Adoption success under single-cage conditions by cynomolgus macaque mothers (Macaca fascicularis)

Retrospective data were studied to determine the success of experimental adoption by 122 cynomolgus macaques kept in individual cages at the Tsukuba Primate Center. The four types of adoption procedures included (1) singletons adopted after weaning (SAW)-21 cases; (2) singletons adopted after stillbirth (SAS)-20 cases; (3) singletons adopted after forced separation of the biological infant during the nursing period (SAF)-4 cases; and (4) adoption of a second "twin" while still nursing a biological infant (TA)-77 cases. Adoption was defined as successful if the mother nursed the foster infants for at least 7 days. Success rates (percent) were 47.6 for SAW, 75 for SAS, 100 for SAF, and 74 for TA. Success was affected by the postbirth stage of foster mothers at adoption but not by foster infant age or sex.