Navigation Links
A frog's life is food for thought

Starvation, malnutrition and re-feeding can have deadly consequences for humans and most animals but not Australia's green-striped burrowing frog.

PhD student Rebecca Cramp from The University of Queensland has found that unlike most animals, which can't digest food after long periods of starvation, the green-striped burrowing frog is able to absorb nutrients 40 percent more effectively after 3 months without food, than frogs that had eaten regularly.

"They can take massive meals equivalent to 50 percent of their body mass and maximise their digestive capability from the outset," Ms Cramp said.

Little is known about the effects of prolonged food deprivation on the gut of animals that go without food for long periods. Ms Cramp's study is helping explain why animals such as the green-striped burrowing frog are able to gorge themselves on huge meals without overwhelming their digestive system.

"Nothing was known about their digestive physiology when I first started this project and for an animal that can starve for up to four years it is really interesting when you relate that back to human starvation," she said.

"There is no way a human could last for four years without food."

Green-striped burrowing frogs spend upwards of 10 months of the year in underground burrows in a hibernation-like state known as aestivation. During this time they do not feed and survive on fat reserves.

The frogs return to the surface after heavy rain, sometimes for as little as a week - to find food and build up fat reserves.

During the study Ms Cramp and her supervisor Professor Craig Franklin from the School of Integrative Biology collected frogs from areas west of the Great Dividing Range, including Dalby and Goondiwindi.

They brought the frogs back to the laboratory where one group was kept in aestivation while the other group were not allowed to aestivate and were fed regularly.

"I compared the various aspects of their gut biology and physiology," she said.

"We put animals into aestivation and woke them up and fed them to find out how quickly they got everything going again."

Ms Cramp's results show that animals can maintain the functional capacity of the gut during aestivation despite significant energetic cost, allowing them to digest food as soon as they resurface from aestivation.

"Despite the marked decrease in absorptive surface area of the gut of aestivating frogs, they appear to actually increase their absorptive capacity during aestivation," she said.

"Within 36 hours of the ingestion of the first meal the gut had all but returned to its pre-aestivation state, and by the completion of digestion of the first meal the gut was operating on par with that of non-aestivating frogs," she said.

"This rate of rectification of gut morphology is virtually unparalleled with the small intestine having increased in mass by 450 percent within just 36 hours."

The results of Ms Cramp's study could have important implications for human survival.

"Human survivors of starvation can endure the horrific and often fatal effects of re-feeding after starvation, including massive diarrhoea and gastric ulcers," she said.

"Science still understands very little about why that occurs and what can be done about it."

Ms Cramp said scientists originally thought that during aestivation frogs would shut down all non-essential energy consuming processes. Her results contradict this theory.

"It was really interesting to us that they do not appear to shut down the functional aspect of their gut biology," she said.

"It is important that they are able to eat and digest from the first meal because they are only up for as little as a week at a time before they have to go back down again."

The results of the study were featured in a recent edition of Science magazine and form the basis of Ms Cramp's PhD study, from which she hopes to graduate in July.


'"/>

Source:Research Australia


Related biology news :

1. Different microarray systems more alike than previously thought
2. Atmosphere may cleanse itself better than previously thought
3. Lifes origins were easier than was thought
4. Alleged 40,000-year-old human footprints in Mexico much, much older than thought
5. Deep-rooted plants have much greater impact on climate than experts thought
6. Avian flu transmission to humans may be higher than thought
7. The diversity of marine life in the Gulf of Maine region is much greater than previously thought
8. Memory loss affects more of the brain than previously thought
9. Brain works more chaotically than previously thought
10. Liver regeneration may be simpler than previously thought
11. Anthrax attack posed greater potential threat than thought
Post Your Comments:
*Name:
*Comment:
*Email:


(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:1/21/2017)... Jan 20, 2017 Research and Markets has ... 2017-2021" report to their offering. ... The global voice recognition biometrics market to ... The report covers the present scenario and the growth ... calculate the market size, the report considers the revenue generated from ...
(Date:1/19/2017)... PUNE, India , January 19, 2017 ... Sensor Market, Opportunities and Forecast, 2014 - 2022," the global biometric sensor ... of 9.6% from 2016 to 2022. In 2015, Asia-Pacific ... for both public and private sectors. Continue Reading ... ...
Breaking Biology News(10 mins):
(Date:1/23/2017)... , Jan. 23, 2017  Spherix Incorporated (Nasdaq: ... committed to the fostering of technology and monetization of ... patent infringement lawsuits. Anthony Hayes , ... 2017, we will continue to communicate with shareholders about ... and our due diligence on other patent assets that ...
(Date:1/23/2017)... 23, 2017  Alkahest Inc. ("Alkahest"), a biotechnology ... diseases and other age-related conditions, announced today that Sam ... Chief Medical Officer. In this role, Dr. Jackson ... at Alkahest and serve on the Executive Leadership ... as Executive Director at Dynavax, where he led the ...
(Date:1/21/2017)... ... January 21, 2017 , ... Nova Oculus Partners has ... pioneering medical device for the treatment of Age-Related Macular Degeneration. , The company’s ... global regulatory consultancy that helps companies like ours secure government approvals for their ...
(Date:1/20/2017)... ... January 20, 2017 , ... The two newest companies to join ... patients. Vironika, a spin out from The Wistar Institute, and Sanguis, launched by a ... 3624 Market Street. , Vironika is developing a treatment for a chronic viral ...
Breaking Biology Technology: