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Spiny Mice (spiny + mouse)
Selected AbstractsTopography of Arterial Circle of the Brain in Egyptian Spiny Mouse (Acomys cahirinus, Desmarest)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2007A. Szczurkowski Summary Using stained acryl latex-injected techniques, the arterial circle of the brain in Acomys cahirinus Desmarest was studied. Results revealed an important individual variability of investigated structure. Three morphological variants were found: (1) the lack of typical arterial circle , opened in front and the back side, (2) partial opened at the back side, (3) completely closed arterial circle. This finding is opposed to many species of mammals, including rodents, and especially laboratory mouse. In our point of view, it seems to be a specific character. [source] Local variation of haemoparasites and arthropod vectors, and intestinal protozoans in spiny mice (Acomys dimidiatus) from four montane wadis in the St Katherine Protectorate, Sinai, EgyptJOURNAL OF ZOOLOGY, Issue 1 2006A. Bajer Abstract Haemoparasite infections and infestations with potential arthropod vectors were assessed in spiny mice Acomys dimidiatus from four wadis in the arid montane region of the southern Sinai in Egypt in late summer 2000. Five taxa of haemoparasites (Haemobartonella spp. 80%, Hepatozoon sp. 20.6%, Trypanosoma acomys 17.5%, Bartonella spp. 2.5% and Babesia sp. 1.9%) were recorded. Additionally, infections with two intestinal protozoa, Cryptosporidium cf. parvum and Giardia sp., were quantified, both with similar prevalence (17.0 and 17.6%, respectively). 17.9% of mice carried fleas (Parapulex chephrensis and Xenopsylla dipodilli) and 32.1% had lice (Polyplax oxyrrhyncha and Polyplax brachyrrhycha combined). Marked differences in the prevalence and abundance of infections were detected between the four wadis, particularly with respect to T. acomys, Hepatozoon sp. and fleas, which were largely aggregated in just two of the four sites (Wadis Gharaba and Tlah). In contrast, the intestinal protozoa were more common, and abundance was higher, in Wadi El Arbaein. Intrinsic factors also contributed to a variation in prevalence, with strong age-dependent increases in the prevalence and abundance of Hepatozoon sp., higher mean species richness, prevalence of Cr. cf. parvum, and abundance of Giardia sp. and Hepatozoon sp. in female mice. Haemobartonella spp. showed an age-dependent reduction in abundance and higher abundance among male mice. A weak association was found between the prevalence of T. acomys and its putative flea vector. The single extrinsic factor in the study, site of capture, was more important than the intrinsic factors in explaining variation in the prevalence and abundance of haemoparasites, intestinal protozoa and arthropod vectors. In the high mountains of southern Sinai, the parasite fauna of spiny mice is distinct in each wadi, and hence we expect the parasites to exert spatially different co-evolutionary pressures on their hosts, with a resultant variation in host life histories. [source] Differential osmoregulatory capabilities of common spiny mice (Acomys cahirinus) from adjacent microhabitatsJOURNAL OF ZOOLOGY, Issue 1 2003Uri Shanas Abstract The osmoregulatory function of common spiny mice Acomys cahirinus living on opposite slopes of the lower Nahal Oren (,Evolution Canyon') on mount Carmel, Israel, was investigated by increasing the salinity of the water source whilst maintaining a high-protein diet. The southern-facing slope (SFS) of this canyon differs from the northern-facing slope (NFS) as it receives considerably more solar radiation and consequently forms a more xeric, sparsely vegetated habitat. During the summer, mice living on the two opposite slopes significantly differed in their urine osmolality, which also increased significantly as dietary salinity increased. Offspring of wild-captured mice, born in captivity, and examined during the winter, continued to show a difference in osmoregulatory function depending on the slope of origin. However, they differed from wild-captured mice, as they did not respond to the increase in dietary salinity by increasing the concentration of their urine, but rather by increasing the volume of urine produced. This study shows that A. cahirinus occupying different microhabitats may exhibit differences in their ability to concentrate urine and thus in their ability to withstand xeric conditions. We suggest that they may also differ genetically, as offspring from the NFS and SFS retain physiological differences, but further studies will be needed to confirm this hypothesis. [source] Phylogeography of spiny mice (genus Acomys, Rodentia: Muridae) from the south-western margin of the Sahara with taxonomic implicationsBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009VIOLAINE NICOLAS The present study aims to depict the overall pattern of Acomys history in south-western Sahara. We tested the specific predictions that: (1) several mitochondrial clades can be identified and that they coincide with the described species; (2) successive phases of desert expansion and contraction during the last 3 Myr have resulted in several phases of demographic expansion and population fragmentation in Acomys; and (3) isolation-by-distance occurs. The extent of phylogeographic patterns and molecular genetic diversity (cytochrome b gene and D-loop) were addressed in a survey of 90 individuals of Acomys from 38 localities. Our phylogeographical analyses show a strong genetic structure within western Saharan Acomys, with several phylogroups displaying non-overlapping geographic distributions. Restricted gene flow with isolation-by-distance was recorded and a signal of population expansion was detected within several clades. We suggest that during arid or semi-arid paleoclimatic periods, when large sandy areas were present, Acomys was restricted to rocky massifs, whereas, in more humid periods, when savannah and/or steppe habitat prevailed, this species was able to disperse and to survive outside rocky areas because food resources were abundant. Based on a comprehensive sampling and the use of an integrative approach (i.e. combining cytogenetic, molecular and morphological data), we firmly propose that Acomys airensis should be considered as a junior synonym of Acomys chudeaui. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 29,46. [source] | ||||||||||