Pye Geoffrey W, Gait Sarah Catherine, Mulot Baptiste, de Asua Maria Delclaux Real, Martinez-Nevado Eva, Bonar Christopher J, Baines Stephen J, Baines Elizabeth A
San Diego Zoo Global, 2920 Zoo Drive, San Diego, California 92101, USA.
J Zoo Wildl Med. 2013 Jun;44(2):273-9. doi: 10.1638/2012-0031R1.1.
Due to climate restrictions in parts of North America and Europe, koalas (Phascolarctos cinereus) are housed indoors. Koala young (joeys) raised indoors are susceptible to the development of metabolic bone disease (MBD) due to a lack of exposure to natural ultraviolet light to themselves and their female parents (dams). In this retrospective study, radiographs from 27 koala joeys born at four zoos in North America and two zoos in Europe were evaluated for signs of MBD. Eight of the joeys were radiographically diagnosed with MBD and four additional joeys were considered suspect MBD cases; in two joeys absence or presence of MBD could not be determined. All joeys had mild to severe hip and shoulder dysplasia. There were significant associations between a lack of exposure to UV light and MBD development and between MBD and the degree of severity of hip and shoulder dysplasia. It is recommended to house breeding female koalas and their joeys outdoors whenever possible.
