• Animal Systematics, Evolution and Diversity
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• v.30 no.3
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• pp.159-175
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• 2014

A taxonomic study of small mammals (Erinaceomorpha, Soricomorpha and Rodentia) was conducted in order to find out the scientific names which have been used in Korea. The synonymy of each species and taxonomical research was reviewed and confirmed in this study. The species names are rearranged based on recent studies. Among the various confused names, available names were adopted such as follows: C. shantungensis shantungensis known as Crocidura suaveolens; C. shantungensis quelpartis known as C. dsinezumi; Rattus tanezumi known as R. rattus, called black rat, roof rat and ship rat, respectively. Apodemus sylvaticus (Muridae, wood mouse) is excluded in the checklist based on indistinct previous records and ambiguous habitation on the Korean Peninsula, and neighbors. In addition, we provide a new Korean vernacular name for Myocastor coypus, called the "Nutria" in Korea. We reflect that several species are repositioned to other genera. A checklist of Korean small mammals and synonym list for each species is provided to avoid confusion of scientific names in Korea. In this study, the list of small mammals in Korea is arranged to 33 species, 20 genera, 8 families, and 3 orders.

• Applied Microscopy
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• v.43 no.4
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• pp.146-154
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• 2013

Capillaria hepatica (syn. Calodium hepatica) is a parasite found mainly in rodent liver. But, it has also been found in a wide variety of mammals, including humans. This worm is unique as it is the only nematode parasite that is embedded in the liver parenchyma of the host even during the adult stage of the life cycle. They produce eggs that elicit a marked granulomatous reaction that eventually destroys the worms. Fibrosis and lymphoplasmacytic inflammatory infiltration are often observed around adult nematodes embedded in the liver parenchyma of the host. For this reason, complete isolation of this slender worm and observation of the intact ultrastructure is very difficult. In this study, 10 intact whole worms (C. hepatica) were isolated from the liver of 3-week-old mouse after inoculation of artificially embryonated eggs collected from house rats (Rattus norvegicus). Their external structure of was observed with light and scanning electron microscopy. The length of the isolated female and male C. hepatica was approximately 69.60 mm and 36.92 mm, respectively. More detailed ultrastructure, including bacillary band, eggs and vulva in female and spicule and spicule sheath in male C. hepatica was also described.

• The Korean Journal of Ecology
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• v.11 no.1
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• pp.17-28
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• 1988

Five hundrad and eight rats were caught in Shiheung-dong and Mt. Kwan-ak from 1986 to 1987 in this survey. Ectoparasites were got from these rats and classified. The results were as follows: 9,191 mites (16 genera, 30 species), 408 fleas (4 genera, 4 species), and 521 lice (3 genera, 5 species) were observed in this survey. In the residential area, Rattus norvesicus(71.74%) was dominant species and in Mt. Kwan-ak Apodemus agrarius(93.62%). In these areas, the mites belonging to suborder Mesostigmata were dominant (Laelaps nuttli, 52.61%; Ornithonyssus bacoti, 36.05%). In Mt. Kwan-ak, family Frombiculidae belonging to suborder Prostigmata were dominant (Leptotromibidium orientalis, 31.04%; Leptotrombidium palpalis, 30.00%). In this way, it was discovered that the difference between the two regions in dominant species was noticeable. As for the hosts parasitized by mites, L. nuttalli in R. norvegicus (54.85%), L. nuttalli in R. rattus (32.90%), and L. orientalis in A. agrarius (31.27%) were dominant species, respectively. In the mites parasitizing on A. agrarius in each altitude, the species were more varied as the region was lower and the dominant species were more concentrated as it was higher.

• Animal Systematics, Evolution and Diversity
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• v.26 no.2
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• pp.99-104
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• 2010

The subfamily Murinae is a very controversial group concerning their phylogenetic relationship. Previous studies could not resolve phylogeny among four genera Apodemus, Micromys, Mus and Rattus of the Muridae. In the present study, eight rodent species resident in South Korea were collected and phylogenetically analyzed based on sequence data of five mitochondrial and nuclear DNA regions: 12S rRNA, cytochrome b gene (cyt b), cytochrome oxidase II (COII), control region of mitochondrial DNA, and a thyroglobulin (Tg) of nuclear DNA. According to the phylogeny of the concatenated data, M. musculus separated early in Murinae (ML 100%; BA 1.00 pp) and the genus Rattus grouped with the harvest mouse, M. minutes; these were separated from the genus Apodemus with relatively strong support (ML 74%; BA 0.76 pp). The Siberian chipmunk population was also examined using the five genes to obtain better resolution. The phylogeny for Korean rodents determined using the 12S rRNA, cyt b, COII and control regions discriminated the Siberian chipmunk populations from Korea, Russia, and China.

• Genomics & Informatics
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• v.3 no.2
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• pp.52-54
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• 2005

Visualization of the homology information is an important method to analyze the evolutionary and functional meanings of genes. With a database containing model genomes of Homo sapiens, Mus muculus, and Rattus norvegicus, we constructed a web­based comparative analysis tool, BioCovi, to visualize the homology information of mammalian sequences on a very large scale. The user interface has several features: it marks regions whose identity is greater than that specified, it shows or hides gaps from the result of global sequence alignment, and it inverts the graph when total identity is higher than the threshold specified.

• Korean journal of applied entomology
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• v.13 no.3 s.20
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• pp.135-139
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• 1974

A survey on rodent damage to ripening rice was conducted in Sep.-Oct. in 1973 in order to indentify the habitat type which has the greatest influence on rodent populations and damage problems. Total 109 paddies were examined in three geographical regions in central part of Korea including Kangwon and Kyoungki Provinces, which represents mountainous, coastal and rice plain lands. Sample paddies were selected according to the neighboring or surrounding habitats as farm villages, upland-crop fields, grassy river banks, forests and rice plains. Snap trapping was also conducted in each of habitats. In April, 1974, field trips were taken to representative parts of Korea visiting farmers and rural guidance officers involving more than 100 people for the information of existing local problems. The general damage of rice was considerably low in 1973 averaging $63\%$ in early ripening varieties and $0.26\%$ in standard varieties, white the average lost in 1971 was $14.2\%$ in early ripening varieties and $2.7\%$ in standard varieties. But the most of severe damages was occurred within 50 meters (practically none beyond 100m) of farm villages, caused mainly by Norway rat (Rattus rottfus Caraco) and striped field mouse (Apodemus agrarius). The examples of existing local problems confirmed that the rodent damage to field crops is closely associated with rodent populations that have survived the winter in and around farm houses and buildings.

• The Korean Journal of Ecology
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• v.27 no.3
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• pp.133-139
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• 2004

This study was conducted to clarify the preference and habitat condition of small mammals at the Hyeongsan river in Ulsan, Gyeongju, and Pohang from January 2003 to July 2003. In the study sites, total 111 individuals of Apodemus agrarius, Rattus norvegicus, and Micromys minutus were captured in study sites. The most abundant species were Apodemus agrarius, 79.2 percent, among the captured small mammals. Density of habitation was significantly higher in agricultural land than in either private house or woods. However, they were more abundant in paddy Weld area than in agricultural land. A number of captured small mammals were higher in herbaceous rather than three other vegetation types. Existent of river embankment and its type were important factors affecting the spatial distribution of the individuals. Preference of small mammals were significantly lower in revetment block area rather than in none or nature-stone mat area. There was significantly correlationship between the depth of water and the number of captured small mammals. A number of captured small mammals were clearly increased in reference to decreasing depth of water in study site, in conclusion, the following factors such as the vegetation structure, depth of water, types of land use and types of river dike could be affected the spatial distribution of small mammals in the study sites.

• Parasites, Hosts and Diseases
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• v.55 no.3
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• pp.351-355
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• 2017

Hymenolepis nana and Hymenolepis diminuta are globally widespread zoonotic cestodes. Rodents are the main reservoir host of these cestodes. Brown rats (Rattus norvegicus) are the best known and most common rats, and usually live wherever humans live, especially in less than desirable hygiene conditions. Due to the little information of the 2 hymenolepidid species in brown rats in China, the aim of this study was to understand the prevalence and genetic characterization of H. nana and H. diminuta in brown rats in Heilongjiang Province, China. Total 114 fecal samples were collected from brown rats in Heilongjiang Province. All the samples were subjected to morphological examinations by microscopy and genetic analysis by PCR amplification of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene and the internal transcribed spacer 2 (ITS2) region of the nuclear ribosomal RNA gene. In total, 6.1% (7/114) and 14.9% (17/114) of samples were positive for H. nana and H. diminuta, respectively. Among them, 7 and 3 H. nana isolates were successfully amplified and sequenced at the COX1 and ITS2 loci, respectively. No nucleotide variations were found among H. nana isolates at either of the 2 loci. Seventeen H. diminuta isolates produced 2 different COX1 sequences while 7 ITS2 sequences obtained were identical to each other. The present results of H. nana and H. diminuta infections in brown rats implied the risk of zoonotic transmission of hymenolepiasis in China. These molecular data will be helpful to deeply study intra-specific variations within Hymenolepis cestodes in the future.

• Korean Journal of Veterinary Research
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• v.39 no.5
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• pp.896-907
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• 1999

The morphometrical characteristics such as external measurements and mandible size assessment in mice and rats have to be highly heritable and sufficiently variable between strains in order to calculate a strain specific profiles. The coat color of Korean wild rats were observed and morphometric analysis of external measurements were carried out on Korean wild rats compared to laboratory strains in order to clarify the genetic characteristics of Korean wild rats and to establish background data as a domestication of Korean wild rats for new laboratory strain. Korean wild rats were captured from Chunchon and Hoengsong. 4 inbred and 1 outbred strains of rats were used in this study for the comparison of genetic characteristic of Korean wild rats. Total body length, head length, tail length, hind foot length and ear length were measured and then statistical analysis were carried out by discrimiant analysis. The coat color of Korean wild rat showed golden white in ventral portion and dark agouti in dorsal portion. Korean wild rats could be distinguished from the other laboratory strains distinctly by morphogenetical analysis. There was significant variations among Korean wild rat compared to those of the other laboratory strains of rat. This study may provide that Korean wild rats have a unique genetic characterization compared to those of other inbred strains of rats based on morphogenetical characteristics by external measurements.

• International Journal of Oral Biology
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• v.30 no.4
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• pp.125-130
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• 2005

Thrombin-induced platelet microbicidal proteins (tPMP) are antibacterial proteins released when platelets are stimulated by thrombin. It has been reported that tPMP has antibacterial activity against various bacterial species including causative agents of infective endocarditis. Most of the oral streptococci have resistance to the killing by tPMP and this fact may play an important role as a virulence factor in infective endocarditis. However, the susceptibility and resistance mechanism of oral streptococci for tPMP have not been revealed yet. In this study, the killing mechanism of tPMP for oral streptococci has been investigated. Streptococcus rattus BHT, a susceptible strain, and Streptococcus gordonii DL1, a resistant strain, have been used in this study. tPMP was isolated from platelet after stimulation with thrombin. Cell membrane depolarization was examined with 3,3'-dipropylthiodicarbocyanine iodide ($DiSC_3$), membrane potential-sensitive cyanine dye, by fluorescence spectrophotometry. The permeabilization of cell membrane by tPMP was investigated with propidium iodide (PI) by flow cytometry. tPMP susceptible S. rattus BHT showed the increase of the $DiSC_3$ fluorescence level meaning depolarization of cell membrane and increase of the uptake of PI which means permeabilization of cell membrane. However, tPMP resistant S. gordonii DLI did not show depolarization and permeabilization. These results indicate that the increasing depolarization and permeabilization of oral streptococcal cell membrane are associated with the bactericidal activity of tPMP.