Last Updated on October 6, 2023 by Samantha Harris
Egg binding occurs when a gravid tortoise can’t lay her eggs. This means the eggs remain trapped inside the body with life-threatening implications.
The eggs can lacerate bodily tissue, causing internal bleeding and infection. Also, egg matter released within the body can cause inflammation and bacterial infection, leading to egg yolk peritonitis.
If eggs remain inside the body for too long, permanent damage can be caused to the reproductive tract, meaning the female can no longer reproduce.
What Is Dystocia in Tortoises?
Egg-binding and dystocia are interchangeable terms when referring to female oviparous animals. Dystocia is defined as abnormal labor or difficult birth.
Egg binding is a more specific term for dystocia. Another term commonly used is ovostasis (the scientific term for egg binding).
Pre-ovulatory vs. Post-ovulatory-follicular Stasis
Pre-ovulatory follicular stasis is when the follicles haven’t reached ovulation. If the follicles don’t ovulate and remain attached to the ovary, this can lead to infection and inflammation.
Post-ovulatory follicular stasis (egg binding) is when tortoises can’t lay one or more fully developed eggs, so they remain stuck inside the reproductive tract.
What Are The Causes of Egg Binding in Tortoises?
There are many reasons why a tortoise can become egg-bound, including the following:
Carrying eggs means tortoises have less space for food storage. Consequently, females eat less or forego food, making them more susceptible to nutritional deficiencies.
Without sufficient calcium, a tortoise’s eggshells may become fragile and brittle, making it hard to pass through the reproductive tract.
Calcium is also essential for smooth muscle contractions that help move the eggs through the oviduct and out of the cloaca, which is the exit for the digestive, urinary, and reproductive systems.
This issue can be resolved with calcium-rich foods, like kale and dandelions, and nutritional supplements.
Egg binding can occur because the tortoise’s eggs are too large to pass through the pelvic canal due to an unusually large egg or damage to the pelvis.
A tortoise with an injured pelvis may not be able to pass an egg. Sometimes, a tortoise is born with a pelvis that’s unable to pass eggs due to its anatomy.
Some tortoises won’t lay their eggs when they don’t think it’s a good place to do so. This could be due to the wrong substrate, temperature, humidity, or lighting.
When the enclosure isn’t suitable for laying eggs (oviposition), a tortoise won’t lay her eggs until whatever problematic issues have been corrected.
Sometimes, an egg-bound tortoise may repeatedly build and destroy nests because it can’t find a suitable place to lay its egg. However, this behavior is relatively common in all tortoises.
Illness and Disease
Egg retention in tortoises can also occur due to reproductive tract damage and diseases, hormonal imbalances, nutritional deficits, and poor overall health.
Diseases can make organs unable to function, or a sick animal may be too weak to lay an egg.
How To Know If A Tortoise Is Egg-Bound
The egg-laying process takes several hours to several days to conclude, depending on the species and the number of eggs. The average clutch comprises 4-8 eggs but can be larger.
The tortoise could be egg-bound if the egg-laying process is particularly slow, especially if it stalls.
Most symptoms egg-bound tortoises experience, at least during the early stages, are shared by most gravid tortoises. Here are the main warning signs of dystocia:
A tortoise may be egg-bound if she can’t find a place she considers suitable to lay her eggs. While this can be a false flag, it signifies that a tortoise is somehow inhibited from laying eggs.
Restlessness is among the first symptoms egg-bound tortoises experience. Compared to other symptoms, it’s not as concerning, as the tortoise may find a suitable nest and lay her eggs.
Repeated Attempts To Dig
This symptom can be a false flag, as many gravid tortoises are selective with their nests. Some tortoises will have difficulty finding the perfect area for their eggs and may attempt to dig up a nest.
You can assist if you observe a tortoise digging a lot. You can provide a more suitable substrate, check if the habitat is warm and humid enough, and ensure it receives enough light.
Straining And Swollen Cloaca
The tortoise may have a swollen or distended abdomen that feels hard and lumpy.
Tortoises lay eggs through the cloaca. If the eggs are bound, you may notice straining. Eventually, the cloaca will become swollen due to the pressure the eggs place on it.
Infection can lead to cloacal redness and discharge. If so, tissue could protrude from the cloaca.
An egg-bound tortoise can experience a lack of appetite or may stop eating entirely. Eggs take up vital space inside the shell, causing considerable pressure, which can lead to inappetence.
Inability To Pass Waste
An egg-bound tortoise will struggle to pass stools, straining or pushing without success. As the cloaca houses the urogenital and digestive systems, a tortoise may no longer be able to go to the toilet.
Consequently, the tortoise produces a small amount of poop or nothing at all. Tortoises should poop at least every 3 days, so it’s a warning sign if no waste has been produced in 4+ days.
Of course, a tortoise that isn’t eating has limited feces to pass.
Depression And Weakness
During the later stages of egg binding, a tortoise may become extremely weak and depressed.
Attempting to lay the eggs will strain the tortoise, and complications like illness, malnutrition, muscle atrophy, and bacterial infection can lead to overall physical weakness.
How To Treat An Egg-Bound Tortoise
If you’re concerned that a tortoise is egg-bound, it should be immediately examined by a herp vet.
A vet must confirm dystocia through a physical examination and blood tests. Vets will perform an X-ray to verify the condition and location of the eggs.
If the eggs have been present for a while, a radiographic examination will reveal a rough and irregular shape, while normal eggs should be oval-shaped with an opaque shell.
Egg-laying may be induced by injecting oxytocin (a supportive therapy) if the tortoise has recently become egg-bound. Repeat dosages of oxytocin may be provided at 4-6 hour intervals.
In severe cases, a vet will perform surgery (salpingostomy or ovariosalpingectomy) to remove the eggs. Unfortunately, this can adversely affect the tortoise’s chances of future reproduction.
IV fluids and nutritional supplements will be provided to prevent malnutrition and dehydration.
Providing sufficient warmth and humidity can create the optimal environment for egg-laying. A warm, damp towel or a shallow tub of water to bathe in can also help the tortoise to relax.