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HOUSING AND CARE
Natural habitat: arid (乾燥) and semi-arid regions of Africa, Asia, and Middle East.
Captivity: Temperature: 70-720 F
Humidity: 40%
Light: 12 hours/day
Caging: Polyethylene cages with bedding (not pine)
need less frequent cleaning than other rodents.
Natural diet: seeds, leaves, stems, and roots.
Captivity: commercial rat or mouse chow 5 gm/day for ave. sized
gerbil water-ave. 4 ml/day.
HANDLING
Pick up from the base of the tail.
COMMON DISEASES
Staphylococcal dermatitis
Facial dermatitis
Tyzzer's disease-- most susceptible animal；used for sentinels
Salmonella-- no carrier state
Neoplasia-- adrenal, ovarian, cutaneous
Leptospirosis
Ovarian cysts
Chronic interstitial nephritis
Epileptiform seizures
Dihydrostreptomycin toxicity
USES IN RESEARCH
Parasite research-- especially filarids
Auditory research
Infectious diseases
Dental caries: induced by cariogenic diet, periodontal DC
Lead poisoning：lead nephropathy, nephron accumulate 4-6 x leade as rats
Renal studies
Thermoregulatory function
MISCELLANEOUS
Anesthesia Ketamine- 44 mg/kg IM
Na pentobarbital 60 mg/kg IP
Methoxyflurane
Prohibited from use in California unless obtain permit issued by
the California Fish and Game Department.
RERERENCES
1. Holmes, D.D. 1985. The mongolian gerbil in biomedical research.
Lab. Anim. 14(3):23-38.
2. Oufaras, S.H.Barr'e, J.L.Rouanet, and J.Chatonnet. 1987.
Adaptation to extreme ambient temperatures in cold-acclimated
gerbil and mice. Am.J.Physiol. 253(1 pt 2):39-45.
3. Schoeb,T.R. 1988. Class notes. Diseases of Gerbils. PAT 707
University of Alabama at Birmingham. pp.1-5.
4. Wightman, S.R., P.C. Mann,and J.E. Wagner. 1980.
Dihydrostreptomycin toxicity in the Mongolian gerbil,Meriones
Unquiculatus. Lab. Anim. Sci. 30(1):71-75.
MONGOLIAN GERBIL
Meriones uniguiculatus
Background
The Mongolian gerbil or Jird is native to Northern African,
Central Asia, and Asia Minor. It lives in clay and sandy deserts,
bush country, arid steppes, low plains and cultivated lands, grass
lands, and mountain valleys. Externally the gerbil is quite rat-like
with narrow, well developed ears, a tail length which approximates
that of the head and body, upper incisors with narrow groove on the
anterior surface, and slightly elongated hind legs for leaping. The
claws are very strong for burrowing in fairly soft soil to form their
homes. These burrows which are relatively simple in structure frequently
have several exits. They have very dense fur which is fairly long and
soft. The covering of the tail is short near the base and progressively
longer towards the tip so that the tip is sightly bushy and has a slight
crest. Coloration of the upper parts varies from pale yellow to sandy.
The sides of the body due to the absence of black tip hairs. The under
parts including the hands and feet are white, buffy, or pale grey.
These animals often live close together, thus forming a colony which
is usually partially sheltered by shrubs or other vegetation. The diet
consists of seed, leaves, bulbs, stems or roots which, at least in
some cases, are stored in the burrows. They are reported to hibernate.
The Mongolian Gerbil in Mongolia and Northern China has a high capacity
for temperature regulation in comparison with many desert rodents.
The Mongolian Gerbil was introduced in the United States by Dr. Victor
Schwentker, in 1954. Its unique physiological characteristics and many
susceptabilities have proved an essential new tool for research.
Physiological and Anatomical Characteristics
Basic physiological and anatomical characteristics of the Mongolian
Gerbil are as follow:
Adult male weight = 80 to 90 grams
Adult female weight = 70 to 80 grams
Birth weight = 2.5 to 3.5 grams
Female breeding age = 9 to 12 weeks
Male breeding age = 10 to 12 weeks
Estrous cycle = 4 to 6 days
Gestation range = 24 to 26 days
Weaning age = 21 days (or to weight of 12 to 15 grams)
Litter size = 4 to 12 (average about five)
Posportum estrus with pair breeding
Daily water requirement: approximately 5 grams
Recommended temperature range for gerbil is: 60 to 80 F with a
humity of about 40 %.
Light requirement of 12 hours days and 12 hours dark
Respiration rate = 90 to 250 (ave. 150)
Heart rate of approximately 350 to 700 (ave. around 600)
Body temperature for adult gerbils is approximately 38 C
Handling Techniques
Gerbils are certainly the most pleasant of all laboratory mammals
to handle even for the novice. When their cage is open, their curiosity
compels them to come to the opening where they may be picked up readily.
They can be scooped up in one's palm where they usually remain without
restraint. Gerbils learn rapidly, ten times faster than rats in some
situations. After a few handlings they become amenable and even cooperative.
For rapid handling, the best method is to pick them up by the tail
near the base; the skin and bones near the tip are quite fragile. To
prevent falls in moving the gerbil from one location to another, the
free hand can be used to support the animal's body. If the gerbil escapes
on the floor there is little cause for concern. Usually it will satisfy
its curiosity by exploring rather than hiding; often it can be approached
and recaptured easily. If it enters an inaccessable place it will usually
come out shortly without hiding.
A one hand restraint similar to that used in mice and rats can be
used for gerbils for IP injections in either lower quadrant of the
abdomen. Subcutaneous injections may be given under a pinch of skin
over the neck and shoulder area.
Pregnant or lactating females and the neonates can be handled safely
at any time. Young gerbils near weaning age sometimes jump when startled
and precautions should be taken to prevent escapes or falls. Injections
in the tail veins can be done, but this requires considerable skill.
Likewise tail snipping may be impratical
because of the small vessel size. Other bleeding sites include the
heart and the madial canthus of the eye. These techniques can be repeated
at 3 to 4 day intervals, depending on the health of the animal and
the amount of blood required.
Experimental Uses
Like most desert animals, gerbils have a unique metabolism and a
considerable capability for dehydration rehydration. In nature they
require no water except that matabolized from their food. In a laboratory,
however, the higher protein content and lower moisture content of the
pelleted feed dictate a higher water intake. Even so they can be maintained
without drinking water if fresh clean greens such as lettuce or cabbage
are provided several times a week. This charateristic is most useful
in many research studies.
The gerbil's unique physiology and many suseptabilities have increased
its usefulness in many research fields. Yet the exploration of its
potential utility has just begun. Its intermediate size, ease of handling,
and natural curiosity make it a valuable research tool for studies
involving multiple manipulations.
Like any recently introduced species, gerbils, of the same sex and
age may show considerable weight variation. The differential is being
narrowed by selective breeding, but at this stage it is not to the
point where uniformity can be achieved. Gerbils are generally very
healthy and hardy, presenting few complications with disease. To date
no endemic diseases have been found and unexplained deaths are rare.
This condition often occurs when wild animals are brought into the
laboratory. For example, golden hamsters were free of disease when
they were introduced from Syria but now have several identifiable disease.
This may occur with the gerbil also. Its prevention or delay depends
upon the effectiveness and sanitation employed.
Another unique characteristic of the gerbil is that when handled
or subjected or environmental changes, some gerbils may undergo epileptic
type seizures of mild to severe nature; recovery is rapid and apparently
complete. Although the origin seems to be geneticaly determined the
actual cause is uncertain.
The gerbil has been used in nutritional and toxocology studies as
well as studies involving behavior and radiation research. Because
of its unique metabolism it is utilized in studies involving water
intake and kidney output.
Strains and Sources
At the present time there are no inbred strains of gerbils. The genetic
diversity from the original introduced animals has not been great due
to the shortness of time involved. The primary source of
Mongolian gerbils in the United States is the Tumblebrook Farm Inc.,
of Westbrookfield, Mass. Other individual suppliers of Mongolian gerbils
do exist but care must be taken to investigate fully the supplier's
reputation in the research field before utilization of these animals.
It is recommended that once an individual supplier is selected and
a study initiated, the researcher should resist changing suppliers
until the individual study is completed. Although several suppliers
may offer the same animal, the variability between one supplier and
another can be great. It cannot be over emphasized that extreme care
and caution must be taken when selecting a source of animals to be
used for scientific research protocols.
The Mongolian gerbils is not specifically covered in the rules and
regulations under the various public laws administered by the U.S.
Department of Agriculture. Therefore, no specific federal permits or
licenses are required to produce and handle these animals. However,
this species is currently prohibited from use in California unless
the user has a current and valid permit from the California Fish and Game Department. | 
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