Continuing Education
The Handling and Care of
the Chinchilla
Sabrina Timperman, DVM Chinchillas (“chins”) are generally gentle This program was reviewed and approved by the AAVSB RACE program for 1 hour of continuing education in jurisdictions which recognize AAVSB RACE approval. Please contact the AAVSB RACE program if you have any comments/concerns regarding this program’s validity or relevancy to the veterinary profession.
animals with playful and loving personalities, and their popularity as pets is growing steadily. They have a very dense, soft coat that made them very popular in the fur trade for years, and they were often hunted for their coats. The chinchilla’s natural habitat is in South America high up in the Andes Mountains. For a variety of reasons, including diminished natural habitat and over-hunting, the number of wild chinchillas are diminishing in spite of efforts to protect them.1 Chinchillas are rodents, and like guinea pigs, belong to a rodent group known as caviomorphs. Caviomorphs have small litters born after a relatively long gestation.
The average gestation for a chinchilla is 4 months, but the gestation of the most common species, Chinchilla langier, is 105 to 118 days. On average, there are 2 (1 to 6) kits per litter. When the kits are born, they are precocious with their eyes open, have fur and look very much like miniature adults. They are able to move around immediately. This is in contrast to another group of rodents, myomorphs, which consist of rats and mice. Myomorphs breed very rapidly and have a shorter pregnancy of 20 to 22 days; their offspring are altricious (entirely dependent on the parent) and are born naked.1
There are two species of chinchillas, but all domesticated chinchillas are believed to be
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Continuing Education Chinchilla, continued descendents of the Chinchilla lanigera, the long-tailed chinchilla.1
Physical characteristics Chinchillas are the size of a large squirrel and have small, compact bodies, bright eyes and large broad ears that are used to help the animal stay cool in warm weather. They also have veins that are very close to the surface of the ears which allow for cooling of the blood, helping to prevent overheating. They have a long, bushy tail that helps to balance them while jumping, hopping and running. Chinchillas’ strong hind legs allow them to be very agile, and they are known for their acrobatic and lively antics, especially when they are young. Their front limbs are shorter and have five digits each with a blunt claw. They use their digits much like fingers and hold on to their food while balancing on their hind feet. Like other rodents, chinchillas have strong, open-rooted teeth that grow continuously throughout their lives. This can cause problems when the teeth are not properly aligned and their natural wear is disrupted. A chinchilla is born with its teeth, which start off white. As they age, the color of the teeth changes from white to yellow.2 White teeth in an adult chin are abnormal and is evidence of a calcium deficiency.3 Due to their constant gnawing and chewing, healthy teeth are crucial for the health and vitality of the chinchilla, and dental problems are one of the most common reasons a chinchilla is taken to the veterinarian.
a penis. However, the anogenital distance from the urinary papilla to the anus is closer in the female than the male. A considerable amount of skin separates the penis and anus in the male, leading to a larger anogenital distance allowing for accurate sexing.4 Adult females also tend to be larger at 400-600 grams than their male counterparts with adult weights of 400-500 grams.4
Behavior Chinchillas are nocturnal and crepuscular (active at twilight or just before sunrise). Because they are prey animals, they are constantly on guard and can easily be frightened or alarmed. Chinchillas love to move about and are usually good climbers, jumpers and leapers. However, traumatic fractures often occur when they are startled, improperly grabbed by the leg or if their leg gets caught in the cage bars. It is not uncommon for a chinchilla to be presented to the veterinary clinic with a broken tibia.4
Environment issues
Chinchillas can be sexed by examining the anogenital distance. The large urinary papilla of a female can often be confused for
Many of the problems seen in chinchillas stem from inadequate or improper care; so, a basic understanding of a chinchilla’s husbandry requirements is helpful in diagnosis and treatment. The first thing a chinchilla needs is adequate housing. It’s enclosure should be large enough to allow for plenty of jumping and climbing. Due to their nervous nature, chinchillas do best when their housing is not approachable on all four sides. Putting the enclosure in a corner alleviates this problem and acts to diminish their level of stress, so that they are less likely to attempt sudden escapes with resulting traumatic injuries. The enclosure should always be put in a cool, draft-free room. Chinchillas are very susceptible to heat stroke and can easily become overheated, making a cool environment crucial to their health. Solid floor caging is best as their feet can get caught and injured in a wire mesh floor. They can also develop hair loss and sores on their feet due to wire meshing.1,2,3,4 A tile can be used for cooling purposes and to protect their feet.
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Its plush fur coat is one of the chinchilla’s most appealing features. Its density is due to the fact that each hair follicle has 50 hairs (humans have one hair per follicle.)3 As a result of this dense coat, chinchillas aren’t prone to ectoparasites like fleas, ticks, and mites, but they require dust baths to keep their coats healthy.3
In terms of substrate, there is a wide ranging opinion on what makes the best floor covering. Each has its advantages and disadvantages. Many suggest bedding should consist of soft wood shavings or recycled paper bedding. Inappropriate beddings, including cedar wood chips (which can contain potentially dangerous resins), saw dust (which is too fine leading to sneezing and eye irritation) and newspaper (which can contain poisonous chemicals) should be avoided.1 As mentioned earlier, a dust bath is required to allow the chinchilla to properly care for its coat. Daily dust bathing prevents the fur from becoming matted with oily secretions. Too much time in a dust bath, however, can result in dry skin and conjunctivitis. Chinchillas should be placed in a dust bath daily or several times a week but should not have free access all the time. Commercial chinchilla dust is available at many pet stores, and the dust should be placed in a shallow pan at a depth of 1-2 inches, allowing enough room for the chinchilla to easily move and roll around.
Nutrition and Feeding Chinchillas are herbivores and are classified as hindgut fermenters, like rabbits and horses. The specific nutritional requirements of the chinchilla are not completely known, but they thrive best when eating a high fiber diet. Commercial pelleted diets are available and the accepted formula for chinchilla pellets are 16-20% protein, 2-5 % fat and 15-35% fiber.4 Pellets should be formulated primarily from timothy hay. Hay is also another essential component of the diet because it helps to provide a high level of fiber. Hay helps to wear down the teeth and provides roughage to regulate stool. Fiber helps to propel food through the digestive tract. Inadequate levels of fiber can lead to gastrointestinal disturbances such as constipation. Small quantities of fresh foods such as greens, dried fruits, sunflower seeds and raisins can be given as well. Excessive feeding of fresh greens,
Continuing Education
hay that is too young and wet and damp hay that can contain molds can lead to diarrhea and a disturbance in the bacteria that normally populate the GI tract. Sudden diet changes can also predispose chinchillas to diarrhea. Clean, room-temperature water provided in a water bottle should always be available.1,2,3,4
Clinical Techniques Handling and Restraint When a chinchilla is brought into a clinic, it is very important to avoid creating an injury or worsening an existing one, so proper handling and restraint is a must. Never lift a chinchilla up by its tail or ears, and be aware that a chinchilla can lose a patch of fur if it is roughly grabbed. This is called fur slip and is a defense mechanism present in chinchillas to protect against predators. Following fur slip, the hair regrowth may take as long as several months and may grow in a slightly different color. Chinchillas are skittish, so talking in a soothing voice can be helpful. Moving in a direct, confident manner is advised. When attempting to remove a chinchilla from its cage, place one hand under the chinchilla’s body or around the scruff on its neck to support it and use the other hand to grasp the base of the tail. To carry the chinchilla while you are walking, support it against your chest, holding the base of the tail with one hand to prevent jumping. The other hand should be used to support the abdomen.4
Physical Exam If possible, examining the chin from a distance before taking it out of its enclosure is important to assess not only its demeanor, but also its ability to sit and walk normally. When doing a physical exam on a chinchilla, you must recognize what is normal and what is abnormal. A healthy chinchilla has bright eyes. It is alert, inquisitive, interested in its surroundings and does not appear overly groggy or sleep excessively. Its tail is curled and carried high. Looking at all aspects of the animal is important. Develop a routine or check list in your head as you
Table 1 Venipuncture Hints 4,6,7 Site
Needle
Syringe
Jugular vein
22-25 gauge
1-3 ml
Vein is very superficial and skin thinner than guinea pig. Can take larger sample. Restraint may stress the animal. If stressed, stop procedure. Can do under anesthesia. Lateral saphenous vein
25-27 gauge
Insulin or tuberculin
Shave fur from the area and wet with alcohol. Venipuncture from several sites to collect enough blood may be necessary. Cephalic vein
25-27 gauge
Insulin or tuberculin
Shave fur from the area and wet with alcohol. Venipuncture from several sites to collect enough blood may be necessary. Cranial vena cava
22-25 gauge
1-3 ml syringe
Risk of subsequent traumatic bleeding into thoracic cavity or pericardial sac. Femoral Vein
22-27 gauge
1-3 ml syringe
Located on medial side of the leg so more difficult to access. Tail vein
25-27 gauge
1 ml syringe
Bleeder holds tail and inserts needle directly on the ventral midline one-third to halfway down the tail. Advances needle at 30-40 degree angle. Vasodilate by applying warm compress to tail.
examine the patient, starting at one end and moving down the body, checking each body system. Record all vital signs, including weight, temperature, heart rate and respiratory rate. A sick chinchilla may be quiet, listless, dull or hunched in a corner. Usually, it avoids contact with people. It may have hair loss, weight loss or a loss of interest in its surroundings. Sneezing, wheezing, coughing and nasal and ocular discharge are abnormal findings, just like in feline and canine patients. Check for strong odors, sores or pain on abdominal palpation. Auscultate the heart and lungs. Examine the feces. Normal fecal pellets are elongated, firm and just barely moist. Look for evidence of diarrhea, such as smeared feces around the anus, or a lack of bowel movements indicating constipation. Drooling can also be an
indication of a problem, and an examination of the teeth is crucial because chinchillas often develop tooth abnormalities. Do the oral exam last because this tends to stress the animal, and stress can affect your physical exam findings.4 Again, teeth should be yellow (because of iron deposition) and properly aligned. To better visualize the cheek teeth, use a speculum or otoscope while an assistant restrains the animal by supporting its weight in one hand and holding both forearms.4
Anesthesia Many diagnostic procedures and treatments are more easily performed under general anesthesia. Premedication with sedatives can decrease the amount of anesthetic agents used and shorten recovery time. It also helps to reduce stress and anxiety caused by anesthetic induction.
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Continuing Education Chinchilla, continued Interesting Facts about Chinchillas1,2,3,4 1. Chinchillas are virtually odorless
most of the time. 2. Chinchillas have 20 teeth and are born with their teeth. 3. Chinchillas can’t vomit. 4. Chinchillas produce two types of feces. 5. Healthy chinchillas pass more than 200 fecal pellets a day. 6. Chinchillas’ incisors grow 5 to 7.5 cm (2-3 inches) per year. 7. Chinchillas primarily eat and excrete feces at night. 8. Chinchillas have two cervices and three pairs of mammary glands. 9. Chinchillas are seasonally polyestrous in the wild like the cat. 10. Chinchillas have an auditory sensitivity similar to humans and large tympanic bullae so they are often used in hearing research.
Physiologic Values2,3,4,7 Average Life Span as Pet:10 years Weight: M ales 400-500 g Females 400-600 g Heart Rate: 200-350 bpm Respiratory: Rate : 45-80/min Temperature: 37-38 C (98.6 – 100.4 F) Sexual Maturity: 8 months Weaning Age: 6-8 weeks Dental Formula: 2(I1/1 C0/0 P1/1 M3/3) GI Transit Time: 12-15 hours
Chinchilla Taxonomy2 Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrat Class: Mammalia Subclass: Eutheria Order: Rodentia Suborder: Caviomorpha or Hystricognathi Superfamily: Chinchilloidea Family: Chinchillidae Subfamily: Chinchillinae Genus: Chinchilla Species: langier and brevicaudata
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Following premedication, induction can be accomplished with inhalant anesthetics given via mask or induction chamber. Intubation is difficult in rodents but is indicated in procedures involving thoracotomy and those disrupting respiratory neuromuscular signaling. It is also ideal for oral/dental procedures. Pre-anesthetic fasting is not required because chinchillas cannot vomit. However, a fast of 1-2 hours may be necessary to minimize the risk of food being left in the mouth and carried into the trachea during intubation.5 The inhalant anesthetics, isoflurane and sevoflurane, are the preferred agents for induction because they allow rapid induction, recovery and control of anesthetic depth.4,6 However, parenteral anesthesia can also be used to induce anesthesia.4 Various combinations of drugs, such as ketamine and diazepam or ketamine and xylazine or ketamine and acepromazine, may be used.
Blood Collection Once the physical exam is performed, samples can be collected to help to evaluate health or narrow down the differential list. Blood collection from a chinchilla can be challenging. One of the most important facts to keep in mind is how much you can safely take from a chinchilla without hurting the animal. An adult chinchilla has a total blood volume of 27-48 ml (or 7 mL/100 g). Approximately 7 – 10 % of blood volume can be safely collected from a healthy chinchilla, making a maximum single sample volume of approximately 3 – 5 mls (or 0.5-0.7mL/100g) acceptable.4,6 Small samples of blood can be collected from the cephalic and lateral saphenous veins, but due to their small size and ease of collapse, this approach can be difficult. If these sites are to be used, it is best to use an insulin or tuberculin syringe and a narrow-gauge, short needle.4 The jugular vein is the preferred site for collection of a larger sample. Jugular venipuncture is best performed under anesthesia to minimize stress to the animal. By placing the patient
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in sternal recumbency, extending the front limbs over the edge of table and the head and neck toward the ceiling, you can better visualize the vein.4 Blood can also be drawn from the ventral tail vein. The chinchilla can be restrained by holding its back up against the restrainer’s belly with its ventrum toward the person taking blood. The person taking blood holds the tail with one hand and, midway up the tail from the tip of the tail to its base, inserts a small needle at a 3040 degree angle directly at midline. The sample is collected gently, with the plunger drawn back slowly.6 Table 1 lists some of the equipment needed to collect blood.
Other tests Cystocentesis, similar to the small animal technique, can be performed to collect a urine sample. This also is more easily done when the animal is under anesthesia . Normal chinchilla urine has a pH of 8.5 and may contain some calcium carbonate crystals and squamous epithelial cells.7 Urine does not often contain casts, bacteria, erythrocytes and leukocytes unless there is a problem. If abnormalities are suspected, radiographs taken under anesthesia are another useful diagnostic tool.
Common Diseases Affecting Chinchillas Trichobezars (Hair balls) Just like in cats and rabbits, chinchillas can acquire a mass of hair in its stomach and intestinal tract, called a trichobezar. Trichobezars are common in animals that are fur-chewing and often can be associated with a low-fiber diet. Clinical signs include lethargy, anorexia, and abdominal pain that causes a reluctance to move. The treatment protocol may consist of IV or SC fluids, gastric motility stimulants and force feedings of a high fiber diet.4
Constipation Inappropriate diet is one of the most common and important causes of gastrointes-
Continuing Education
tinal disturbances in chinchillas. Feeding a diet with too many pellets and not enough fiber is one of the leading culprits. Obesity, inadequate fluid consumption and lack of exercise can also contribute to the development of constipation. If the constipation is not properly treated, it can ultimately lead to rectal prolapse. Signs include straining to defecate, with abnormal feces that are small, hard and possibly blood tinged, with fewer pellets actually being passed. Treatment involves increasing dietary fiber by adding fresh fruits (such as apples), fresh vegetables (such as carrots) and hay. If dietary change alone does not resolve the constipation, over-the-counter feline hairball remedies can be used to lubricate the feces, allowing them to pass more easily. Also, motility enhancers such as cisapride may be recommended if intestinal blockade is ruled out. Weight reduction by increasing the chinchilla’s level of exercise and eliminating snacks can also be beneficial.1,2,4,6,7
Gastroenteritis This is a serious inflammatory condition of the gastrointestinal tract that can have both infectious and noninfectious causes. The gastrointestinal tract of the chinchilla is normally colonized by a number of beneficial gram-positive bacterial species that are crucial to the normal functioning of the digestive tract. If this delicate bacterial environment is upset, or the normal flora and fauna of the GI tract is altered, then harmful or pathogenic bacteria can overgrow, leading to gastroenteritis. Noninfectious causes include improper diet and inappropriate or extended use of antibiotics. This leads to an overgrowth of harmful bacteria (such as Escherichia, Clostridium, and Salmonella). Infectious causes include protozoa, bacteria or parasites. The disease can present in acute or chronic form and can be difficult to treat. Animals may present with diarrhea, anorexia, bloating, lethargy, weight loss, abdominal pain and death, which can be sudden. Due to the complexity of the etiology, determining the exact cause can be challenging. Diagnostics may include fecal flotation
and/or culture. Treatment includes supportive care with fluids, electrolytes, a quiet stress-free environment, an analgesic for pain management and perhaps a probiotic. Additional treatment depends on the cause and includes appropriate use of antibiotics, antiparasitics and antiprotozoals.4,7,8
Malocclusion Malocclusion resulting from uneven wear of continuously growing teeth is another common disease of chinchillas. Incisors, molars and premolars can all be affected by abnormal tooth elongation. Causes include genetics, infections, poor husbandry, improper diet and trauma. The chinchilla can present with anorexia, ptyalism (slobbering), pawing at the mouth, changed food preferences, dysphagia, weight loss, starvation and death. To properly diagnose malocclusions, radiographs or other imaging modalities such as CT scan should be implemented.4 Treatment involves correcting the diet, teeth trimmings, filing down of the spikes and reducing crown height of the teeth.
Skin Diseases Bite wounds, fur chewing, matted fur, alopecia and other skin issues can all be caused by improper husbandry. For
example, keeping chinchillas in a humid environment or not providing access to a dust bath can contribute to the development of matted fur. In addition, keeping a chinchilla housed in an improper enclosure, in a stressful environment (such as around loud noises), housing too many chins in one enclosure, or keeping two chins together who are not compatible can lead to fur chewing. A chinchilla can chew at its own fur or its companion causing a coat that appears moth-eaten. Although there may be other reasons for this common cause of fur damage, the belief that fur chewing is a behavior disorder, due to different kinds of stress, is the prevailing and most popular theory. Since the causes of stress can be multifaceted, treatment varies and most often is centered on reducing or eliminating the instigating stress.1,4,7 Another less common dermatologic condition that chinchillas acquire is dermatophytosis. Although the disease is uncommon, it has zoonotic potential, so monitoring is important. Dermatophytosis is also known as ringworm and is caused by a fungus. It can be introduced to the chinchilla via contaminated hay or bedding. Trichophyton mentagrophytes is the dermatophyte that
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Continuing Education Chinchilla, continued most often causes ringworm in chinchillas.4 Dermatophytosis produces scaly circular areas of hair loss, seen most commonly on feet, face and ears. To diagnose, a fungal culture is required. Trichophyton mentagrophytes does not fluoresce under ultraviolet light so a Wood’s lamp is not appropriate for diagnosis. Topical treatment involves antifungal shampoos and rinses. Systemic antifungal medication, such as itraconazole, ketoconazole and terbinafine, may also be prescribed by the veterinarian.4
Heat Stroke Since their natural habitat is high in the mountains, chinchillas are very susceptible to high temperatures and high humidity. The ideal environment depends on both the temperature and the humidity. As a general rule, the environment is too warm if the Fahrenheit temperature plus the humidity is greater than 150. For example, a temperature of 85 degrees Fahrenheit + 70 % humidity = 155, indicating the environment is dangerously warm.4 Chinchillas are for the most part comfortable in a temperature range of 63 to 77 Fahrenheit with a humidity of 30 to 50 percent.2 If exposed to elevated heat and humidity, a chinchilla may develop heat stroke. Signs of heat stroke include weakness, labored rapid breaths, bright red mucous membranes, dehydration, swollen ear veins and reddened ears.4 The animal can become unresponsive, comatose or present dead. Treatment involves cooling the animal down safely by immersing the chinchilla in tepid water while making sure to keep its head above water.2 Giving fluids can also be beneficial; IV fluids are essential if the animal is in shock.
Treatment Techniques Medications can be given by several different routes, including oral, intramuscular, subcutaneous and intravascular. Hiding medication in a raisin or other tasty treat is one simple way of getting chinchillas to ingest medication. Liquid medication can also be squirted easily into the corner of the mouth behind the incisors, while
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subcutaneous injections can be put under the skin in the neck and flank area. Intramuscular injections can be given in the lumbar muscles. For both subcutaneous and intramuscular injections, it is best to use a 23 to 25 gauge needle.7 If fluids are required, they may be given subcutaneously in the neck region or intravenously though a catheter in a peripheral vein. Catheterization of peripheral veins is often easier to accomplish when the animal is under anesthesia. These veins are small and hard to access. As a result, sometimes it is necessary to perform a jugular cut- down for an indwelling catheter. Force-feeding a critical care formula or softened guinea pig pellets is sometimes necessary, especially if the animal is anorectic. 4,6,7 This, as well as other supportive care, is a crucial component of the treatment plan. Eliminating stress and providing the proper husbandry and proper nutrition can go a long way in helping the patient to recover. At times euthanasia may be necessary, and the preferred method is lethal injection. Masking the patient down with an inhalant anesthetic prior to the intravenous or intracardiac injection of euthanasia solution is recommended.7
Conclusion: Although chinchillas require very specific care and maintenance, owning a chinchilla can be a rewarding experience. Each chinchilla has its own unique personality, and the bond that can formed through interacting and caring for these animals can last for years. References 1. Alderton D. Animal Planet Chinchillas. Neptune City, NJ: T.F.H. Publication Inc.; 2009 2. Vanderlip SL. The Chinchilla Handbook. Hauppauge, NY: Barron’s Education Series, Inc.; 2006
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3. Pavia A. Chinchillas. Neptune City, NJ: T.F.H. Publications Inc.; 2009 4. Quesenberry KE, Carpenter JW. Ferrets, Robbits, and Rodents Clinical Medicine and Surgery. 2nd ed. St. Louis, MO: Saunders; 2004 5. Bennett A. Small Mammal Anesthesia—Rabbits and Rodents. Paper presented at: Atlantic Coast Veterinary Conference 2009; Urbana, IL. http://www.vin.com/Members/Proceedings/ Proceedings.plx?CID=acvc2009&PID=pr532 31&O=VIN. Accessed September 21, 2011. 6. Harkness JE, Turner PV, Woude SV, Wheler CL. Biology and Medicine of Rabbits and Rodents. 5th ed. Ames, IA: Blackwell Publishing; 2010 7. Ballard B, Cheek R. Exotic Animal Medicine For The Veterinary Technician. 2nd ed. Ames, IA: Blackwell Publishing; 2010 8. Kennedy AH. Chinchilla Diseases and Ailments. Toronto, Canada: Fur Trade Journal of Canada; 1952
Acknowledgements Laurie Buell, MS, LVT
About the Author Sabrina Timperman, DVM, graduated with a B.A. in Biology from Wagner College and attended Louisiana State University School of Veterinary Medicine, where she graduated in 2005. Currently, she is an assistant professor at Mercy College.
Continuing Education
Chinchilla Quiz 1. The chinchilla diet is best described as: a. Herbivore b. Carnivore c. Omnivore d. Insectivore 2. The adult chinchilla should have what color teeth: a. White b. Yellow c. Gray d. Brown 3. a. b. c. d.
Chinchillas are from which order: Carnivora Rodentia Lagomorphia Perissodactyla
4. The average life span of a pet chinchilla is: a. 2 years b. 6 years c. 10 years d. 12 years 5. a. b. c. d.
7. a. b. c. d.
Chinchillas are very prone to: Hypothermia Heatstroke Metabolic bone disease Mites
8. The best place to collect a larger blood sample from the chinchilla is a. Cephalic Vein b. Lateral Saphenous Vein c. Jugular Vein d. Ear Vein 9. The prevailing theory on the cause of fur chewing is: a. Parasitic b. Infectious c. Behavior Disorder d. Endocrine Disorder
10. The following chinchilla disease is zoonotic: a. Fur slip b. Mites c. Trichobezoars d. Dermatophytosis
This article is worth one continuing education credit and will be accepted for grading until December 31, 2012. To receive credit, please complete the quiz online at www.VetMedTeam.com. *Due to updates and changes authorized by NAVTA, the online quiz may not be the same as the printed exam within the NAVTA Journal. Read each question thoroughly and answer it as it appears in the online exam. Please do not simply copy your answers from the printed version.
A wild chinchilla is considered: Monoestrus Diestrous Polyestrous Seasonally Polyestrous
6. A female chinchilla: a. H as a larger anogenital distance then the male b. Has a gestation of 20-25 days c. Gives birth to precocious young d. Gives birth to altricious young
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