Temporal Gland Infections and the Average Keeper
Authored By Elise Stein | Chameleon Enthusiasts
This gland is found only in the Trioceros genus. It is a flat pocket located above the angle of the mouth
Are you familiar with the words “Temporal Gland”? How about TGI?
Odds are, you probably skimmed through an article here or there, or saw it mentioned on forums and groups. But if you had to answer the question
“What IS a Temporal Gland”, or “What is a Temporal Gland Infection”, you wouldn’t quite know where to begin, would you?
I found myself asking that question, after it was already too late. A few months back, I discovered my beloved Jackson’s Chameleon had this very infection, and it required immediate attention. I decided I needed to dig a little deeper to find out WHY this was happening, how to treat it, and how to possibly prevent it.
What is a Temporal Gland? What is a Temporal Gland Infection?
First sign of tgi slight swelling near corner of mouth.
This gland is found only in the Trioceros genus. It is a flat pocket located above the angle of the mouth. It is exocrinous, meaning it secretes its products through ducts into the outer cells, rather than into the bloodstream.
The secretion is basically dead cells which become infected by bacteria and decay, leaving a waxy yellowish/whitish substance giving off a very pungent smell. This cheese like substance has two purposes; to deter predators by smell, making them think they are toxic, and to attract flying insects by smearing the substance onto a branch.
Because of the lack of information on this issue, the cause is often speculated, and I had a terribly difficult time narrowing down a definite answer amongst Veterinarians, breeders, keepers, and experts. Some believe Temporal Gland Infections are due to a weakened immune system due to lack of Vitamin A. Others believe it is due to improper feeders, over-supplementation and improper living conditions. Unfortunately for this genus, they seem to be rather prone to this type of infection. Many keepers agree they noticed this issue in adult males after certain feeders were found lodged into the glands during feeding, unable to come loose. Others noticed a wax-like buildup along the glands and gums. What I’ve gathered from my research, is there are only a few known publications (listed below) with real information on Temporal Glands and their function. Regardless, I knew I had to take a different approach to the husbandry of this particular species.
Then, in experiments with houseflies, they showed the insects were strongly attracted to the pouch contents
Publication #1
“In the 1960s, Ogilvie observed chameleons wiping their jaws against tree branches, smearing a foul-smelling, waxy material on the bark. And he spotted a small pouch near the corners of the chameleon’s mouth where the material seemed to come from. Based on his experiments, Ogilvie suggested that the pouch contained the remains of sloughed off skin cells and rotting bits of food and that chameleons might be using the putrid substance to lure prey closer.
“If you think about it, it makes sense to be able to do that,” said Preest. “Chameleons spend a lot of time in trees, and their amazing tongue, which can shoot out a distance of about two body lengths, is really helpful. But if you can also do something to bring the prey to you, then that’s going to increase your feeding success.”
“[The substance] gets noted a lot briefly, and people say more work needs to be done here,” said Christopher V. Anderson, a researcher at Brown University who has studied chameleons and wasn’t involved in the study. “It’s amazing that nothing had been done since the ’60s.”
Meanwhile, other scientists had raised questions about the material’s origin, suggesting that it might be secretions from glands rather than decaying matter.
Intrigued, Preest and her colleagues — undeterred by the odor — decided to pick up where Ogilvie left off.
After studying the pouch tissue, the researchers found no evidence of a gland, but did find layers of sloughed off skin cells, collecting and aging in the pouch, they wrote in a paper published in Physiological and Biochemical Zoology this month. They didn’t investigate the role of food particles but given their observations of how parts of the pouch open and close as the chameleon eats, it’s likely that crumbs of prey also get trapped, said Preest.
Then, in experiments with houseflies, they showed the insects were strongly attracted to the pouch contents — almost twice as many flies moved toward the material than away. In control trials, the flies buzzed around haphazardly.
Following Ogilvie’s suggestion, the researchers also used a technique known as gas chromatography-mass spectrometry to identify four of the mixture’s chemical compounds. Surprisingly, they found those compounds are similar to ones in insect pheromones, which bugs use to attract mates, for example.
The idea that “chameleons are using chemicals that mimic pheromones to attract prey items, is a really cool finding,” said Anderson
“It looks like the lizards have somehow capitalized on this form of communication between the insects, and they’re turning the tables on the insects and luring them to their deaths,” said Preest.
The idea that “chameleons are using chemicals that mimic pheromones to attract prey items, is a really cool finding,” said Anderson. “It shows how complex the feeding strategies for these animals really are.”
Still, that may not be the whole story. “We don’t know if it’s actually those compounds that are attracting the flies, or if it’s just that the material is really smelly and disgusting,” said Anthony Herrel, a biologist and research director at the French National Centre for Scientific Research who wasn’t involved in the study.
We know flies are attracted to decomposing bodies because they can lay their eggs there, he said. “So the link between the actual compounds and the pheromones is something we can’t make a very strong case for yet. But what they showed is very suggestive and interesting, and it should be followed up on.”
Preest and her colleagues did try to locate Ogilvie, she said. “But he passed away in [2002], so we weren’t able to give him a copy of this work. That would have been fun.” https://www.insidescience.org/news/why-chameleons-sometimes-smell-rotting-meat
The odor of this substance was similar to that of decaying meat.
Publication #2
“This problem became apparent during a field investigation of the genus Chamaeleo conducted in east and central Africa. Many of the animals that I collected exhibited a white, foul smelling, viscous substance at the angle of the jaw. The odor of this substance was similar to that of decaying meat. When the jaws were opened, the quantity of the substance increased. After examination, it was found to come from a pouch or fold of skin located dorsal and median to the upper lip at the posterior junction of the lips. At first, I thought this was the secretion of a gland and I kept records in order to determine if the “gland” was active only during certain periods of the year. I soon found that it was “secreting” at all times. This led me to believe that perhaps this was something other than a gland; therefore, I undertook dissections. 1 found that there was neither obvious glandular material lying adjacent to nor ducts leading into this pouch and that the only glands near this region were salivary glands. Upon microscopic examination, 1 found no tissues that were glandular in nature associated with this pouch. Observations on the behavior of these animals in the field led me to believe that certain of their behavioral patterns were related to this same pouch. A detailed search of the literature led me to conclude that no one has previously described these pouches nor discussed the function of their product. I found many papers that were concerned with the anatomy of Chamaeleo— particularly with reference to specific systems. However, in none of these papers is there any discussion or description of such a pouch. This led me to the conclusion that this is a previously undescribed structure deserving of a certain degree of investigation.”
https://shareok.org/bitstream/handle/11244/2104/6614238.PDF?sequence=1
Publication #3
“The development of the temporal pouch varies considerably across the family. According to Ogilvie (1966), the pouch has been observed to varying degrees of development in Bradypodion, Chamaeleo, Kinyongia, Rieppeleon, and Trioceros, but it is absent in Calumma, Furcifer, and Rhampholeon. More recent work by Preest et al. (2016) found it to be developed to varying degrees in Chamaeleo, Furcifer, & Trioceros. While the pouch is present, however, that does not necessarily mean it is acting as an exocrine gland in all these genera. It may or may not be producing or secreting the same substance in all these taxa. That has really only been studied in Trioceros, which do seem to have the best developed pouch.”
The Biology of Chameleons edited by Krystal A. Tolley, Anthony Herrel
The moment I noticed something was wrong.
Southern California, mid-August: I was out back observing our chameleons just before the sunset. I house all of my chameleons outdoors and strongly believe there’s nothing better than natural UV. I did my rounds as usual. I peeked in on each one, snapped some “pj” photos, and noticed something slightly off on our two year old, Jackson’s mouth. There was a small protrusion located near the corner of the mouth appearing inflamed. I remembered reading up on health issues months back and started to brush up on the signs of a Temporal Gland Infection again. I contacted a few people whom I consider experts in the field and asked for their opinions, only to hear what I had already assumed- it looked like a TGI. I immediately made an appointment at my local veterinary office to have him checked out and the doctor confirmed our suspicions: it was indeed a TGI.
The veterinarian came back with a course of action. We started up Fortaz-ceftazidime injections given every 72 hours for 3 weeks. Over the next several days I began to seek out advice and suggestions from other keepers who have experienced this issue, but I didn’t take the time to understand WHAT exactly I was dealing with. The infection seemed to have cleared up after first course of antibiotics…seemed to.
Temporal Gland Infection Return
Surprise! The Infection is back!
It was mid-September, and I was feeling like a pretty seasoned and confident keeper. It appeared as though I’ve been able to treat a serious infection taking the lives of so many other captive chameleons around the world. I was confident I had it all figured out.
I was wrong.
Symptoms of the infection appeared again, significantly more swelling, inflammation, and a swift decline. We went in for a follow-up with the vet, but this case was a little more complicated than the last. It appeared the gland was not able to drain and would require immediate surgery. This involved lancing the area and removing pus and debris.
This was the first time any of my chameleons had to undergo surgery, and to tell you it was nerve-wracking is an understatement.
A few tense hours later he was out of recovery and ready to come home, where we proceeded with the new course of action for treatment. We begin round two of Fortaz-ceftazidime Injections, daily Silver Sulfadiazine ointment on the wound, oral Metacam for the swelling and pain, and Manuka honey for the open wounds to help stop the infection. In order to be successful with oral medications, you really have to be comfortable forcing the mouth open by gently pulling on the Gular. You must be able to give injections safely and calmly, which will take patience and practice. Absolute diligence is key.
Making Changes.
With the help of some incredible people in the Reptile Community, I started rethinking my entire approach. I started cleaning the glands daily and flushing debris away with saline solution. By doing this, I decrease the odds of debris causing infections. I stopped feeding things like Hoppers and Mantis with long legs which can become lodged into the gland(s) and in the corners of the mouth. I started offering smaller, less messy feeders like flies, a variety of smaller roaches, and stopped offering large prey items. Upon further research, I implemented Bee Pollen in my feeder’s gut-load. Bee Pollen is full of protein, amino acids, vitamins, minerals. It is the only substance that contains every element found in the body, and makes an excellent supplement. Another huge factor in eliminating health risks is also to limit your time handling your chameleon(s). As hard as it may be to avoid snuggling them, taking them on little walks, or simply holding them, the best thing to do is let our chameleon be. Stress is extremely detrimental to the health of every genus of chameleons, getting to know the signals of stress is incredibly important.
One treatment factor I strongly feel made a huge difference this time around was the use of Manuka Honey. Thanks to Cheryl Garcia (a wonderful Exotic Rescuer, Another Chance Sanctuary | To serve, protect, rehabilitate, and find …) I was able to get my hands on some of this (after confirming with my veterinarian it was safe).
Manuka Honey is produced in New Zealand by bees that pollinate the Manuka bush. It has many healing properties and has been used for medicinal purposes for thousands of years. It was often used as a drawing salve to treat infections. It is Bacteriostatic , which means bacteria cannot thrive in this environment due to an acidic PH of 3-4. Bacteria needs a PH of 6-8 to reproduce. It assists in removing debris by pulling fluid from the Lymph layers and leaves the wound clean. It also reduces inflammation by stopping the presence of bacteria. I used this honey daily during treatment inside the mouth, directly on the gland/wound to promote healing. Unlike the first time, I noticed that Tre was eating on his own immediately after surgery. It is my belief that the honey provided a soothing relief.
Are we in the clear?
I have been told once a chameleon develops this type of infection, it almost always recurs over the course of their lifespan. As of today, mid-October, we have been cleared of all signs of the infection. Tre is a healthy weight of 100 grams. He is very active, alert, and is an avid hunter. I believe if I had not re-assessed my approach to husbandry for this species, Tre would not have been able to overcome the infection.
The gravity of truly appreciating the biology of these creatures and familiarizing ourselves with signs of illness, treatment, and prevention cannot be emphasized enough. Proper lighting, supplementation, temperatures, and humidity are vital to the success of keeping healthy specimens. As is the willingness to seek out licenced veterinary assistance as soon as you notice something may be off.
Always make sure to have emergency supplies on hand. I found gloves, saline solution, syringes, iodine, Silver Sulfadiazine ointment, Manuka honey, and Q-tips to be the most useful items in my daily treatment routine. I would like to someday see the price of these chameleons reflect the difficulty keeping them. Maybe then we will see a decline in impulse buys often leading to illness and in some cases, death. I now understand why so many people warned me of the difficulty with this species; a challenging, yet rewarding privilege.