Twin infant black and white ruffed lemurs, male and female, were fostered on a part-time basis, in conjunction with hand-rearing, with an adult pair who were highly related to them. The adult female showed allomaternal behaviour towards the twins, although she did not attempt to suckle
them. The adult male ignored the twins for the first few weeks but as they became more mobile and playful he frequently initiated play with one or both. Growth rates showed a significant trend when compared with parentally raised and hand-reared infants, with the fostered twins growing at
rates intermediate between those found under the two other rearing methods. Fostering of rejected infants as a captive management strategy is advocated as an alternative to traditional hand-rearing techniques because of the welfare advantages to both infants and foster parents.