Fostering an infant rhesus monkey on to a non-lactating female in a group-housed breeding colony.

The reported case describes how an orphaned infant rhesus macaque (Macaca mulatta) was adopted by a non-lactating female animal from the same breeding group. Experience at our institution over the last 27 years has indicated that fostering infant rhesus macaques on to other females is unsuccessful. However, the described infant was held and carried by another female in his breeding group when his mother was sick. After the death of his natural mother, fostering on to a lactating female was attempted but failed, and he was returned to his breeding group and was adopted by the non-lactating female. The infant was hand-fed by animal care staff, and the feeding regimen is described. The fostering was successful, and the infant has had access to a mother figure and peers, although extensive contact with humans initially was necessary for feeding. This contact did not, however, appear to be detrimental to the mother-infant and peer-infant bond, as the infant did not preferentially seek human contact over monkey contact, and he was at no point rejected by mother or group. The disruption caused by removal and replacement of the infant did not cause agitation or increased fighting within the group. We anticipate that the contact with a matriarchal figure in a primate breeding group will minimize the psychological disturbances frequently found with hand-reared macaques.