Anorexia in Snakes
Dr. Nancy Anderson
Anorexia is the loss of appetite or refusal to eat. It can be a health problem in itself or it can be a sign of underlying problems. If your snake shows other signs of illness such as weight loss, depression, abdominal swelling, vomiting, diarrhea, sores in the mouth or on the skin, wheezing, abnormal discharges or abnormal posture in addition to not eating, there is a good chance that your pet is seriously ill and you should take him to a veterinarian who is experienced in reptile care. Hematology (analysis of red and white blood cells)
Except for some female snakes just prior to egg laying and snakes undergoing planned hibernations, it is not normal for captive snakes to refuse to eat for more than one to two months. Many snakes from temperate climates tend to decrease their feeding rate in the autumn as the light cycle decreases. If your snake is healthy, you may just want to decrease feedings for the cooler months, but you should be vigilant to ensure that as the light cycle lengthens your snake's appetite returns. Many owners whose snakes significantly slow down for the winter season elect to hibernate them. When snakes are prepared correctly for hibernation, it may be preferable to keeping them active for the winter.
Snakes often go off feed temporarily prior to shedding. When their skin is grey, they cannot see very well and often appear to be irritable. Once the shed is complete, the appetite should return to normal.
Wild caught snakes that are not used to living in captivity or eating domestic prey animals often suffer from anorexia. Newly acquired snakes and shy, retiring species such as ball pythons often refuse food until they become used to their new cages and owners.
If anorexia is allowed to continue for more than a few weeks, however, it can predispose the animal to infection. Severe, possibly non-reversible liver and kidney damage can occur if anorexia is allowed to go on until the animal has lost a significant amount of weight. Anorexia is a sign that a snake does not feel secure enough in his cage to eat. This is a strong indication to improve husbandry and reduce stress.
Unless your veterinarian finds an obvious cause for anorexia on physical examination, such as mouth infection, pneumonia, or parasite infection, a detailed history is extremely important. If your snake has produced a recent stool take it with you to the veterinarian, so that it can be tested for parasites.
If your snake has not eaten for more than one to two months depending on the size and age of the snake or has lost significant body condition, further diagnostic tests are warranted. These include:
Serum chemistries (evaluates organ function)
Cytology (microscopic examination of discharges or small samples of tissue)
Specialized fecal analysis
Bacterial or fungal cultures
If husbandry problems are diagnosed and the snake appears healthy on physical examination, treatment is aimed at improving his environment and removing any intestinal parasites that may have been diagnosed on a fecal examination.
If your reptile has not eaten for awhile, he is probably dehydrated. It is important to rehydrate the snake prior to attempting to feed him. Depending on the severity of dehydration and the level of kidney and liver function, your veterinarian may select to rehydrate your snake with oral fluids given into the stomach with a feeding tube, subcutaneous fluids (under the skin), or intraperitoneal fluids (fluids given with a needle right into the abdominal cavity). In extremely severe cases, your veterinarian may want to hospitalize your snake and administer intravenous fluids.
Once your snake is rehydrated, it is important to start a series of tube feedings that are geared to prepare the intestines to digest real food again.
Concurrent treatment of any underlying medical problems, such as bacterial infections, obstructions or organ dysfunction, is crucial to the successful treatment of anorexia.
Administer fluids, food supplements and medications according to your veterinarian's instructions. Also, observe the general activity level and interest of your pet. Note the character and frequency of stools. Contact your veterinarian if you notice regurgitation. This is a sign that the medications or the feeding regime needs to be updated. In addition, do the following:
Schedule regular veterinary visits to monitor the condition.
Use a thermometer to measure the temperature gradient in the cage. Just feeling cage surfaces is not precise enough. Adjust heating devices to maintain a temperature range recommended by your veterinarian.
Make sure that your snake gets a proper light cycle. Usually 12 hours light to 12 hours of dark is recommended for tropical species and 10 hours of light and 14 hours of dark in the winter and 14 hours of light and 10 hours of darkness in the summer is recommended for temperate species that normally live in North America or Europe.
Make sure you know what your snake eats in the wild. Trying to feed a mouse to a snake that only eats eggs will not be successful. Do not buy snakes for which you can't easily obtain prey items.
Try another species of prey. If your snake won't eat mice, try a hamster or if your snake won't eat a goldfish, try a minnow.
Make sure that the size of prey is appropriate for your size snake. A good rule of thumb is that the head of the prey animal should be no larger than 3/4 the diameter and no smaller than 1/4 the diameter of the snake's head.
Offer food during the time of day that the snake would be hunting in the wild. Offer it when there are few or no people around.
Never introduce a fully functional prey animal to an anorexic snake without direct supervision. When the snake is not interested in eating the rodent, there are countless cases where rodents have attacked the snake. Many snakes have been seriously injured or killed by rodents that were supposed to be their prey.
Your snake will not eat if it is not well hydrated, so make sure that the water dish is large enough for him to soak in. Keep the water fresh and clean.
The best prevention is to buy healthy captive bred snakes that are readily feeding on their own on easy-to-obtain prey items. At home excellent husbandry will prevent most snakes from becoming anorexic.
Avoid handling snakes for at least 48 hours after a meal. Have your veterinarian test a stool sample from your snake for the most common parasites found in that species. Follow your veterinarian's instructions for administering de-wormers. In addition, make sure you clean and disinfect your snake's cage and cage furniture after all de-wormer doses. This will minimize your snake's chances of re-infecting itself from immature parasites or parasite eggs that may be in the cage.