While a tortoise’s shell isn’t its “home” in the way many people suspect, tortoise shells are undoubtedly important. When they become injured or infected, the tortoise’s overall health can be compromised.
Accordingly, keepers must monitor the condition of their pet’s shell and do everything possible to ensure that it remains healthy.
In this article, I’ll be sharing some general information about tortoise shells, as well as explaining some of the most common shell problems, and outlining the best strategies for treating problems if they arise.
Shell Anatomy and Health
A tortoise’s shell is essentially an outgrowth of this ribcage. It consists of an internal layer of platelike bones (which are attached to the rib cage and spine) and an external layer of keratinous scutes, which are somewhat similar to fingernails.
The top portion of a tortoise’s shell is called the carapace, while the bottom is called the plastron. The place where the carapace and plastron meet is called the bridge. Tortoise shells have 13 scutes on the plastron and 13 on the carapace.
Interestingly, the bones inside the shell do not line up with the scutes. Instead, they are situated in an overlapping fashion for added strength.
Most healthy tortoise shells are smooth and feel firm to the touch, but the color can vary with species and age, as well as from one individual to the next. Cracks, ulcerations, of localized areas of discoloration (especially when they occur suddenly) can all signal trouble and are cause for further investigation.
A tortoise’s shell is not just a hard, lifeless covering; it’s a living part of their body. This means the shell is sensitive to touch and can feel pain, pressure, and temperature changes.
While the shell is designed to protect tortoises from injuries and predators, if it gets damaged, infected, or cracked, the tortoise can experience pain and discomfort.
Common Shell Problems and Their Causes
While tortoise shells are comprised of thick bone and durable keratin, they can suffer injuries or become infected with bacteria or fungi. A few of the most common health problems that afflict tortoise shells are discussed below.
1) Shell Pyramiding
Shell pyramiding is a problem in which the scutes on a tortoise grow vertically (they should primarily grow horizontally). This results in scutes that are raised and often resemble small pyramids.
The phenomenon of shell pyramiding is not completely understood. Wild tortoises rarely exhibit shell pyramiding, so it is most likely caused by one or more husbandry issues, rather than an illness or injury.
It was initially thought to be the result of improper feeding, an imbalance in dietary calcium or phosphorus, insufficient UVB exposure, or rapid growth rates. But it now seems likely that the problem is related to hydration, as tortoises kept in excessively dry conditions often develop strongly pyramiding shells, while those that are provided with humid hiding spots and frequent baths rarely do.
Aside from the aesthetic problems it creates for keepers, shell pyramiding doesn’t seem to cause quality-of-life issues for tortoises (although it may prevent breeding attempts in extreme cases). This is fortunate, as there is no way to treat pyramiding once it has occurred.
So, be sure to provide your tortoise with plenty of humid hiding spots and adopt a regular bathing regimen.
2) Shell Rot
Shell rot is a blanket term that’s applied to a variety of bacterial or fungal infections that affect a tortoise’s shell.
Shell rot often causes discoloration, and fluid may leak from the affected area. In serious cases, the scutes will begin to deteriorate or slough off completely. These infections can become systemic, which will also cause problems like lethargy and anorexia.
Shell rot can be treated by gently cleaning the wound and applying an appropriate antibacterial or antifungal ointment, though veterinary assistance is often necessary. Additionally, the habitat must be kept clean.
3) Cracks and Injuries
Despite their strength and the fact that tortoises rely on them for protection, tortoise shells are not indestructible – they can occasionally suffer injuries, such as cracks.
Understand that a cracked shell is the same thing as a fractured bone. So, you’ll need to solicit immediate veterinary assistance. Your vet can not only provide pain management medications to limit your pet’s suffering, but he or she may also be able to repair the shell damage.
With proper treatment (and plenty of time – up to 30 months in some cases), cracked shells may heal more-or-less completely.
Preventative Measures for Maintaining Shell Health
The vast majority of tortoise shell problems – including all three common issues mentioned above – are easier to prevent than to treat. Indeed, prevention is the only way to address shell pyramiding; once pyramiding occurs, there is no way to treat it.
The best ways to prevent these problems relate to the manner in which you feed your pet and maintain the enclosure.
Diet and Nutrition
Providing your tortoise with a proper diet will help ensure good bone formation, which will help to keep their shell strong and healthy.
Different tortoise species have different dietary needs. Some need lots of grasses and leafy vegetables, while others will benefit from incorporating root vegetables and fruit in their diet. You’ll simply have to tailor your pet’s diet to meet the needs of the particular species.
However, in all cases, I recommend providing as wide a variety of appropriate foods as is possible. This will help reduce the chances of nutritional deficiencies.
Additionally, it is important that you provide your tortoise with full-spectrum lighting. This will enable the production of Vitamin D3, which is crucial for proper calcium absorption.
Optimal Habitat Conditions
Keeping your tortoise’s habitat in good condition is perhaps the most important step for preventing shell problems.
As discussed earlier, shell pyramiding seems to be caused by hydration issues, so you’ll want to make sure that water is always available for drinking and that your tortoise has access to at least one hide that’s kept slightly damp.
To prevent shell rot, ensure the habitat remains clean and promptly remove feces, uneaten food, and shed skin or scutes. Once per week, clean the enclosure walls with a reptile-safe disinfectant to help keep bacteria and fungi at bay. You’ll also need to completely replace the substrate once every month or so.
It is also important to keep your tortoise’s immune system operating at peak efficiency. The best way to do this is to ensure that the enclosure temperatures are optimal. Minimizing the potential for stress is also crucial, as high stress levels can impair immune function.
To prevent shell injuries, be sure that there are no sharp items in the enclosure and protect your tortoise from predators (if kept outdoors) and other pets. Additionally, always be careful when lifting your tortoise; accidentally dropping him may lead to a cracked shell.
When to See a Vet
It’s always a good idea to seek veterinary assistance when faced with any kind of tortoise illness or injury. Even if the problem is relatively mild, veterinary care will improve your tortoise’s chances of healing fully.
With that said, there are a few cases in which it is especially important to see your veterinarian:
- Your tortoise’s shell is cracked or broken: Because shell fractures likely cause a great deal of pain, they are always emergencies that require immediate veterinary care.
- Your tortoise is exhibiting other signs of illness, such as lethargy: Shell rot infections can become systemic and affect other parts of your tortoise’s body, leading to serious illness.
- Your pet’s shell is soft or malleable: This can indicate metabolic disorders, which will require your vet’s help to treat. While not acute emergencies, these problems do require an exam.
- Your tortoise’s shell has developed a foul odor: This is typically associated with fungal or bacterial infections, which will require medication to treat.
Home Care Tips
Most moderate to severe shell problems require veterinary care, but very minor shell injuries can sometimes be treated at home.
The specifics will vary depending on the nature of the injury or infection, but you’ll generally want to do the following:
- Clean the area with soap and warm water. Once you’re finished, gently dry the area with clean, lint-free paper towels.
- Apply a small amount of triple antibiotic to open wounds. A cotton swab usually makes a good applicator.
- Ensure that the habitat is impeccably clean. It is vital that your tortoise is not exposed to additional bacteria or fungi while recovering.
It may also be wise to pause your tortoise’s bathing regimen while his injury heals.
Long-term Management and Monitoring
In the weeks, months, and years following your tortoise’s shell problem, you’ll need to monitor the affected area regularly. If you notice it worsening, contact your vet at once.
Remember that tortoise shell injuries often take an extraordinarily long time to heal, so you’ll need to be patient.
Some Final Thoughts on Tortoise Shell Health
Keeping your pet’s shell healthy is an important part of general tortoise care. You’ll need to do as much as you can to help prevent injuries and infections from happening by providing the best husbandry and diet possible.
But, if you discover that your tortoise is experiencing a problem with his shell, be sure to address it promptly. This will give him the best chance of recovering and living a long, healthy life.
Remember, tortoises are unable to live without their shell and it is not removable. It’s a fundamental part of their anatomy and is attached to the animal’s ribcage and spinal column.
Citations and References
- Merck Veterinary Manual – Disorders and Diseases of Reptiles
- Canadian Journal of Zoology – Detection of multiple paternity and sperm storage
- Turtle Rescue of Long Island – Common Health Problems
- Improve Veterinary Practice – Shell injuries in tortoises
