tartarugas terrestres e piramidismo

[pika_sp]

como tenho uma tartaruga leopardo africana e agora deu um pulo de crescimento, estou preocupado com o piramidismo.
já li muita coisa.. como sendo a causa de.. (dieta, temperatura, exercício, UV.....)

e do que que li concluí que:
- tudo são factores condicionantes.
- dieta incorrecta, temperatura, etc produzem um certo grau de piramidismo quando favorecem um rápido crescimento (mas ñ é a causa de piramidismo grave).
- o factor mais importante é a humidade pois na natureza tb ocorre o piramiismol, em climas/anos/temporadas mais secos(as).
- as tartarugas que se escondem em tocas no subsolo (com mais humidade ambiental) e com agua para banhos regulares apresentam menos piramidismo.

deixo um dos textos que recolhi na net.
agradecia comentarios e criticas "as minhas" conclusoes.
obrigado


The most recent research has dispelled all the guesses about pyramidding being the result of overfeeding, too much protein, not enough calcium or UVB, and other assumptions. As a matter of fact, just about everything but the quality of air that they breather has been attributed as the cause. After extensive study with Sulcatas under different conditions it was found that the overwhelmingly main reason for pyramidding came down to the humidity conditions, epecially in the first 2 years. High protein, calcium & vitamin supplement intake, etc. merely resulted in greater growth rates. It should be noted that pyramidding commonly occurs in nature as well due to the natural conditions at the time and is not in any way exclusive of captivity. The permanent pyramidding occurs in tortoises under 2 yrs and if they have made it to that point without pyramidding, it appears from research that they never will develop it, regarless of the conditions. If they have acquired pyramidding by that young age, then the degree to which it is displayed is all that can be controlled after that point on, but a tortoise with pyramidding from it’s younger years really has no effect on it’s current health or a later age if it’s cared for correctly. Even if it’s fed high protein, low calcium diets.

Research finds that hydration is crucial to preventing pyramiding


SUMMARY: Researchers using Geochelone sulcata hatchlings with controlled humidity settings and controlled dietary protein levels found that providing adequate hydration was much more crucial in preventing pyramiding than reducing dietary protein.

Regarding our emailings on this list, we’ve had several requests for reprinting in hard copy and also for forwarding to other lists. Both are fine and permitted as long as credit is given to our HerpNutrition list and Walkabout Farm. Our goal is simply the dissemination of knowledge in order to advance the science of herpetoculture, so it’s great to see the information out there in other venues.

Those of you with tortoises and turtles are perhaps familiar with the problem of pyramidal growth in the carapaces of young captive tortoises. Many factors have been incriminated --- dietary protein, calcium, vitamin D, Ca:P, low UVB, rapid growth from high calorie diets --- but to date our information has been strictly observational and anecdotal. One paper published 15 years ago suggested environmental humidity may play a role in pyramidal growth (Weser, 1988, Zur Hockerbildung bei Schildkroten. Sauria 10:23-25). No controlled trials have been done, until now.

A paper has just been published by nutritionists at the University of Veterinary Medicine in Vienna (Austria). Fifty hatchling Geochelone sulcata (siblings and half-siblings from the same farm) were placed in one of five groups that differed in dietary protein and environmental humidity. Protein levels were 14, 19 and 30% crude protein on a dry matter (DM) basis; the diet form was soaked pellets mixed with endive. Extra calcium was provided each group. Humidity groups were arid (24-58%), medium (31-75%) and high (45-99%). Lighting was by three different lights, including UVB-emitting Reptisun 5.0 by ZooMed.

Pyramid humps were quantified by means of measuring the depth and side-lengths of the second and third, and third and fourth central plates on the carapace. Ratios were calculated and termed the H-value (H=hump). Statistical tests included appropriate non-parametric Kruskal-Wallis test and Mann-Whitney U-test.

The study lasted 5 months.

The researchers found that growth rates differed significantly with dietary protein level. Hematocrit and serum levels of calcium and phosphorus did not differ between groups. They found that dietary protein had little effect on pyramidal growth.

However, the researchers found that environmental humidity had a significant effect on pyramidal growth. Sulcata kept in the drier conditions had significantly greater pyramidal growth, and those kept in the highest humidity level had smooth carapaces. Photos accompany the data and statistical analyses.

The authors suggest that under natural conditions, the faster growing hatchlings would be in the humid areas under growing grasses. In contrast, those naturally in dry areas would have no growing grass because of food scarcity, hence have lower food intakes. During food scarcity, there is little growth and probably little bone growth.

Thus, the combination of arid conditions and abundant food is abnormal for young tortoises, yet is commonly found in captivity. However, correction of the problem is not through food (calories, protein) restriction, which can secondarily lead to immune suppression, stunting, debilitation from multiple nutrient deficiencies, and shortened lifespan, but through increasing humidity. When humidity was high, then high food intake, and high dietary protein, did not lead to pyramidal growth.

The authors hypothesize that during dry conditions, dehydration reduces both intra- and inter-cellular pressures on soft cartilage at the areas of bone growth, which could lead to collapse of the soft tissue and subsequent ossification in the collapsed position.

The authors conclude the paper by recommending hide areas of 100% humidity be available to tortoises at all times.

Further work is needed to replicate these results, determine mineral balance (acid-base balance) under dry and humid conditions, and examine the carapacial tissue histologically.

For details:
Wiesner CS, Iben C. 2003.
Influence of environmental humidity and dietary protein on pyramidal growth of carapaces in African spurred tortoises (Geochelone sulcata).
J Anim Physiol a Anim. Nutr 87:66-74. artigo integral (com fotos) http://www.scribd.com/doc/29676196/-sulcatadiet2
outro link sobre o mesmo: http://www.ivorytortoise.com/informatio ... oises.html

[alvesmiguel]

as aquaticas nao teem o rpoblema da humidade visto viverem em agua, o grande problema é a dieta muito rica em proteinas

[ruanda]

Efectivamente, todos os factores que indicas, sózinhos ou associados, podem concorrer para o chamado piramidismo - falta de exercício/falta de espaço; falta de humidade (apenas no caso de crias e juvenis); dieta inadequada (o erro principal); falta de radiação UVB.