Changes in milk composition during lactation in the eastern barred bandicoot (Perameles gunnii) (Marsupialia:Peramelidae)

Abstract

Perameles gunnii is a small to medium-sized omnivorous marsupial. We measured milk components from Week 4 until weaning at Week 8; these showed marked quantitative and qualitative changes. The milk produced in the early stages of lactation was dilute, ~28% solid (w/w). At four weeks carbohydrate, protein and lipids were also at low levels: 2.0 g (100 mL)–1, 4.5 g (100 mL)–1 and 3.1 g (100 mL)–1 respectively. At the mid-phase of lactation solids reached 36%, carbohydrate 5.5 g (100 mL)–1, protein 10.0 g (100 mL)–1 and lipids 8.5 g (100 mL)–1. The energy content of the milk at 4 weeks of lactation was 2.25 kJ mL–1 while at pouch vacancy it reached 8.86 kJ mL–1. At 8 weeks the pouch young was almost weaned and all the constituents but carbohydrates had increased significantly. We compared the milk components of the eastern barred bandicoot with those of other marsupial species and with the Wombaroo milk formula used by zookeepers and carers to hand-raise orphaned bandicoots. We found the milk formula to be deficient in both protein and lipid.