Supplemental feeding of captive neonatal koalas (Phascolarctos cinereus).

Koalas (Phascolarctos cinereus) are cautious animals, making supplemental feeding of neonates challenging because of disturbances to the normal routine. However, supplemental feeding is beneficial in improving juvenile nutrition using less formula than required for hand-rearing, and allowing maternal bonding to continue through suckling. In this study, two neonatal koalas, delivered by the same mother in 2 years, exhibited insufficient growth post-emergence from the pouch; supplemental feeding was therefore initiated. The amount of formula fed was determined according to the product instructions, and offspring weight was monitored. Slower than normal growth was not initially noticed in the first offspring. This caused delayed commencement of supplemental feeding. An attempt was made to counteract this by providing more formula for a longer period; however, this meant No. 1 was unable to eat enough eucalyptus when weaning. Supplemental feeding was started earlier for the second offspring than for the first, and was terminated at weaning; this juvenile showed a healthy body weight increase. Furthermore, it was able to eat eucalyptus leaves at an earlier stage than No. 1. Although No. 1 showed delayed growth, both koalas matured and are still living. This study showed that supplemental feeding is useful for koalas, if the mother will accept human intervention. The key factors for successful supplemental feeding of koalas identified by comparing the two feeding systems observed in this study are that: (1) it should be initiated as soon as insufficient growth is identified; and (2) it should be terminated before weaning age. Zoo Biol. 36:62-65, 2017. © 2016 Wiley Periodicals, Inc.