Oestrus in the Julia Creek dunnart (Sminthopsis douglasi) is associated with wheel running behaviour but not necessarily changes in body weight, food consumption or pouch morphology

Abstract The Julia Creek dunnart ( Sminthopsis douglasi ) is an endangered carnivorous marsupial belonging to the family Dasyuridae. This study investigated the oestrous cycle of this species in terms of its reproductive physiology and behaviour to explore more efficient methods of oestrus detection. Ten sexually mature captive female dunnarts were monitored daily at David Fleay Wildlife Park, Burleigh Heads, Australia, from mid September to late December 2006 for changes in urogenital cytology within the urine (0, 1+, 2+ and 3+), running wheel activity, body weight, uneaten food, faecal steroid metabolites (progesterone and oestradiol) and pouch development. Periods of increased running wheel activity were associated ( p  = 0.004) with an increase in the proportion of cornified urogenital epithelial cells found in the urine; periods of decreasing weight ( p p n  = 20) or peak distance travelled (mean ± SD: 25.4 ± 5.7 days; n  = 20). Changes in the concentration of oestradiol metabolites in Julia Creek Dunnart faeces were not useful in characterising the oestrous cycle. Wheel running activity declined markedly with increased faecal progestagen concentration. The majority of the pouch variables examined showed maximum development during the inter-oestrus period but as there was considerable variation between animals, the pouch was not considered a useful index of oestrus.