|Auburn University Digital Library|
|Microlivestock - Little-Known Small Animals with a Promising Economic Future|
source ref: b17mie.htm
|Part IV : Rodents|
Many wild relatives of the guinea pig are native to South America. Some, such as the guinea pig itself, are small; others, such as the mare, are much bigger. Maras1 (Dolichotis patagonum) are as tall as terriers and, at first glance, look like dwarf antelopes or huge hares They have large ears and eyes, long legs, and short tails. They generally behave like hares or wild rabbits, but, like deer, they run with a stiff-legged gait when pursued by predators.
These strange-looking creatures are found in temperate regions in the southern half of South America. They are dry-country animals, living on the thorn-scrub, desert plains of Argentina and the stony wastes of Patagonia.
Although exceedingly shy, restless, and watchful, mares tame easily, make good pets, and are much favored by the local populace. They were introduced to France last century, and in Victorian times Europeans sometimes bred them. These big, handsome rodents, grazing in little herds, were considered an attractive addition to the lawns of country estates.
POTENTIAL AREA OF USE
Maras are best kept in their native region of southern South America. With care, however, they could be used in other areas because they are slow breeders and their population growth is easy to control.
APPEARANCE AND SIZE
At first sight, these large rodents look like some weird hybrid. They have the long ears of a hare and the tidy body and spindly legs of a small antelope. Although related to guinea pigs, they are long legged. The tail is short; the ears are long and erect.
Average-size mares weigh about 8 kg, but large ones can be 1 m long and weigh up to 16 kg.2 Females are larger than males. The coat is light in color, with grey upper parts and whitish underparts. The limbs and feet are tinged a yellowish brown. The pelage is dense, with individual hairs standing at nearly right angles to the skin. This gives a harsh texture, even though the hairs are soft and fine.
These animals can hop, walk, gallop, or run. They are extremely swift and can reach 45 km per hour over long distances. They are also accomplished jumpers, often leaping 2 m high from a standing start. The feet are compact and rather hooflike, but with sharp claws. The hind foot has three digits; the front foot has four.
The mare's range in the thorn-scrub desert and Patagonian steppe of Argentina extends from about 28ÝS to 50ÝS.
Endangered. These animals, once plentiful, are now threatened because of the introduction of the European hare, which is more successful at competing for food. In many of the eastern parts of its distribution (see map) it is now extinct.
HABITAT AND ENVIRONMENT
Maras inhabit open, dry plains and other treeless semidesert areas of coarse grass or scattered shrubs.
Maras are pure vegetarians. They feed on short grasses and herbs that are sparsely distributed between patches of dry desert scrub. Usually, they are satisfied with a few coarse weeds and the shoots of bushes. However, their overall diet consists of any available vegetation: leaves, roots, fruits, and stems.
Female mares become sexually receptive within a few hours after giving birth. The estrous cycle is 35 days, plus or minus 5 days.3 The gestation period is 77 days. Each female gives birth to 1-3 young at the mouth of the den; the pups crawl inside to safety. Newborns are well developed, and within a few hours they begin grazing vegetation. They remain in the vicinity of the den for up to 4 months.
Initially, at least, the young are nervous and easily frightened.
Maras shelter in a burrow that they either construct for themselves or "borrow" from another animal that has abandoned it. They are active during the day and spend considerable time basking in the sun. They are always alert for danger. When alarmed, they flee at high speed. The white rump patch flashes a warning to the others, who then follow this "flag."
A fundamental element of their social system is the monogamous pair bond. Certainly in captivity, and probably in the wild as well, the bond between a pair lasts for life. When breeding, 20 or more pairs may band together temporarily to share a single den for the pups.4
The animals stand on straight legs, sit on bent haunches with the forepart of the body resting on the fully extended front legs, or recline in a catlike position with the front legs folded under the chest, an unusual position for a rodent. They travel in single file, with the female usually leading. Members of a pair maintain contact by means of a low grumble. Although the long legs can quickly carry it to safety, a mare usually stops every 20-30 m and turns to peer at its pursuer.
The animals clean themselves by licking their sides and apparently by "combing" their fur with their teeth. They wipe their faces as cats do, with the inside of a foreleg.
Although the light-colored meat is said to be dry and flavorless, it is widely consumed in South America.
Maras have been successfully raised and bred in many zoos, and, as noted, have been kept as pets.
Adults make little use of any shelter; they seem fond of being out and about in all weather. As long as they have a protected burrow for the use of the pups, mare populations can thrive in severe climates.
In zoos, diets include straw, vegetables, and crushed oats. Drinking water is supplied, although the animals rarely take it if they are feeding on fresh plant materials. They like to have salt blocks, however.
In South America, one mare lived in captivity for almost 14 years; most specimens do not live beyond 10 years.
Maras are a good size for microlivestock. They have a short gestation period, and they are social and easy to maintain in groups. They can be successfully kept in pens and can be fed relatively low-quality forage. Colonies can grow to be quite large.
These animals can easily dig under the edges of cages and escape. Extra-deep foundations are needed.
Following heavy rains, care must be taken to keep them from drowning in their subterranean burrows.
If suddenly disturbed, mares can become hysterical, leaping away regardless of anything in the way, and often seriously injuring or even killing themselves as a result. They fear bodily contact.
The mare's monogamous nature in the wild is a likely limitation. But perhaps, like chinchillas, the animal will become polygamous in captivity.
The animals are sensitive to tuberculosis when kept in humid conditions.
RESEARCH AND CONSERVATION NEEDS
Research needs to increase understanding of the mare include:
- Nutritional trials;
- Husbandry experiments - measurements of growth rates, space requirements, feed needs;
- Productivity tests;
- Grazing-efficiency measurements;
- Exploration of commercial details; and
- Determination of diseases and parasites.