| Kirkie |
24-01-2009 03:21 PM |
Hi Anna, You might need PDF reader to view it but heres the pertinant part:
When raising juveniles of certain tortoise species, one sometimes unfortunately observes the development of deformations of the bony shell, especially in the region of the back.Discussions about potential causes of this so-called “pyramiding” commonly revolvearound factors such as unnaturally acceleratedgrowth due to a diet that is excessive in both quantity and protein (Highfield 2008 ), Insufficient intake of calcium (Frye 1991,Gerlach 2006), or excessive intake of calcium (Stancel et al. 1998 ). In recent years, a latent dehydration has also been implicated (Wiesner & Iben 2003). It is possible that the formation of a humped shell results from a combination of the above-mentioned factors, since it appears to involve a dehydration of the animals that, for currently unknown reasons, is not compensated by the oral intake of water (pers. obs.).
To remedy this problem, some breeders recommend that juveniles be bathed on a regular basis, as this enables them to absorb additional moisture via the skin (Harless & Morlock 1989). Most keepers have furthermore changed to housing their Testudo juveniles in a relatively moist environment,especially at night. This measure may appearto be counter-intuitive at first, since one would expect the natural habitats ofthese animals to be for the most part very dry. However, the reasons why hatchlings in the wild do not experience a comparable dehydration presumably lies, next to their naturally slower growth rate, in their much more covert lifestyle. During their first few years of life, juvenile Testudo spend almost their entire time under the thick undergrowth of the Mediterranean maquis and garrigue.
In periods of inactivity, they frequently bury themselves in the ground, typically in the fully shaded root areas of bushes and shrubs. Here, evaporation from the vegetation creates a higher level of relative humidity than an overall impression of the landscape suggests and the climatological charts indicate, the latter data usually being gathered at a point two meters above the ground. Moreover, even when the plants and soil are completely dehydrated, they still reduce the air volume surrounding the small animals and thus decrease the loss of fluids through evaporation, much in the same manner as dry cling wrap counteracts the dehydration of groceries. In contrast, juvenile Testudo in human care soon lose their initial shyness towards their keepers and potential predators and as a consequence retreat into their shelters less frequently. Furthermore, our lower air temperatures necessitate longer and more dehydrating basking sessions, since the ambient temperature almost always ranges below the preferred body temperature of these animals. In my experience, this increased dehydration can be more effectively compensated by providing soil- or root-based dens at night (Fig. 4) than by raising the level of humidity in solid shelter huts. The larger air volume in these huts caused my juveniles to dehydrate more even at increased humidity levels than if their shell was in close contact with a moist substrate. My initial concern that spending the night in a damp environment might lead to respiratory tract infections or cause skin or shell diseases proved unfounded in the Testudo graeca soussensis in my care, even though this species is considered to be sensitive towards moisture. Nevertheless, it will be left to every tortoise keeper to take into consideration the specific needs of the species and individuals in his or her care.
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