What is the physiology behind pyramiding?

[lilacdragon]

Hmm...

I agree with Team Gomberg, I don't think anyone here is deliberately promoting high growth rates, i.e., recommending "power feeding" or whatever. And I hardly think that anyone is promoting "intentionally growing them slower by starving them, dehydrating them, and keeping them cold and dark throughout the year", either. That is an insulting insinuation.

I think Tom has summed up his position rather well in one of his last couple of posts, when he said:

Using "un-natural" captive techniques to counter "un-natural" captive shortcomings makes perfect sense, AND it works very well if done correctly. ....... the desiccating heating elements that do not exist in the wild, .... are necessary in our captive indoor environments. So yes, I do offer a humid hide with higher humidity than what my russian tortoises are likely to encounter in the wild every day. I do it because I also offer them a desiccating light bulb to warm up under when they are indoors, which they would also not encounter in the wild.

Now there is a certain logic to this. Dealing with a problem by alleviating its symptoms does not mean you have solved the problem; but you have put "sticking plaster over the wound" and it's often the best we can do. I think Tom is acknowledging this, and he is presenting us with what he has found to be good "sticking plaster" for certain problems with growing Sulcatas....

The honest truth is that there is no way that we can ever completely remove the problems inherent in keeping a species in an environment it has not evolved to live in. The animal is "not meant to live here".
We can only (a) decide that it is wrong to keep an animal outside of its natural habitat (which is a perfectly reasonable conclusion) or (b) work towards finding the best alternative environment that the animal can cope with, and which is within the owner's capabilities and resources.

(b) will inevitably mean applying sticking plaster over a certain number of as-yet unsolved, and possibly insoluble problems.
I think Testudoresearch is right that there are going to be long-term health issues which are not at all obvious in the first decades, maybe the first half-century of life, when animals are taken out of the environment they evolved to inhabit, and so many factors are altered.
To take an example I am more familiar with: Can you think of a way of providing an indoor pet reptile in a vivarium with a "sun" that rises, moves across the sky and sets at a slightly different time each day, changing its UV and visible spectrum and creating polarisation patterns in the sky as it does so? And if you could, would you refuse to sell any reptile to anyone who can't afford the "solar simulator"?
But reptiles, like many other animals, use the sun to set their circadian and circannual rhythms, which govern all their neurological and endocrine pathways.. seasonal changes, activity levels, and basking behaviour.... A tortoise that is living in artificial day/night cycles with no seasons, no rest periods, no real sunlight will not have normal physiology. It appears "normal" and seems perfectly "healthy" ... but will that abnormal physiology alter its susceptibility to stress, infection, metabolic disorders or cancer, in later life?
I don't know. But I know that there's a huge burden of disease in humans that's increasingly being ascribed to our "civilised" way of life, far from the outdoor lifestyle of our ancestors, who were tied to day/night cycles and seasonal unprocessed foods. We all seem "healthy" but our circadian rhythms are messed up, there is a pandemic of vitamin D deficiency, and in later life there's a huge and ever-growing number of people developing seasonal affective disorder, auto-immune diseases, obesity, heart disease, diabetes, osteoporosis, cancers....

Fortunately, the animals we choose to keep are some of the most resilient creatures on the planet, surviving in some of the most inhospitable places on earth. I think this is why somehow so many survive the most inexpert care... and why those people who do offer their animals expert care, care a great deal about them, like Tom and Testudoresearch, who I suspect have very different opinions regarding my (a) and/or (b)....

But I digress. The topic was "food and growth rates"...
Free unlimited access to food throughout early life is inevitably going to increase growth rates over those which a perfectly healthy youngster in its own habitat, in the best of years, would achieve, even without parasites, predators etc. It is a technique used in "headstarting" re-population programs worldwide, for rearing baby reptiles of highly endangered species so that they will be big enough to have a better chance of survival than wild babies would have done, at the time of release.
And finely powdered meal is highly digestible compared to coarse fibrous pellets and the even coarser Pro Alpin or whatever. So that will also increase growth rates. If it contains cereals then there will be starches and sugars, not found in wild diets, which are rapidly digested too.
So the type of food offered, and the period it is offered for, will "promote high growth rates" whether the owner knows and wants this, or not....

Frances

p.s. Has anyone looked at the X-ray of Sulcata Sandy's tortoise, in the last post on the previous page?

 

[Testudoresearch]

Growth and body composition in captive Testudo graeca terrestris fed with a high-energy diet. The diet in the study was exclusively composed from a commercial canned, vitamin-enriched cat food(Tuffy’s, Heinz Pet Products, Kentucky, USA). 78 g of cat food was blended with22 g starch (corn flour), to dilute the excess protein with a high carbohydrate. However, the breeding activity was attained at about 170 wk in males and 230 wk (4 years) in females. The authors concluded that growth and maturity were highly accelerated in Testudo graeca terrestris, without symptoms of disease, by providing them with a high energy protein-balanced diet.

It helps if you are familiar with the full paper and its conclusions before citing it.....

This is what it actually says. I have it in my library.


"the achievement of rapid growth were found to result in three syndromes in growing tortoises: soft shell (osteomalacia) (Wronski et al., 1992; Homer et al., 1998); lumpy shell (pyramiding), due to insufficient calcium and phosphorus; and gout (uricacidaemia), as a result of excessive protein intake (Scot, 1992). A high protein diet was suggested to solve soft shell and lumpy shell syndromes, but this diet frequently caused gout and eventual death in growing tortoises. This was also our experience in initial trials: A vegetarian diet produced the soft shell syndrome and high mortality of hatchlings, even when reared in the open exposed to natural sunlight; a high protein diet alleviated soft shell but resulted in gout and therefore also a high rate of mortality"

The methodology of this study was also seriously flawed (a common trend). One failure was the use of a glass greenhouse. Glass blocks UVB... duh! They also used an infra-red, not UVB generating lamp. Double duh! They claim "tortoises experienced a natural humidity" - but had the windows closed some of the time and in any event the humidity in a greenhouse, even with the windows open is invariable different than that outside (measure it yourself - they didn't), and the real 'killer'? The "vegetarian diet" used was lettuce and tomato! No supplements or other source of calcium used. Does that qualify for a triple "Duh!"?

It is a wonderful example of some of the really poor work relying on abysmal methodology, and drawing completely the wrong conclusions, that manages to get itself published. Just because it is published does not mean it is true.....

Assessment of dual-energy x-ray absorptiometry for use in evaluating the effects of dietary and environmental management on Hermann's tortoises (Testudo hermanni). The neonates kept in group 1 housed in an artificial setting and fed naturally growing vegetation were prone to develop pyramiding than group 2 housed housed in an artificial setting and fed vegetables grown for human consumption. The natural-housed control group had the shell with the lowest BMD(bone mineral density). The difference in BMD of captive-raised tortoises and control tortoises in the study could have been secondary to the environment, apart from the diet. In the authors’ opinion, the environment may have been responsible for the variations in BMD in 2 ways. The authors also speculated that excess calcium in Hermann’s tortoises is primarily deposited in the carapace bones. This exaggerated deposition could result in pathological morphological consequences (ie, pyramidal growth).

I have read that one too. Again, you have (some pretty obvious) variables not taken into account, and quite a bit of speculation with zero supporting evidence. Their main intent was not to grow nice tortoises (so they did not put much thought into that) but instead, to look at x-ray techniques. They showed certain x-ray techniques are useful. They did not discover much about tortoises....

So, what were roles of animal matters or high protein and the vegetables for humans in the above prospective studies that have been conducted for more than 2 years on the neonates? To promote pyramiding?

Quoting from the first study:

lumpy shell (pyramiding), due to insufficient calcium and phosphorus
gout (uricacidaemia), as a result of excessive protein intake
a high rate of mortality

All of which is 100% predictable and was described years ago.

IMHO, the tortoises in our enclosures were no more wild animals but pets

Are you suggesting that their nutritional and environmental needs are somewhere different? How? Just because you remove them from the wild for a couple of generations has no effect whatsoever on either...

Their needs are identical.

---

p.s. Has anyone looked at the X-ray of Sulcata Sandy's tortoise, in the last post on the previous page?

Difficult to get a totally accurate analysis with that image size/resolution, but the pelvic and limb bones appear well formed and of acceptable density. The carapace mineralization appears (to me) to be possibly a little bit on the 'light' side. It is not gross, however and may not be significant. I would not like to reach a firm conclusion from that one image. There is nothing there that I can see that suggests anything seriously wrong. The eggs appear well-calcified.

---

I agree with Heather in that I have not seen anyone promoting high growth rate as a sign of good husbandry, or tortoise health in general.

You will see it if you read a cross-section of various journals. It crops up quite frequently. In the Israeli study cited above, for example, the idea was to use high growth rates to "farm" Testudo... this is not an isolated case. In fact the same authors wrote another paper suggesting the same thing. It is a concept you see put forward quite often.

How would I as a keeper of a single sulcata measure bone mineral density? Is this something that my local reptile Vet could do for me, and how often should it be done?

Honestly, you should not need to, certainly not on a routine basis. This is not something every keeper has to do. Once a good basic diet, and suitable environment is adopted, very few problems will occur. Major problems only tend to be seen where husbandry is quite evidently defective.

If you adopt a diet (for a herbivorous tortoise) that offers:

a) High fiber (aim for >30%)
b) High calcium, low phosphorus (>5:1 minimum, preferably >8:1)
b) Wet basis protein levels in the 4-5% range (DM circa 9%)
c) Avoids highly fermentable carbohydrates/starches

and

d) Provide adequate UVB
e) A suitable thermal environment
f) Adequate space and exercise and avoid overfeeding

.... you will, generally, be absolutely fine.

 

[Testudoresearch]

Dealing with a problem by alleviating its symptoms does not mean you have solved the problem; but you have put "sticking plaster over the wound"

Precisely.

Let me try to be really clear here.

You can prevent/suppress 'pyramiding' by maintaining the scute keratin at saturation point, almost regardless of nutritional factors. The physics are really simple. Soft keratin results in a massively reduced stress loading on the skeleton. However.... as I said in the first edition of the "Tortoise & Turtle Feeding Manual (2000), when these methods began to be suggested:

"It is also vital to note that none of the other consequences for health.... would in any way be ameliorated by increasing ambient humidity during such growth even though the most visible external effect known as ‘pyramiding’ may be reduced"

That was written well before the complete mechanism had been fully explored and explained (as set out in our initial presentation in 2010).

The full paper appears as a chapter in the new edition of that text which is appearing shortly.

In short, 'Pyramiding' is a SYMPTOM of a problem, not the problem itself, and the symptom can be suppressed using extreme husbandry techniques (saturation at high temperatures), because this changes the physical property of the keratin (temporarily). Remove the humidity/heat and normal stiffness will return.... better hope all the bones are very good condition at that point....

When the extreme humidity is removed, the keratin will begin to equalize to normal ambient humidity. It will stiffen and shrink... considerable pressures and stresses will be generated. Not theory. Proven material science. Look it up.

 

[Tom]

And I hardly think that anyone is promoting "intentionally growing them slower by starving them, dehydrating them, and keeping them cold and dark throughout the year", either. That is an insulting insinuation.

Insulting insinuation? This is exactly what Andy has suggested for people to do. He says to not feed them three times a week, leave the heat and lights off sometimes, and posted pics saying that he doesn't even see some of his tortoises for months at a time. I cannot sit by and pretend any of that is okay or acceptable. It isn't to me. I feel sorry for his tortoises.

Now there is a certain logic to this. Dealing with a problem by alleviating its symptoms does not mean you have solved the problem; but you have put "sticking plaster over the wound" and it's often the best we can do. I think Tom is acknowledging this, and he is presenting us with what he has found to be good "sticking plaster" for certain problems with growing Sulcatas....

I will agree with this to a point. But I don't find 80% humidity, 80 degree temps, and daily soaks, to be "sticking plaster over a wound" for sulcatas. They do experience these conditions in the wild for at least part of the year from everything I have been told and read, and in this case, it DOES seem that I have solved the problem. Further, these things work in actual practice, where all else has failed. Turns out that these things also work very well for starting hatchlings of many other species whether or not those species experience those conditions with regularity in the wild.

The honest truth is that there is no way that we can ever completely remove the problems inherent in keeping a species in an environment it has not evolved to live in. The animal is "not meant to live here".
We can only (a) decide that it is wrong to keep an animal outside of its natural habitat (which is a perfectly reasonable conclusion) or (b) work towards finding the best alternative environment that the animal can cope with, and which is within the owner's capabilities and resources.

This seems to me to be a very insightful way of looking at all this. I frequently consider point (a) when I hear people lamenting about their lack of funds or space. Option (b) is what I have spent more than 2 decades trying to perfect. I have spent untold thousands of dollars and I can't even count the number of thousands of hours trying to determine what is "best" in a PRACTICAL sense. This is why when Andy's second post on this forum specifically addresses me, by name, and then decries what I have learned as "unnatural", "insane", or somehow detrimental, I react with defense of my stance.

I have raised dozens of animals using the techniques he describes and recommends. The results for me, and for hundreds of others that I have observed, were not satisfactory for sulcatas or leopards. In my experience, his recommendations will work fine for Greeks, Russians and CA desert tortoises. By contrast, Andy has never raised a single animal using the techniques that I recommend. Nor has he seen first hand or examined a single one. Yet he accuses ME of making statements and assertions that are made up and don't have proper scientific data to back them up.

I think Testudoresearch is right that there are going to be long-term health issues which are not at all obvious in the first decades, maybe the first half-century of life, when animals are taken out of the environment they evolved to inhabit, and so many factors are altered.

This I do not understand. Please elaborate. So you are saying that with good temperatures, diet, hydration, and outdoor exercise and sunshine, my tortoises are going to grow up and seem to be healthy and fine, but somehow, after 50 years of health and reproduction, I am going to discover some health issue because of how they were started 50 years ago? Forgive me, but this defies any known logic, and I can think of nothing to relate this too. Unfortunately, it is likely that none of us will be around to see if this is true or not.

Free unlimited access to food throughout early life is inevitably going to increase growth rates over those which a perfectly healthy youngster in its own habitat, in the best of years, would achieve, even without parasites, predators etc. It is a technique used in "headstarting" re-population programs worldwide, for rearing baby reptiles of highly endangered species so that they will be big enough to have a better chance of survival than wild babies would have done, at the time of release.

Here you bring up a good point. This "head-starting" and faster than wild growth rates, may indeed present a problem for SOME tortoises in SOME situations. Case in point: At this years TTPG conference we received several presentations on the goings on in the Galapagos. Don't remember which Island offhand, but it is one of the very sparsely vegetated ones. For 70 years there has been NO wild reproduction because introduced rats consume hatchlings upon emergence. (This problem, thank goodness, has now been solved and wild reproduction has resumed after all these years...) The researchers have been collecting eggs and head starting the babies for decades before reintroducing the tortoises to their island of origin once they get to a size where the rats wouldn't bother them. After nearly 20 years these head-started babies are literally twice the size of their wild raised parents. Normal adult size for this island is around 90 pounds, while some of the tortoises that were head started for 5 years and then released back onto the island have now attained sizes of 180 pounds. Interesting to me that those first five years has such a profound effect, even after the next 15 years is spent with the islands limited hydration and nutrition issues. They are concerned that these giants may have trouble surviving down the road because the island might not be able to support the caloric needs of such large animals. It is a study in progress.

This highlights the profound effect that we humans have over these animals lives based on what we do or don't do. Since none of our animals are intended for wild re-release, it seems logical to me to try and give them the best we can. As has been noted, I am not trying to grow my animals at any speed, fast or slow. I am trying to grow them healthy. If they are larger than their wild counterparts of the same age, I am okay with that and can see the reasons for that.

lilacdragon, I don't know who or where you are, or what your background is, but you demonstrate an insight and open-mindedness that many don't. I appreciate that, and look forward to more.

---

When the extreme humidity is removed, the keratin will begin to equalize to normal ambient humidity. It will stiffen and shrink... considerable pressures and stresses will be generated. Not theory. Proven material science. Look it up.

You are dead on here, and this is my current issue. I start hatchlings with the methods you decry as so extreme, despite the obvious success of the techniques, but at some point these babies grow up and have to live outside in my dry climate. I gradually have the babies spend more and more time outside on a daily basis as they gain size. A weaning, of sorts, from the conditions that allowed their carapaces to form naturally as tiny hatchlings. Once they are outside full time, the scute margins begin to reflect the dry growing conditions.

For this problem, I have not yet found a satisfactory solution. Any suggestions?

 

[Testudoresearch]

There is some stuff on this forum that is so good I just had to grab a screenshot of it. No-one would ever believe it otherwise



On the subject of Agrobs vs. Zoomed and Mazuri and similar highly processed products, I realized I had done a "condensed" little write up on that which is from the "Tortoise Trust Guide to Tortoises & Turtles" (4th edition) combined with some text from the new version of the "Feeding Manual". Might be helpful to quote it in full because it explains why chopped fibers are problematic:



Provision of adequate herbivorous tortoise diets can be challenging, requiring the sourcing of a wide range of plant materials (which may suffer seasonal lack of availability) and additional supplements. Many keepers and program managers therefore seek a more convenient way of providing a satisfactory diet for their animals. A number of manufacturers have tried to address this market with pre-packaged pelleted foods. Many of these are described as “complete diets”. Stated analysis of such foods indicates that with few exceptions the crude fibre content is typically substantially less than 20% and in some cases is below 12%. Most manufacturers also label their products to indicate the maximum fibre content, and fail to divulge either the average level or the minimum level, which can prove very misleading. Studies by Hatt, Clauss, et. al. (2005) suggest that if high rates of digestibility in tortoises are to be avoided, the crude fibre content on a DM basis needs to be in the order of 30 to 40%. As we noted in the example of grinding dry vegetable matter, the crude fibre content remains the same, but digestibility varies enormously according to the size of the resulting particles and also according to how much damage has been done to the protective cuticle surrounding the plant cells. For ease of extrusion, commercial manufacturers typically utilise fine particles and softer grade fibres. Donoghue and Langenberg (op. cit.) also point out that process used in extrusion and pelleting involve high temperatures that partially destroy labile vitamins. Such processes typically also degrade the protective integrity of the plant cells by damaging the waxy cuticle. It has already been noted (above) that the more a whole plant part is chopped, ground, degraded or processed the greater the number of cells that will be immediately exposed to immediate microbial attack. There is, therefore, a major difference in derived energy between a tortoise consuming nearly-whole plant parts and a tortoise consuming highly processed plant parts with very much more surface area available to the gut microflora.

While it is the case that on the surface pelleted foods may appear to be an attractive means of providing dried vegetation to captive tortoises, most - as noted - fail in a number of critical respects. The development of pelleted foods that include a high proportion of very long fibres, coarse, large particles and an appropriate protein and trace-element content should not be impossible, however. Some commercial manufacturers have already moved in that direction (Pro-Alpin and Pre-Alpin Testudo). These products are unusual in that they include a much broader diversity of plant species than typical mass-produced pellet feeds, and they omit the potentially very damaging grain and maize-based derivatives included in most other commercial offerings. They also have crude fibre and protein levels that more closely approximate that of the typical wild diet. Other manufacturers and some independent smaller scale specialist suppliers are also offering a range of dried edible herbs and “weeds” (JR Farm). Over the last few years a new mini-industry in supplying seeds, and both fresh and dry food plants to tortoise keepers has appeared, with many independent sellers of such items on sites such as Ebay. One common problem area with many of these independent suppliers, however, is the lack of adequate quality control and accurate labelling. Such products will, hopefully, continue to develop. There is room for such products, and certainly room for further developments in this field. The use of compression of a kind that results in minimal plant cell damage rather than extrusion to produce pre-packaged foods, the avoidance of high temperatures in the production process, and the inclusion of plants grown in the Mediterranean zone are some areas that should be considered.

These products are certainly a very useful addition to the options available to today's keeper and breeder who is concerned with achieving high quality, healthy growth. The best way in which these products (and others like them) can be most effectively utilised is still very much in the early stages, however. Good results are already being reported using a combination of these dried sources (e.g. the Alpin Testudo) range in combination with a well-designed, well-balanced and healthy diet of fresh plants, combined with additional calcium supplementation and adequate UV-B lighting and provision of suitable basking temperatures. More work needs to be done on establishing the ideal blend between provision of dried plant material and fresh plant material to produce consistently healthy growth, however. It is clear that in addition to controlling the gross protein level of captive tortoise diets, and ensuring adequate levels of calcium, vitamin D3 and other bone-building essentials, the control of fibre intake and digestibility is equally important.

It is only 20 or so years ago that many organisations and veterinarians advising on tortoise husbandry were still recommending a diet of lettuce, tomato, dog food and boiled eggs for captive tortoises, and the need for UVB was almost entirely ignored - so we have come a long way. We will only make further progress based upon a foundation of reliable observations of tortoises in the field, encompassing both behaviour and feeding patterns, accurate analyses of key dietary constituents, and a more complete understanding of their complex and highly variable temperature dependent digestive and vitamin D3 metabolisms."

 

[lilacdragon]

Hi, guys.

To whom it may concern: Will you two alpha males please stop sparring with each other about which of you is the most insane/unbelievable/cruel tortoise-torturer in the world? I suspect that you both care deeply about your animals and have a great deal of valuable knowledge that you could share with each other. But every time I read your posts, I have an image of two huge beautiful 6ft male Green Iguanas standing broadside on to each other, dewlaps flared, eyeing each other for possible weaknesses and preparing for a crushing tail-whip. It is very distracting

This I do not understand. Please elaborate. So you are saying that with good temperatures, diet, hydration, and outdoor exercise and sunshine, my tortoises are going to grow up and seem to be healthy and fine, but somehow, after 50 years of health and reproduction, I am going to discover some health issue because of how they were started 50 years ago? Forgive me, but this defies any known logic, and I can think of nothing to relate this too. Unfortunately, it is likely that none of us will be around to see if this is true or not.

Tom, I will need to collect some references for my reply to this very good request. Please bear with me as I collect up what I need. As regards tortoises specifically, I don't have much data. I hope Andy will be able to indicate some good quality research we can read.
But as a veterinarian (although now retired) I have always been very aware that much anatomy and physiology applies to all vertebrate life, so it is often perfectly okay to cautiously extrapolate when dealing with very basic principles...
There is a growing field of human data on the effects of what seem like minor, inconsequential deficiencies early in life, to adult health. There are also disturbing associations between certain apparently harmless things, like diet and light-at-night, and later development of cancer, in mammals. I'll dig out the papers and post some links to them.

And there are some absolutely amazing peer-reviewed papers on reptilian physiological responses to - for example - changing daylength, seasons, temperatures... So I have many un-answered questions about how years of not-quite-normal responses will affect the health of our animals.

For example: Reproduction is well known to be controlled, in many reptiles, by the presence of a period of good nutrition (eg. good plant growth the preceding spring) followed by a cold period with little or no food. What if the ovaries receive the first part of the stimulus but not the second? What if ovulation in that species is not spontaneous, but requires the stimulus of mating? .... is it possible that eventually these ovaries will develop harmful cystic changes, follicular necrosis, ovarian cancer? Will the annual resorption of mature follicles with their high fat content cause gradual liver damage?

These are the questions I have. My actual experience is very limited indeed but over the last 20 years I have lost several adult female lizards of three very different species, apparently very healthy and well cared-for, but not bred from, with ovarian problems undiagnosed until post-mortem. And the only leopard gecko I have ever post-mortemed which did not have an unhealthy-looking fatty liver was a skinny little thing that had some sort of lizard equivalent of irritable bowel syndrome, that we never found the reason for. She never got that "healthy plump" look that everyone likes to see. But when she died, on post-mortem she had the healthiest, most beautiful liver, I realised I'd never seen a normal one before.

Best wishes
Frances

 

[Testudoresearch]

Certain parallels stand out for me from simply being involved in this for a very long time. I remember when "cat, dog and monkey chow" diets were being heavily recommended. Your tortoises grew twice as fast! You can breed them in half the time! It actually took well over 15 years before people started to wake up to what else was happening. Fatty degeneration of the liver... gout... kidney disease... MBD....unfortunately, as someone once said to me (and it stuck in my mind) "tortoises die slowly"....

The "pellet foods" were another disaster area. Again, sold to keepers as "scientifically formulated"! Some were (and still are) supposed to suit everything from a box turtle to a redfoot to a sulcata and a Russian in between..... we saw protein (DM) levels of 22%. Calcium to Phosphorus ratios of less than 2:1, poor fiber content, all kinds of additives - some of them rather strange, and which no-one had any clue as to what they might actually do in real life with a reptile. Independent tests found that some products did not even match what was on the 'contents' label. Thousands of keepers used these products, believing what was claimed. It became obvious there were huge problems - too late for some, sadly. That also took 10 years+. Even now, many products fall far short of the marketing hype.

As with environment (including UVB), if we take our cues from nature, we are on reasonably safe ground. The further we depart from that, the further we head into unknown territory - and any "mistakes" could take years to become evident.

 

[ulkal]

Hi, guys.

To whom it may concern: Will you two alpha males please stop sparring with each other about which of you is the most insane/unbelievable/cruel tortoise-torturer in the world? I suspect that you both care deeply about your animals and have a great deal of valuable knowledge that you could share with each other. But every time I read your posts, I have an image of two huge beautiful 6ft male Green Iguanas standing broadside on to each other, dewlaps flared, eyeing each other for possible weaknesses and preparing for a crushing tail-whip. It is very distracting

100% agree. Let alone how much others can learn from a civilised ping-pong between knowledgable people who do not agree on certain things

 

[Sulcata_Sandy]

I radiographed my 20 year old WC RF today.

Guess I better call the person I got her from and ask if she's been exposed to males. [GRINNING FACE WITH SMILING EYES]

She is 11.5" and 8 lbs. I caught her nesting yesterday. Thoughts on her bone density?
I will get my CB male imaged soon.

Apparently I popped in just in the middle of a heated diet debate. LOL

Andy? Any thoughts on this radiograph? I will image the CB male next week, prob Tuesday.

---

 

[Testudoresearch]

Did reply in post 142, Sandy:

"Difficult to get a totally accurate analysis with that image size/resolution, but the pelvic and limb bones appear well formed and of acceptable density. The carapace mineralization appears (to me) to be possibly a little bit on the 'light' side. It is not gross, however and may not be significant. I would not like to reach a firm conclusion from that one image. There is nothing there that I can see that suggests anything seriously wrong. The eggs appear well-calcified"

Keratin....

If you wish to read some really detailed, well-referenced material on what happens to keratin at various levels of humidity, there is one paper I can highly recommend. You can access it in full for free, here.

They used horse-hoof keratin for this paper, but tortoise carapace (and beak/nail) keratin behaves in a very similar manner. The mathematics are at times quite challenging, but quite a number of things jump right out. It is worth a read as it really does show exactly what is going on when you place a tortoise in a hot, very high humidity environment. The table of references contains a number of other important papers on this topic, many of which are also relevant to chelonian carapace keratins and their responses to differing levels of hydration status.

 

[Sulcata_Sandy]

Did reply in post 142, Sandy:

"Difficult to get a totally accurate analysis with that image size/resolution, but the pelvic and limb bones appear well formed and of acceptable density. The carapace mineralization appears (to me) to be possibly a little bit on the 'light' side. It is not gross, however and may not be significant. I would not like to reach a firm conclusion from that one image. There is nothing there that I can see that suggests anything seriously wrong. The eggs appear well-calcified"

Keratin....

If you wish to read some really detailed, well-referenced material on what happens to keratin at various levels of humidity, there is one paper I can highly recommend. You can access it in full for free, here.

They used horse-hoof keratin for this paper, but tortoise carapace (and beak/nail) keratin behaves in a very similar manner. The mathematics are at times quite challenging, but quite a number of things jump right out. It is worth a read as it really does show exactly what is going on when you place a tortoise in a hot, very high humidity environment. The table of references contains a number of other important papers on this topic, many of which are also relevant to chelonian carapace keratins and their responses to differing levels of hydration status.

Oh, thank you, Andy, I did indeed miss your reply. And I agree, tough tough to evaluate fully with this small res image, just wanted a quick peek and initial thoughts. Very appreciated. I will image my CB male this week. Would you be interested in me mailing those to you? I have to way to make a true digital image, unless I call around for having the images scanned. We still have old equipment.

And thank you for posting the link to the equine keratin paper, I am erasing that now.

 

[paludarium]

Analysis of fecal pellets is a useful tool. You can see here just how incredibly fibrous it really is....compare with output from most captive 'pet' examples. There is an enormous difference.

One very interesting fact is that very, very little (if any) weight loss occurs during either brumation or estivation. You might expect tortoises to be dehydrated after, say, three months underground with surface temperatures just a few inches above them like this...

51.2 Celsius or 124.16F.

But... they are not in the least. They remain very well hydrated and losses are near imperceptible. A testament to their excellent 'design' and total suitability to be right 'at home' in this kind of environment.

Field researches provided us important information and facts, but due to interoberver and intraoberver variations, those facts were not always truths.

Wegehaupt's website http://www.testudo-farm.de/html/habitatsklima.html also recorded some informations about the climate in a habitat of European tortoises. Please take a look at picture at the bottom of the page, the shoes were extremely WET in the early morning, the author also wrote that "der Boden einschliesslich der bodennahe Bewuchs und somit auch die darin lebenden Schildkröten sind zumindest in den frühen Morgenstunden extrem feucht. "(sorry, in German).

The fecal analysis, too. A few analyses of stool samples from some individuals showed only what some tortoises might have eaten a few weeks ago. Those stools did not represent their real diets. However, if the data were collected from hundreds of tortoises over a period of 10 years, the information would be more objective. According to a research in Romania, Long term observations on the alimentation of wild Eastern Greek Tortoises Testudo graeca ibera (Reptilia: Testudines: Testudinidae) in Dobrogea, Romania. occasional intake of animal food, i.e. carrion, was also noticed. Tortoises were observed feeding on a dead wild cat, as well as on remains of dead birds, bovines and ovines, leftovers from the prey of jackals and/or feral dogs. Overall, the carrion (and generally animal food) intake seems far less marked than in other studies, but the authors cannot exclude that this could be due to a method bias since through direct observation it is more difficult to find animals feeding upon carrion.

Stool analysis has another limit. The foods with more fibers that are hard to digest will be more easily detected in the stools. Therefore the actual percentage of the easily digestible parts like animal matters would have been underestimated. We probably have to analyse the stable isotopes of carbon and nitrogen in the carapace scutes, like the study Asynchrony between dietary and nutritional shifts during the ontogeny of green turtles (Chelonia mydas) in the Mediterranean.

I don't think the pathophysiologic processes of pyramiding are now well known, the information extrapolated from the studies for other species especially from mammals, are misleading and not reliable. I won't do that.

Erich

 

[Testudoresearch]

Wegehaupt's website http://www.testudo-farm.de/html/habitatsklima.html also recorded some informations about the climate in a habitat of European tortoises. Please take a look at picture at the bottom of the page, the shoes were extremely WET in the early morning, the author also wrote that "der Boden einschliesslich der bodennahe Bewuchs und somit auch die darin lebenden Schildkröten sind zumindest in den frühen Morgenstunden extrem feucht. "(sorry, in German).

Yes. You get dew in the morning in some localities at some times of year. You get more of it in the coastal zone than you do further inland, typically. This proves what, precisely? It is well known. It also burns off very quickly as the sun rises. You also get it in true deserts under some climatic conditions. Everyone knows this... It is the dew point.

The fecal analysis, too. A few analyses of stool samples from some individuals showed only what some tortoises might have eaten a few weeks ago. Those stools did not represent their real diets.

??????????

If that is what you believe then you need to tell all the biologists who have been relying on this data for decades.

However, if the data were collected from hundreds of tortoises over a period of 10 years, the information would be more objective. According to a research in Romania, Long term observations on the alimentation of wild Eastern Greek Tortoises Testudo graeca ibera (Reptilia: Testudines: Testudinidae) in Dobrogea, Romania. occasional intake of animal food, i.e. carrion, was also noticed. Tortoises were observed feeding on a dead wild cat, as well as on remains of dead birds, bovines and ovines, leftovers from the prey of jackals and/or feral dogs. Overall, the carrion (and generally animal food) intake seems far less marked than in other studies, but the authors cannot exclude that this could be due to a method bias since through direct observation it is more difficult to find animals feeding upon carrion.

Again... this has already been discussed. Such intake is extremely limited. I have personally examined hundreds of samples over many years. I continue to do so. As already stated, if they find something, they are opportunistic and will eat it. However, there are far more efficient (and dangerous) scavengers around who get this stuff first... and if a tortoise is there, would could take that too. I have found occasional evidence... snake skin... lizard skin... beetle...this has been really quite rare and is absolutely no way a significant proportion of their normal diet.

Stool analysis has another limit. The foods with more fibers that are hard to digest will be more easily detected in the stools. Therefore the actual percentage of the easily digestible parts like animal matters would have been underestimated.

I don't think so.

I don't think the pathophysiologic processes of pyramiding are now well known, the information extrapolated from the studies for other species especially from mammals, are misleading and not reliable.
Erich

Explain - precisely - how you think it is "misleading". Are you, for example, claiming that chelonian keratin has completely different physical properties from other keratins? That is is not hygroscopic, for example? Or are you claiming that the bone metabolism of chelonians is unique and operates on different principles entirely from all other known animals?

Please. Tell me.

 

[Yellow Turtle]

For 11 pages, this looks like very hot debates.

While I accept all the theories from Andy about pyramiding, keratin, humidity, diet, etc. I can't help but wonder, is Tom's way of raising hatchlings inside humid environment brings harm effect to those hatchlings? Instead of this prolong debates, isn't advanced medical technique now enable us to monitor those hatchlings health easily? Blood samples, bone densities, internal organ imaging, aren't they sufficient enough to at least indicate if anything goes wrong with those hatchling?

Time will eventually tells what happens to those hatchlings in the future, but at least for now, I would just enjoy raising my torts and see what current technology says about those hatchlings' condition raised inside closed chambers. Since Andy and Tom are the 2 alpha males here, why don't you guys just make a bet and do those medical analysis on those torts. Losers pay for all medical fees...

Btw, Tom, can you show us all the new pictures of the earliest torts raised inside those closed chamber? I just wonder how big they are now and current condition of the scutes. I believe they are raised fully outside now, and I'd like to know whether they can maintain those perfect smooth scutes till now.

 

[Yvonne G]

I was thinking about this too. I know you're busy, Tom, but could you take some time to add some current pictures in the same thread where you show the pictures of the babies in their closed chambers. You did keep some of them, right?

 

[Testudoresearch]

There some photos on paludarian.net of T. horsfieldii that are very strange and rather worrying.

As for tests, we are happy to fund some tests, provided they are properly documented and carried out by qualified veterinarians. Another thing that would be very useful is analysis of skeletal material from deceased tortoises that could then be directly compared to identical material from healthy wild examples. We do not support and never fund any form of research that involves killing ('sacrificing' ) animals, so such would have to originate from animals that have died naturally from other causes.

---

I'd also like to address one more area of the bizarre and wacky pseudo-science that has infected this whole issue and which so far, has only been mentioned briefly. This is the question of alleged "dehydration".

It is important to note right at the outset that semi-arid habitat tortoises are effectively "built" to make very efficient use of available water, and their metabolism functions in a manner that requires minimal inputs. Their excretion of urates is the best example. Their structure too, is intended to guard against fluid losses in very low humidity environments. Overlapping, heavy limb scales, for example as seen in G. sulcata, G. pardalis and T. kleinmanni. Smaller ocular orbits - compare an equivalent-sized G. pardalis to a G. denticulata or K. homeana, for example...all of these features help to prevent fluid loss. All of this is basic level comparative Eco-physiology.

So... alleged dehydration....

We have heard the term "cellular dehydration" used. The “cellular dehydration” suggested here would seem to be impervious to improvement when the animal drinks. Fresh water was freely available for all of the groups of Geochelone sulcata in Weisner and Iben’s experiment, for example. An animal that is dehydrating to the point where cells are “collapsed” would surely be motivated to drink. This would rapidly reverse any such dehydration. Other keepers have noted the same anomaly: “it appears to involve a dehydration of the animals that, for currently unknown reasons, is not compensated by the oral intake of water” (Kruger, 2008). The entire concept that the animal can be drinking, feeding, growing, have normal urinary output, and apparently in every other sense remain metabolically healthy while suffering from some form of medically unrecognised condition of “cellular dehydration” of the collagenous tissues is simply not credible when viewed from the perspective of established veterinary and physiological science. In accepted veterinary and medical literature, the term “cellular dehydration” is not used to describe a condition distinct from chronic dehydration, but rather to point out the effects of generalised dehydration on living cells. Therefore, an organism not suffering from dehydration is in no danger of suffering from cellular dehydration.

A very similar theory was advanced by Bidmon and Jennemann (2006) , who also believed that low environmental humidity was the sole cause of the “pyramiding” effect. Again there is the suggestion that lack of a high humidity microclimate surrounding the tortoise causes some form of internal dehydration and “lack of pressure” in the cells of the connective tissue. These authors suggest that the site of this “dehydration” is primarily via the clefts along the new growth ‘rings’. This theory fails for the same reasons cited above, and completely ignores the fact that this area of new growth is well supplied by a rich flow of blood (and consequently is invariably well hydrated) via layers of epithelial cells and connective tissue rich in nerve endings (Haycroft, 1890, Albardi 2005).

Semi-arid habitat tortoises do not need to be kept in "damp" or "wet" environments to avoid dehydration. This totally ignores their entire evolutionary physiology. They are adept at maintaining adequate hydration in some very seriously difficult environments. They do this through a combination of their specialized physiology, and also though behavioral means. These suggestions to the contrary by amateur keepers quite simply defy logic and defy established science. It is pseudo-science.

I have asked several people who believe in this stuff to explain to me how the processes that they are referring to can possibly occur. No-one ever has. Quite simply, how could an otherwise healthy tortoise, that has free access to drinking water, become so dehydrated that its cells would "collapse", especially in moderate levels of humidity in the 45-60% range?


Alibardi, L. (2005). Proliferation in the Epidermis of Chelonians and Growth of the Horny Scutes J. Morph. 265: 52-69

Bidmon H.J. & Jennemann G. (2006): Hohe relative Luftfeuchtigkeit - gleich glatte Panzer: Wie lässt sich das in der Landschildkrötenhaltung praktikabel realisieren? - Schildkröten im Fokus, 3(4), Bergheim

Haycroft, J. B. (1890) Termination of Nerves in the Nuclei of the Epithelial cells of Tortoise Shell. J. Microscopical Science. (2-31): 124 pp 563-570.

Kruger, E. (2008) Moist Root Shelters for Hatchlings. Radiata 17 (2), 14-18

 

[Yellow Turtle]

Well Andy, if you can fund such tests, I really hope for the sake of hobbyist here, you and Tom can work together for that.

There is really no point, amidst so many theories that contradict each others, to further debate this. A series of lab test would provide all the answers to us.

Also I point out a question last time, for environment like in my area, with 2 seasons, humidity 30-80% depends on season, and greens grow all years. No chance for hibernation nor estivation. So from the whole theories I've been reading, this should not be the suitable environment to raise any desert tortoise. So instead I should raise them indoor only and also provide artificial hibernation?

 

[Testudoresearch]

There is really no point, amidst so many theories that contradict each others, to further debate this. A series of lab test would provide all the answers to us.

There are two common definitions of what constitutes a "theory":

1. . A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.

2. An assumption based on limited information or knowledge; a conjecture.

Both are present in this discussion....

Also I point out a question last time, for environment like in my area, with 2 seasons, humidity 30-80% depends on season, and greens grow all years. No chance for hibernation nor estivation. So from the whole theories I've been reading, this should not be the suitable environment to raise any desert tortoise. So instead I should raise them indoor only and also provide artificial hibernation?

I would concentrate on keeping species that better suit your environment. I would not try to keep tropical turtles where I live (in a semi-arid habitat bordering a true desert). You will always be fighting the environment... not working with it. That is just my personal view...

It can be easier to create a humid area in a dry environment than the other way around, too....that can be very difficult. The only species I now keep are those that occur within the same bioclimatic zone that I actually live in. I used to keep many different species, but now, concentrate on just those that are best suited to the climate where I am located.

 

[Yvonne G]

I'm not a scientist, and I don't have a scientific mind, however, I can tell when a baby box turtle is so dehydrated that he might die soon. I have a brand new baby box turtle living in a well-planted plastic tub and there is a waterer in the habitat. The soil is kept moist because of the plants. But because the waterer is shallow so the baby doesn't drown, it evaporates before the day is out. I re-fill it every morning. If I have forgotten to re-fill the waterer, the baby is obviously dehydrated, with sunken eyes and is very light weight.

I also raise baby tortoises. This same dehydration factoid is common with them too. If I don't soak the babies every day, their eyes sink in and they are very light when you pick them up. I don't know if they are retaining their urine, and I don't wait to find out. I soak them to be sure they don't become so desiccated that they die.

In order to have the high temperatures in our indoor habitats to keep the babies alive, we have them on "slow cook." It makes good sense to soak babies every day.

So, you say, don't have the temperature so high. If you keep a baby too cool you run the risk of having it get sick. We do what we have to do.

 

[Testudoresearch]

I'm not a scientist, and I don't have a scientific mind, however, I can tell when a baby box turtle is so dehydrated that he might die soon. I have a brand new baby box turtle living in a well-planted plastic tub and there is a waterer in the habitat. The soil is kept moist because of the plants. But because the waterer is shallow so the baby doesn't drown, it evaporates before the day is out. I re-fill it every morning. If I have forgotten to re-fill the waterer, the baby is obviously dehydrated, with sunken eyes and is very light weight.

I also raise baby tortoises. This same dehydration factoid is common with them too. If I don't soak the babies every day, their eyes sink in and they are very light when you pick them up. I don't know if they are retaining their urine, and I don't wait to find out. I soak them to be sure they don't become so desiccated that they die.

What heating and lighting are you using with tortoises? What species are they? Ambient humidity in room?

That sounds to me to be a very extreme and rapid level of dehydration. If eyes are sinking that fast, something is very wrong. I have raised many species of terrestrial tortoise (around 25, as I recall) and while I totally agree with you that care must be taken over hydration levels, if I was seeing tortoises dehydrate to the point of sunken eyes in under 24 hours - I would be very concerned indeed. Eve when rearing quite large numbers in very artificial conditions, I never saw anything as severe as that.

Obviously, North American box turtles are not (apart from T. o. luteola) found in particularly arid habitats and they lack the protections that true arid habitat species possess that dramatically reduce fluid losses. As already mentioned, Hingeback tortoises are similar to box turtles in that regard. T. o. luteola is unusual in that peak activity occurs around 60% RH, and they become largely inactive at circa 39% RH. With T. carolina I did keep these for many years, and agree that a relatively moist environment is required, especially for juveniles.