Boa and Python

Steven D. Garner, DVM, DABVP Diplomate
American Board of Veterinary Practitioners
Chief of Staff, Safari Veterinary Care Centers

Boa Constrictor and Python Care

Boa constrictors and pythons are found in the rain forest of Central and South America. They are non-poisonous snakes that kill their prey by coiling around them and squeezing resulting in crushing and suffocation.

Selecting your snake: Always deal with reputable dealers and high quality pet stores. Avoid purchase from mail order reptile outlets. Shipping is often stressful and may result in onset of disease and or death. When possible, captive-bred animals should always be selected for purchase. They tend to be healthier, better adjusted and make better pets than wild caught individuals. The seller should willingly provide information on how often the snake has been eating, when it last ate and what food items it prefers. Observe the snake for attitude and response to handling. A docile snake should move forward and flick it’s tongue. A fast moving short flick is generally associated with curiosity, where a long, slow flick with very little up/down movement is may indicate a defensive attitude. Curling into a strike position and hissing demonstrate a defensive attitude. Most snakes will tame with careful handling. Be careful, bites can be dangerous and severe infections can result. Any new snake should be quarantined for 2 months and monitored for parasites and disease before introducing it into an exhisting reptile collection.

Signs of Disease:

  • Pale mucous membranes (lining of the mouth)
  • Mucous or white discharge in the mouth
  • lumps on body
  • retained dry skin
  • thin appearance with prominent spine
  • Loss of appetite
  • check for external parasites i.e. mites and ticks

Size/Growth: Neonates (newborns) are 12 to 24 inches and grow rapidly reaching 3-5 feet in one year and 4-7 feet by the second year. Adult boas range from 4-10 feet, with 15 feet possible and pythons can reach lengths in excess of 20 feet! Growth is directly related to diet and housing conditions. Diet can be used to control growth. The more frequently the snake is fed, the faster it will grow. Care must be taken in that excessive feeding of a confined snake can lead to obesity and the associated health problems. Many cities, subdivisions, and counties have laws regulating the ownership of reptiles that exceed certain lengths. Investigate these laws before purchasing a reptile. It can save a lot of frustration down the road.

Sex Determination: The male snake has a pair of copulatory organs called a hemipenes which is inverted in to the base of the tail. The female has a shallow pouch instead of a hemipenes. Both male and female snakes can have spurs located to either side of the vent (rectal opening). Generally, the male has the larger spurs but this can vary among different species of snakes. The sex can be determined by popping and probing.
Popping– manual eversion of the hemipenes in a neonate snake by applying gentle pressure with the thumb in a rolling motion from tail tip to the vent. The hemipenes, if present, should evert out of the opening of the vent. Too much pressure can injure the snake.
Probing– a metal probe is slipped through the vent to check for the presence of a hemipenes. In general, a female will probe from 2 to 4 scales deep where as the male will probe 7 or more scales in depth. Improper probing can injure a snake, so this should only be performed by those experienced in the technique.

Feeding: Newborns should be fed every 5 days. Start on pinkies, and work up from there. As the snake increases in size, feeding can be cut back to every 10 days. Your pet will be much healthier if fed a reasonable meal weekly than if gorged every two weeks. Prey items should be approximately the same diameter as the snake (the widest part of the body). A live mouse or rat can inflict severe, even fatal, damage to a snake. ALL prey should be killed or at least stunned. This can be accomplished by several methods. To humanely incapacitate a rat, place a stick behind the head and pull up on the tail to break the neck. Frozen prey kept on hand when needed, is usually cheaper than live. In addition, processed products, such as “snake sausage”, are available for feeding.

Housing/Temperature: A small tank minimum 20 gallons, is initially adequate for neonates, however, this will be quickly outgrown. A cage approximately 3/4 square foot per foot of snake is best. Shelves can be used to increase floor space and allow somewhere to “go” when active. A shelf also allows a warmer basking site, while forming a cooler area underneath. A reptile has the same body temperature as its surroundings; it simply moves to a warmer area to heat up and a colder spot to cool down. Temperature should be kept around 85°F daytime and 80°F at night. A basking site in the range of 90-95°F is also needed. Heat can be supplied from heating pads, heat lamps, ceramic heaters and by heating the room to an overall warm temperature. The reptile should never be allowed direct contact with the heat source, severe burns may occur. Hot rocks should not be used. These frequently malfunction, causing severe thermal burns to the skin of the snake. Always monitor temperature closely with thermometers at both the top and the bottom of the cage. The temperature can vary 10-15°F from the top to the bottom of the cage. Food refusal, regurgitation of prey, slow digestion, reduced resistance to disease and respiratory infections are common complications in snakes kept at too low a temperature.
The cage should contain a hiding place, a water bowl big enough for the snake to soak in and rough rocks to rub on while shedding. A hiding place is important, especially in shy species such as Ball Pythons. Constant exposure in shy species can result in stress, leading to failure to eat and disease. Many snakes prefer to eat in private. Keeping the cage clean is important. Waste material and moisture are ideal places for disease causing bacteria to grow. Cedar, bark chips or sand are difficult to clean and may hide parasites such as mites and ticks. Astroturf works very well as a floor cover. It is attractive and easy to keep clean. Plain paper also works well and is inexpensive. Remember, the easier the cage is to clean, the cleaner you will keep it. Develop and follow a cleaning schedule. Soiled substrate should be removed immediately. Clean the water container and provide fresh water daily. Clean the entire enclosure weekly. A dilute solution of bleach (1 part bleach to 20 parts water) makes a good cleaning solution. Rinse all surfaces well to remove all traces of the bleach to prevent irritation to the snake’s skin, eyes and respiratory tract. Coal tar and phenol products, like Lysol and Pinesol, are toxic. Do not use them. A full spectrum light source is recommended to light the cage during the day. It should shine directly into the cage, not through glass or Plexiglas, which can block the beneficial wavelengths of light.

Shedding (Ecdysis): As a snake grows, it generates new skin under the old. Periodically, the snake will shed this old skin. The snake removes the old skin by crawling between and rubbing against rough objects. Normally, the skin will shed in one piece beginning at the nose and continuing to the tail. Patchy shed (dysecdysis) can be an indication of a lack of proper cage furniture to rub against, low cage humidity, malnutrition, dehydration or an indication of an underlying disease condition. The faster a snake is growing the more often it will shed. An early indication that a snake is preparing to shed is the spectacles (specialized transparent scales which cover the eyes) become cloudy or opaque and the skin takes on an overall dull appearance. Do not handle or feed the snake during this time. The snake may be more aggressive while shedding and handling can disrupt the fragile procedure of shedding causing a patchy or abnormal shed. Unshed skin can be removed by soaking in water and then gently pulling it off. Retained spectacles are much more difficult to remove and if done incorrectly can result in damage to the eye. A veterinarian familiar with reptiles should perform this procedure. Other skin problems include: trauma, burns from heating pads and hot rocks, parasites, abscess, bacterial/fungal infections and tumors. Red spots (blood spots) on the skin are serious and are often an indication of internal infection.

Disease: Reptiles can hide signs of disease for weeks, often becoming very ill before any abnormalities are seen by the owner. New specimens should be quarantined a minimum of two months so that they can be evaluated for parasites and disease before placement in an existing collection. Refusal of food, open mouth breathing, bubbles from the mouth, abnormal stools and any other abnormalities are reasons to seek the advice of a veterinarian. “Normal” stools will be fairly firm and brown, to dark green in color. Urine is often passed at the same time as the stool and consists of two parts, a solid chalky portion, which is uric acid and a liquid portion, which is water and other wastes. The more commonly seen disease presentations are discussed below.

Skin parasites: Ticks and mites feed on the blood of the snake and can cause severe blood loss and can spread bacteria that can cause severe infections. The mites appear as small black to red spots (the size of a grain of pepper), attached or moving on the skin. Mites attach to the skin under the jaw (gular fold) and around the eyes. One may see dead mites in the water after soaking the snake. Please refer to Skin Parasites of Reptiles, by Steven D. Garner, DVM, DABVP Diplomate, for more detailed information.

Mouth rot (stomatitis) is caused by bacterial infection of the mouth. Presenting signs include, drooling/bubbling around mouth, open mouth breathing, refusal of food, nasal discharge and thick mucous to white caseous discharge in the mouth. Stomatitis is best treated when identified early. Treatment often involves a combination of oral flushing, antibiotic therapy and force-feeding. In severe cases, antibiotic therapy may be needed for weeks to months; therefore, antibiotic selection should be based on the results of culture of the bacteria and sensitivity testing. In severe cases, the snake may inhale pieces of the infected material, resulting in spread of infection to the lungs.

Respiratory tract infections can result from bacterial, viral, fungal and parasitic causes, as well as aspiration of foreign material and inhalation of caustic fumes. Poor hygiene, chronic low temperature and humidity too high or too low (normal 50%-70%) predispose a snake to infections. Snake mites can carry infectious organisms from snake to snake, such as the bacteria, Aeromonas, a common cause of pneumonia. Clinical signs are often inapparent until the infection has advanced to a serious state. Clinical signs of increased respiratory rate, exaggerated respiratory movements, open mouth breathing and bubbling from mouth are signs of pneumonia. Although nasal discharge may be present, it is a sign of disease in the sinus or mouth, not of pneumonia. In severe cases, prognosis is poor to grave. Treatment is aggressive and should be based on the overall condition of the snake, determined by physical examination, blood tests to evaluate cell counts and internal organ function, culture for infective organisms and in some cases, radiographs.

Food refusal (anorexia) is a sign of disease, not a disease in itself. Refusal of food may be associated with stress, cool environmental temperature, parasites, infections, intestinal impaction or foreign body. Offering prey of a different size or type from which the snake is accustomed, may result in food refusal. Traumatic experiences during feeding (rat bites), may result in future food refusal. Stomatitis and other diseases often result in food refusal. Veterinary evaluation should be sought in cases of prolonged anorexia.

Regurgitation/Vomiting may occur with mouth infections, improper temperature, improper environment (esp. lack of privacy or adequate hide spot), feeding spoiled food items, parasites or handling too soon after feeding.

Trauma, such as bites from prey and thermal burns are common. Treatment is based on severity of injury and may involve antibacterial soaks, topical creams and antibiotics in severe injuries. Feeding dead or stunned prey and restricting direct exposure to hot rocks and other heat sources best prevents these conditions.

Salmonella is a bacterial organism carried by many reptiles. The organism can cause blood, respiratory, intestinal disease or may cause no disease at all. The bacteria can cause severe disease in humans. Please refer to Salmonellosis, by Steven D. Garner, DVM, DABVP Diplomate, for more detailed information.