Plantar Irritations, Infections and Lesions in Chameleons
Amongst all spectacular adaptations on ther arboricolous lifestyle, the Chameleons possess very special feet. As their arrangement is absolutely unique amongst all vertebrates, it is called chamaeleodactylous (not zygodactylous, as previously erroneously assigned). Their fingers are fused in groups of 2 or three in a pincer-like formations to build a flat and usually whitish colored, very smooth plantar/palmar side, equipped by variously developed microstructures, analogical to setae in geckos and anoles. These specific morphological feature support all their ability to grasp firmly the twigs, on which they predominantly live and move safely through their arboreal environment.
Due to their fine and complex structure, they are vital for chameleons and any disturbance of them causes negatively influence their ability to move safely in the canopies, which leads to discomfort and stress and can have lethal consequences...
IN THE WILD
In the wild, the chameleon soles are usually flawless, whitish, shed and clean. In some older specimens, it can be sometimes contaminated by dust or soil from the surrounding environment.
Within my 35years of research in the wild, I have noticed only four occasions of irritated soles of chameleons:
- Furcifer petteri, Montaigne de Ambre, Madagascar: a male found sitting on the introduced Mexican Weeping Pine, Pinus patula (originally from Mexico), with sap-contaminated soles unable to shed, inflamed and partly teared to bloody lesions. The tree is well known to bleed its quite liquid sap, which is very gluey initially and hardens to form more or less sticky fields on the trung and branches.
- Kinyongia multituberculata in Lushoto, Tanzania: several specimens found on the Caribbean Copper Plant, Euphorbia cotinifolia (originally from Latin and Southern America), with soles and parts of the bodies contaminated by the white latex-sap. The animals were lethargic and might have suffered the toxic influence of the sap. The plant is very fragile and richly bleeds latex/sap from wounds. Even several tens of grams weighing chameleons break the leaves and their terminal branches easily.
- Kinyongia multituberculata in Lushoto, W Usambara, Tanzania: several specimens found with bleeding lesions on soles at the grounds of Lushoto Executive Hotel, where the walls and big trees are overgrown with the introduced Creeping Fig, Ficus pumila (originally from East Asia) and Common Ivy, Hedera helix, (originally from Europe and Western Asia). The Creeping fig is known to have a toxic sap, the Ivy is famous by being rich in Oxalates forming very sharp crystals.
- Kinyongia matschiei in Amani, E Usambara, Tanzania: a male specimen found in a bamboo plantation (probably introduced Fargesia sp. from central Asia) with bleeding soles. The sharp edged serrated leaves can cause cuts in heavy specimens that slip on the smooth leaves, moreover, sharp microfibers loosened from the stem can stick in the soles and cause contamination, inflammations.
- Chamaeleo calyptratus in Miami and and in Fort Myers, Florida, USA (introduced feral populations) found on the invasive introduced Brazilian Peppertree, Schinus terebinthifolius (originally from Southern America) with sap-contaminated soles. The sticky sap is known to be able to cause contact dermatitis and in general the plants is toxic.
IN CAPTIVITY
In captivity, problems with soles are much more frequent than encountered in the wild and then believed and recorded. The reason is simple: the chameleons do not expose the soles under normal circumstances to the outer world: either, they are in touch with the branches or they are quickly moving folded like a pincer to unfold and grasp for the brach in the last break of seconds. Therefore, even heavy problems become visible only in case of a thorough inspection which is mostly not done in chameleons, as they are - with good justification - considered a no-touch-animals.
Nevertheless, for many reasons discussed below, the plantar disorders reach from light irritations visible usually as pink-colored areas of palms and soles, over inflammations, swellings, to severe injuries, bleeding, macerations, lessions, exposed muscles and bones, necroses etc. the lighter disorders can come and go unnoticed, or they can resolve in case of corrective actions in the husbandry. However, most of them have a worsening tenency and get worse with time. Pain and inability to grasp efficiently causes immense stress and can be lethal not only based on heavy infections and injuries, but at any severity level due to chameleons being very sensitive organisms prone to stress.
The known reasons for sole issues in captivity are as follows:
Too moist environment: the practice to sprat/mist the cages thoroughly makes sometimes the branches too moist. The moisture can not escape and gets stuck between the sole and the branch, especially when using moss or artificially moss covered vines and sticks. Especially savannah species are very sensitive to it. The permanent moisture macerates the soles and causes their susceptibility to airborn fungi and bacteria, causing bad sole damage. Solution: rather than misting use fogging; if you mist, leave the branches dry and never soak the moss or lichens on branches with water! Always leave some part of the cage not misted.
Water sticking between soles and water-resistant surface, especially during night: artificial vines, wires, plastic plants, plastic vines, plastic tubes... all these materials do not soak moisture and if the water gets between the sole and the surface and the chameleon stays with it sleeping whole night, it causes bad sole damage. The same applies to wooden sticks or branches which are treated with dyes and warnished or lacquered. It destroys the qualities of the wood and leaves the surface water resistant. Solution: do not use such materials!
Chemicals on the branches: despite of warnings and recommendations in the media, not to treat the branches for chameleons by any disinfectants, some people do. Thge woon soaks these chemicals in and once the surface becomes wet, it is expelled into the water which comes in touch with the sole. The bleaches or salts or even disifectants and disinsectants damage the soles. (https://www.chameleons.info/l/how-to-treat-natural-branches-before-putting-them-into-the-cage/) Solution: do not clean the branches with any chemicals
Toxic plants in cage: People equip ignorantly or deliberately the cages with toxic plants and the intoxication leads then to problems and death of the animals. Because the intoxications will be mild, the suffering can stay hidden same as its root cause and the death is hard to link with it, especialy as no toxicity tests are done in the rare occassions of necropsies. Solution: it is imperative not to use toxic plants, not only for preventing the chameleons to get intoxicated by munching on leaves or by feeders eating toxic plants and being then digested by the chameleons, but also to prevent contact intoxications by the toxic plants. Use the guidelines on plants here for guidance: (https://www.chameleons.info/en/various/). Beware of the high risk in the case of the widely available Hedera helix and Ficus pumila and their relatives. (https://www.chameleons.info/l/safe-and-unsafe-plants/)
Plant sap and resin contamination: plants producing saps on the basis of latex (eg. Ficus, Spurges etc) or sap of deciduous trees or resin producing conifers are causing contamination of either mechanical nature (the resins and saps are usually sticky and harden to become sturdy and preventing shedding) or chemical - they are toxic. They can also destroy the skin and pen the gate for fungi and bacteria... Some plants are inert but get toxuc when removed bark - eg. The Willow Tree (Salix sp.) is OK to be used with bark but if bark is removed, skin irritations can happen. Solution: no conifers, no plants producing toxic or sticky sap.
Mechanical damage of soles: Chameleons often tolerate sharp big thorns, eg. from Acacia trees. Small sharp objects such as small thorns and trichomes or microscopic fibres (like those of bamboo) or oxalates cause injuries and microscopic injuries opening gate for bacterial and fungal infections.
Chemical pollution of the soles from metals: sometimes, bare metals are used as mesh or main material, from which the cage is made the teperatures and humidities required for chameleon husbandry deteriorate the metals and they exspell some oxides (of Iron, Copper, Zinc) which can cause harm to the soles of chameleons. Solution: no bare metals in the cage.
Other common disorders of the terminal part of the extremities (out of scope of this text) include:
- Mechanical injuries, bites:
Chameleons can suffer various in juries of any origin. to name some are bites from cohabited chameleons, especially when raising the young, which can misidentify a tail or a piece of extremity hidden behind the branch as food or can bite due aggression. Cats, dogs, parrots, racoons, rats and mice have been also reported to cause bites, even through the mesh of the cages, especially if kept outdoors.
Solution: Prevent any contact with potential ebemies, including seemingly calm and cats and other small predators.
- Abscesses:
Abscesses are caused by external foreign bodies such as splinters, thorns, sharp objects etc., chameleons can develop swellings on terminal parts of their extremities, which are usually rather localized but can extend to part or whole foot or reach to armpit or groin.
Solution: Prevent any contact with sharp objects and in case of incident, seek a VET intervention, as the treatment might need to include surgery and usage of prescribed medicaments such as antibiotics.
- Swellings/Inflammations of nail bases:
Bases of nails get often swollen in captivity. Besides unspecific causes, the main regularly seen one is: chameleon climbing on mesh, the nail gets stuck and is teared or luxated by the weight of the animal. The consequent swelling or infection can get solved by itself, but sometimes loss of nails or even sepsis is the consequence.
Solution: Equip the cage with enough living plants and climbing branches to prevent their moving on mesh. In case of incident, seek a VET intervention, as the treatment might need to include surgery and usage of prescribed medicaments such as antibiotics.
- Swellings of joints:
Swellings of joints, especially of metatarsus and metacarpus (usually unilateral but can be bilateral) are often caused by renal insufficiency or failure and consequent gout, where sharp crystals of the salts of uric acid aggregate around joints and cause a very painful chemical and mechanical injury followed by inflammation and swelling. They are result of disease but most frequently they are the direct consequence of wrong husbandry, especially wrong feeding, supplementation and hydration.
Solution: Prevent this situation to high extent by perfect husbandry and in case of developing disease, seek a VET intervention, which may include application of analgesics, purinol and antibiotics besides of the husbandry changes. - Immobile/lame hindfeet:
Very often, captive chameleons are reported to be unable to use their hindlegs. After usually few weeks suffering, they usually die. The reason is renal failure caaused by chronic wrong husbandry parameters, especially feeding adult roaches and food too high in Phosphorus, not compensated enough with balancing Calcium intake. The kidneys are prone to destruction by excessive Phosphorus and while recognising their inability to deliver their function, they tend to compensate it with growth, get hypertrophied and swollen. Often, they grow in size to double to quadruple of the norm. Situated in the pelvic region of the body cavity directly under the vertebral column, the hypertrophies kidneys squeeze the nerves innervating the hind-legs and tail and cause their lameness.
Solution: Once the disorder is so far developed that hind-legs become non-functioning, the pathological changes are usually irreversible and the expectation of successful treatment is close to zero; it is only at discretion of a specialised competent VET. The only correct way is perfect husbandry. - Swellings of terminal parts of extremities as result of constriction by stuck shed:
A quite rare condition caused usually by wrong supplementation and hydration, when pieces of skin are not shed properly, roll together and aggregate from two or more sheddings. Especially in young growing specimen, the ring of unshed skin around growing mass of the extremity causes constriction of the vessels and if untreated, it can lead to extreme swelling, necrosis of the whole effected part of leg, sepsis and death.
Solution: Proper hydration and supplementation as preventive measures and detailed inspection of all body after shedding.
Note: While the first two above mentioned disorders can be frequently found both in wild (including feral) as well as captive chameleons, the last three have never beed reported from a wild living animal so far and are exclusive but very frequent disorder caused by wrong captive conditions.
TREATMENT
The treatment of any plantar issues is very problematic, as the chameleon uses these anatomical structures permanently, 24/7. It is very hard to immobilise the feet and any treatment brings a heavy discomfort and stress to the animal.
The treatment of not severe cases icludes disinfection of the area and removal of lesions or old skin, dirt etc. e.g. by alcohol, iodine solution or betadine.
The treatment of severe cases includes surgeries, applications of antibiotics etc is to be done by a competent specialised VET only.
PREVENTION
Due to hardship in treating any plantar disorder, it is adviseable do whatever it takes in captivity, not to harm the soles of chameleon feet by any means.
Prophylactic inspections: Inspect chameleon soles regularly and act when something is wrong!
Use safe procedures: Fog better than mist, if mist, then moderately!
Prevent problems: always have husbandry parameters at ideal levels, key areas are proper caging and equipment, lighting, feeding, supplementation, hydration...
Use safe materials: Use natural braches with bark, untreated chemically; never use conifers; sap containing plants; toxic plants; oxalates rich plants and plants with sharp fibres; never use inert materials and plastics and toxic substances incl. bare metals as a surface for chameleons to climb and sit on!
Use Common Sense, Science and Valid Experience...