Veterinary paediatrics is concerned with the health, growth and development of young animals. In this chap­ter the following definitions will be used:

• Neonate - from birth to several weeks of age

• Juvenile - passed the neonatal phase but not yet weaned

• Sub-adult - weaned but not yet sexually mature

• Paediatric or young - neonates, juveniles and sub­adults combined

• PY (pouch young) - marsupial young that are at a pre- emergent phase of development (includes all neonates and some juveniles).

Paediatric patients comprise a high proportion of the Australian mammal cases presented to veterinarians for evaluation and care. Many of the free-ranging cases are orphans that are sick or injured at initial presentation. The spectrum of health problems encountered differs from that of adults. Moreover, an animal’s response to illness and stress varies with age and the stage of develop­ment and this needs to be considered during the assess­ment and treatment of paediatric patients. This chapter provides clinically useful information for the paediatric consultation to augment that presented in McCracken (2008). Although general principles will apply across a range of species, given the relative immaturity of marsu­pials at birth, and the common practice of hand-rearing marsupial orphans, this chapter will focus on this taxo­nomic group.

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