Navigation Links
Fat and fit
Date:10/22/2013

In the dog days of summer, female edible dormice (Glis glis) are busy caring for their young but immediately after this energy-intensive period they start to replenish their fat stores to cope with the upcoming winter. Unfortunately, this habit seems to give the animals a pleasant taste and dormice have long been viewed as a special delicacy. The Romans even kept them in captivity to fatten them up for eating, which explains the "edible" part of their name.

Later in the year, when outside temperatures drop and the leaves turn colour, dormice move to their hibernation quarters where they will spend many months without food. During hibernation, dormice enter phases of so-called torpor: they drastically reduce their metabolic rate and lower their body temperature to that of the surrounding environment. Every few weeks they boost their metabolism and their body temperature returns for a few hours to "normal" levels, although the animals do not really "wake up" or leave their underground hibernacula. These periods of arousal, which all hibernating mammals experience, are when most of the fat is burned during hibernation. It is widely assumed that the periodic warm-up phases serve to counteract the negative impacts of a reduced metabolic rate, such as drops in immune competence at lower body temperatures.

Individual dormice enter hibernation with different fat reserves but how dormice use their body fat reserves to optimize their chances of surviving in a good condition has remained a matter of conjecture. Together with Fritz Geiser of the University of New England, Claudia Bieber and colleagues at the Vetmeduni Vienna have analysed body temperature data collected continuously from 42 hibernating dormice. Surprisingly, the fatter animals did not shorten their hibernation, although environmental conditions would have allowed them to do so. Some animals even hibernated in summery conditions until the beginning of July. Instead of emerging earlier, the fatter dormice used their extra reserves to increase their metabolic rate more frequently and spend more time at normal body temperature during hibernation. This strategy seems to enable dormice to minimize the negative effects of torpor while maximizing the total hibernation time.

Why should animals prefer to hibernate underground when outside temperatures would allow them to forage without energetic constraints? The researchers explain this with a beneficial side-effect of hibernation: hidden underground, dormice are not easily found by predators and thus have a higher chance of survival. As long as the dormice do not have to emerge to find a partner and reproduce, they are better off in their subterranean hideouts. A broader implication of the result is that climatic conditions are not the only factor that influences the duration of hibernation. Climate change could therefore affect hibernators quite differently from how we might expect.


'/>"/>

Contact: Susanna Kautschitsch
susanna.kautschitsch@vetmeduni.ac.at
43-125-077-1153
University of Veterinary Medicine -- Vienna
Source:Eurekalert  

Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Fat and fit
(Date:1/26/2017)... CITY , Jan. 26, 2017  Crossmatch, a ... unveiled a new solution aimed at combatting fraud, waste ... solution was introduced at the Action on Disaster Relief ... key meeting point for UN agencies and foreign assistance ... Fraud, waste and abuse are a largely unacknowledged ...
(Date:1/23/2017)...  The latest mobile market research from Acuity Market ... The quarterly average price of a biometric smartphone decreased ... 2016.  There are now 120 sub-$150 models on the ... just 28 a year ago at an average price ... Most , Acuity Market Intelligence Principal, "Biometric Smartphones are ...
(Date:1/18/2017)... MedNet Solutions , an innovative ... spectrum of clinical research, is proud to announce ... the organization in terms of corporate growth, outside ... and services. The company,s exceptional achievements can be ... iMedNet ™ – MedNet,s ...
Breaking Biology News(10 mins):
(Date:2/16/2017)... , Feb. 16, 2017  Dermata Therapeutics, ... products to treat a variety of dermatological diseases, ... Series 1a financing and entered into a $5 ...  Dermata intends to use the capital for general ... major advancements in the treatment of serious diseases ...
(Date:2/16/2017)... ... February 16, 2017 , ... AxioMed announced today the success ... trained surgeon, completed the procedure on Monday, Jan. 30 at Andrews Memorial Hospital ... suffering from degenerative disc disease with radiculomyelopathy, as a result of degenerative cervical ...
(Date:2/16/2017)... Feb. 16, 2017  Rhythm, a biopharmaceutical ... deficiencies that result in life-threatening metabolic disorders, ... million mezzanine round of financing with existing ... Capital, New Enterprise Associates, Pfizer Venture Investments, ... healthcare investment fund. Rhythm will use the ...
(Date:2/16/2017)... ... February 16, 2017 , ... ... Inc. has further extended its industry leading Biochemistry Services specifically targeting the ... cGMP techniques and methods for the biochemical and biosimilar characterization , ...
Breaking Biology Technology: