Journal of Veterinary Medical Science
Online ISSN : 1347-7439
Print ISSN : 0916-7250
ISSN-L : 0916-7250
73 巻 , 6 号
June
選択された号の論文の25件中1~25を表示しています
Avian Pathology
Bacteriology
Clinical Pathology
  • Masahiro MORIMOTO
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 805-807
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/07
    ジャーナル フリー
    Smooth muscle cells can produce stem cell factor (SCF) in the normal state for the preservation of mast cells, but it is still unknown whether smooth muscle cells can enhance SCF production in response to the pathological stimuli. The present study showed that smooth muscle cells in mast cell-increased regions around worm cysts of intestinal nematodes significantly enhanced SCF gene expression compared with mast cell non-increased regions in same sample. SCF gene expression in mast cell non-increased regions in nematode-infected mice showed almost the same level as in non-infected control groups. These results indicate that smooth muscle cells can locally enhance SCF gene expression, and may have a role in local immunological reactions as growth factor-producing cells.
  • Masahiro MORIMOTO, Kyoko UTSUMIYA
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 849-851
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/02/03
    ジャーナル フリー
    IL-2 receptor β-chain overexpressed transgenic (Tg2Rβ) mice lack NK cells, but the development of other lymphocyte subsets and macrophages remained apparently intact. These mice also exhibit intestinal mastocytosis. Helminth infection induces various immune responses, such as mast cells, goblet cells, eosinophils and IgE, mediated by Th2 cytokines. IL-4 is also important in the regulation of resistance and susceptibility to Heligmosomoides polygyrus infection. However, there are contradictory results about the relation between resistance to H. polygyrus and intestinal mastocytosis. The present study showed that Tg2Rβ mice suppressed worm fecundity with mastocytosis without an increase of the levels of goblet cells, eosinophils and IgE compared with control mice. These results clearly indicated that mast cells have the ability for to protect against H. polygyrus infection. However, additional studies are required to evaluate protective effector mechanisms against H. polygyrus.
Ethology
  • Sato ARAI, Nobuyo OHTANI, Mitsuaki OHTA
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 747-752
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/28
    ジャーナル フリー
    Much attention has been given to the role that dogs play in the social, physical, and psychological development of children. Furthermore, dogs are now playing a new important role in animal-assisted education (AAE). However, some dogs have difficulty getting along with children. The aim of this study was to demonstrate how dogs' contact with children during and after their socialization period influenced their responses toward children. In total, 31 pet dogs were divided into three groups. Group 1 dogs had been in contact with children during the canine socialization period (between 3 and 12 weeks of age); Group 2 dogs had been in contact with children after this socialization period; Group 3 dogs seldom had contact with children. As soon as a child entered the room, the dog was presented three stimuli by the child over the course of several intervals. The dogs' responses were evaluated by analyzing behavior and heart rates. The dogs that had been in contact with children during their socialization period did not show aggressive behavior or excited behavior toward the child in our test. Moreover, their heart rates were significantly decreased even during the last stimulus, which involved the child running around the dog while calling its name. This study suggested that the dogs having contact with children during socialization period might not show inappropriate responses toward children and could be suitable for taking part in AAE.
Immunology
  • Yuko GOTO-KOSHINO, Koichi OHNO, Mayumi NAKAJIMA, Hiroyuki MOCHIZUKI, H ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 773-778
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/02/04
    ジャーナル フリー
    Macrophages play an important role in a variety of situations, including pathogen elimination, inflammation, and tissue repair. However, these cells are not fully studied in dogs, in part, due to the difficulty of efficiently isolating and culturing them in vitro. In this study, we cultured canine peripheral blood mononuclear cells (PBMCs) with 10 ng/ml of phorbol 12-myristate-13-acetate (PMA) for 5 days to obtain macrophages. A high number of round-adherent cells were obtained without the addition of any cytokine. These cells showed active phagocytic activity and a cell surface antigen profile different from dendritic cells. Our method facilitates a high yield of macrophages in a short cultivation period compared with previous studies. This method might be a powerful tool to study macrophage functions in dogs.
Laboratory Animal Science
  • Min-Kyong HYON, Euna KWON, Hyung Jun CHOI, Byeong-Cheol KANG
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 739-745
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/28
    ジャーナル フリー
    There is a need for a new liver fibrosis model of immunodeficient mice to study the effects of cell therapy on liver disease because there are not many animal models available to study the effects of cell therapy. In this study, we induced liver fibrosis using dimethylnitrosamine (DMN) in NOD/SCID mice to create an animal model for liver disease. DMN (5 mg/kg, i.p.) was injected intraperitoneally for three consecutive days per week for 6 or 8 weeks, and the mice were sacrificed at weeks 0, 4 and 8 after the last DMN injection. The 6-week DMN-treated group gradually recovered from serum biochemical changes, histopathological toxic effects and lesions in the liver at weeks 4 and 8 after the last DMN injection. However, the progression of liver fibrosis and toxic levels were maintained in the 8-week DMN-treated group at week 4 after the last DMN injection. The increases in iron and extracellular matrix (collagen) in the DMN-treated group were confirmed by Prussian blue (PB) and Masson's trichrome (MT) staining, respectively. Additionally, activation of hepatic stellate cells was observed by alpha smooth muscle actin (α-SMA) immunostaining and western blot. In conclusion, treatment of NOD/SCID mice with 5 mg/kg of DMN for 8 weeks can be used to induce an appropriate animal model of disease for liver fibrosis. This model may be useful for evaluation of the efficacy and safety of cell therapies such as human mesenchymal stem cell therapy.
  • Akihiko SUGIYAMA, Yuka FUJITA, Toshihiro KOBAYASHI, Mizuyuki RYU, Yasu ...
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 831-835
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/28
    ジャーナル フリー
    The purpose of this study was to evaluate the effect of protein malnutrition on the skin epidermis of mice. A low protein diet induced thinning of the skin epidermis, a decrease of cell proliferative activity in epidermal cells and a decrease of stratum corneum hydration. Dityrosine was immunostained in the cytoplasm of epidermal cells in the low protein diet group. Plasma advanced oxidation protein product (AOPP) levels were significantly more increased in the low protein diet group than in the control diet group. These results suggest that protein malnutrition adversely affects the structure and water barrier and reservoir functions of the skin epidermis, and these pathological changes are associated with the expressions of protein oxidation markers, dityrosine and AOPP.
Parasitology
  • Nobuhide KIDO, Yuko WADA, Maya TAKAHASHI, Chihiro KAMEGAYA, Tomoko OMI ...
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 845-847
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/31
    ジャーナル フリー
    The prevalence of Dirofilaria immitis in free-ranging raccoon dogs (Nyctereutes procyonoides viverrinus) was examined in the southeast region of Kanagawa Prefecture, Japan, using a rapid immunomigration (RIM) test kit. Between April 2007 and March 2010, we examined 108 raccoon dogs rescued and housed by the Kanazawa Zoological Garden. D. immitis infection was found in 8 (7.4%) raccoon dogs. This is the first report to reveal the prevalence of D. immitis infection in living raccoon dogs. The prevalence of the infection was lower than previously reported values obtained on postmortem examination. One reason might be that the present study included young raccoon dogs infected with immature worms. Significant high-risk areas of D. immitis infection in the raccoon dogs were not observed.
Pathology
  • Satoshi MURAKAMI, Akihiro OGAWA, Ryozo AZUMA, Takemi OHBA, Ryo MURATA
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 797-799
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/06
    ジャーナル フリー
    A microorganism isolated from an aborted sow's placenta has been proposed as a novel species, Arcanobacterium abortisuis. The lesions in the placenta were suppurative and necrotic placentitis, whereas lesions of three fetuses were suppurative bronchopneumonia. Gram and Grocott-positive organisms in these lesions were immunolabeled with anti- Arcanobacterium abortisuis antibody. This is the first case report, which showed the association of Arcanobacterium abortisuis with the aborted lesions of a pig.
  • Hiroki SAKAI, Kayoko YONEMARU, Masaaki TAKEDA, Kenta NIIMI, Mami MURAK ...
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 801-803
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/06
    ジャーナル フリー
    An 11-year-old male Labrador retriever presented with chronic oliguria. Ultrasonography findings revealed a protruding mass at the neck of the urinary bladder. A cystotomy was performed, and the mass was removed by ligation with surgical sutures. Histopathological examination revealed conspicuous foci with a variable number of ganglion cells in the tumor and abundant interwoven bundles of schwannian cells with fine fibers. The ganglion cells were positive for neuron-specific enolase and neurofilament. The schwannian cells were positive for vimentin, S-100 protein, and glial fibrillary acidic protein. Thus, according to the classification of tumor with neuronal cell differentiation, the urinary tumor was diagnosed as a ganglioneuroma.
Pharmacology
  • Takaaki IKEMOTO, Masaaki SUZUKI, Hirotaka ONOE
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 733-738
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/19
    ジャーナル フリー
    Skeletal-type neuroendocrine-specific protein like 1 (sk-NSPL1) has been demonstrated to be physiologically important in regulating the membrane translocation of glucose transporter 4 (GLUT4) in skeletal muscles. We investigated the levels of phosphorylation in proteins that are thought to be involved in exercise in wild-type and sk-NSPL1-deficient muscles with specific antibodies and phosphate-metal affinity chromatography resin (p-resin). In both normal skeletal muscle and sk-NSPL1-deficient muscle, adenosine monophosphate (AMP)-dependent kinase (AMPK) and acetyl-CoA carboxylase (ACC) were phosphorylated and adsorbed onto p-resin at high levels after exercise. On the other hand, the effect of 5-aminoimidazole-4-carboxyamide ribonucleoside (AICAR), which is an activator of AMPK, in blood glucose was greatly diminished in mutant mice. P-resin adsorbed sk-NSPL1 in the membrane fraction from wild-type muscle after exercise and AICAR administration. Isolated sk-NSPL1 from wild-type also had increased adsorption onto p-resin after treatment with Ca2+ and adenosine triphosphate (ATP). After long-term incubation of sk-NSPL1-containing membrane without ATP, sk-NSPL1 adsorption onto anion-exchange resin was drastically reduced. These results suggest that the function of sk-NSPL1 is regulated by a [Ca2+]i- and AMPK-mediated pathway under exercise, and support the hypothesis that sk-NSPL1 is an important factor in the downstream of the exercise-dependent pathway in GLUT4 translocation.
  • Elias GEBRU, Seung-Jin LEE, Jong-Choon KIM, Seung-Chun PARK
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 817-820
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/12
    ジャーナル フリー
    The objective of this study was to analyze the relationship between pharmacokinetic parameters and body weight (W) for orbifloxacin using reported pharmacokinetic data. The parameters of interest: clearance (Cl), volume of distribution at steady state (Vss) and elimination half-life were correlated across nine mammal species, including cattle, dog, rat, rabbit, goat, camel, horse, cat and sheep as a function of W using the conventional allometric equation Y = aWb, where Y is the pharmacokinetic parameter, W is the body weight, a is the allometric coefficient (intercept) and b is the exponent that describes the relationship between the pharmacokinetic parameter and W. Our estimates (Cl=4.40 W1.03; Vss=1.10W1.05) indicated that the increase in these parameters with W approximates a linear power relationship with slopes being very close to one. Overall, the results of this study indicated that it is possible to use allometry to predict pharmacokinetic variables of orbifloxacin based on W of mammal species.
Physiology
  • Eui-Man JUNG, Ji-Hye KIM, Hyun YANG, Sang-Hwan HYUN, Kyung-Chul CHOI, ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 711-716
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/07
    ジャーナル フリー
    Transient receptor potential vanilloid 6 (TRPV6) is a major calcium channel located in the apical and basolateral membranes of cells and distributed widely in many other organs, especially the exocrine tissues, intestine and uterus. Uterine TRPV6 is affected by sex steroid hormonal changes during the estrous cycle and pregnancy. To determine whether sex steroid hormones influence the expression of TRPV6 in other tissues, we further examined TRPV6 mRNA expression in the duodenum and kidney by reverse transcriptase and real-time PCRs and its protein levels by Western blot analysis and immunohistochemistry (IHC). Immature rats were injected with 17 β-estradiol (E2; 40 μg/kg) and/or progesterone (P4; 4 mg/kg) for three days. Treatment with a mixture of E2 and P4 (E2/P4) increased TRPV6 expression in the duodenum, and this increase was maintained when the rats were treated with receptor antagonists of estrogen (ICI 182,780; 10 mg/kg) or progesterone (RU 486; 10 mg/kg) 30 min before E2/P4 injection. However, no difference was observed in renal TRPV6 protein levels following the treatment with sex steroid hormones and/or antagonists by Western blot analysis and IHC. These results suggest that duodenal TRPV6 expression may be induced by E2 combined with P4, whereas the renal TRPV6 level is unaffected by these steroids.
  • Kohei AMAKASU, Katsushi SUZUKI, Kentaro KATAYAMA, Hiroetsu SUZUKI
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 787-795
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/02/07
    ジャーナル フリー
    Affected rats of the unilateral urogenital anomalies (UUA) strain show renal agenesis restricted to the left side. To determine whether unilateral renal agenesis is a risk factor for the progression of renal insufficiency, we studied age-related pathophysiological alterations in affected rats. Although body growth and food intake were normal, polydipsia and polyuria with low specific gravity were present at 10 weeks and deteriorated further with age. Blood hemoglobin concentrations were normal, though there was slight erythropenia with increased MCV and MCH. Although hypoalbuminemia, hypercholesterolemia, azotemia, and hypermagnesemia were manifested after age 20 weeks, neither hyperphosphatemia nor hypocalcemia was observed. Plasma Cre and UN concentrations gradually increased with age. Cre clearance was almost normal, whereas fractional UN excretion was consistently lower than normal. Proteinuria increased with age, and albumin was the major leakage protein. In addition to cortical lesions, dilated tubules, cast formation, and interstitial fibrosis were observed in the renal medulla of 50 week-old affected rats. Renal weight was increased 1.7-fold and glomerular number 1.2-fold compared with normal rats. These findings show that the remaining kidney in UUA rats is involved not only in compensatory reactions but experiences pathophysiological alterations associated with progressive renal insufficiency.
Public Health
  • Sung-Il KANG, Eun Jeong HEO, Donghee CHO, Jong Wan KIM, Ji-Yeon KIM, S ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 779-786
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/02/07
    ジャーナル フリー
    The multiple-locus VNTR analysis (MLVA) assay is a method frequently employed as a molecular epidemiological tool for Brucella genetic fingerprinting. The purpose of this study was to assess the genotyping of 77 B. canis isolates from 14 different dog breeding farms in Korea by the MLVA assay and to compare the epidemiological relationships between the Korean isolates and foreign ones. Simpson's diversity index for 17 loci showed a range from 0 to 0.846 in 77 B. canis isolates. B. canis isolates in Korea were observed to have high genetic diversity at the most variable loci and were divided into 30 distinct genotypes by phylogenetic analysis. Some B. canis isolates were closely related to previously typed isolates in other countries. The MLVA assay can be helpful to analyze the epidemiological correlation of B. canis isolates in domestic pet animals and to track the geographic origin by comparing the genetic patterns with foreign isolates. Therefore, the MLVA assay will be useful as a tool for control and preventive measures of canine brucellosis.
Surgery
  • Takahiro TAODA, Yasushi HARA, Hiroyuki MASUDA, Takahiro TESHIMA, Yoshi ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 725-731
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/11
    ジャーナル フリー
    The displacement and signal intensity (SI) of the pituitary posterior lobe were evaluated on T1 weighted magnetic resonance (MR) images in 28 dogs with pituitary dependent hyperadrenocorticism (PDH). Compared with normal dogs, the posterior lobe was displaced dorsally in the pituitary of the PDH dogs. Correlation between the pituitary height/brain area (P/B) ratio and the displacement of the posterior lobe in the PDH dogs suggests that dorsal displacement of the posterior lobe increases in accordance with enlargement of the pituitary. As to the SI of the posterior lobe, the PDH dogs showed significantly lower SI in comparison to the normal dogs. Taken together, these results suggest that assessment of the displacement and SI of the posterior lobe of the pituitary on T1-weighted MR images is useful for the diagnosis of pituitary adenoma. In pituitary microadenoma that presents no apparent tumorigenesis on MRI, evaluation of these values may be useful for diagnosis and selection of an appropriate therapy.
Theriogenology
  • Shihua YANG, Shuhuang PING, Wei SI, Xiechao HE, Xinyi WANG, Yongqing L ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 717-723
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/07
    ジャーナル フリー
    Ethylene glycol (EG) has been speculated to be the most appropriate penetrating cryoprotectant for cryopreservation of rhesus macaque sperm due to its higher permeability coefficient. The present study aimed to determine the optimal EG concentration, freezing rate and holding time in liquid nitrogen (LN2) vapor for rhesus sperm cryopreservation. Among six tested EG concentrations (0, 0.18, 0.35, 0.7, 1.4 and 2.1 M), 0.7 M EG showed the most effective cryoprotection (P<0.05). Sperm frozen with 0.7 M EG at -183°C/min showed higher post-thaw motility than sperm frozen at -10, -67 or -435°C/min (P<0.05). Sperm frozen in LN2 vapor at -183°C/min with 0.7 M EG and a holding time of 10 min showed higher post-thaw motility compared with a holding time of 5 or 15 min (P<0.05). The function of sperm cryopreserved at the optimized EG concentration, freezing rate and holding time was further evaluated by in vitro fertilization. Of the 36 oocytes collected from gonadotropin-stimulated rhesus macaques, 61.1% were fertilized, and 61.1, 44.4 and 36.1% of the oocytes developed to 2 cells, morulae and blastocysts, respectively. Our findings provide an alternative penetrating cryoprotectant and optimal protocol for genetic preservation purposes in this important species.
  • Shin-ichi HAYAMA, Sachie NAKIRI, Fumiharu KONNO
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 809-812
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/11
    ジャーナル フリー
    This study is the first to determine the conception dates of specific individuals and estimate the pregnancy rate of a wild population in Japanese monkeys. The conception dates estimated from the embryonic ages of 37 fetuses were distributed over 128 days between September 17 and January 23, with a mean conception date of November 19 (SD=29.2 days). A comparison of the mean conception dates among age groups showed a significantly delayed conception in the subadult animals (aged 4 to 5 years; December 5, n=8) than in the adult animals (aged 6 or more years; November 15, n=29; P<0.03). The mean pregnancy rate among animals aged 4 years or more in this local population was estimated to be 48.5% (32/66).
  • Mari TOYONAGA, Miki MORITA, Tatsuya HORI, Toshihiko TSUTSUI
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 827-829
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/26
    ジャーナル フリー
    Glycoproteins (GPs) are known to be involved in the phenomenon of sperm maturation and capacitation. In the present study, we investigated the attachment of GPs on sperm cell membrane during the process of feline sperm maturation from testicular sperm to ejaculated sperm by using 8 FITC-labeled lectins. The results showed that 3 types of GPs were presented on testicular sperm and 7 on caput epididymal sperm. Corpus and cauda epididymal sperm and ejaculated sperm had GPs detected by 8 FITC-labeled lectins used in the present study. This study demonstrates the part of the characteristic of GPs that are present on the feline sperm cell membrane during the process of sperm maturation.
Toxicology
Virology
  • Hiromi YOSHIDA, Yoshihiro SAKODA, Mayumi ENDO, Masayuki MOTOSHIMA, Fum ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 753-758
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/28
    ジャーナル フリー
    Migratory water birds are a natural reservoir for influenza A viruses. Viruses replicate in the intestines of ducks and are shed with the fecal materials. Virus isolation from collected fecal materials, therefore, is an integral part of the surveillance of avian influenza in water birds. In the present study, reverse transcription loop-mediated isothermal amplification (RT-LAMP) was assessed for its usefulness in detecting the RNA of influenza A viruses in fecal materials. It was found that, RT-LAMP specifically and sensitively detects the matrix gene of influenza A viruses. Influenza A viruses were isolated from the fecal materials in which viral RNA were detected by RT-LAMP in 35 min. The present findings indicate that RT-LAMP is useful as a high throughput screening method for field samples prior to virus isolation, allowing the processing of hundreds of samples per day.
  • Nobuyuki MOCHIZUKI, Yuki KOBAYASHI, Go SATO, Shinji HIRANO, Takuya ITO ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 759-766
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/02/02
    ジャーナル フリー
    The complete genome sequences of two Brazilian wild-type rabies viruses (RABV), a BR-DR1 isolate from a haematophagous bat (Desmodus rotundus) and a BR-AL1 isolate from a frugivorous bat (Artibeus lituratus), were determined. The genomes of the BR-DR1 and BR-AL1 had 11,923 and 11,922 nt, respectively, and both encoded the five standard genes of rhabdoviruses. The complete nucleotide sequence identity between the BR-DR1 and BR-AL1 isolates was 97%. The BR-DR1 and BR-AL1 isolates had some conserved functional sites revealed by the fixed isolates, whereas both isolates had unique amino acid substitutions in the antigenic region IV of the nucleocapsid gene. Therefore, it is speculated that both isolates were nearly identical in virologic character. According to our phylogenetic analysis based on the complete genomes, both isolates belonged to genotype 1, and to the previously defined "vampire bat-related RABV lineage" which consisted of mainly D. rotundus- and A. lituratus- isolates; however, a branch pattern with high bootstrap values suggested that BR-DR1 was more closely related to the 9001FRA isolate, which was collected from a dog bitten by a bat in French Guiana, than to BR-AL1. This result suggests that the vampire bat-related RABV lineage includes Brazilian vampire bat and Brazilian frugivorous bat RABV and is further divided into Brazilian vampire bat and Brazilian frugivorous bat RABV sub-lineages. The phylogenetic analysis based on the complete genomes was valuable in discriminating among very closely related isolates.
  • Kosuke SODA, Ming-Chu CHENG, Hiromi YOSHIDA, Mayumi ENDO, Shu-Hwae LEE ...
    原稿種別: FULL PAPER
    2011 年 73 巻 6 号 p. 767-772
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/02/03
    ジャーナル フリー
    H5N2 viruses were isolated from cloacal swab samples of apparently healthy chickens in Taiwan in 2003 and 2008 during surveillance of avian influenza. Each of the viruses was eradicated by stamping out. The official diagnosis report indicated that the Intravenous Pathogenicity Indexes (IVPIs) of the isolates were 0.00 and 0.89, respectively, indicating that these were low pathogenic strains, although the hemagglutinin of the strain isolated in 2008 (Taiwan08) had multibasic amino acid residues at the cleavage site (PQRKKR/G). In the present study, these H5N2 viruses were assessed for their intravenous and intranasal pathogenicity for chickens. It was examined whether Taiwan08 acquires pathogenicity through consecutive passages in chickens. Intravenous pathogenicity of Taiwan08 depended upon the age of the chickens used for the IVPI test; all of the eight-week-old chickens intravenously inoculated with Taiwan08 showed clinical signs but survived for ten days post inoculation (IVPI=0.68), whereas all the six-week-old chickens died (IVPI=1.86). Taiwan08-P8, which were passaged in chickens for eight times, killed all the eight-week-old chickens (IVPI=2.36). The four-week-old chickens died after intranasal inoculation of Taiwan08-P8, indicating that Taiwan08 must have become highly pathogenic during circulation in chicken flocks. These results emphasize the importance of a stamping out policy for avian influenza even if the IVPI of the causal virus is low.
  • Masayuki SHIMOJIMA, Yumiko NAGAO, Hiroshi SHIMODA, Seiji TAMARU, Takas ...
    原稿種別: NOTE
    2011 年 73 巻 6 号 p. 813-816
    発行日: 2011年
    公開日: 2011/07/05
    [早期公開] 公開日: 2011/01/11
    ジャーナル フリー
    In the past 25 years, there has been only one case of Japanese encephalitis in horses in Japan. We determined the full genome sequence of the Japanese encephalitis virus (JEV) strain JEV/eq/Tottori/2003 isolated from an afflicted horse and also analyzed its virulence in mice. The sequence analysis showed that the genome of JEV/eq/Tottori/2003 is similar to that of genotype I, a dominant genotype of JEV presently circulating in Japan. Its neurovirulence, but not neuroinvasiveness, was still as high as it was for genotype III, thus indicating the necessity for continuation of a vaccination program of horses against JEV.
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