Animals ; China ; Hantavirus Infections ; veterinary ; Rodent Diseases ; virology

Animals ; China ; Ectoparasitic Infestations ; veterinary ; Geography ; Rats ; Rodent Diseases ; parasitology

Surveys on helminthic fauna of the nutria, Myocastor coypus, have seldom been performed in the Republic of Korea. In the present study, we describe Strongyloides myopotami (Secernentea: Strongyloididae) recovered from the small intestine of feral nutrias. Total 10 adult nutrias were captured in a wetland area in Gimhae-si (City), Gyeongsangnam-do (Province) in April 2013. They were transported to our laboratory, euthanized with ether, and necropsied. About 1,300 nematode specimens were recovered from 10 nutrias, and some of them were morphologically observed by light and scanning electron microscopies. They were 3.7-4.7 (4.0+/-0.36) mm in length, 0.03-0.04 (0.033) mm in width. The worm dimension and other morphological characters, including prominent lips of the vulva, blunted conical tail, straight type of the ovary, and 8-chambered stoma, were all consistent with S. myopotami. This nematode fauna is reported for the first time in Korea.
Animals ; Republic of Korea/epidemiology ; Rodent Diseases/epidemiology/*parasitology ; Rodentia ; Strongyloides/*isolation & purification ; Strongyloidiasis/epidemiology/parasitology/*veterinary

Animals ; Ehrlichia/isolation & purification* ; Ehrlichiosis/veterinary* ; Prevalence ; Rodent Diseases/microbiology* ; Rodentia ; Species Specificity

OBJECTIVETo understand the distribution, fauna, population structure of host animals and their parasitic fleas as well as popular dynamic of animal plague of natural plague foci in Junggar Basin.

METHODSSample materials and data of animals and vector insects were collected using ecological methods and the population structures were analyzed statistically. F1 antibody of Yersinia pestis in rodents' serum and organ suspension was detected by means of IHA while the pathogen of Y. pestis in rodents and vector insects was detected by means of aetiological detections and the isolated Y. pestis was detected using biochemical methods.

RESULTSThe small mammals which were found in Junggar Basin belonged to 17 species of 11 genera 7 families. Of them, 13 species of rodents were included whose parasitic fleas belonged to 19 species of 10 genera 8 families. The average coverage of Rhombomys opimus hole-community was 22.5% in Junggar Basin with the average density of R. opimus hole-community was 15.9/hm2 and the average rate of habitat of the hole-community was 70.2%. In the R. opimus community, the average density of rodents was 3.1/hole-community, and 34.4/hm2 in the nature plague foci. In the population structure of the hole-community of R. opimus, R. opimus accounted for 72.9% in the total captured rodents, Meriones meridianus was 24.5% while the others were 2.6%. In the nocturnal community of rodents, M. meridianus accounted for 64.0% in total captured rodents, Dipus sagitta was 15.1%, M. erythrourns was 7.5% and the others were 13.4%. In the rodents community of Junggar Basin, the rate of R. opimus with fleas was 84.9%, which was the highest, followed by M. tamariscinus, Euchoreutes naso and M. erythrourns, with the rates as 71.4%, 66.7% and 62.7% respectively. The rate of M. meridianus with fleas was 38.3%. There were 16 species of parasitic fleas in R. opimus, with the total flea index as 8.58 and the dominant species was Xenopsylla skrjabini. There were 17 and 16 kinds of fleas in M. erythrourns and M. meridianus respectively with the total flea index were 1.59 and 1.15, with dominant fleas were Nosopsyllus laeviceps and X. skrjabini. The serum and organ suspension of 3179 rodents which belonged to 12 species were detected by means of IHA, of them 174 samples were positive and the positive rate was 5.5%. There were 1356 samples of R. opimus in these materials, and 164 were positive, accounted for 12.1%. The samples of M. meridianus were 1255, with 9 positive, accounted for 0.7%. The samples of D. sagitta were 116 with 1 positive and the rate was 0.9%. The samples of other rodents were 452 but were all negative. There were in total 2975 organs collected from rodents, when detected by methods of isolated of Y. pestis. 15 strains of Y. pestis were isolated from 1243 R. opimus, and 2 strains isolated from 1230 M. meridianus. A total number of 11 647 fleas from rodents were detected by methods of isolated of Y. pestis in which 1 strain of Y. pestis was isolated from 4713 X. skrjabini, and 6 were isolated from 2101 Xenopsylla minax, 1 from 328 Xenopsylla conformis conformis and 1 from 250 Echidnophaga oschanini. Among the other 4255 fleas, none was isolated. The biochemical properties of these Y. pestis which isolated from Junggar Basin were positive of Maltose, Ejiao sugar and Glycerol, and negative of Rhamnose and Nitrogen, which were all strongly poisonous to mouse.

CONCLUSIONThe natural plague foci in Junggar Basin spread all over the whole Junggar Basin. There were animal plague cases found in 12 counties (cites) while Karamy, Bole, Jimusaer and Qitai were confirmed as plague foci counties (cities). Animals and vector insects of the foci were complicated but the ecological system was stable. R. opimus was recognized as the dominant host animal and its biochemical type belonged to the Middle Ages, suggesting that the foci was a new type of natural plague foci.

Animals ; China ; epidemiology ; Gerbillinae ; microbiology ; Mice ; Plague ; epidemiology ; microbiology ; Rodent Diseases ; epidemiology ; microbiology ; Yersinia pestis ; immunology ; pathogenicity

This study reports the first case of Capillaria hepatica infection in a nutria in Korea. Ten nutrias, captured near the Nakdong River, were submitted to our laboratory for necropsy. White-yellowish nodules were found in the liver of 1 of the nutrias at necropsy. Histologically, the lesions were granulomatous, and infiltrations of lipid-laden macrophages, eosinophils, and several multinucleated giant cells were observed. The lesions consisted of numerous eggs and necrotic hepatocytes. The eggs were lemon-shaped and had polar plugs at the ends of both long sides. The eggs were morphologically identified as those of C. hepatica. Worldwide, C. hepatica infection in nutrias is very rare. Nutrias are a kind of livestock, as well as wildlife; therefore, an epidemiological study for parasitic infections needs to be conducted.
Animals ; Capillaria/*isolation & purification ; Enoplida Infections/epidemiology/parasitology/*veterinary ; Female ; Male ; Republic of Korea/epidemiology ; Rodent Diseases/*parasitology ; Rodentia

A total of 1,498 small mammals (rodents and insectivores), including Apodemus agrarius (n = 1,366), Crocidura lasiura (54), Mus musculus (32), Micronytus fortis (28), Eothenomys regulus (9), Micronys minutes (6), and Cricetulus triton (3), were live-trapped in Gyeonggi-do (Province) (Paju-si, Pocheon-gun, and Yeoncheon-gun) near the demilitarized zone (DMZ) from December 2004 to September 2005. A. agrarius was found to be infected with 3 species of echinostomes (Echinostoma hortense, Echinostoma cinetorchis, and Euparyphium murinum), while C. lasiura was infected with 1 species (Echinochasmus japonicas) of echinostome. Other mammals were free from echinostome infections. Total 16 E. hortense were detected in 7 (0.5%) mice, 9 E. cinetorchis from 5 (0.4%), and 3 E. murinum from 2 (0.1%) out of 1.366 A. agrarius examined. E. japonicus was found only in 1 (1.9%; total 3 specimens) C. lasiura. These results demonstrate that A. agrarius and C. lasiura, inhabiting near the DMZ of Gyeonggi-do serve as the natural definitive hosts for several species of echinostomes, although their infection rates are low. This is the first record of natural infections of A. agrarius with E. cinetorchis and C. lasiura with E. japonicus in the Republic of Korea.
Animals ; Echinostoma/*isolation & purification ; Echinostomiasis/parasitology/*veterinary ; Humans ; Insectivora/*parasitology ; Korea ; Mice ; *Murinae/parasitology ; Rodent Diseases/*parasitology ; Rodentia ; Shrews/parasitology

Metagonimus yokogawai (Katsurada, 1912) Katsurada, 1912 (Trematoda: Heterophyidae) is parasitic in the small intestine of mammals including man and birds in Far Eastern Russia, Korea, Japan, China, and Taiwan. In the present study, the metacercariae and adults of M. yokogawai were redescribed to designate a neotype of this fluke together with reviews of previous studies including study histories from the first discovery to now. We particularly, attempted to review the study histories and morphological descriptions of M. yokogawai for the species validity, and compared with the morphological characteristics and life cycles of the closely related species, Metagonimus takahashii and Metagonimus miyatai. Finally, we proposed a differential key for the 8 known Metagonimus species distributed in East Asia. Metacercariae were obtained from the body muscles of sweetfish (Plecoglossus altivelis) collected in the Asahi River at Takebe-cho, Kita-ku, Okayama City, Okayama Prefecture, Japan. Adults were recovered from the small intestine of Syrian golden hamsters, to which the metacercariae had been fed 14 days before. A neotype was selected out of the present adult specimens. The Asahi River at Takebo-cho became the type locality of M. yokogawai. In conclusion, the present review shows that M. yokogawai, M. takahashii, and M. miyatai are valid and discriminated by means of morphological characteristics.
Animals ; Fish Diseases/parasitology ; Helminthiasis ; Heterophyidae/*anatomy & histology/*classification/isolation & purification ; Intestinal Diseases, Parasitic/veterinary ; Japan ; *Life Cycle Stages ; Mesocricetus/parasitology ; Microscopy ; Osmeriformes/parasitology ; Rodent Diseases/parasitology

The present study was performed to know the infection status of intestinal helminths in a most common species of field mice, Apodemus agrarius, from 2 southern regions of Korea. Total 133 and 103 mice were collected by the mouse trap in Hapcheon-gun, Gyeongsangnam-do and Gurye-gun, Jeollanam-do, respectively, from July 2005 to June 2006. The small intestine of each mouse was resected and longitudinally opened with a pair of scissors. The intestinal contents were washed with 0.85% saline until the supernatant became clear. Helminths were collected with naked eyes or under a stereomicroscope from the sediment of the intestinal content. More than 11 species of helminths (4 nematode spp., 5 trematode spp., and 2 cestode spp.) were recovered. Among these, heligmosomoid nematodes (97.5%) was the most highly and heavily infected species. As the members of trematodes, Plagiorchis muris, Brachylaima sp., Echinostoma hortense, Echinostoma cinetorchis, and unidentified echinostome larvae were found in the small intestines of 35 (14.8%), 12 (5.1%), 6 (2.5%), 1 (0.4%), and 1 (0.4%) mice respectively. Two species of tapeworms, Hymenolepis nana and Hymenolepis diminuta were also detected in 79 (33.5%) and 21 (8.9%) mice, respectively. Conclusively, heligmosomoid nematodes were the most prevalent (dominant) species among more than 11 helminth species detected, and Brachylaima sp. fluke is newly added in the list of intestinal trematodes in Korea.
Animals ; Helminthiasis/epidemiology/parasitology ; Helminths/*classification/*isolation & purification ; Intestinal Diseases, Parasitic/epidemiology/parasitology/*veterinary ; Korea/epidemiology ; Murinae/*parasitology ; Prevalence ; Rodent Diseases/*epidemiology/parasitology

Members of the genus Trichinella are small nematodes that can infect a wide range of animal hosts. However, their infectivity varies depending on the parasite and host species combination. In this study, we examined the susceptibility of 4 species of laboratory rodents, i.e., mice, rats, hamsters, and gerbils to Trichinella papuae, an emerging non-encapsulated Trichinella species. Trichinella spiralis and Trichinella pseudospiralis were also included in this study for comparison. Fifteen animals of each rodent species were infected orally with 100 muscle larvae of each Trichinella species. Intestinal worm burden was determined at day 6 and 10 post-inoculation (PI). The numbers of muscle larvae were examined at day 45 PI. The reproductive capacity index (RCI) of the 3 Trichinella species in different rodent hosts was determined. By day 6 PI, 33.2-69.6% of the inoculated larvae of the 3 Trichinella species became adult worms in the small intestines of the host animals. However, in rats, more than 96% of adult worms of all 3 Trichinella species were expelled from the gut by day 10 PI. In gerbils, only 4.8-18.1% of adult worms were expelled by day 10 PI. In accordance with the intestinal worm burden and the persistence of adults, the RCI was the highest in gerbils with values of 241.5+/-41.0 for T. papuae, 432.6+/-48 for T. pseudospiralis, and 528.6+/-20.6 for T. spiralis. Hamsters ranked second and mice ranked third in susceptibility in terms of the RCI, Rats yielded the lowest parasite RCI for all 3 Trichinella species. Gerbils may be an alternative laboratory animal for isolation and maintenance of Trichinella spp.
Animals ; *Animals, Laboratory ; Cricetinae ; *Disease Susceptibility ; Gerbillinae ; Intestines/parasitology ; Male ; Mice ; Muscles/parasitology ; Parasite Load ; Rats ; Rodent Diseases/*parasitology/pathology ; Trichinella/*growth & development ; Trichinellosis/parasitology/pathology/*veterinary