Feuersalamander Infoboard

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Original von Kichwa
Wenn die Tiere in unseren Breiten, in denen es mitunter vorkommt, dass tagelang Minusgrade herrschen und zentimeterhoch Schnee liegt, leben - dann ist das doch schon ein Beweis oder?

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Original von SiLL
Es gibt aber auch extreme die überaus kälteunempfindlich sind. Es gibt einen Molch/Salamander der enorme Minustemperaturen verträgt(...). Ich weiß leider nicht mehr wo ich den Artikel hatte....Ingo????

Zitat

Freeze-tolerance in Salamandrella keyserlingii (MASTER'S THESIS)
Mette Jensen

It has been estimated that Salamandrella keyserlingii can tolerate freezing to as low as -35 deg.C, which establishes the species as the presently most freeze-tolerant vertebrate. No solid scientific documentation is available which confirms this assertion.

The purpose of this study was to document the freeze tolerance of this species and investigate the underlying biochemical and physiological defense mechanisms. In total, four experiments were carried out: 1) determination of lowest lethal temperature (LLT), 2) determination of ice content (cooling rate: -0.06 deg.C/hr) in the interval -1 to -5 deg.C), 3) dehydration tolerance, and 4) determination of glycogen, glucose, glycerol, and lactate in liver, muscle, skin, eggs/testicles (cooling rate -0.06 deg.C/hr to -2 and -5 deg.C, respectively).

1) It was found that cooling rate, inoculation conditions, and state of nourishment are factors of great consequence concerning survival and reconvalescence of the organism when subjected to freezing. It was determined that S.keyserlingii tolerates freezing down to -15.3 deg.C (cooling rate -0.06 deg.C/hr) at which temperature the organism was maintained for 24 hours.From the inset of exotherm to the conclusion of the experiment, the organism has been frozen for more than 11 days. no organisms survived cooling to -17 deg.C, which is presumably accountable to deterioration in their state of nourishment/physical condition as experiments were carried out in late January.

2) The relation between ice content and the freeze end-temperature was best described by a saturation curve in which approx. 60% of the bodily fluids were frozen at -5 deg.C.

3) The maximum dehydration tolerance (49.9+/-2.3% of total water content) wasa independent of respiratory surface area.

4) All accumulation in the liver was exclusively glucose (up to 216+/-21.5mg/g (dw)) while the remaining tissues accumulated both glucose and glycerol (up to 38.2+/-7.27 and 78.5+/-31.2mg/g (dw), respectively) under freezing conditions. In muscle, skin, and eggs/testicles, lactate contenty increased during freezing, while increase in the liver was minimal.

It is hereby documented that to this day, S. keyserlingii is the vertebrate which has exhibited the greatest degree of freeze tolerance.

Zitat

Original von Inshi

@ Andy W.: Auch hier gilt: Do NOT try this at home!!!

Viele Grüße,

Ingo

Zitat

Hehe, I guess one could conceivably take a 10-year break from the hobby, and then restart in 2014 with the same animals