• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.63-67
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• 2014

This paper describes a new species of chigger mite (Acari: Trombiculidae), Gahrliepia cangshanensis n. sp., from rodents in southwest China. The specimens were collected from Yunnan red-backed voles, Eothenomys miletus (Thomas, 1914), and a Chinese white-bellied rat, Niviventer confucianus (Milne-Edwards, 1871) in Yunnan Province. The new species is unique mainly in its number of dorsal setae (n=21), and it has the following features: fT (formula of palpotarsus)=4B (B=branched), fp (formula of palpal seta)=B/N/N/N/B (N=naked), a broad tongue-shaped scutum with an almost straight posterior margin, and 17 PPLs (posterior posterolateral seta) with a length of 36-43 ${\mu}m$. This chigger mite may also infect other rodent hosts and may be distributed in other localities.

• Korean Journal of Veterinary Service
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• v.25 no.1
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• pp.75-86
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• 2002

Outbreaks from September 1999 to July 2000 of blackleg in 4 milking and fatting cattle farms in the vicinity of Munkyong(northwestern part of Gyeongbuk province) were investigated biochemical characteristics of isolates and were surveyed epidemiological works during the period of 2 months from August to September 2000. Clostridium chauvoei, the etiological agent of blackleg is a serious pathogen of cattle and sheep causing fever, depression and lameness with high mortality in growing phase of 6 to 18 months old mainly beef cattle. Biochemical and cultural properties of 4 isolated Cl chauvoei were identical to those of reported results and isolates were susceptible to ampicillin, bacitracin, chlorarnphenicol, cephalothin, ciprofloxacin, erythromycin, norfloxacin, penicillin, and tetracycline, while they were resistant to amikacin, colistin, gentamicin, kanamycin, neomycin, streptomycin and trimethoprim-sulfamethoxazole. In the results of epidemiological survey, outbreak farms that concentrated region of milking or fatting cattle in each sites were so close contact within a radius of about 1km that they are separated only by wire fence or shrub harrier and flies, rodents, wild cats and birds could have the chance to move around between those farms. The origin of the outbreak blackleg were uncertain, but the transmission between farms were mainly through the movement of farm personnel, vehicles which were struck the feces or manures from farm and other mechanical factors such as flies, rodents and birds furthermore occurred 4 farms were not vaccinated. In conclusion, a periodic disinfection, vaccination and quarantine prevention are ideal methods of damage reduction by blackleg.

• Development and Reproduction
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• v.8 no.2
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• pp.69-75
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• 2004

It has been known for many years that administration of estrogen, a so-called female hormone, has harmful effects on male fertility. However, studies employing transgenic mice deficient in estrogen receptors reveal substantial roles for estrogen in male fertility. The aim of this article is to review and summarize the current knowledge on the estrogen receptor localization in male reproductive organs including male germ cells of rodents. Also, informations about the mice models with disrupted estrogen signaling and associated phenotypes will be provided.

• The Korean Journal of Zoology
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• v.1 no.1
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• pp.1-6
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• 1958

A rat-fleas survey was carried out in Ducksonm and Kwangnaru areas of Seoul city from Janurary to December 1955 . In this survey, 1,204 redents were trapped alive and 740 of which being Rattus norvegicus, 457 Apodemus agrarius, 5 Eutamiias asiaticus and 2 shrewes ((crocidura rusila). On these rodents 270 fleas were collected and identified thus : Ceratopylidae : Monopsyllus anisus (Rothschild 1908) ···200 Leptosylla segnis(Schonherr, 1832)···1 Hystrichopsyllidae : Ctenophthalmus congener, Rothschild ···43 Neopsylla bidentiformis (Wagner, 1893)···11 Stenoponia sidimi Marikovsky, 1936···9 Pulcidae : Xenopsylla cheopis (Rothschild, 1903)···6 On the average 8.5% of the rodents were infestated with fleas. The infestation rate showed a marked varying degree in a year and three high incidence peaks in Spring (10.3%), Summer (11.4%-11.8%) and Winter (13.7%). The average number of fleas per rat (flea-index) was 0.22 for the whole year with a maximum of 0.41 in December and a minimum of 0.03 in February. Of all, the most prevalent species are Monopsyllus anisus (74.1%) and secondly Ctenophthalmus congener (15.9%). both species occupied 90% of all. Xenopsylla cheopis, a known vector of plague, was found very rare in our survey and only appeared in Winter. The striking lower incidence of flea-index compared with previous data (6.6 by Nagahana, 1931-1936) appears to be due to the nationwide application of DDT and BHC insecticides since 1945.

• Parasites, Hosts and Diseases
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• v.58 no.3
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• pp.301-308
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• 2020

Owing to global climate change, the global resurgence of vector-borne infectious diseases and their potential to inflict widespread casualties among human populations has emerged as a pivotal burden on public health systems. Tsutsugamushi disease (scrub typhus) in the Republic of Korea is steadily increasing and was designated as a legal communicable disease in 1994. The disease is a mite-borne acute febrile disease most commonly contracted from October to December. In this study, we tried to determine the prevalence of tsutsugamushi disease transmitted by chigger mites living on rodents and investigated their target vector diversity, abundance, and distribution to enable the mapping of hotspots for this disease in 2015. A total of 5 species belonging to 4 genera (109 mites): Leptotrombidium scutellare 60.6%, L. pallidum 28.4% Neotrombicula tamiyai 9.2%, Euschoengastia koreaensis/0.9%), and Neoschoengastia asakawa 0.9% were collected using chigger mite collecting traps mimicking human skin odor and sticky chigger traps from April to November 2015. Chigger mites causing tsutsugamushi disease in wild rodents were also collected in Hwaseong for the zoonotic surveillance of the vector. A total of 77 rodents belonging to 3 genera: Apodemus agrarius (93.5%), Crocidura lasiura (5.2%), and Micromys minutus (1.3%) were collected in April, October, and November 2015. The most common mite was L. pallidum (46.9%), followed by L. scutellare (18.6%), and L. orientale (18.0%). However, any of the chigger mite pools collected from rodent hosts was tested positive for Orientia tsutsugamushi, the pathogen of tsutsugamushi disease, in this survey.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.711-715
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• 2006

This study was conducted to clarify the characteristics of habitats and small rodent populations between remnant removed and left areas caused by different remnant treatment on forest floor in fired coniferous forest, Mt Gumbong, Samcheok, Korea, There were higher value of variables of understory coverage, snags, downed coarse woody debris (CWD) in natural restored area. Mean number of captured individuals and body weights of Apodemus peninsulae and Eothenomys regulus were more higher in remnant left area than in removed area, The differences in density and body weight of small rodents would be related with habitats between both study areas. The remove of remnant trees on the forest floor would not be good for small rodents. The more detailed and long-term researches would be needed for proper restoration in fired forest area.

• Journal of Life Science
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• v.33 no.4
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• pp.363-370
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• 2023

In order to use Cudrania tricuspidata extract for the development of health-functional food, biological changes in normal rodents, such as changes in blood constituent cells, blood lipids, and anti-inflammatory activity, were measured after the rodents had been drinking the substance for 2 weeks. A 30 mg daily dose of the extract taken for 2 weeks produced no change in body weight or renal function, and no toxicity was observed. Increased red blood cell levels and white blood cell levels were confirmed, and platelet counts tended to increase; thus, the extract seems to cause an overall increase in blood cells. In the case of blood lipids, it was confirmed that the extract-treated group exhibited an effect of improved blood-lipid levels, demonstrated through an increase in HDL-C of 21%, with a decrease in triglyceride of 27% compared to the control group. In addition, the decreases in both GOT and GPT led to improved liver function through use of the extract. Therefore, this study suggests that drinking Cudrania tricuspidata extract can have various effects, such as promoting blood cell production, improving blood lipids profile, improving liver function, and improving inflammatory action. The extract would be useful in the future in developing high-value industrial products such as functional foods and pharmaceuticals.

• Archives of Pharmacal Research
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• v.9 no.3
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• pp.175-181
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• 1986

Four technical grade organophosphate pesticides (Fenitrothion, Fenthion, Dizninon and EPN) were investigated for their effects on the murine immune function. Among the immunotoxicological assay parameters of NIEHS, humoral immune parameter and pathotoxicological indicators were examined in this study. Subchronic exposure of rodents to these pesticides resulted in marked suppression of humoral immune function and moderate histological changes of lymphoid organ any significant alterations of clinical status.

• YAKHAK HOEJI
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• v.29 no.1
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• pp.11-17
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• 1985

The behavioral effects of propranolol (60mg/kg) and metoprolol (100mg/kg) each alone and coadministered orally with cinnarizine (100mg/kg) were investigated and compared with each of betablockers alone treated group in rodents. Propranolol showed depressive effects through locomotor activity, conditioned avoidance response, rota-rod test, traction test, and analgesic effect in mice. When combined with cinnarizine and propranolol, the behavioral depressive effect of propranolol was reduced comparing with propranolol alone treated group. However, metoprolol alone or combined with cinnarizine didn't showed any behavioral depressive effect so much as propranolol.

• 한국유가공학회:학술대회논문집
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• 1996.11a
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• pp.30-34
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• 1996

Twenty seven strains of Lactobacillus acidophilus among 92 isolated from fecal contents of humans, pigs, calves, chickens, rodents and turkeys demonstrated inhibitory attributed to bacteriocin(s). The bacteriocin(s) were heat stable and nondialyzable proteinous compounds and exhibited narrow inhibitory spectra of activity. Neither hydrogen peroxide nor low pH were responsible for inhibitory action. All of the producer strains were resistant to their own bacteriocin or bacteriocin(s) produced by other strains. The bacteriocins from several strains from different host species were purified for further characterization. The bacteriocin(s) all exhibited similar characteristics.