Snakes are elongated, legless animals with dry, scale-covered skin. Their skin is unusually elastic, which allows it to stretch when large prey items are swallowed. Snakes are rather unique because of these features and because they lack moveable eyelids and external ear openings. Snakes may be only a few inches to several yards long.

Snakes inhabit a wide variety of ecologic habitats: land, trees, underground, fresh water, and salt water. They are found on every continent except Antarctica . No native snakes are found on the islands of Hawaii , Iceland , New Zealand and Ireland .

Selecting a Pet Snake

Some snakes are rare, endangered and protected by law. These snakes may only be kept by zoos and legitimate herpetologists with the appropriate permits. This is also the case with venomous snakes, which should not, under any circumstances, be kept by the average hobbyist.

The most common snakes kept by enthusiasts are the many and varied constrictor species (boas, pythons, rat and milk snakes, etc.), and the racer, gopher and garter species. The husbandry and dietary requirements for these types of snakes vary considerably. Furthermore, some of the same species (notably the boa constrictors and pythons) reach very large sizes in captivity, and their considerable space requirements must be anticipated.

Usually, an individual eager to own a snake already has a species preference in mind because of some familiarity with it (friend owns a snake of the same species, etc.) or because of an inexplicable attraction to a species' physical appearance, size, activity or habits. Before you acquire a snake, you should carefully consider the following recommendations:

· Research the major husbandry requirements of the snake and determine whether or not you can successfully meet them now and in the future. Husbandry requirements include dietary, environmental (living space, temperature, humidity, lighting, etc.) and sanitation considerations.

· Research the temperament of the species. If you intend to enjoy your snake primarily by observing it within its enclosure and rarely by handling it, this becomes a less important consideration. If you intend to regularly handle the snake, however, you must be able to do so with minimal stress and injury to both the snake and yourself.

· Snake temperaments vary among species and among individuals of the same species. Certain snake species almost always retain a gentle, docile nature when they are raised from infancy (boa constrictors). In fact, a healthy young boa constrictor makes the most suitable pet among the tropical snake species available. Other species (the larger pythons) are unpredictable and tend to be quite pugnacious as they mature, whether or not they are handled frequently. Reticulated and Burmese pythons are especially unpredictable when they are anticipating being fed. Snakes of these types, especially those handled infrequently, become conditioned to associating feeding with human contact and often cannot distinguish the difference between these 2 situations. The small Ball python has the most predictable and even temperament of all the python species.

· Some species (anacondas) rarely develop temperaments suitable for captivity. Wild-caught adults of all species generally make unsuitable pets because they resist taming. One notable exception to this is the California Rosy boa. Even when obtained as an adult, they usually have a very shy, docile nature.

· Select a snake that can feed without difficulty and one that is eating regularly.

· Select a snake that appears healthy in all respects. Avoid choosing an unthrifty-looking snake out of sympathy with the idea that you can "nurse" the snake back to health. Many of these snakes have suffered irreparable internal damage and cannot be rehabilitated.

· Avoid selecting a snake belonging to a species that is notoriously difficult to keep in captivity, requires difficult or elaborate environmental setups, or spends most of its time hiding or burrowed underground.

Housing

As a general rule, snakes require relatively little space because of their limited and non-exertional activity. Generally speaking, the size of the enclosure should allow inclusion of certain required items and still allow the snake adequate space to stretch out and move about. Snakes will use 12-14 hours of darkness each day, with a gradual increase in the number of hours of light in the spring and a gradual decrease in the fall and winter months.

Water

Water should be provided at all times. Most snakes drink infrequently but use a suitably sized container for immersing themselves and soaking. Another advantage for including a relatively large water container is that water evaporation contributes to the relative humidity of the enclosure. This is especially true if the enclosure is glass or plexiglass-lined. The water container should be roomy enough so that it cannot be easily overturned.

Water containers must be thoroughly and regularly cleaned. Failure to do so encourages bacterial proliferation. Snakes drinking of and soaking in this water soon become ill. Use Roccal-D (Winthrop Veterinary, NY , NY 10016 ) to disinfect the snake's enclosure and furnishings at least once every 2-4 weeks.

Feeding

Before specific feeding recommendations are made, it is very important to make several points and cautions regarding the feeding of captive snakes. The most respected herpetologists and experienced snake hobbyists all agree that captive snakes should be fed dead or incapacitated prey whenever possible. This is because such prey cannot injure the feeding snake. Providing killed prey that has been frozen is convenient and economical for the hobbyist. Snakes may be induced to eat thawed, frozen prey animals by clipping hair from the coat of a live rat and rolling the proposed food in it just before feeding.

Though freezing, thawing and subsequent feeding of whole prey animals is a common practice among hobbyists and herpetologists, some experts believe that such food sources should be "gutted" (eviscerated) before they are frozen. This greatly reduces the possibility of generalized bacterial contamination of the carcass. To replace those nutrients within the viscera that would otherwise be lost, the hobbyist can place a gelatin capsule filled with a vitamin/mineral/amino acid supplement (Nekton-Rep) into the body cavity before feeding the thawed prey animal to the snake.

Live rodents can be placed in a paper bag, which is then swiftly slammed down on a countertop to stun the rodent inside. If such an incapacitated animal is offered to a snake that is generally accustomed to receiving its food in this fashion and the snakes refuses it, the prey animal can be killed and frozen, and offered at a later time.

If it is not possible to offer anything other than live and fully conscious prey for a snake to successfully feed, the encounter must be carefully supervised. If a snake shows no interest in feeding within 10-15 minutes after the prey has been introduced, the prey should be removed and all of the possible reasons for the snake's lack of interest in feeding should be investigated. If other similar attempts to feed the snake within the next 1-2 weeks are equally unsuccessful, veterinary help should be sought at once.

Snakes acquire a large number of infectious agents from the food they consume, especially because of the snake's habit of feeding on whole prey items. It is not practical or possible to ensure that all prey animals are absolutely free of disease-causing agents. However, prey animals that are to be fed to captive snakes should appear healthy and come from a reliable source.

Extreme caution should be exercised when feeding snakes. This is especially important if a given snake is expected to be hungry and if human-snake interaction is limited to feeding times. An overzealous and hungry snake is very likely to strike at a person immediately after the enclosure is opened and as the prey item is introduced. Large snakes can be especially treacherous and dangerous at these times because of their ability to overcome and overpower their keepers. Hobbyists and even a few expert herpetologists have been seriously injured or even killed at such times.

Great caution must also be exercised when feeding more than one snake within an enclosure. Serious problems result when 2 snakes choose to prey on the same food item. If one snake attaches to the front of the mouse and another attacks at the tail end of the same mouse, neither snake will surrender its hold. Both snakes will continue to feed and eventually one will consume the other!

The most common cause for failure of a snake to voluntarily feed is inadequate environmental temperatures between 75 and 85 degrees Fahrenheit for normal activity and optimum digestive capacity. Subnormal temperatures lead to sluggishness and incomplete digestion. The food literally spoils inside the snake, producing serious illness, an early sign of which is vomiting.

The next most common cause for captive snakes' refusing to feed is lack of adequate visual security. Many snakes require privacy while they feed. A hiding box or a natural bark or rock retreat may be necessary. Sometimes placing the reluctant snake in a roomy burlap bag along with a dead or incapacitated prey item provides the security the snake requires to feed. Strategic placement of silk artificial plants may also help provide additional visual security.

There may be one particular area of the enclosure in which the snake feels more secure. The food should be consistently placed there to encourage feeding. It is important to note that the presence of spectators often discourages nervous snakes from feeding. The enclosure should be covered in these cases and the snake's activity discreetly monitored.

It is extremely important for you to understand the natural history of the anorectic snake being kept in captivity. Reluctance or refusal to feed often is the result of some omission or mistake in husbandry. Burrowing species require sand or fine gravel in which to bury themselves. The snake can often be induced to strike at prey by gently dragging the prey item across the sand. Tree-dwelling species require branches within their enclosure. Some of these snakes may be encouraged to feed by hanging the food in the fork of a branch rather than placing it on the floor of the enclosure. If these specific husbandry requirements are not provided, certain snakes may not feed.

Offering incorrect prey items nearly always causes a captive snake to refuse to eat. One should offer the prey items that the snake would feed on in the wild or a similar more "domestic" food that is more available.

Following is a list of additional suggestions if a snake refuses to feed:

· Try feeding nervous snakes that share an enclosure with other snakes in an environment separate from them. Often, the movement of other snakes in the same enclosure induces anorexia in nervous snakes.

· Moving a snake to a new or different enclosure may stimulate feeding.

· Reduce handling of especially nervous or newly acquired snakes to encourage feeding.

· Rubbing the food item over the sensitive areas of the snake's head (the nostrils and the areas surrounding the mouth) or gently hitting the snake with the prey may antagonize it to strike at the food.

· Offer live prey to snakes that have been consistently offered dead or incapacitated live prey (with close supervision). Certain aggressive snakes and snakes with an impaired sense of smell may require live prey to successfully feed.

· For snakes that ordinarily eat live prey, try feeding dead or incapacitated live prey items. Often, the erratic motions of a rodent running around an enclosure can cause a snake to refuse to feed.

· Try feeding a smaller prey item. A snake that has been recently injured by a particularly large and aggressive prey animal may be reluctant to feed.

· Cater as much as possible to the individual preferences of an anorectic snake. If a snake refuses mice, try small rats, gerbils, hamsters, rabbits or even chicks. Some snakes can be very finicky.

If all of the above have been considered and attempted without success, take your snake to a

Veterinarian experienced with snakes. The veterinarian will collect a detailed history and conduct a thorough physical examination. It may be necessary to collect a blood sample to more thoroughly evaluate the patient. Take along a fecal (stool) sample from the snake so the veterinarian can also check for intestinal parasites.

A veterinarian may pass a flexible tube into the stomach and force-feed the anorectic snake at this time. This provides some nutrients while the medical evaluation is in progress. Some anorectic snakes begin to voluntarily feed after such a feeding. This can be easily learned if periodic at-home force-feedings are anticipated. Strained meat baby foods with added Nekton-Rep or pureed dog food are recommended and easily pass through most stomach tubes. Larger snakes require relatively larger volumes of food; pureed dog food is a more practical food in these situations. Low-fat dog food is preferable.

Regurgitation

Regurgitation of food may result from handling a snake too soon after it has fed. Regurgitated food is undigested and relatively odorless. Another common cause of regurgitation is inadequate and incomplete digestion caused by relatively cool environmental temperatures. In these cases, the regurgitated food appears digested and is malodorous. If it is not possible to raise the temperature of the enclosure, a focal source of heat (hot rock, heating pad or pads) on which the snake can rest is a necessity to ensure adequate and complete digestion.

Other causes of regurgitation include stress in easily excitable species, parasitism, intestinal obstruction and serious internal disease. An experienced veterinarian should be consulted if the cause for regurgitation is not readily determined.

Trauma

· Burns: Snakes commonly sustain serious burns when they contact unprotected or malfunctioning heat lamps or other heat sources (including hot rocks). Interestingly, snakes tend not to move away from the heat source inflicting the injury. This makes the wound considerably more serious. Medical treatment (including injectable antibiotics and periodic wound dressings) is required in these cases. Surgery may be necessary to minimize the disfiguring effects of such injuries.

These injuries are easily avoidable. Periodically check all heating appliances to make certain they are functioning properly and that they are "snake proof".

· Rat/Mouse Attack: Sometimes a live mouse or rat turns the tables on a snake and injures the snake while fighting for its life (the dinner becomes the diner). Veterinary attention should be sought for serious bite wounds.

· Rostral Abrasions: One of the unfortunate consequences of captivity is injury to the captive animal from repeated attempts to escape. Snakes tend to push and rub their noses against the walls of their enclosure as they move about in search of a means to escape. This constant trauma initially damages the scales and skin of the nose (rostrum). If the trauma continues, deep ulceration of the rostrum with subsequent deformity may result. Rostral abrasions are equally likely with enclosures made of glass or wire mesh.

Prevention of this problem is difficult, but adequate visual security (hiding places) and other additions to the enclosure (artificial plants, branches, etc.) help minimize it. Furthermore, a visual barrier of dark paint or plastic film placed on or along the lower 3-4 inches of the enclosure's walls often inhibits pacing and rubbing.

Constipation

Constipation is a common problem among captive snakes. Causes include sub-optimal environmental temperature, illness, dehydration, injuries, parasitism and cloacoliths.

Constipated snakes should be allowed to soak in very warm (not scalding hot) water for 20-30 minutes daily for 1-2 days. This often results in defecation and/or urination. If this conservative measure is not successful, veterinary help should be sought at once.

Cloacoliths

Dehydration of captive snakes (especially if long-standing) may result in drying out of urinary excretions. When this occurs, uric acid "stones" tend to form within the cloaca ("cloacoliths"). Their presence in this location prevents expulsion of urinary waste and feces (constipation), which creates serious illness. Dehydration is a sign of disease and not a disease in itself, so it becomes the veterinarian's task to determine the underlying problem that caused the dehydration. Cloacoliths can usually be manually expelled with patience and the help of mineral oil enemas. This procedure should only be attempted by an experienced veterinarian.

Prolapses

A prolapse occurs when an organ inverts itself inside out and protrudes through the usual external opening of that organ. Prolapses of the cloaca and reproductive organs are not uncommon among captive snakes. Often the cause cannot be determined. Prolapses can be precipitated by straining during egg-laying or straining related to uric acid stones. Parasitic infections or other intestinal disease may also result in these cases to treat the prolapse and determine the underlying cause, if possible.

Abnormal Shedding

Abnormal shedding occurs when the normal sequence of events of the shedding process is somehow interrupted. This usually results in a piece-meal shed and/or retained eye caps.

Signs may be subtle or obvious and may include lethargy, anorexia, dehydration, regurgitation of incompletely digested food, redness to the skin and scales, or bleeding from the skin.

The help of an experienced veterinarian is essential in these cases. The outlook for these patients is always guarded to poor. The attending veterinarian may collect a specimen for bacterial culture and antibiotic sensitivity testing, as well as one or more blood samples to more accurately determine the extent of the disease, whether or not various internal organs are involved, and as a means of monitoring the patient's progress.

Treatment involves use of injectable antibiotics and appropriate supportive care (fluid therapy, force-feeding, injectable vitamins, etc.). Treatment must usually be relatively long-term and periodic monitoring of the patient's status is essential to a favorable outcome.

Respiratory Disease

Respiratory infections are common in snakes. They may be associated with septicemic (body-wide) illness, viral infections and mouth rot. Some respiratory illness may be the consequence of stress from poor or inadequate husbandry.

Signs include loud respirations, discharge and/or bubbling from the nostrils and/or mouth, coughing and open-mouth breathing. Treatment must be aggressive and at the direction of a veterinarian. A bacterial culture of the windpipe and subsequent antibiotic sensitivity testing should be undertaken to identify the offending bacteria and the appropriate antibiotic(s) to use. The veterinarian may also recommend collecting a blood sample to determine the extent of the disease and to see if there has been serious compromise to internal organs. Antibiotic therapy should be by injection and may need to be long-term, especially in severe and long-standing cases. Inhalation therapy (vaporization or nebulization) is frequently employed as part of treatment.

Eye Infections

Captive snakes occasionally suffer eye infections. Infections may be superficial or more extensive, involving the entire eye. Superficial infections may result from mild injury to the eye. Superficial infections may also become established below a retained eye cap. Infections of this type must be recognized promptly and treated aggressively to prevent involvement of the entire eye. The retained eye cap must first be removed if at all possible. Infections involving the entire eye may result from trauma to the eye or from septicemia (body-wide infection). In the latter case, the bacteria enter the eye by way of the bloodstream.

Veterinary help is essential with these cases. Treatment involves use of topical and/or injectable antibiotics. Sometimes, drugs that help to exercise the iris (the colored portion inside the eye) are used to help prevent adhesions inside the eye.

Viral Infections

Viral infections in snakes, as a whole, are generally poorly understood. This is because viruses are extremely difficult to detect and identify. They are equally difficult or impossible to treat.

Viral infections result in tumorous skin growths in many native snake species. Other viruses can cause digestive, respiratory, and nervous system disease among snakes. An example is a recently recognized viral encephalitis affecting pythons and boa constrictors. Afflicted constrictor species exhibit a very gradual deterioration of the brain and eventually die.

Most viruses are highly contagious. Hobbyists must be aware of this and quarantine all newly acquired snakes for at least 6-8 weeks. This involves complete isolation of new snakes and careful scrutiny of them during this period for any signs of illness.

All newly acquired snakes should be thoroughly examined and evaluated by a veterinarian experienced with snakes. Blood tests may offer clues as to viral infections.

Fungal Infections

A number of fungal organisms can cause superficial and deeper infections of snakes. Most of these infections involve the skin and respiratory system. Fungal infections of the eyes are most likely to occur in snakes housed in damp, contaminated environments. Ringworm fungi that usually infect people, pets and livestock have also caused skin infections of snakes.

Snakes should be housed in scrupulously clean and dry enclosures. The flooring must be easy to clean and should not be of a material that encourages fungal (mold) growth.

Snakes exhibiting problems with their skin and/or eyes must be carefully examined by a veterinarian as soon as possible. A microbial culture and a skin biopsy may be necessary to obtain a diagnosis. Treatment of fungal diseases involves use of topical and systemic (oral and/or injectable) anti-fungal agents. Prevention of fungal diseases involves correcting underlying problems with husbandry.

Parasitic Diseases

Snakes can be hosts to a large number of parasites, representing a bewildering variety of organisms. Mites are the most common and most dangerous of the external parasites of captive snakes. These mites feed on the blood of their hosts, causing anemia (often severe with heavy infestations). Blood-feeding can also transmit viruses, at least one very serious disease-causing bacterium, and blood parasites.

The snake mite completes its life cycle on its host. The females, however, lay up to 80 eggs off the snake within the environment. This is one reason why particulate floor coverings (corn-cob material, pebbles, etc.) are not recommended. These substrates provide too many hiding places for the mites and their eggs.

Snakes that are most likely to be seriously compromised by this external parasite are those housed under crowded, unhygienic conditions. Heavily parasitized snakes are also likely to be adversely affected when they are suffering from malnutrition and/or other diseases at the same time.

Veterinarians must be consulted when these various circumstances arise. These snakes must be carefully examined and thoroughly evaluated so that underlying disease and problems with husbandry can be identified and corrected. Furthermore, the recommended treatment can often be injurious, especially to snakes suffering from debility and/or disease. The veterinarian must perform a thorough physical examination and mat recommend a blood analysis to fully evaluate the patient, the advisability of treatment, and the least harmful method of treatment for mites.

Several treatments are available for snake mites. One popular method involves suspending a No-Pest Strip (Shell) above or adjacent to the snake's enclosure for 2-5 days. One expert recommends a "dosage" of 0.2 inches of commercial strip per 10 cubic feet of enclosure. An alternative is to place a 1-inch section of a No-Pest Strip within a 35-mm film container with multiple perforations and suspend it inside the enclosure for 2-5 days. These products should be used cautiously, however. They can be especially toxic to severely ill and debilitated snakes.

Flea sprays formulated for use on dogs and cats can be applied to a small towel and the chemical can be wiped onto the skin and scales. This procedure should be repeated about 10 days later. During treatment, any particulate floor covering (gravel, crushed corncob, wood shavings, etc.) within the enclosure must be replaced by paper or towels. All water containers should be thoroughly cleaned and fumigated with 10-15% solution of formalin and hot water. After a thorough rinsing, the enclosure should be allowed to completely dry before it is reinhabited. Treated snakes should be closely monitored for several months for signs of re-infestation and mite-related disease.

Snake Tick Infestation

Ticks resemble oversized mites and occupy many of the same sites on the skin and scales of snakes as mites. They are often found just inside the mouth, nostrils, or vent. Even under conditions of captivity, ticks rarely reach the burdensome numbers reached by mites. Recently imported snakes are usually the most heavily parasitized.

Like mites, ticks feed on blood of the host snake and can cause severe, life-threatening anemia. Their blood-feeding habit enables them to transmit certain blood-borne diseases to snakes.

Manual removal of each individual tick is the most expedient treatment for tick infestations. The hobbyist must exercise great care in performing this task. Simply pulling off the tick leaves the tick's mouth-parts embedded in the skin. A small amount of alcohol applied to the exposed parts of the tick causes it to relax and facilitates removal. The treatment methods recommended for mites are also effective. Parasitized snakes usually require a minimum of 4 days' exposure to No-Pest Strips to kill ticks. Enlist the services of an experienced veterinarian for a thorough pretreatment evaluation of the snake, especially if the use of a No-Pest Strip is anticipated.

Cancer

Cancer occurs in snakes, but the number of reports is quite limited. Some of the tumors have been diagnosed on living snakes, but most were diagnosed at the time of autopsy. As with mammals, tumors of snakes can be benign or malignant and originate from any organ or tissue of the body, including blood.

Boa constrictors seem to be more often affected by cancer than other snakes commonly kept in captivity. This observation, however, may be the result of the disproportionately large number of boa constrictors kept by hobbyists because of their tremendous popularity. It is interesting to note, however, that most life-threatening malignancies that we have diagnosed in snakes have involved boa constrictors. Snake owners must be vigilant and seek prompt veterinary help when a growth or lump is detected on their snake(s)(especially if a boa constrictor is involved). "Mole-like" growths have been especially troublesome in our experience. Wounds that fail to heal despite treatment should make you equally suspicious.

Organ Failure

Failure of vital organ function may be the result of advancing age or cancer but is usually a consequence of chronic and unchecked disease among captive snakes. Disease that has gone undetected and/or untreated can have devastating and sometimes, fatal consequences. Under these circumstances, organ function is greatly compromised and the snake's usually smooth-running metabolism is threatened.

* Portions reprinted from Avian and Exotic Hospitals of L.A. and Orange Counties *