Gerbils

Question 1

Describe the taxonomy of gerbils

Answer 1

Order: rodentia
Suborder: myomorpha
Family: cricetidae
Sub-family- gerbillnae
Genera: meriones
Species: meriones unguiculatus (mongolian gerbil_
- the one that is in commercial trade

Question 2

What are the other names for meriones unguiculatus?

Answer 2

Desert or sand rats or jirds
- they are native to arid regions of Mongolia, NE china and western Machuria
-live in deserts, steppes, grasslands, and bush country (everything except deep forest)

Question 3

Describe the history of the mongolian gerbil

Answer 3

-all captive animals today were derived from 20 breeding pairs captured in mongolia in 1935 and taken to japan, 11 breeding pairs were brought to the US in 1954
-breeding has produced a lot of color variations
-they were used as an animal model for filariasis (bloodworms)
-illegal in some areas of the Us including california (potential to be invasive)

Question 4

T/F: females are usually larger than male gerbils

Answer 4

False- the other way around

Question 5

What is the lifespan of gerbils?

Answer 5

3-4 years (aka longer than hamsters)

Question 6

Describe the size of gerbils in relation to rats and mice

Answer 6

Smaller than a rat, larger than a mouse

Question 7

What is the urine volume of gerbils?

Answer 7

3-4 mL/day- very small compared to other rodents
-dont make a mess of substrates compared to other rodents and drink less water

Question 8

Describe the basic anatomy and physiology of gerbils

Answer 8

-hair on the back and sides is darker than the underbelly
-long furred tail with a tuft of hair at the tup
-prominent incisors that grow continuously
-small cheek pouches that are not extrudable

Question 9

T/F: gerbils contain harderian glands, similar to rats and mice

Answer 9

True-produce red tears

Question 10

Why do gerbils groom themselves more when producing porphyrin from the harderian glands?

Answer 10

The porphyrin is very irritating to their skin
- can be found in other areas other than the eyes due to grooming behavior
- what to do: reduce stress in environment, wash area (water, not saline), dry up with q tip or cornbread meal

Question 11

What is unique about the adrenal glands of gerbils?

Answer 11

They are very large

Question 12

T/F: the mid ventral abdominal sebaceous glands is only active in males

Answer 12

False- active in both sexes but the male gland is typically larger than the female counterpart
- used to mark territory and pups

Question 13

Describe the behavior of gerbils

Answer 13

-gregarious, active burrowers
-active in both the day and night (peak), not crepuscular
-adapt to a wide range of temperatures (most commonly kept at room temp)
-do not hibernate or estivate
-generally docile, but can bite
-foot stomping is a sign of aggression or excitement (warning that they may bite)
-monogamous pairing/breeding

Question 14

T/F: anogenital distance is greater in male gerbils than female gerbils

Answer 14

True

Question 15

Describe the normal reproduction of gerbils

Answer 15

-one pair inguinal nipples and one pair thoracic nipples on females
-estrous cycle 4-6 days
-post partum estrus 18 hours after delivery of pups
-gestation w/o lactation is 24-26 days, with lactation is 26-48 days (as a result of delayed implantation)
-average 7 litters/year with 3-7 pups per litter (very prolific if sexes are not separated)

Question 16

T/F: having just 1 gerbil is okay

Answer 16

True
- do well alone, do better with enrichment like running balls

Question 17

Describe the neonatal development of gerbils

Answer 17

-born hairless with eyes and ears sealed
-ears open on day 5
-hair appears on day 6
-incisors erupt on day 12-14
-eyes open on days 16-17
- weaning at 20-26 days
- sexual maturity at 9-18 weeks

Question 18

Describe the nutrition of gerbils

Answer 18

-granivorous and omnivorous
-try to avoid total seed based diets as they are low in calcium
-feed typical balanced rodent chow, but good to add variety of fruits/veggies
-food and water should be ad libitum

Question 19

What is the ideal housing for gerbils?

Answer 19

-escape free containers, cages, etc
-bedding- wood chips and corn cob is good (no colors, odors, glittering)
-need to satisfy burrowing instinct (boxes, tubes)
-temperature of 72 optimal
-use sipper tube waterers (something they cant knock over). Be sure to change water on a weekly basis

Question 20

Describe how you physically restrain gerbils

Answer 20

-grip scruff of neck (not as hard as hamster) and hold base of tail
-do not hold animal with back towards floor and do not hold by the tail alone as this may result in a degloving injury

Question 21

Where can you collect blood from a gerbil? What are some common bloodwork differences?

Answer 21

-lateral saphenous (can take 0.7-0.8 mL)
-retroorbital sinus- can be traumatic
-toe nail clip not recommended
-cardiac puncture not recommended

BW differences: lipid and cholesterol commonly higher than in other species, very short RBC lifespan (9-10 days)

Question 22

What the other name for nasal dermatitis and what causes it?

Answer 22

-sorenose
-stress induced, can be from irritation from porphyrin secretion on nose and face
-often a secondary bacterial infection with staph aureus (in most cases- but culture is still appropriate)
-results in moist dermatitis on face and on the inside of the forepaws

Question 23

What is the treatment for nasal dermatitis in gerbils?

Answer 23

-remove stressors
-clean face daily with water
-dry with soft cotton swab or cornmeal
-topical therapy (triple antibiotic ophthalmic ointment BID- less toxic than other ointments if ingested)

Question 24

Describe tyzzers disease in gerbils

Answer 24

-caused by clostridium piliforme (gram negative spore forming bacterium)
-carried subclinically in the intestinal tract
-causes poor coat conditions, weight loss, anorexia, diarrhea and/or sudden death
-high mortality, especially postpartum in young and recently weaned animals (high stress times)
-spread through fecal oral route
-no recommended treatment- can try tetracycline
-supportive care with nutrition, temp, humidity
-avoid stress
-prevent by frequent cage cleaning, reduced densities, optimal temp and humidity
-pathogen is also zoonotic to humans

Question 25

Describe salmonellosis in gerbils

Answer 25

-most common in juveniles (3-6 weeks)
-clinical signs include weight loss, rough haircoat, listlessness, dehydration and death
-often manifests as systemic disease- hepatitis and peritonitis
-antibiotic therapy is generally unrewarding thus treatment is not recommended
-pathogen is also zoonotic to humans

Question 26

Describe cystic ovaries

Answer 26

-occurs in approximately 50% of females over 1 year
-no clinical signs with small cysts
-may occur as acute abdominal swelling
-also as alopecia, anorexia, lethargy and infertility

Question 27

What are the most common neoplasias in gerbils?

Answer 27

-Reproductive tumors most common (ovarian and mammary tumors)
-adrenal tumors (adenomas and carcinomas) and skin tumors (melanomas) also occur

*higher incidence in gerbils over 2 years of age

Question 28

Describe spontaneous seizures (epilepsy) in gerbils

Answer 28

-occurs in 20% of gerbils
-some strains have 100% incidence
-tonic/clonic seizures occur between 30 seconds and 20 min in length- can range from mild and trance like to severe muscle convulsions and stiffness
-start at 2 months of age and increase in frequency up to 6 months of age
-refractory period up to 5 days post seizure
-stress related or startle induced
-treatment is not needed, often resume normal activity within minutes
-prevent by conditioning to frequent handling and often introducing to novel environments

Question 29

What are aural cholesteatomas in gerbils?

Answer 29

-keratin accumulation in inner ear
-50% of gerbils greater than 2 years of age develop these
-often push the eardrum into the ear causing permanent damage to the inner ear and vestibular problems
-otitis media may be seen in advanced cases
-can provide temporary relief with medicated eardrops
-permanent relief can be provided by careful removal of keratin plug in pieces with forceps and warm water flushes

Question 30

What parasites can affect gerbils?

Answer 30

-mites (demodex), pinworms, and tapeworms (potentially zoonotic)
-more likely to see in gerbils than hamsters as there is not as careful selection of breeding stock

Question 31

What is one of the main causes of fractures in gerbils?

Answer 31

Poor calcium levels due to excess seeds in the diet