Most prosimians are not aggressive toward humans, but caregivers might find it startling when an aye-aye jumps toward them or even clings to them. They are quite fearless and extremely inquisitive and will examine hands, head, feet, etc., in detail.
Nonaggressive prosimians, however, will strenuously resist restraint. Sifakas can deliver powerful kicks, the aye-aye has a powerful bite, lorisids are adept biters, and the slow loris even has a poisonous mix of saliva and glandular secretions.
During capture or restraint, many prosimians will resist vigorously with some peril to both handler and animals. Violent leaping and struggling in nets can produce self-injuries in indrids, and tarsiers seem especially stressed by handling. A minimum of restraint should be used, and personnel should be mindful of the fragility of the smaller species. Capturing animals while they are asleep in nest tubes or boxes is preferable to vigorous chasing.
Whereas most prosimians exhibit few health problems, some special comments are in order. Infants that are rejected by their mothers and hand-reared are notoriously sickly. Whenever possible, rejected infants should be fostered on another mother; lemurid mothers can easily rear two young at once. As a health precaution, lemurids should be weighed at least twice a year and whenever they are handled or there is concern for their health. Minimal interference in groups in large enclosures is possible. Lemurids readily recover from moderate trauma, and even simple fractures have been noted to have healed without treatment (although we do not advocate ignoring such injuries). When injuries (e.g., lacerations, fractures) require treatment, every effort should be made to provide treatment that will allow the animal to be returned immediately to its group. That will minimize the possibility of group rejection, which might occur after a separation of only 1 or 2 days. Substantial effort should be made not to separate sick or injured lemurs from their social group, lest separation cause depression or social rejection.
Weight checks will reveal normal seasonal weight changes associated with winter torpor, but the weight of mouse and dwarf lemurs should otherwise be stable among adults. Fecal examinations (flotation and smear) should be carried out twice a year or whenever stool is abnormal. Newly arrived animals should receive fecal examinations weekly for at least 3 weeks. Stress produced by overcrowding sometimes leads to illness, especially liver and kidney problems.
Sifakas are very susceptible to changes in diet, which can lead to diarrhea. Trichomoniasis can be a secondary problem with such diarrhea and requires treatment with metronidazole. Diarrhea and other septic conditions in indrids