Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pythons can be couch potatoes, too

26.08.2002


UCI researchers find that consumption of certain food types cause the constricting reptile to expend excessive energy in digestion



Gary Larson, creator of "The Far Side," is noted for morphing animal scientific attributes into human behavior in his comic strips. Consider the sketch of a family of pythons lying about after Thanksgiving dinner. The snakes that consumed a mouse, some chicken and glucose are ready to go out and play football shortly after dining. But the pythons that indulged on the starchy foods cannot budge from the couch, still trying to digest their meal.

A scene from a Larson cartoon? Perhaps. But it is also a notion based in scientific fact.


A team of UC Irvine researchers has found that pythons use significantly more energy to digest proteins than they do carbohydrates, revealing that metabolic rates needed for digestion are based on the content of the food instead of the volume. The findings also provide more information on understanding how other animals - and humans - metabolize food and the importance of their diet.

Marshall McCue, Albert Bennett and James Hicks, researchers in the Department of Ecology and Evolutionary Biology at UCI, will present these findings at the American Physiological Society intersociety meeting on Tuesday, Aug. 27, in San Diego, Calif. The researchers tested pythons to determine the reptiles’ specific dynamic action (SDA), which is the metabolic increment associated with a python’s digestion, assimilation and excretion of specific foods. SDA is determined not by how much a python eats, but what it eats. Moreover, the energy required for a certain level of SDA accounts for a large energy expenditure that may reduce the energy available for other activities. The researchers used pythons because their metabolic rates vary drastically from when they are at rest, to when they are digesting.

Hatchling Burmese pythons were raised in the laboratory on a diet of mice and rats for four months prior to experiments. The pythons were then fed various meals of proteins, carbohydrates and lipids. Protein meals consisted of lean chicken breast meat, casein, collagen and gelatin. Carbohydrate meals included two complex (wheat starch, cellulose) and two simple carbohydrates (D-glucose, sucrose). Lipid meals consisted of lard and beef suet. Meal volumes were varied and feeding treatments were randomly assigned to each individual python.

The post feeding metabolic responses for each of the 11 experimental meals were combined and compared with their standard metabolic rate.

The key findings from this experiment were:


Mean masses of eight pythons before and after experiment did not change significantly.

Mouse, chicken, casein, collagen, glucose and sucrose meals induced an SDA response; gelatin, suet, lard, cellulose and starch did not induce SDA.

SDA responses induced by meals with the largest and smallest volumes were not statistically different;
intermediate meals induced the greatest SDA.

Gelatin appeared to be assimilated but did not cause a significant SDA response.

Collagen caused an SDA response; however it was always completely regurgitated several days following ingestion.

Protein meals that induced the greatest SDA (casein, mouse, and chicken breast) were also those highest in essential amino acids.

The results revealed that single and dual element sugars caused the pythons’ metabolic rate to increase two-fold. However, complex carbohydrates were unable to elicit a significant metabolic response and were not assimilated by the snakes. Protein meals caused variable SDA responses that appeared to be related to the amino acid composition of the specific meals. Casein caused a four-fold increase in metabolism, while gelatin caused no detectible changes and was not assimilated. Various lipid meals did not cause any significant change in oxygen consumption and were generally not assimilated.

The findings suggest that a large serving of one particular type of food probably does not trigger the large SDA increment well known in this species. The researchers’ next steps are to investigate SDA induced by specific amino acids and amino acid mixtures and digestive assimilation efficiency of meals that induce SDA.

Essentially, pythons are governed by physiological principles that encourage consumption of specific foods to optimize their metabolic rate and to allow energy expenditure for activities other than digestion.

Tom Vasich | EurekAlert!
Further information:
http://www.the-aps.org/publications/journals/tphys/2002html/Aug02/compmtg/online_program.pdf
http://www.the-aps.org/meetings/aps/san_diego/home.htm
http://www.today.uci.edu

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>