8.1 What regular checks should I make on my caiman?
It's always a good idea to keep a close eye on your animals for signs of ill health - or anything out of the ordinary which indicates that something might be going wrong. One of the best ways of checking the health of your caiman or other crocodilian is to maintain good record of its feeding behaviour, its body size and its weight. While taking morphological measurements might not always be feasible, especially in larger animals, problems can often be diagnosed first if you are able to collect these data. When a crocodile stops feeding, it may be the prelude to something more serious.
Keep an eye on your animal's overall body condition. A loss of muscle mass around the tail and neck, and reduced volume of the abdomen can indicate anorexia or poor digestion efficiency. The belly skin should remain bright and clean at all times. Serious problems such as septicaemia can often be diagnosed from discolourations on the belly. Examine the upper and lower body surface thoroughly for physical injuries, or bacterial and fungal problems. Your caiman will probably be very keen to bite you during the examination, so take the opportunity to check inside the mouth for ulcers and exudates which may be indicative of pox virus or stomatitis (mouth rot). Other things to look out for are discussed in section 3.2. Other problems, which may display specific symptoms, as described below.
8.2.1 What kind of physical injuries can my caiman suffer from?
If you keep your caiman by itself, physical injuries should be rare as long as the enclosure is safe. A common cause of injury in a solitary crocodilian comes from smashing the head against the side of the enclosure or objects, either when trying to subdue prey, or when struggling if being restrained. As the head is mostly reinforced bone, little injury is actually inflicted to the animal. Small cuts will heal rapidly, and if teeth are lost they will be replaced eventually - crocodilians regenerate their teeth throughout life. Live prey have the potential to bite or scratch the croc and, although these injuries are rare and usually minor, it is another negative mark against the feeding of live prey to captive animals. Crocs will usually try and roll if they're restrained (e.g with a noose) which abrades skin from the dorsal scutes covering the back if the animal is on a hard surface such as concrete. While these injuries are minor, they do detract from your animal's overall appearance and can act as sites for bacterial or fungal growth.
Relatively minor injuries (e.g. corneal scar, see right) are common in crocodilians kept together. However, some fights have the potential to be very serious especially in larger animals. Fritz Huchzemeyer DVM points out that many injuries are inflicted by cagemates during feeding, usually to the head or front limbs. Deep tissue cuts should be examined by a vet and sutured if necessary. Serious injuries occur when one animal holds onto another with its jaws and bites very hard while spinning its entire body axis. Limbs, jaws and tail tips are easily twisted off during such encounters, and deep puncture wounds through flesh and bone can be inflicted with the teeth. Again, the ability of a healthy crocodile to recover from such physical trauma can be remarkable, but veterinary attention should always be sought in these cases. A missing tail tip or even an entire limb will not hinder a crocodile too much, but a damaged jaw often inhibits or prevents the animal from being able to feed correctly. Fritz Huchzemeyer DVM: "Apparently injuries to the upper jaws are tolerated quite well. You often see adult breeding crocs on farms with half the upper jaw missing and perfectly able to cope. Injuries to the mandibles [lower jaw] are different because the croc ends up with 2 loose half mandibles and really is unable to feed."
Crocodiles often fight one another by swinging the head laterally and with massive force into the opponent. This can bruise and lacerate tissue, smash teeth and splinter bone. Never underestimate how powerful these animals can be, especially when larger.
8.2.2 What kinds of disease can my caiman suffer from?
While healthy crocodilians rarely suffer from disease, they are certainly not immune. Crocodilians are particularly susceptible to stress - it affects their appetite, their resistance to disease and their overall health. Keeping stress to a minimum should be high on your list of priorities. Fritz Huchzemeyer DVM defines the following general conditions which can lead to stress:
Thermal stress - where the animal is unable to thermoregulate correctly,
Capture stress - when the animal is caught and handled, a factor which is less severe in juveniles (which may be picked up by their mothers) and more severe in older, unsocialised juveniles (where being picked up is a prelude to being eaten) and adults (which are never picked up or handled),
Social stress - arising out of competition and the inability of adults to establish a territory (e.g. enclosure too small, densities too high).
In effect, any condition which prevents the animal from being able to follow its natural behaviour will result in some form of stress. In addition, nany of the problems seen in crocodilians stem from a lack of hygiene in their enclosures. It is imperative that you maintain high standards of cleanliness in the enclosure if you want to avoid these problems.
The feet and limbs are often the sites for ulcers, swellings and abscesses either from infected bites or abrasion against materials in the enclosure. Such injuries and infections are more numerous in older, longer-term captives, and may be present anywhere on the body. Again, the chance of a bite becoming infected is much greater if your enclosure is not clean. Skin infections (bacterial and fungal), oral inflammation, and mixed bacterial infections around the vent are all indications of unhygienic conditions.
Mouth rot, or stomatitis, can also be found in crocodilians as well as other reptiles. It is usually multifactorial (e.g. stress, malnutrition, secondary infection), and thus indicates the presence of a more serious problem leading to a generalised systemic infection or a depressed immune system. Stomatitis may be triggered by unhygienic conditions in the enclosure, consistently poor diet or in some cases physical injury to the oral cavity which is then infected (e.g. by Aeromonas and Pseudomonas bacteria).
Caiman pox-virus has been recorded in Caiman crocodilus, although it does not appear to be common. The symptoms include circular, white lesions covering the scales of the upper and lower jaws, as well as the eyelids and earflaps. These may then spread to other areas of the body. Lesions form a hypertrophied epithelial layer that may eventually slough off. Of the few reports that exist on this virus, most animals seem to recover if given enough time.
8.2.3 What kind of parasites can attack my caiman?
External parasites are rarely seen in captive crocodilians outside of crocodile farms. One of the more common parasites is a nematode called Paratrichosoma which lives under the belly skin and migrates across scales in a characteristic zig-zag pattern. This parasite is normally only found in wild crocodilians, or animals infected from wild stock in crocodile farms. It does not appear to be specific to one species. Other external parasites associated with the skin may include leeches, trematodes and protozoans. Internal parasites common in the gut of wild crocodilians include ascarid round worms.
Fredric Frye DVM: "Because essentially all of my crocodilian patients have been in very long-term captivity, ectoparasitism is not a problem. Wild-caught crocodilians usually have both haematoprotozoans (mostly haemogregarines) and gastrointestinal helminths. Those that have been housed with wild-caught turtles may have transient leech infestations. However, these are rare and easily dealt with on an individual basis."
8.2.4 What are the most common dietary problems?
Problems from an incorrect diet are common in the ownership of reptiles, and crocodilians are no exception. In many cases, reptiles can be fed a poor diet for an extended period before any symptoms become apparent, and it can sometimes be difficult to persuade the owner that they're doing anything wrong.
One of the more common dietary problems is metabolic bone disease (MBD). MBD is not an infectious disease, but the fault of incorrect diet and husbandry. Diets that consist of little more than organ / visceral meat or lean meat without bone are usually lacking in calcium and high in phosphorous. A calcium to phosphorous ratio (Ca:P) of 1-1.5:1 is normally required for crocodilians. Vitamin D is also required in order for calcium to be absorbed from the gut and utilised, and can be obtained either from certain prey items or synthesised in the skin through exposure to UVB wavelengths in sunlight or artificial UV lights. If calcium is not available to the crocodile, and the Ca:P ratio becomes weighted towards excess phosphorous, the parathyroid gland will be stimulated to produce parathyroid hormone. This begins the process of extracting calcium from bone and replacing it with puffy, fibrous collagen that distorts and fractures easily. Entire limbs becomes swollen and misshapen. The jaw typically becomes very soft and pliable from decalcification, and teeth usually become translucent around the edges or even begin to fall out. In prolonged cases of low calcium levels, the lower mandible fails to lengthen giving the crocodilian a noticeable underbite. Kidney damage can eventually result, and nervous / muscular function can be impaired. Twisting of the spine is also typical especially in younger animals whose calcium requirements are higher for growth. Increasing variety in the diet, including bones, and using calcium supplements with vitamin D provided in the diet or through sunlight are ways to avoid metabolic bone disease.
As mentioned earlier in the diet section, vitamin B1 deficiency is common in diets comprised primarily of fish. Many fish, especially oily marine species, contain high levels or thiaminase which breaks down vitamin B1 (thiamine) and renders it unavailable to the crocodile. The freezing / thawing process exacerbates this problem. Symptoms of B1 deficiency include muscle tremors and twitching, and the problem can be corrected with B1 supplements, heating fish briefly to denature the enzyme, and an improvement in the diet. Another common problem with fish diets is steatitis: necrosis of fatty tissue caused by excess polyunsaturated fatty acids which begin to oxidise when the fish are not totally fresh. Vitamin E supplement (which acts as an anti-oxidant) or an improvement in the diet to include mammals and birds can address the problem.
Another common problem mentioned earlier in the diet section is gout - normally caused by an excess of protein in the diet or because the kidneys fail to function properly (e.g. if the animal is too cold). Usually, gout is seen in crocodilians being overfed because the body simply cannot deal with all the protein it is trying to assimilate. The normal breakdown product of protein metabolism is ammonia which is excreted as ammonium carbonate. Uric acid is produced in smaller quantities but if the kidneys are unable to excrete it adequately then it begins to crystallise out in various tissues. Arthritic gout normally results in uric acid deposition around joints and leads to painful paralysis. Visceral gout results from uric acid being deposited around internal organs. Low temperatures also impair uric acid excretion, so an overfed caiman that is too cool is a likely candidate for gout. Moderating the feeding regime and ensuring that temperatures are within the preferred range can prevent gout.
Hypoglycaemia has been reported in small crocodilians - low blood sugar levels - and it is normally triggered by stress and lack of food intake (e.g. if it starts to get too cold). Hypoglycaemia results in neuromuscular problems such as tremors, lack of coordination and loss of the righting reflex. Dilation of the pupils is a typical sign. Apart from trying to alleviate the stress, administration of glucose in the diet can be a temporary solution.
A general lack of eating and weight loss (anorexia) is another relatively common problem that is frequently caused by stress. Crocodilians stress very easily, often over apparently minor things like a change in their daily routine. Hatchlings frequently go off their food if they receive unusual stimuli, although stress levels in crocodilians are reduced once an animal gets used to these stimuli (e.g. being handled, enclosure cleaning, excessive noise, etc). Anorexia can also indicate that things are generally not well with your animal, and veterinary attention should be sought if the problem cannot be immediately identified. As crocodilians have a proclivity for trying to eat just about anything within their enclosure, some strange objects can be found within their stomachs. Although stones are frequently eaten under natural conditions, both to assist digestion and perhaps also to act as a ballast, other artificial objects can be less beneficial and may actually block part of the intestinal tract - a situation which will stop the animal from eating and eventually lead to death if veterinary intervention is not sought. Some believe that stress in captive crocodilians leads to increased ingestion of foreign matter in their enclosures.
8.2.5 What are the most common problems and their causes?
The majority of animals that are presented to vets probably wouldn't be there in the first place if correct husbandry procedures were always followed. The diet can be a major cause of problems, especially as there's a general perception that crocodilians can eat just about anything. This may be true, but not everything they eat is necessarily good for them over a long period of time, and a good balance must be maintained. Many injuries could also be avoided by ensuring the enclosure is safe for the inhabitant, and that there's enough space for multiple occupants to get along. Pathogenic problems are frequently associated with poor hygiene, especially in an enclosure which contains both water and land areas that require frequent cleaning.
Fredric Frye, DVM: "Infections are certainly the most common reason for seeking veterinary attention. The institutional-kept crocodilians (e.g. zoos, aquaria) are usually maintained under much better captive conditions. Once my clients are appraised of what measures are necessary, most health problems are obviated. Filth-borne infections are easily avoided by good hygiene. In cases of aggression, we remove and isolate the individuals who are expressing this aggression. Whenever possible, I try to place fighting crocodilians in other venues where they can establish new hierarchies."
If any of these problems do occur because of your husbandry practices, don't feel guilty about it, but take immediate steps to improve the situation. Often we all have to learn things the hard way, but one reminder should be enough.
8.3 Can I treat injuries and disease at home?
If the condition is relatively minor, there is usually no reason to stress the animal by taking it to the vet. Topical administration of disinfectants (e.g. povidone-iodine, chlorohexadine) to prevent infection of small cuts and other wounds is relatively straightforward. The animal should preferably be kept out of water for at least 30 to 60 minutes so the administered substance has a chance to be effective. Regular treatment of wounds for several days will aid the healing process. Treating a small crocodile in this manner is easy, but larger animals may require additional assistance to treat safely. If you've never done this before, take your animal to the vet and listen to his or her advice. Simple procedures can easily be taught.
Most vets are of the opinion that the best way of treating these problems is to ensure they don't occur in the first place. Maintain excellent hygiene, feed a suitable and varied diet, and don't keep incompatible animals together.
Obviously, if a health problem is too serious to be treated by the owner, then you should seek immediate veterinary attention. Even in the absence of obvious illness, most vets like to see their clients at least once a year for a general check up unless there is a legal requirement for a more regular check (see below). Whilst you might consider this to be an unnecessary expense, it can save you a lot of money in the long run (or save your animal's life) if any problems are detected before they become serious. Keeping a crocodilian is an expensive investment in time, equipment and the animal - regular checks help to protect this investment. Procedures such as blood panel checks and x-rays can also be helpful in assessing the animal's overall health.
Fredric Frye, DVM: "Most individual owners (with a few notable exceptions) wait until they perceive a health problem and then call for help. I do, however, have three individual owners who possess annually renewed permits who must, by statute, have their animals examined twice yearly. Accordingly, these crocodilians (alligators and caimans) are maintained in superb health."
8.4.2 What information or samples will the vet require?
You can considerably assist your vet's diagnosis and early treatment of any problems if you can provide details on your animal's recent and long-term history. It's an excellent idea to keep a record of every feeding - the time of feeding, and everything the animal ate. If possible, take periodic growth and weight measurements and record any physical or behaviour changes you might have noticed. Health problems can normally be seen well in advance if you monitor these variables. Also, be sure to tell your vet if you changed procedures or recently used a new cleaning agent for example. Vets also need to know if you've administered any of your own medications to the animal - e.g. what you used, the dose you used, and how you administered it. Before a visit, try and obtain a faecal sample. This isn't always easy with crocodilians as they often defaecate in water. You need to collect the stool sample, rather than the watery urine and milky white urates. The stool can often be very soft and difficult to collect - a croc's digestive system is very thorough. The faecal sample will enable the vet to look for parasites and bacteria, and check factors such as digestion efficiency.
8.4.3 What if my animal is too large and aggressive to take to the vet?
Sitting in a veterinary hospital waiting room with a 12 foot crocodile is hardly feasible, so you need to consider other options when your animal grows very large. Most vets who are qualified to deal with large crocodilians will visit your premises for a suitable fee, although they'll typically require as much information as possible from you about the problem first. In serious cases, the crocodile may have to be sedated and transported to the surgery for treatment, but this is entirely up to your vet - many refuse to deal with very large animals because they simply don't have the facilities for it. It's impossible to predict the requirements of every vet in all situations, but as the owner of an animal that has the potential to grow very large and become highly aggressive, you must consider these potential problems well in advance so you know what action to take.
8.5 Are there any zoonoses (diseases) I can catch from my caiman?
Crocodilians normally carry a diverse variety of bacteria in their mouths and on their teeth, and infections resulting from penetrative bites are quite common. These should be dealt with using an appropriate antiseptic (e.g. povidone-iodine, cholorohexadine) unless the physical injury requires professional medical attention.
The only other serious problem likely to be encountered is Salmonella, but I do not know of any recorded cases of a person catching Salmonella from a crocodilian. There are a number of different Salmonella bacteria which are frequently found in the guts of reptile species, and crocodilians often carry at least one variety in their intestinal tract. These bacteria are shed with the faeces, so in an aquatic environment the entire enclosure and water could potentially harbour these organisms. These bacteria do not normally affect a healthy crocodile, but animals in poor health can suffer from an over-proliferation of Salmonella that can lead to serious problems. Most healthy humans are quite tolerant of Salmonella, but immuno-compromised individuals are definitely at risk. It goes without saying that the easiest way to prevent problems with bacterial contamination from crocodilians is to practice proper hygiene - wash your hands thoroughly using anti-bacterial cleaners after handling your animal, the water or any objects within its enclosure.
8.6 Should I trim my caiman's claws?
The short answer is no, do not trim the claws of any crocodilian.
All crocodilians have a curious arrangement of claws. They have 5 toes on their front feet, and four on their back feet. However, only the inner 3 toes on each foot (front and rear) possess claws - the other toes simply terminate in a fleshy stub. When young, the claws can be a little sharp, but never enough to break your skin or cause injury whilst they are being handled. Trimming them is totally unnecessary, and you risk cutting through the living tissue or quick within the nail. As they grow, their claws become blunter, and frankly they are the least of your worries with a larger crocodilian! Crocodilians in captivity which are kept on a rough substrate will actually wear their claws down constantly as they walk around, which is quite noticeable when you compare them to the claws of a wild animal living in a freshwater pool, for example.
8.7 Where can I find a list of vets capable of treating crocodilians?
Ring your local veterinary practice or zoo and ask whether they have a reptile vet who is willing and qualified to treat crocodilians. It is a very good idea to find this out before you consider purchasing any kind of crocodilian, otherwise if the animal eventually requires veterinary attention you'll have serious problems finding anyone capable of helping you. There is a list of reptile vets who have agreed to treat crocodilians in Appendix I. This is certainly not a complete list, but it's a good starting point.