When I was in the College of Veterinary Medicine at Texas A&M University, I had a very brief “everything you need to know about chinchillas” lecture. Needless to say the professor only covered a few topics, and it was definitely not everything I needed to know about pet chinchillas. There were very few articles about pet chinchillas in the veterinary journals back then, and the only textbook at that time was “The Biology and Medicine of Rabbits and Rodents.” Unfortunately that textbook focused only on lab animal rodents and did not even include chinchillas. It would be another six years before the pink book (“Ferrets, Rabbits, and Rodents, Clinical Medicine and Surgery”) would be published. The pink book was a giant step forward for pet chinchillas.
Chinchillas are prone to several different types of diseases of the digestive tract, and I knew very little about any of them when I graduated. Any illness, stressful condition or painful condition can cause a gastrointestinal problem in a chinchilla. In addition there are some infectious causes (bacteria and parasites) to go along with those noninfectious causes of gastrointestinal diseases. Most of these disorders will cause rather vague signs of a gastrointestinal problem, such as anorexia, lethargy and abnormal feces.
Diarrhea and soft feces are common in pet chinchillas. Either condition can be from an inappropriate diet or from a sudden change in the diet. Chinchillas require a very high fiber diet, similar to what rabbits need. It is currently recommended for the diet to be roughly 75 percent hay. Unfortunately, some owners feed mostly a pelleted diet with only a small amount of hay. The low fiber content and higher carbohydrate level of a low hay diet will cause a loose stool and eventually cause a problem with the bacteria in the GI tract. It can even cause an overgrowth of yeast in the stomach. Most chinchillas can be treated by simply improving their diet with a high-quality hay, such as timothy hay or other grass hays. Chinchillas with more severe cases of GI trouble may need an antibiotic, fluid therapy and a probiotic to get things back to normal.
A constipation problem can also occur from a sudden change in their diet or if the chinchilla becomes dehydrated from an illness. This will cause the food in the cecum to become firm and hard. Sometimes the food will become impacted, making it almost impossible to pass through the rest of the GI tract. Treatment for this includes rehydrating the chinchilla with sub-cutaneous fluids and giving oral fluids to rehydrate the food in the cecum. Similar to a horse with colic, exercising the chinchilla and massaging the abdomen can help break up the food in the cecum and make it easier to pass. Most of these cases do not need an antibiotic, but they do need an improved diet and some pain management.
Chinchillas can also have an intestinal infection with the parasite Giardia duodenalis. This seems to be a more common problem for younger chinchillas. Giardia can cause diarrhea, lack of appetite and weight loss. Giardia can become a serious and even fatal problem if combined with a bad diet or a stressful situation. Treatment of chinchillas with Giardia is very similar to the treatment for puppies and kittens; however, it is safer to use Panacur in chinchillas instead of the antibiotic Flagyl. Most chinchillas will improve with the appropriate medication and fluid therapy. It is also important to disinfect the cage and play areas to prevent reinfection.
Chinchillas seem to be prone to problems with their urinary tract. Male chinchillas are prone to developing a “fur ring” around the base of their penis. This can be big enough that the male can no longer retract the penis into his prepuce. This will cause the penis to enlarge and become painful. It may even cause an obstruction of the urethra and prevent the chinchilla from urinating. Treatment for this includes a veterinarian removing the “fur ring” and smegma and applying a topical antibiotic ointment. More severe case may require an oral antibiotic and pain medications.
Chinchillas are also prone to bladder stones. In a recent article from the University of Minnesota, almost 90 percent of the bladder stones were made up of calcium carbonate. It is not clear why chinchillas are prone to calcium carbonate stones, but it may be related to their concentrated urine. Chinchillas are originally from the high elevations of the semi-arid Andes Mountains. Wild chinchillas get almost all of their water intake from the vegetation they eat and rarely drink water. Their kidneys do an excellent job of conserving water, which results in a concentrated urine. When a chinchilla is fed one of the high calcium containing hays like alfalfa hay, then excessive amounts of calcium may end up in the urine. The calcium in the urine may develop into a calcium carbonate bladder stone. Back when I was in school, alfalfa hay was routinely recommended, but now it is recommended not to feed alfalfa hay on a regular basis.
Chinchillas are very prone to heat stress and heatstroke. Chinchillas must have a cool and dry environment. When the temperature gets above 80 degrees Fahrenheit, they start to get heat stressed. If the temperature gets above 85 degrees, they are likely to suffer heatstroke. Humidity will also add to the heat problem. Treatment for heatstroke is similar to the treatment for dogs, cats and ferrets, but, unfortunately, chinchillas do not respond to treatment as well as other small mammals and may not survive.
Overall I had to learn a lot about these little rodents from South America after I graduated from vet school, and I am glad I did. Chinchillas are usually friendly and make great pets. With the proper diet, dust bath and cool temperatures they can lead a long and healthy life.