheless, despite being critically endangered, crested black macaque are still being hunted down and slaughtered. Crested black macaque is considered a delicacy by local residents.