Spiny mouse

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Spiny mouse
Temporal range: Early Pliocene – Recent
Sinaistachelmaus.jpg
Eastern spiny mouse (Acomys dimidiatus)
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Muridae
Subfamily: Deomyinae
Genus: Acomys
I. Geoffroy, 1838
Type species
Mus cahirinus
Species

21, see text

The term spiny mouse refers to any species of rodent within the genus Acomys. [1] Similar in appearance to mice of the genus Mus , spiny mice are small mammals with bare tails which contain osteoderms, a rare feature in mammals. [2] Their coats are endowed with unusually stiff guard hairs similar to the spines of a hedgehog; this trait is the source of the common name, spiny mouse.

Contents

Despite their anatomic similarity to members of the genus Mus, genetic evidence suggests that the African spiny mice may be more closely related to gerbils than to common mice. [3]

Classification

Genus Acomys – spiny mice

As exotic pets

Desiccated spiny mouse (Acomys) corpse. Note the shorted tail, probably the result of a degloving injury. Dessicated spiny mouse (Acomys) right side.jpg
Desiccated spiny mouse (Acomys) corpse. Note the shorted tail, probably the result of a degloving injury.

Though African spiny mice originated in the deserts of Africa, they are frequently kept as exotic pets in other parts of the world, particularly Western nations such as the United States. In the pet trade, they are most commonly referred to as Egyptian spiny mice or, more simply, spiny mice. Though these animals are similar to pet mice and rats, the tail of a spiny mouse is much more delicate. Therefore, the spiny mouse should never be picked up by its tail and should be handled with care to avoid a degloving injury. Their diet is also rather hard to maintain because their bodies have odd reactions to certain foods.

Housing

Due to their desert origin, spiny mice thrive at hot temperatures and should be maintained around 27 °C (81 °F). These animals are very social and should always be housed in groups when possible. As spiny mice are prone to obesity, it is important to provide ample space and environmental enrichment to encourage exercise.

Reproduction

Gestation length is between 38 and 42 days. Litters normally consist of 2 to 3 pups, but females may have up to 6 pups in a single litter. Other females within the social group may assist in the birthing process and tend to the newborns. Pups are born with their eyes open; they will begin to leave the nesting area at about 3 days of age. Babies are weaned around 5 to 6 weeks and reach sexual maturity at about 6 to 9 weeks. A female can conceive throughout the year and may produce up to 9 litters in a year. Lifespan for spiny mice is 4 to 7 years. The mother is able to become pregnant right after birth. [4] [5]

One species of spiny mouse, the Cairo spiny mouse (A. cahirinus), was discovered to have a menstrual cycle, which would make them important as a model organism to study menstruation and reproductive disorders, as Mus musculus , the common laboratory mouse, does not menstruate. [6]

Diabetes

Captive housing of spiny mice in the mid-1960s uncovered their sensitivity to developing diabetes. [7] That is, spiny mice were kept as pets and maintained on bird food consisting of fat-rich pumpkin, sesame, and sunflower seeds. This diet was associated with obesity, glucosuria, and ketosis. Further studies, in the Institute of Biochemistry in Geneva, revealed that spiny mice manifest low insulin secretion capacity, low response to glucose, and faint first-phase insulin release, despite pancreatic islet hypertrophy and hyperplasia. Notably, they do not show the common symptom of insulin resistance. A. russatus is not known to develop symptoms of diabetes under a similar diet.

Autotomy and tissue regeneration

All studied species of spiny mice, Acomys kempi, A. percivali, A. cahirinus, A. dimidiatus, and A. russatus, are capable of autotomic release of skin upon being captured by a predator. To date, spiny mice are the only mammals known to do so. [8] They can completely regenerate the automatically released or otherwise damaged skin tissue – regrowing hair follicles, skin, sweat glands, fur and cartilage with little or no scarring. It is believed that the corresponding regeneration genes could also function in humans. [9]

In a research article published on May 16, 2017, in eLife, a team from the University of Kentucky described the role of macrophages in epimorphic regeneration. [10] The subtype of macrophages found in African spiny mice produces a different immune response than the subtype that elicits scarring.

Disease

Because spiny mice are highly prevalent throughout Africa and rodents are known to be carriers of disease, an investigation into whether spiny mice may carry disease was done in Egypt in 1912. [11] In this investigation it was determined that Acomys harbored only a tenth of the number of fleas that wild rats do and is thus of little importance of spreading disease.

Related Research Articles

<span class="mw-page-title-main">House mouse</span> Species of mammal

The house mouse is a small mammal of the order Rodentia, characteristically having a pointed snout, large rounded ears, and a long and almost hairless tail. It is one of the most abundant species of the genus Mus. Although a wild animal, the house mouse has benefited significantly from associating with human habitation to the point that truly wild populations are significantly less common than the semi-tame populations near human activity.

<span class="mw-page-title-main">Regeneration (biology)</span> Biological process of renewal, restoration, and tissue growth

In biology, regeneration is the process of renewal, restoration, and tissue growth that makes genomes, cells, organisms, and ecosystems resilient to natural fluctuations or events that cause disturbance or damage. Every species is capable of regeneration, from bacteria to humans. Regeneration can either be complete where the new tissue is the same as the lost tissue, or incomplete after which the necrotic tissue becomes fibrosis.

<span class="mw-page-title-main">Muridae</span> Family of rodents

The Muridae, or murids, are the largest family of rodents and of mammals, containing approximately 1,383 species, including many species of mice, rats, and gerbils found naturally throughout Eurasia, Africa, and Australia.

<span class="mw-page-title-main">Deomyinae</span> Subfamily of rodents

The subfamily Deomyinae consists of four genera of mouse-like rodents that were placed in the subfamilies Murinae and Dendromurinae until very recently. They are sometimes called the Acomyinae, particularly in references that antedate the discovery that the link rat, Deomys ferugineus, is part of the clade. Deomyinae is the older name and therefore has priority over Acomyinae.

<span class="mw-page-title-main">Golden spiny mouse</span> Species of rodent

The golden spiny mouse gets its name from the reddish-orange spiny fur that covers its body from head to tail. This coarse, inflexible fur is thought to protect it from predation. Aside from the golden fur that covers its head and upper parts, its flanks are yellow and its underside is pale. It has gray legs with pale feet and black soles. It is also described as having a small, but distinct white spot under each eye. It is often found in the wild missing a part or all of its tail because it is able to shed this as a defense mechanism. However, it is not known how this is done, how often it can occur, or under what conditions. It lives an average of three years in the wild. It is omnivorous and feeds on seeds, desert plants, snails, and insects. Living in desert regions, it is a xeric animal that obtains water from the plants that it eats and produces very concentrated urine in order to conserve water. A. russatus is naturally nocturnal, but adapts to being diurnal when it shares a habitat with A. cahirinus.

<i>Mus</i> (genus) Genus of rodents

The genus Mus or typical mice refers to a specific genus of muroid rodents, all typically called mice, though the term can be used for other rodents. They are the only members of the tribe Murini. However, the term mouse can also be applied to species outside of this genus.

The Western Saharan spiny mouse or Aïr spiny mouse is a species of small, insectivorous rodent in the family Muridae found arid regions of western Africa.

<span class="mw-page-title-main">Cairo spiny mouse</span> Species of rodent

The Cairo spiny mouse, also known as the common spiny mouse, Egyptian spiny mouse, or Arabian spiny mouse, is a nocturnal species of rodent in the family Muridae. It is found in Africa north of the Sahara, where its natural habitats are rocky areas and hot deserts. It is omnivorous and feeds on seeds, desert plants, snails, and insects. It is a gregarious animal and lives in small family groups. It is the first and only known rodent species that exhibit spontaneous decidualization and menstruation.

Chudeau's spiny mouse is a species of rodent in the family Muridae found in Mauritania and Morocco. Its natural habitats are rocky areas and hot deserts.

<span class="mw-page-title-main">Asia Minor spiny mouse</span> Species of rodent

The Asia Minor spiny mouse is a species of rodent in the family Muridae.

The fiery spiny mouse is a species of rodent in the family Muridae found in Kenya and Tanzania. Its natural habitats are dry savanna and rocky areas. It may be found as a commensal in human habitations.

Kemp's spiny mouse is a species of rodent in the family Muridae. It is found in Kenya, Somalia, and Tanzania. Its natural habitats are dry savanna and rocky areas. It is one of only two mammals, the other being Acomys percivali, which can shed its skin. In addition, it is known to be capable of completely regenerating damaged tissue, including hair follicles, skin, sweat glands, fur and cartilage.

<span class="mw-page-title-main">Percival's spiny mouse</span> Species of rodent

Percival's spiny mouse is a species of rodent in the family Muridae. It is found in Kenya, Somalia, South Sudan, and Uganda. Its natural habitats are dry savanna, subtropical or tropical dry shrubland, and rocky areas. It is one of two known species of mammals, the other being Acomys kempi, capable of completely regenerating damaged tissue, including hair follicles, skin, sweat glands, fur and cartilage.

The southern African spiny mouse is a species of rodent in the family Muridae. It is found in Botswana, Democratic Republic of the Congo, Malawi, Mozambique, South Africa, Tanzania, Zambia, and Zimbabwe. Its natural habitats are moist savanna and rocky areas.

<span class="mw-page-title-main">Cape spiny mouse</span> Species of rodent endemic to South Africa

The Cape spiny mouse is a murid rodent found in the Western Cape province of South Africa. They have a dorsal covering of spiny hairs with dark grey-brown colouration, and a white underbelly. The Cape spiny mouse has large eyes and ears and a scaly, nearly bald tail that is brittle and can break off readily either as a whole or in part if it is caught. Their total length is 17 cm (6.7 in), with an 8 cm (3.1 in) tail, and they typically weigh 22 g (0.78 oz).

Wilson's spiny mouse is a species of rodent in the family Muridae. It is found in Ethiopia, Kenya, Somalia, South Sudan, Tanzania, and Uganda. Its natural habitats are dry savanna, subtropical or tropical dry shrubland, and rocky areas.Molecular evidence suggests that spiny mice (Acomys) are genetically more closely related to gerbils (Gerbillinae) than they are to actual mice (Muridae) based on their murine morphology.

Flexible or opportunistic breeders mate whenever the conditions of their environment become favorable. Their ability and motivation to mate are primarily independent of day-length (photoperiod) and instead rely on cues from short-term changes in local conditions like rainfall, food abundance and temperature. Another factor is the presence of suitable breeding sites, which may only form with heavy rain or other environmental changes.

Menstruation is the shedding of the uterine lining (endometrium). It occurs on a regular basis in uninseminated sexually reproductive-age females of certain mammal species.

Rodent mite dermatitis is an often unrecognized ectoparasitosis occurring after human contact with haematophagous mesostigmatid mites that infest rodents, such as house mice, rats and hamsters. The condition is associated with the tropical rat mite, spiny rat mite and house mouse mite which opportunistically feed on humans. Rodent mites are capable of surviving for long periods without feeding and travelling long distances when seeking hosts. Cases have been reported in homes, libraries, hospitals and care homes. A similar condition, known as gamasoidosis, is caused by avian mites.

References

  1. Musser, G.G.; Carleton, M.D. (2005). "Genus Acomys". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. pp. 1194–1201. ISBN   978-0-8018-8221-0. OCLC   62265494.
  2. Maden, Malcolm; Polvadore, Trey; Polanco, Arod; Barbazuk, W. Brad; Stanley, Edward (2023-05-24). "Osteoderms in a mammal the spiny mouse Acomys and the independent evolution of dermal armor". iScience. 26 (6). Bibcode:2023iSci...26j6779M. doi:10.1016/j.isci.2023.106779. PMC   10291248 . PMID   37378333.
  3. Steppan, S.; Adkins, R.; Anderson, J. (2004). "Phylogeny and Divergence-Date Estimates of Rapid Radiations in Muroid Rodents Based on Multiple Nuclear Genes". Systematic Biology. 53 (4): 533–553. doi:10.1080/10635150490468701. PMID   15371245.
  4. "The Bristol Zoo". Archived from the original on 2006-12-06. Retrieved 2006-12-11.
  5. The Oregon Zoo
  6. Bellofiore, N.; et al. (January 1, 2017). "First evidence of a menstruating rodent: the spiny mouse (Acomys cahirinus)". American Journal of Obstetrics and Gynecology. 216 (1): 40.e1–40.e11. doi:10.1016/j.ajog.2016.07.041. PMID   27503621. S2CID   88779. originally published with the same authors as Bellofiore, N.; Ellery, S.; Mamrot, J.; Walker, D.; Temple-Smith, P.; Dickinson, H. (June 3, 2016). "First evidence of a menstruating rodent: the spiny mouse (Acomys cahirinus)". bioRxiv. 216 (1): 40.e1–40.e11. doi:10.1101/056895. PMID   27503621.
  7. Shafrir, Eleazar; Ziv, Ehud; Kalman, Rony (2006). "Nutritionally Induced Diabetes in Desert Rodents as Models of Type 2 Diabetes: Acomys cahirinus (Spiny Mice) and Psammomys obesus (Desert Gerbil)". ILAR Journal. 47 (3): 212–24. doi: 10.1093/ilar.47.3.212 . PMID   16804196.
  8. Seifert, A. W.; Kiama, S. G.; Seifert, M. G.; Goheen, J. R.; Palmer, T. M.; Maden, M. (2012). "Skin shedding and tissue regeneration in African spiny mice (Acomys)". Nature. 489 (7417): 561–565. Bibcode:2012Natur.489..561S. doi:10.1038/nature11499. PMC   3480082 . PMID   23018966.
  9. Cormier, Zoe (2012-09-26). "African spiny mice can regrow lost skin". Nature . Retrieved 2012-09-27.
  10. Simkin, Jennifer; Gawriluk, Thomas R; Gensel, John C; Seifert, Ashley W (2017-05-16). "Macrophages are necessary for epimorphic regeneration in African spiny mice". eLife. 6. doi: 10.7554/eLife.24623 . ISSN   2050-084X. PMC   5433844 . PMID   28508748.
  11. Petrie, G.F.; Todd, Ronald E.; Skander, Riad; Hilmy, Fouad (1924). "A report on plague investigations in Egypt". The Journal of Hygiene. 23 (2): 117–50. doi:10.1017/s0022172400008548. PMC   2167619 . PMID   20474833.