Reptile & Amphibian Forums

Hello,
My 10 year old Spiny tailed Igauana (Ctenosaura similis) has started opening her mouth periodically and keeping it open until I disturb her. I know it's not a defensive behavior or high temps because she is tame as can be and I know when she is upset. I catch her doing it when no one is in the room and I saw her doing it while she was sleeping under her shelter which is cool or other cool areas of the cage. I don't hear respiratory noises or see mucus anywhere in her mouth. She otherwise is very healthy and eating well.
Is there another reason this can be happening or is this a normal thing for senior aged igs?
Thanx,
John Styner

I havn't kept this species, or any close relatives, so cannot say if it's normal. It does sound to me like it is abnormal... aging itself should not cause behavioral changes like this. My suggestion is to check the iguanid forums to see if the behavior is abnormal, and then assuming it is, have a vet Xray (or perhaps prefereably ultrasound) the lungs and/or do any other diagnostics that are deamed necessary after the examination.

Ian

Hello everyone,

I was reading your case and found it to be pretty unique. Please understand that I'm only a student and that I am not a licensed veterinarian, however I may be able to offer you some insight into this problem. There are a variety of disease conditions that may cause an animal to mouth gape. although I would need specific temperatures taken from the terrariums gradient extremes to help rule out environmental factors (in addition to humidity levels) at a time when the animal is exhibiting mouth gaping to help rule out environmental factors. It appears to me that you have quite an understaning of this and still your iguana seems to be mouth gaping at night during a time of decreased activity/rest when a veterinarian would least expect this symptom to occur in a healthy individual.

I would say the following list of presemptve causes may be possible! I would advise that you see a licensed veterinarian ASAP and follow the order of this list of differentials (or what your vet recommends first).

Infectious (bacteria, fungi, viruses (saurian herpes & adenovirus)) (MOST LIKELY CAUSE)

Heart disease

Non-infectious lung disease

or a space occupying mass such as a tumor

although less likely, I would still keep neurological disturbances on the list of possibilities (differentials) given that central tumors in the brain can affect the cardiac and respiratory centers of the brain stem.

although unlikely, renal failure may also present in this fashion due to the toxic effects of systemic ammonia buildup

Anyways I hope this helps! please don't wait to see a vet! Mouth gaping is a progressed clinical sign in reptiles! Good luck

Also one other though, is your spiney tail a confirmed female? and if so when was the last time (if ever)that she was exposed to a male? You may also check to see if she is gravid? eggs can also be compressive within the body cavity and may affect the lungs.