Skeletal muscle-based thermogenesis and behavioural thermoregulation in wild boar

One of the female wild boards (with ear tag) at the Research Institute of Wildlife Ecology (Photo Julia Nowack)
Photo of a wild boar female with ear tag 1

The project “Skeletal muscle-based thermogenesis and behavioural thermoregulation in wild boar” evaluates the importance of a recently discovered mechanism of heat production via skeletal muscle. Small mammals and neonates typically stay warm in winter by producing heat via nonshivering thermogenesis in the brown adipose tissue, while larger mammals were long believed to rely primarily on shivering and behavioural adaptations.

A recent discovery of a second mechanism of heat production in skeletal muscle, which does not require muscle contractions, has changed this view. While the evolution of brown adipose tissue presumably allowed small mammals to inhabit colder climatic zones, muscle-based nonshivering thermogenesis could be the dominant mechanism of heat production in mammals that lack brown adipose tissue, or in which the activity of brown adipose tissue is down regulated after the neonatal period. The planned project at the University of Veterinary Medicine Vienna uses wild boars (Sus scrofa), a species that lost functional brown adipose tissue, to gain insights into the significance and quantitative contribution of this skeletal-based heat production for mammalian thermoregulation.  Wild boars likely undergo seasonal cycles in the capacity of muscle-based thermogenesis, with a higher capacity of heat production during experimentally lowered ambient temperature, whereas at the same time the intensity of shivering is reduced.

Furthermore, the project aims to evaluate the involvement of essential dietary fatty acids on muscle thermogenesis and aims to determine the significance of behavioural thermoregulation. Behavioural thermoregulation will likely play a major role especially for piglets, since it is proposed that the capacity for muscle-based thermogenesis evolves during the first days after birth.


Duration 01/2017-12/2020

In juvenile domestic pigs cold-induced shivering intensity decreases whereas mass specific metabolic rate (i.e. heat production) increases over the first days of life (data from Table 2 in Berthon et al. (1994)). This change in the ratio between shivering and metabolic rate leads to a >5-fold apparent improvement of shivering efficiency. We hypothesize that the enhancement of thermogenesis is due to an increasing contribution of SERCA-based futile Ca2+ cycling in skeletal muscles.
Graph on domestic pig metabolism 2


The project is supported by a Feodor Lynen Scholarship of the Alexander von Humbold Foundation.


Scientific contact at FIWI

A.o.Univ.Prof. Dr. Thomas Ruf, Leiter der AG Ökophysiologie & Populationsökologie, Forschungsinstitut für Wildtierkunde und Ökologie, Vetmeduni Vienna

T. +43 (1) 25077-7150

Email Thomas Ruf


Dr. Julia Nowack, Ökophysiologie & Populationsökologie, Forschungsinstitut für Wildtierkunde und Ökologie, Vetmeduni Vienna

T: +43 (1) 25077-7152

Email Julia Nowack


General contact


Savoyenstraße 1
A-1160 Wien

T +43 1 25077-7900
F +43 1 25077-7941

Email FIWI