The chinchilla is a domesticated rodent that originally lived in the high Andes Mountain region of South America.  The chinchilla was hunted to near extinction in the early 1900's.  Most of the chinchillas in the United States today are descendants of 11 animals brought to California in 1923.

The chinchilla is now cultivated in large numbers for its luxurious pelt.  Over the years, the chinchilla has been the object of legitimate and illegitimate breeding schemes.  In addition, chinchillas have been used for medical research.

Chinchillas also are kept as pets.  Initially, it is the chinchilla's beautiful coat that attracts attention; however, it is this docile animal's personality that ultimately wins over it's many friends.

Characteristics
The ears of the chinchilla are large, thin, and "bat-like", and the inner ear of the chinchilla is very large.  Together, these traits are related to the chinchilla's ability to communicate over long distances in the wild.

The incisors, or front teeth, of the chinchilla grow between 2 and 3 inches a year.   The molars also grow throughout the animal's life.

The chinchilla's gastrointestinal tract is long - the intestines and colon measure over 3.5 years in the adult animal.  Like rabbits or horses, chinchillas ferment the fiber in their diet and eat a special portion of the stool passed every day called cecotropes or soft feces.

The female chinchilla has four mammary glands, one at each inguinal region and one on each outside rib.  The female reproductive tract is closed by a membrane except when she is in heat or is pregnant.  The external portion of the female chinchilla's reproductive tract is cone shaped, leading to confusion in determining sex.

In the male chinchilla, there is no true scrotum.  The testicles may be found in the inguinal canal area just below the skin between the back legs.  The sex of young animals is best determined by the distance between the openings of the urinary tract and the rectum.  In the female, and anus and urinary opening are close together, whereas the male has a wide separation between the openings.

Newborn chinchillas are quite precocious.  They are born fully furred, with their eyes open, and can soon walk.  They can begin eating solid food within a week after birth but may not be fully weaned for 6 to 8 weeks.

• Adult weight:  Males = 400-500 grams ; Females = 400-600 grams
  
• Life span:  Usual = 10 years; maximum = 20 years
  
• Body temperature: 96.8 -100.4F
  
• Heart rate: 100 beats/minute
  
• Puberty: 8-10 months
  
• Breeding season: November - May
  
• Estrous cycle: usual 40 days; range 16 - 69 days
  
• Litter size: average 2; range 1-6
  
• Litters per year: 2
  
• Birth weight 35 grams
  
• Eyes open: yes
  
• Wean: 6-8 weeks
  

Housing and Environment

Although chinchillas can survive in a variety of environments, these animals thrive best in conditions that are similar to their Andean homeland.  Cold temperatures are well tolerated - even stressed in the pelt industry - stimulate the chinchilla's thick coat.  In turn heat stroke is a significant problem, especially in humid environments.  Wire cages are traditionally used as housing for chinchillas.   The cage should be at least 24" x 24" x 18".  To help reduce foot problems, a solid flooring should be provided in a portion of the chinchilla's wire cage.  Chinchillas enjoy climbing and jumping; thus a multilevel cage is recommended for pet animals.  Adding untreated wood shelves to the cage is helpful, as chinchillas prefer to be in high places.

Commercially raised chinchillas are typically kept in polygamous caging arrangements.   A single large cage may be used, but due to the aggressive behavior of dominant females, escape boxes must be provided for males and less dominant females.  More commonly, a system of small cages connected with a runway us used in which the females are confined to their cages by a metal disk fastened around their neck.  This prevents the females from leaving while males come and go from the cages at will.

Chinchillas are fanatical in their grooming habits.  This behavior necessitates dusting or bathing them in a mixture of silver sand and Fuller's earth, which is available at pet stores or from chinchilla breeders.  Typically, a small container of the dusting mixture is placed in the cage for a short period of time daily for the chinchillas to clean themselves.  If the dust is left in the cage for long periods of time, it will become soiled with feces and hidden bits of food.

Diet
A good quality grass hay supplemented with commercial chinchilla pellets should be fed to chinchillas.  Food should be constantly available.   Obesity is rarely, if ever, a problem with chinchillas fed primarily a hay diet.

Fresh fruits and vegetables may also be used as treats and supplements, provided the diet does not change abruptly and the amount of fiber in the diet stays high.  Fresh foods should constitute about 10% of the diet.  Dried fruits and nuts - not to exceed 1 level teaspoon per day - may be fed.  Pelleted diets alone may be too high in digestible calories and may pre-dispose animals to enteritis problems.

Handling
The chinchilla is a docile animal that is relative easy to handle.  When handling a chinchilla, lift it with one hand by the base of its tail, while the other hand is used to support the body or lightly restrain the animal at the chest.  Chinchillas respond to light tough.  If frightened or roughly handles, the chinchilla may release a portion of its hair.

It is not advisable to allow chinchillas to roam unsupervised outside of their cages because they run very fast and can disappear into small places.

Common Diseases and Syndromes

External

Bite wounds and the subsequent abscesses are commonly seen in chinchillas kept in groups.  Surgical removal of the abscesses is usually more successful than incision and cutterage.  Treatment with an appropriate antibiotic may also be indicated.

Dermatophytosis (ringworm) can occur but is not common in the chinchilla.   Treatment consists of using dips and oral medication.  Ringworm may be spread from animals to humans, or vice versa.  Affected animals should be isolated.   Any human-brand anti-fungal powder mixed with the daily dusting powder may help prevent the spread of the fungus among animals.  As with any disease, a veterinarian should be consulted.

Fur chewing and "barbering" (chewing the fur of other animals) are common problems seen with animals under social stress or housed in colonies.  The most dominant animal responsible for the chewing (the barber) may have to be removed from the group to correct the problem.

Penile hair rings are a critical problem with chinchillas.  Affected males groom excessively, act uncomfortable or ill, and may strain to urinate or may not be able to urinate at all.  Treatment involves careful removal of the hair ring by a veterinarian.

Digestive
The gastrointestinal system includes the stomach and intestines.  Enteritis complex, (inflammation of the intestines, affects chinchillas and includes mucoid enteritis, diarrhea, and fecal impaction.

Enteritis complex may be the most common problem of the digestive tract of chinchillas.   This condition involves  disruption of the complex system responsible for fermentation of non-digestible fiber in the diet. Factors involved in enteritis complex include changes in diet, effects of antibiotics, stress, and genetic predisposition to gut dysfunction.  Diets high in sugars or protein or low in fiber may cause changes in the fermentation process in the cecum, leading to changes in pH  and motility, which in turn lead to enteritis.  Additionally, some antibiotics that affect the normal bacteria of the hindgut (penicillin, cephalosporin, erythromycin, clindamycin, and lincomycin)  allow overgrowth of bacteria found in the intestinal tract, which can cause enteritis.

Signs of enteritis complex include loss of appetite, tooth grinding, painful and possibly bloated abdomen, crying or moaning, lethargy and reluctance to move, diarrhea, or absence or stool, and sudden death.  Treatment includes the use of "safe" antibiotics, fluid therapy, and correction of the diet.

Dental
The chinchilla's incisors and molars grow throughout its life, and it is not uncommon to see older chinchillas with overgrown molars.  These can be caused by a change in the angle of growth of the tooth due to age or by infection of the tooth roots.   Signs of the disease may include lessened or total loss of appetite, drooling and wetness of the fur around the chin and neck, tooth grinding, partially closed eye(s) or excessive tearing, and lumps on the upper or lower jaw.

Heat Stroke
Chinchillas are uneasy at temperatures at or above 80F, particularly if the humidity is high.  Chinchillas may develop problems from heat year-round.  Cages placed in the sun in from of a window will lead to problems even  in the coldest of months.   Chinchillas that are adversely affected by heat become prostrate, pant, and have an elevated temperature.  In addition, their face and neck may be covered with saliva.   Advanced cases may show a bloody discharge from the nose or mouth and/or a bluish color to the tissues of the mouth.  Some chinchillas may even die from heat stroke. 

Treatment consists of cooling the chinchilla by spraying it with cool water or dipping it in a cool bath.   Careful administration of intravenous fluids is indicated in advanced cases.  Body temperature must be closely observed, as many chinchillas have difficulty regulating their body temperatures after being cooled.