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Pinky mice as food

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carlos

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Hi, is that a good ideas to provide pinky mice as food for the amphibians? I want to try to feed them for pinky mice but I heard some information about that is not a good food for the amphibians. So, I want to do some research before I try to do so. Thank YOu!
 
E

edward

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pinks are calorically dense when compared to other commenly used food and can very easily be offered too often leading to obesity and other problems. For example a pink the same size as a adult domestic cricket weighs at 4 times as much as the cricket.
In addition, commecial rodent chows are typically high in vitamin A and can lead to calcium metabolism problems as vitamin A competes with vitamin A for uptake.

Ed
 
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carlos

Guest
Hi Ed, thx for your information
happy.gif


Anythings can provide enough D3 and calcium If I not feed pinks as food ?
happy.gif
 
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jameswei

Guest
i heard butterworms are calcium rich. Perhaps you might want to look into that. I think so long as you gutload your insects, worms, whatever with a decent amount and sprinkle them with the recommended vitamin supplements they will be find.
 
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carlos

Guest
Hi,
Can I use the uvb5.0 can provide D3 for the amphibians?
 
E

edward

Guest
I am not entirely convinced that butterworms are high in calcium per se as the units provided are a volume measurement and cannot be converted and compared. In addition, the ratio of calcium to phosphorus needs to be determined because as long as the ratio of calcium to phosphorus is less than 1 to 1 there is not sufficient calcium in the diet.

Almost any vitamin/mineral supplement that uses betacarotene as the source of vitamin A and has a calcium to phosphorus ratio between 1-1 and 2-1 is fine.

Typically it appears that caudates are efficient at metabolizing calcium and anecdotally appear to not need supplementation that often but disruption of calcium metabolism has been seen in axolotls fed mainly on pinks.

As caudates tend to be photophobic the use of lights is of limited value.

Ed

(Message edited by Ed on July 02, 2005)
 

findi

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pinks as food

Hi Carlos,

In addition to what has been posted re pinks:

Over the years I've seen a number of problems arise from feeding pink mice to (mainly insectivorous)amphibians and reptiles, especially fatty deposits in the cornea and liver problems. Most common in tiger salamanders, White's treefrogs, basilisk, marine toads, as I remember. These all take an occassional mammal in the wild (although studies of B. marinus in Venezuela indicate this is very rare for them) but never as a regular part of their diet. Crayfish (de-clawed to be on safe side) are a great calcium source for large amphibs. and cause no problem as a regular dietary item for American bullfrogs, marine toads, mudpuppies, amphiuma in my experience - minnows are much better than mice also.

Re UVB, too much can cause eye problems in some species - has been noted in gray treefrogs, others per a recent article - even the amount in "plant lights" was detrimental to gray treefrogs that perched in the open, close to the light - many amphibs have UVB protectants in the skin as well, so likely not designed to use it to synthesize Vit. D.

Best, Frank
 

blueberlin

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***reviving topic***

There is a sort of "opinion" circulating over here on my side of the pond that an amphibian (well, axolotls, to be specific) cannot properly digest mice, cannot properly draw nourishment from them. Is there any evidence to support or refute this assumption?

Thanks in advance for all help,

-Eva
 

Kal El

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G'day Eva,

I have often pondered on the same question, but am yet to come up with any definitive answers.

The only thing I could think of is that axolotls lack (or have very little) the necessary enzymes to metabolise such tissue. It's kind of like how humans cannot digest celloluse (i.e. grass) because the appendix doesn't produce a specific and functional enzyme to do so. Granted that the grass will be digested within the stomach because of high level of acidity (hydrochloric acid), there won't be any nutritional value absorbed. Not to mention, it will also taste particularly awful :p

Hopefully somebody else can chime in with a more definitive answer ;)

Jay.
 

blueberlin

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Yes, I understand that that is also how it works with vegetable matter for axolotls (I hesitate to apply this to all salamanders or amphibians). I just don't understand how it could apply to mammalian foodstuffs - organ meats and chicken breast seem to be accepted as viable food options, right? If so, I would think a "pinky" even more nutritious because it is an entire organism, not just a piece of one.

Disclaimer: I understand the danger of obesity and fatty deposits in organs. Am just curious about the possibility of absorbing nutrients from a mouse/mammal.

-Eva
 

Azhael

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I personally think that mammal flesh in any of it´s forms is not a suitable food for caudates. I only used it once, on a desperate time, and after checking how the feces came out i will never use it again. I seriously think(but have no real proof of it) that they cannot digest it properly. Perhaps they digest parts of it, probably the fat parts, but the tissue, the muscle, i think it´s virtually excreted untouched.
 

BILLY JAMES

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Hi all
A couple of years ago when I sold my snakes I had a lot of pinky mice left over, so I feed them to my axolotls over a couple of months and all parts were digested with no problems. Not that I am suggesting pinky mice are a good diet but short term my axolotls had no ill effects.
 

IanF

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I'm not going to get into anything complicated but I just felt I'd share that my Tiger Salamander is perfectly capable of digesting cut up pinky mice, at least it looks digested to the eyes. As for are they good as an occasional treat, I'd say only if you needed to bulk them up and even in that case waxworms would do the same job I'd think. Anyway, just my two cents.
 

Abrahm

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To address your specific question, Eva, I think amphibians can digest mammalian tissue fine. The process of breaking down proteins, lipids and the majority of carbohydrates are facilitated by a handful of highly conserved proteins. They show up in most animals and there function is only to break down certain bonds. Most proteases (protein digesting enzymes) split proteins at specific points such as between certain amino acid linkages and are facilitated by high pH environments and since we use the same amino acids as amphibians and most other life there really shouldn't be any problem with digestion.

This is even supported above by Ed's comments (Ed is an experienced zookeeper with an impressive base of scientific knowledge) that mammalian tissue is calorie dense, hence an amphibian can derive an impressive amount of usable energy from a mammal food item. That is why these items can easily lead to obesity.

I think some of the very real problems of feeding an unregulated mammalian diet have led to this sort of legend popping up. In these "I heard it on the net" days I think a lot of people get handed information and end up making their own reasons for why such a thing is common knowledge. Thinking they don't have any nutritional value seems to be an easier thought than they are calorie dense and may result in hypervitaminosis (from the high levels of the fat soluble vitamin A in commercial rodent foods.)
 

Kaysie

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I've fed pinkies to all of my large caudates on a fairly regular basis (usually 1 every 6-8 weeks or so). I've never noticed any problems with their digestion.
 

blueberlin

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Hi all,

Thank you so much for your answers. Abrahm: excellent, this is the kind of info I need. Right now opinion is about 10:1 that pinkies can't be digested, so I want to make sure I understand what I'm reading here before I try to translate it into German.

Let's see if I've got it right. Digestion is the breaking down of proteins, lipids (fats), and carbohydrates. Animals digest using a few special proteins and enzymes that split the proteins (of the food) at specific points, such as between amino acids - amino acids being the "building blocks" of proteins. Since animals all have the same amino acids, the digestive process will not distinguish between, say, mouse or grasshopper or fish proteins. Plant cellulose (a carbohydrate) cannot be digested because the carnivore does not have the enzyme necessary for splitting the carbohydrate into something that can be absorbed.

Is that all correct?

-Eva
 

Jan

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In a nutshell that is correct for most carnivorous animals. Cellulose is one constituent of the plant cell wall and is a polysaccharide. Carnivores in general digest saccharides quite inefficiently (compared to omnivores/herbivores)....very basically, carnivores lack the proper dentition, gut flora and enzymes necessary to digest cellulose. Cellulose (fiber) and other non-digestible materials such as chitin and bones that are not destroyed by stomach acid are passed into the feces.

I would agree that most caudates can digest animal material as they are carnivores. However, in that their natural diet is composed of invertebrates, other than for specific dietary reasons and to avoid the risks that have been outlined, I would wonder why we would not advocate minimizing their (pinky) use as a food source for caudates? In the wild, would axolotls have many chances to eat pinkies?
 

Abrahm

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Is that all correct?

-Eva

As my understanding goes, that is correct. I've studied quite a bit of molecular biology/biochemistry in school but I am by no means an expert. Since all animals need to make use of protein they have the biochemistry necessary to digest those proteins into usable amino acids. The proteins work by working on certain contents of molecular structure, such as trypsin cleaving between lysine and arginine. Essentially the same case stands for lipids.
 

blueberlin

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In a nutshell that is correct for most carnivorous animals. Cellulose is one constituent of the plant cell wall and is a polysaccharide. Carnivores in general digest saccharides quite inefficiently (compared to omnivores/herbivores)....very basically, carnivores lack the proper dentition, gut flora and enzymes necessary to digest cellulose. Cellulose (fiber) and other non-digestible materials such as chitin and bones that are not destroyed by stomach acid are passed into the feces.

I would agree that most caudates can digest animal material as they are carnivores. However, in that their natural diet is composed of invertebrates, other than for specific dietary reasons and to avoid the risks that have been outlined, I would wonder why we would not advocate minimizing their (pinky) use as a food source for caudates? In the wild, would axolotls have many chances to eat pinkies?

Sorry - I'm not advocating the use of mice as caudate food. I can't really see the purpose of doing so, either, considering how many different types of things they can eat, how easily available those things are, often in your own back yard, and how much more appropriate they seem to a naturalistic diet. I'm just trying to clarify whether or not caudates are able to digest a mouse (which also leads me to question the digestion of beef, chicken, etc.).

Now, though, I am also curious as to whether feces from eating a mouse would include bones and if not, why not? Answers spawning questions...

-Eva
 

Kal El

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G'day Eva,

Firstly, I would to thank you for raising this topic because it has certainly answered my queries :happy:

blueberlin said:
Now, though, I am also curious as to whether feces from eating a mouse would include bones and if not, why not?

Pinky mice are low in calcium (conflicting answers) because they are developing and therefore have not fully formed calcified bones. However, as they grow, I'd imagine that the Ca will increase in the Ca:p ratio.

Personally, I think the bones will come out the same the way they went in. I mean, there may be some 'splintering' of the bones due to the pH in the stomach, but I wouldn't expect it to be completely digested. To be honest, I'm basing this on the disgestion of a mealworm's exoskeleton. In the past, I've noticed that every time I fed my axolotl mealworms, there would be chitin floating on the surface of the water.

So, my reasoning is that if an axolotl can't properly digest a mealworm's exoskeleton, it would surely have greater difficulty in digesting calcified bone.

But, hey, I'm just as curious as you are!

Jay.
 
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