Shell Rot in Turtles & Tortoises

Shell Rot in Turtles & Tortoises

Fungal and bacterial organisms have been associated with the condition known as shell rot. Small scratches or abrasions provide entry for these organisms. As they take hold in the living bone beneath the keratinous covering of the shell, they begin to erode the bone and may penetrate into the body cavity, causing serious, even fatal, systemic infections.

Initial home care for non-penetrative lesions
If the area of infection has not yet eaten through the shell, you can try initially to treat it at home while at the same time assessing the care setup to figure out why the defect occurred to begin with that enabled the fungal or bacterial organisms to get started.

The infected area should be swabbed with a dilute povidone-iodine solution. The areas of infection can then be gently scraped away using a blunt edge such as a disinfected table knife. The scraped areas are then swabbed with povidone-iodine solution or ointment.

Since you don't know if the infection is bacterial or fungal, first try a topical antibiotic ointment, such as a triple antibiotic ointment, which contains three different broad-spectrum antibiotics. Dab a bit on the infected. If the chelonian is an aquatic turtle, keep the turtle out of the water for at least 10 minutes to give the medication time to penetrate. If there is no observable improvement within a couple of days, try an antifungal cream. There are several available, each with a different active anti-fungal ingredient. Try one, keeping aquatic turtles out of the water for at least 10 minutes to give the drug time to penetrate. If there is no improvement after a couple of days, take the chelonian to your reptile vet. These infections are not something to mess around with for very long at home, given the potentially lethal nature of systemic infections.

How do infections get started?
When fungal and bacterial shell infections occur, they are usually found in aquatic turtles. Pits of varying size and depths have also been found in terrestrial chelonians, typically the result of the animal being preyed upon by invertebrates while in hibernation. When the shell is scratched or punctured, even if it does not penetrate all the way through the shell, it is like getting a scratch or puncture wound on our skin: a defect is formed in which bacteria or fungi can collect and grow, causing infection. In the wild - and captivity - this can occur by rubbing up against a too-rough surface, falling on or against a sharp object, or being preyed upon (or being used as a chew toy).

In the case of aquatic and semi-aquatic turtles, the situation is complicated by the water quality. Depending on the situation, dirty water can cause the infection, or can exacerbate one. Keeping the water clean is essential in helping to prevent health problems and to aid - or at least not hamper - recovery when illness and shell infections occur. When your chelonian has an infection, you also need to clean and disinfect the tank and keep the water clean by use of a regularly serviced filtration system and frequent water changes.

When you need a vet
The bottom line is your chelonian's health. What may look to you like a minor infection may be the tip of a much more serious problem. A shell or skin infection may be a primary problem, or may be secondary to an underlying, more serious, health problem. If there is a change in the chelonian's daily routine and behavior, that is yet another sign that something more than a minor superficial infection is happening.

So, don't try treating a non-penetrative lesion on your own for more than a week. If you can't tell if the lesion penetrates through the shell, or the lesions grow or new ones appear, don't wait even that long: get your turtle or tortoise to your reptile vet. If there has been penetration into the body cavity, the cavity will need to be flushed out, checked for possible parasites and infection, and the veterinarian may determine that a course of systemic antibiotics is indicated. Deep erosions may need to be sealed with patches similar to those used to repair broken shells after the underlying tissues have been cleaned and the chelonian treated systemically.

Talk with your vet about how to keep your aquatic turtle during its recovery period. You may need to keep the turtle dry and out of the water as much as possible, allowed in daily to feed, drink and defecate only.