Parasites can be a problem in tortoises, especially if they are kept outside. This is generally a good way of housing them as it is more natural than an indoor environment, but this has to be balanced against the possibility of a build up of worms and other parasites in the areas where the tortoise lives or is allowed to roam. Most people keeping tortoises keep them in a run of some kind, but this needs to be moved very frequently to avoid the area becoming totally infested with the oocysts of intestinal worms which can live outside the body for long periods and in quite challenging weather. As long as your tortoise is healthy, a number of parasites is acceptable and almost unavoidable, but if it becomes unwell with another health problem the opportunistic parasites can multiply alarmingly quickly, making the original condition far worse. It is always a good idea to treat parasites whenever they are first seen.
Ectoparasites – parasites on your tortoise
The most common parasite you will encounter living on your tortoise is the tick. It might not be obvious although ticks do tend to cluster around the mouth and eyes, where the blood supply is easier to reach, so with luck you might see it or them almost as soon as it has attached. Ticks need to be removed as a matter of urgency as they can transmit some very nasty protozoan conditions, but apart from that they can make the tortoise very anaemic and depressed. Removal needs to be done very carefully by using tweezers and pulling backwards without jerking away from the insect’s head. If the mouth parts are left in it can cause a nasty lesion which can be difficult to resolve.
A very big word of caution here – if you have other reptiles along with your tortoise do not be tempted to treat it with the ivermectin your vet may have prescribed them for tick removal. It is totally toxic to chelonians and there is no doubt that if you give any to your tortoise it will die. Mites are also sometimes found on tortoises and these can usually be brushed off if found in small enough numbers. If the infestation gets a hold, there are various treatments but they can be toxic in the wrong amounts so advice from your vet is essential before starting any treatment.
Endoparasites – parasites in your tortoise
Tortoises are prone to intestinal parasites and if this has been a problem in the past it is a good plan to have your animal wormed twice a year, once before hibernation and again when it wakes up. This is not a procedure that is really possible for a layman to undertake so it will need a trip to the vet. Some worming products are toxic to tortoises and so should not be used and it is also best if they are delivered directly into the stomach.
Prevention is certainly better than cure in the case of intestinal parasites in the tortoise and it is relatively simple to do this. If your garden is not large it might be difficult to move the run often enough to prevent the build up of parasite eggs, but it is possible to reduce the amount of faeces the tortoise delivers to your lawn. If you bathe the animal in warm water it will probably pass its faeces then and as long as you are then quick to remove the animal and rinse it off, the worm eggs will not transfer to its feet or tail and then to the grass. If you do this regularly, the numbers of eggs per metre will be reduced to below danger level. It is still a good idea to have your tortoise’s stool checked before hibernation so it can be tucked up for the winter in the best possible health.
What to watch out for
Endoparasites are usually quite obvious, but it is still important to check your tortoise over for unwanted visitors on a regular basis. Mites tend to hide in creases of the animal’s legs and inside the shell so it is particularly important to check there. If the skin is broken by itching or a large infestation it can cause a nasty ulcer which can be slow to heal. Ticks are probably the most obvious parasite of all and can be dealt with either with medication or by manual removal. If you are at all squeamish about pulling the tick out it is best not to start; your vet will be more than happy to do it for you. When you have removed the tick, drop it into some alcohol to kill it. Don’t squash it in your fingers – some ticks can transmit some very nasty diseases which are dangerous to humans, such as Lyme disease.
There are recognised areas where Lyme disease is found in the UK, but it is wise to take precautions even if you live outside the area. If your tortoise is suffering from worms, it will probably have very loose stools. It will also probably be very lethargic and appear to be quite depressed. Despite the old wives tales about feeding a worm and therefore eating more, it will probably be off its food as well. A visit to the vet is really the only way to resolve a case of intestinal worms in a tortoise and if hibernation season is near it should be done as soon as possible.
Parasites are defined a anything which lives in or on another organism, deriving benefits from the proximity at the host’s expense. Mites are not therefore strictly parasites, but are usually counted as such. Other insects which are often considered parasites, such as flies, are certainly not parasites, although fly strike – when maggots hatch from eggs laid on the tortoise’s body, usually in a wound or around the anus – can easily be fatal if not dealt with immediately.