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Lactic Acid in Amphibians
#1
I took a small amount find some publicatations relating to lactic acid buildup in amphibians and it's implications. I'll post the articles and/or links as I find them with the quoted text.

"Amphibians use aerobic pathways for most activity
and switch to anaerobic glycolysis for heavy activity.
During anaerobic activity, the muscles fatigue rapidly
due to the buildup of lactate due to an increase in the
level of free hydrogen ions in the muscle. These
hydrogen ions in turn create acidified inorganic
phosphorus ions, such as H2PO4, which are known to be
a proximate cause of fatigue in amphibians. Many
amphibians may struggle a few minutes before
collapsing. An amphibian oxidizes lactate at a rate about
nine times slower than an equivalent-sized mammal so it
may take hours to recover from a fatiguing event. Critical
patients may need elevated levels of atmospheric
oxygen before and after handling.
The role of lactate in acid-base metabolism in
amphibians has been poorly investigated. The pH of
amphibian blood can vary widely in normal specimens.
Since we do not understand the actual way that
endogenous lactates are completely eliminated in
amphibians or even have a full understanding of the
physiology of metabolic acidosis or alkalosis, it seems
prudent to avoid adding sodium lactate (found in lactated
Ringer’s solution) or using other lactated buffer solutions
as fluid therapy for amphibians. Amphibian Ringer’s
solution, described previously, is one of the most
effective fluids for managing amphibians. If that is not
available, 0.5 to 0.6% saline solution (ie, 5 to 6 g table
salt per liter of water) is approximately isotonic for
amphibians. "

http://www.cabi.org/isc/FullTextPDF/200 ... 121846.pdf
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#2
I have also read a papers that shows that high lactic acid levels in the frogs blood can lead towards low calcium levels, which then lead to the muscles becoming lethargic, and in many cases, they frogs start seizing. The same lactic acid levels can cause bone density loss as the h+ ions start drawing away all available base sources.

Here is another good read:

Under normal activity levels, energy production in the amphibian is produced primarily by aerobic metabolic pathways, while outbursts of unusual activityare sustained by anaerobic metabolic pathways (Gatten et aI., 1992; Pough et aI., 1992). Amphibians that make explosive escape attempts, such as ranids, utilize anaerobiosis for this activity and quickly fatigue
with the buildup of lactate (any salt derived from lactic acid) in the muscle tissues. Thus those amphibians with a low aerobic scope may suddenly collapse during physical restraint or during capture attempts. The sustainability of this anaerobic activity is brief, oftenlasting less than 2 minutes. Other amphibians, such asbufonids, have a high aerobic scope and can put up acontinuing struggle with minimal signs of fatigue.There is a strong correlation between an amphibian's hunting techniques and its aerobic scope. Sit and wait predators (e.g., ranids, ceratophryne leptodactylids)have a low aerobic scope while active foragers (e.g.,bufonids) have a high aerobic scope. There may be marked differences in the aerobic scope between age classes of a given species, with young specimens having a lower aerobic scope (Taigen & Pough, 1981).

Recovery from fatigue varies among species, but the rate of oxygen consumption appears to be one of the main limiting factors (Gatten et aI., 1992). The clinician should avoid exhausting the critically ill amphibian patient through excessive handling. Slightly elevated levels of atmospheric oxygen for several minutes prior to and immediately following handling is recommended for the critical patient. Bubbling oxygen through water used to moisten the amphibian patient may help speed recovery. Typically, amphibians return to resting values of oxygen consumption within an hour of exercise-induced exhaustion (Gatten et aI., 1992).

The majority of the energy for nonsustainable exercise in amphibians occurs via glycolysis. As glycogen is metabolized, the concentration of lactate in themuscles rises whereas succinate, pyruvate, and other metabolites are relatively unaffected. Total-body lactate can take several hours to clear from an amphibian's system. The metabolism of lactate has beenpoorly studied in amphibians, but what little is known indicates that it is very different from lactate metabolism in mammals. In one experiment to determine the fate of lactate, specimens of the American toad, Bufo americanus, were exercised and treated with radioactively labeled lactate and glucose (Withers et al.1988). Where as mammals subjected to similar experiments oxidized the majority of the lactate (up to 950/0 ), the toads oxidized less than 100/0 of the la beledlactate. Excretion of lactate is limited in amphibians.The lactate level in the urine of amphibians is extremely low, if present at all, and the gills or skin playseemingly insignificant roles in eliminating lactate from the aquatic amphibians studied.

Although increased levels of blood lactate do not appear to directly correlate with muscle fatigue in amphibians, it is known that lactate plays a role in the dvelopment of fatigue in amphibians, probably due to itscontribution to the level of free hydrogen ions in themuscle. The hydrogen ions contribute to the development of acidified inorganic phosphorus ions, such as H2P04, and appear to be the proximate cause of fatigue in amphibians and mammals (Gatten et aI., 1992).

The scarce amount of information on lactate and acid-base metabolism in amphibians has been scarcely addressed compared to the volume of material devoted to mammals. The pH of amphibian blood can vary widely in normal specimens, and although compensatory mechanisms appear similar in amphibians and mammals, the exact nature and contribution of the different mechanisms are not well understood inamphibians (Boutilier et. aI, 1992; Shoemaker et. aI,1992). Given that the fate of endogenous lactates is poorly understood in amphibians, as are the compensatory mechanisms for dealing with metabolic acidosis or alkalosis, the clinical use of sodium lactate(found in lactated Ringer's solution) is not advisable in amphibians

http://www.scribd.com/doc/62500589/Amph ... -Husbandry
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#3
More good reading:

http://mit.biology.au.dk/zoophysiology/ ... dersen.pdf
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#4
Justin thankyou for the time taken on this!!Fascinating reading, extremely interesting and enlightening,much appreciated
regards
Stu
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#5
Bottom line seems to be that we need to keep our frogs as stress free and exhaust free as possible. Makes sense.

Lactic acid build up has been an issue with all sorts of animals.
When fighting salmon , which travel long distances and fight to go up currents naturally, we can fight them for long periods of time and later release them , if wished.
Ambush predators , as opposed to salmon, like pike and muskie need to be brought to the boat much quicker to ensure a good release because they were never made to fight as salmon, and lactic acid build up occurs much sooner than in salmon .

Rich
Darts with parasites are analogous to mixed tanks, there are no known benefits to the frogs with either.


If tone is more important to you than content, you are at the wrong place.

My new email address is: rich.frye@icloud.com and new phone number is 773 577 3476
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#6
I translated this on google, just gibberish in polish. Spam!!! Do not click on ANY links!!!
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