We studied the interaction between torpor and reproduction in free-ranging female Tasmanian echidnas using a combination of techniques including urogenital smears, hormone analysis, ultrasonography, external temperature loggers and camera traps. Male echidnas initiated mating activity by locating hibernating females. All females that mated or were disturbed by males prior to July 27 re-entered hibernation, including many that were pregnant. Pregnant females only entered hibernation in early pregnancy when plasma progesterone concentrations were about twice basal and progesterone then remained constant during torpor. By re-entering hibernation pregnant females extended their gestation period and delayed egg-laying. Progesterone peaked 4–6 days before egg-laying, then dropped rapidly.

Item Type:	Refereed Article
Keywords:	monotreme, progesterone, reproduction, torpor, vaginal cytology, short-beaked echidna
Research Division:	Biological Sciences
Research Group:	Zoology
Research Field:	Comparative physiology
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the environmental sciences
UTAS Author:	Morrow, GE (Ms Gemma Morrow)
UTAS Author:	Jones, SM (Professor Susan Jones)
UTAS Author:	Nicol, SC (Associate Professor Stewart Nicol)
ID Code:	115974
Year Published:	2017
Web of Science® Times Cited:	8
Deposited By:	Zoology
Deposited On:	2017-04-24
Last Modified:	2018-07-30
Downloads:	0