Obesity is a significant problem in captive chameleon populations. We love our pets and feeding our pets is not only fascinating for us, but is a sign of that love. We would never let our pets go hungry! And this well intentioned action actually creates an unhealthy situation where our chameleons become overweight and unhealthy. In gravid females it can be deadly. The large fat pads become life threatening in females when they grow so large that they make it difficult for the large eggs to make their way through the oviduct and to the laying nest. This is a form of egg binding.
The preventative measure is simply to feed sparingly once they are done growing. An effective feeding schedule is
0-3 months: Feed ad libitum. This means food available all the time. The job of a baby is to grow as fast as possible. Provide them with well gutloaded feeder insects ad the appropriate supplementation for the species.
3-6 months: Feed as much as they will eat every other day.
6-12 months: Feed 10 food items every other day
12+: Feed five food items every other day and skip the weekend.
Female Veiled Chameleons are a special case in that we want to be extra careful to keep them lean. They are driven to eat anything they can to get big quick because they have to mature, mate, and lay eggs before the dry season comes and kills them all. So there is no time in a wild veiled chameleon’s life in Yemen that they ever live long enough have to worry about obesity. So, in captivity we have to be very careful not to feed them everything they will eat. They can easily get too fueled and produce ridiculous sized clutches of eggs with fat pads that may make laying difficult.
I use the following schedule for female Veiled Chameleons
3-6 months: Feed 5 food items every other day
6+ months: Feed three food items every other day and skip the weekend.
In all cases, learn where fat deposits are made on your chameleon species and adjust your diet with respect to whether you see the fat storage being filled up.
When eating more than they need, the chameleon’s body will store fat in various places including the casque, the overall body cavity, and the internal fat pads. These areas will take on a softer appearance. Below is a set of reference images that show a healthy shape and an obese shape.
In this necropsy you can clearly see the fat pads in the deceased female Meller’s Chameleon. The orangish, creamy colored objects to the hind end (left side of image) are the fat pads. When these are filling the body cavity in back there isn’t much room for relatively large eggs to squeeze through.
Treatment for an overweight chameleon is simply to cut back the diet to the recommended amount. You can even skip a feeding in that new schedule if there is a massive problem.
The most likely place you will need vet involvement is if you have a female chameleon and she is having problems laying her eggs. You may need to have the vet extract the eggs.
Nutrition is very important as it is with all living beings. Make sue that all the feeder insects are on a strong gutload schedule and are supplemented appropriately. And then give enough to sustain life, but not to overfeed. Chameleons can easily go a week without food. They do not burn many calories just sitting there doing what a chameleon does! Keep your chameleon lean and keep their food nutritious.