Egg binding is a condition where a female egg laying animal is due to lay her eggs, but due to some sort of complication, is unable to do so. This results in the eggs remaining in the body.
This can affect any egg laying animal; from chickens, turkeys and ducks to snakes, lizards and tortoises.
There can be various causes to egg binding..
One cause is where the egg is too large to pass through the pelvic canal and be laid. This can happen due to the development of an abnormally large egg, or conditions where the pelvis has been damaged and even normal sized eggs are unable to pass through and then be laid.
A second common cause of egg retention is related to behavioural stress. Many chelonians will not deposit their eggs if their habitat is not correct for oviposition (egg laying). Quite often incorrect housing, substrates and temperatures will inhibit animals from building nests and subsequently prevent them laying eggs!
Many times, once presented with the perfect environment the animal will happily build a nest and deposit the eggs without further problems. Other times they need some medications to help them along.
Other factors involved with egg retention include improper nutrition, diseases such as cancers, and previous egg binding that has damaged the uterus.
Retained eggs must be removed because if left they can cause serious disease, and even death. This is why egg binding is a serious medical condition and should be attended to immediately!
Troublesome Tortoise Eggs – Mrs T’s story
60-year-old Greek Spur-thighed tortoise, Mrs T, was brought in to see us because her owner was concerned about her. When the vet examined her, he was reassured to find that she was very bright and well in herself. However, Mrs T’s owner explained that she had laid two eggs the previous week, but had not produced any more since. The vet suspected that Mrs T may be carrying more eggs, which she had been struggling to deliver.
Mrs T was admitted to our hospital ward so that we could find out what was going on. When an x-ray was taken it clearly showed eight well-formed eggs in her uterus. The vet then gave Mrs T a drug designed to encourage her body to deliver the eggs naturally, with the hope that this would avoid the need for surgery to remove them.
Surgery of this type is particularly tricky in tortoises because, before the main procedure can be carried out, a flap needs to be cut in their plastron (the plastron is the hard shell covering the underside of the tortoise’s body).
The protective shell of a tortoise is made up of fused bone; it is a protective armour designed to keep predators out and so a surgical saw is required to cut through the shell. The vet has to be very careful when cutting through the shell as they don’t want to cause any injury to the tortoise’s delicate body underneath. We hoped that Mrs T would respond well to the drug we had given and that we would be able to avoid putting her through the extra trauma of surgery.
Our nursing team settled Mrs T into a comfy nest box that they had made for her and, to everyone’s relief, she started to lay her eggs almost right away.
Over the next half an hour Mrs T managed to lay all eight of her calcified eggs successfully and was able to be returned to her owners.
Mrs T is now happily back at home and quickly returning to her normal self,
well done, Mrs T!