Severe nonpurulent encephalitis with mortality and feather lesions in call ducks (Anas platyrhyncha var. domestica) inoculated intravenously with H5N1 highly pathogenic avian influenza virus     

Yamamoto Y  Nakamura K  Kitagawa K  Ikenaga N  Yamada M  Mase M  Narita M 《Avian diseases》2007,51(1):52-57

One-day-old, 2-wk-old, and 4-wk-old call ducks (Anas platyrhyncha var. domestica) inoculated intravenously with the H5N1 highly pathogenic avian influenza virus A/chicken/Yamaguchi/7/2004 isolate (Ck/Yama/7/04) were examined clinically, pathologically, and virologically. Clinically, the birds exhibited mild-to-severe neurologic signs and corneal opacity. All birds in the 1-day-old group and one bird in the 4-wk-old group died within 4 days after the virus inoculation. Histologic changes were characterized by severe nonpurulent encephalitis and necrotic lesions of feather epithelium on day 3 postinoculation (PI) or later. Focal necrosis of myocardial cells, pancreatic acinar cells, skeletal myocytes, and corneal epithelial cells was observed. Viral antigens were detected in association with necrotic changes. Viruses were isolated from all examined organs including the skin with many feathers. Serum antibody against the virus was detected in all surviving birds on day 10 PI by hemagglutination-inhibition tests. These results suggest that Ck/Yama/7/04 has a pathogenicity that causes neurologic sign, nonpurulent encephalitis with mortality, and feather lesions for call ducks. Feather lesions with viral antigens and the virus isolation from the skin suggest that Ck/Yama/ 7/04 has a predilection for feathers in call ducks.  相似文献   

Antihyaluronidase action of ellagic acid effectively prevents polyspermy as a result of suppression of the acrosome reaction induced by sperm-zona interaction during in vitro fertilization of porcine oocytes     

Tokeshi I  Yoshimoto T  Muto N  Nakamura S  Ashizawa K  Nakada T  Tatemoto H 《The Journal of reproduction and development》2007,53(4):755-764

The present study was conducted to examine the effects of three tannin relatives (tannic acid, TA; gallic acid, GA; and ellagic acid, EA) on antihyaluronidase and reactive oxygen species (ROS) scavenging activity, in vitro fertilization (IVF) parameters, and the acrosome reaction (AR) induced by sperm-zona interaction. Among the three tannin relatives, TA and EA showed the strongest potency for blocking the hyaluronidase activity of boar sperm, with concentration-dependent inhibition over the range of 2-10 microg/ml. In contrast, ROSs were effectively scavenged by TA and GA, but not EA. When cumulus-free oocytes were inseminated in IVF medium containing 5 microg/ml of the tannin relatives, polyspermy was significantly reduced by TA and EA (32 and 29%, respectively) compared with oocytes treated with or without GA (51 and 69%, respectively) under conditions that maintained a high sperm penetration rate (P<0.05). Interestingly, induction of the AR by treatment of preincubated sperm with progesterone was blocked by TA and GA as a result of their higher levels of ROS scavenging activity, while EA, which possessed weak ROS scavenging activity, did not disturb induction of the AR with progesterone. However, the incidence of AR induced by sperm-zona interaction was significantly decreased by the strong antihyaluronidase actions of TA and EA compared with that in the absence of these compounds. Treatment with the compounds caused neither a protective proteolytic modification of the zona pellucida matrix before fertilization nor a reduction in acrosomal proteolytic activity or the number of zona-bound sperm. These findings suggest that the antihyaluronidase action of EA effectively prevents polyspermy by suppression of AR functionality induced by sperm-zona interaction and that hyaluronidase intervention is therefore required during porcine IVF.  相似文献   

Census and effective population sizes of white‐spotted charr (Salvelinus leucomaenis) in a fragmented landscape          下载免费PDF全文

Shoichiro Yamamoto  Hitoshi Kubota  Koh Hasegawa  Tomoyuki Nakamura 《Ecology of Freshwater Fish》2016,25(4):612-621

Several habitat models have been proposed to predict population size for stream fishes and to guide habitat assessment and monitoring techniques. However, most models do not incorporate the potential advantage of molecular genetic markers. We conducted a field survey and microsatellite DNA analyses to quantify the relationships among genetic diversity, census/effective population size and habitat variables in fragmented populations of white‐spotted charr (Salvelinus leucomaenis). The census population size significantly increased with the stream length, the number of pools and a pool‐riffle sequence index, a proxy for channel‐unit habitat type complexity within reaches. Population density was correlated with the pool‐riffle sequence index only. Genetic diversity and effective population size were not correlated with the habitat variables or census population size. There was a lack of isolation‐by‐distance population structure in the studied populations. Our results suggest that stream length and the number of pools within reaches associated with habitat complexity are the habitat variables that explain the majority of variation in population size of white‐spotted charr. Our findings provide further evidence that census population size per se is a poor indicator of the inclusive genetic diversity within populations in a fragmented landscape.  相似文献   

Expression patterns of the erbB subfamily mRNA in canine benign and malignant mammary tumors     

Matsuyama S  Nakamura M  Yonezawa K  Shimada T  Ohashi F  Takamori Y  Kubo K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(9):949-954

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Arthroderma benhamiae infection in a rabbit   总被引：3，自引：0，他引：3  

Saito K  Kano R  Nakamura Y  Watanabe S  Hasegawa A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(8):929-931

The isolate from the rabbit with dermatophytosis which was transmitted to the owners was proved to be Arthroderma benhamiae (-) by mating experiments as well as by chitin synthase 1 (CHSI) gene analysis.  相似文献   

Proportions of melanocyte stimulating hormone-immunoreactive cells in the adenohypophysis of Silky fowl and hyperpigmentation-free cockerels     

Shotaro NISHIMURA  Hitomi SHIMODA  Ichiro OSHIMA  Yoshitaka ONO  Kaoru OKANO  Akira ISHIBASHI  Shoji TABATA  Hisao IWAMOTO 《Animal Science Journal》2005,76(6):575-579

Alpha‐melanocyte stimulating hormone (α‐MSH) is one of the main regulators for melanocytes, and the adenohypophysis is one of the major tissues for the synthesis of this hormone. The Silky fowl is a characteristic breed of chicken with hyperpigmentation throughout the body. The involvement of the adenohypophysis in the hyperpigmentation of this breed is not known. In the present study, the proportion of melanocyte stimulating hormone‐immunopositive cells (MSH cells) in the adenohypophysis was immunocytochemically compared between Silky, Red Cornish × New Hampshire (RN) crossbred and Japanese bantam cockerels at 15 weeks of age. After the body and gland were weighed, the adenohypophyseal cells were enzymatically dispersed and immunostained for α‐MSH, and the immunopositive MSH cells were counted. The weights of the body and adenohypophysis were heaviest in the RN crossbred, followed by the Silky and lightest in the bantam cockerels. In contrast, the ratio between adenohypophysis and bodyweight was much larger in the Silky and the bantam than in the RN crossbreed (P < 0.05). The population of MSH cells in the adenohypophysis was larger in the Silky (14.3%) than in the RN crossbreed (8.0%) and the bantam (8.1%) cockerels (P < 0.05). From these results, it was concluded that prepubertal Silky cockerel have numerous MSH cells in the adenohypophysis suggesting a relationship to hyperpigmentation.  相似文献   

Quantities and types of ceramides and their relationships to physical properties of the horn covering the claws of clinically normal cows and cows with subclinical laminitis          下载免费PDF全文

H. Higuchi  M. Nakamura  A. Kuwano  M. Kasamatsu    H. Nagahata 《Canadian journal of veterinary research》2005,69(2):155-158

Quantities and types of ceramides and their relationships to physical properties of the horn covering the claws of clinically normal cows and cows with subclinical laminitis were investigated. Total ceramide content of the horn covering the sole and wall from cows with subclinical laminitis was 872.2 +/- 146.6 microg/g and 528.6 +/- 61.3 microg/g, respectively, and was significantly (P < 0.01, 0.05) lower than that from clinically normal cows. The mean moisture content in the claws from cows with subclinical laminitis (43.5% +/- 4.3%) was significantly (P < 0.05) higher than that in the claws from clinically normal cows. The hardness of claws from cows with subclinical laminitis (35.2 +/- 3.5) was significantly (P < 0.05) less than that of claws from clinically normal cows. Significant correlations between ceramides and moisture content (P < 0.001) and between ceramide and hardness (P < 0.001) were found in clinically normal cows and cows with subclinical laminitis. Our results indicate that decreases in ceramide contents may be related to changes in physical properties of the horn covering the claw in cows with subclinical laminitis.  相似文献   

Molecular heterogeneity in clinical isolates of Malassezia pachydermatis from dogs     

Aizawa T  Kano R  Nakamura Y  Watanabe S  Hasegawa A 《Veterinary microbiology》1999,70(1-2):67-75

Molecular investigation of 16 strains, conventionally identified to be Malassezia pachydermatis, isolated from dogs in Japan was carried out by random amplification of polymorphic DNA (RAPD) and chitin synthase 2 (CHS2) gene sequence analyses. The RAPD band patterns of 13 clinical isolates were identical to that of standard strain of M. pachydermatis (CBS-1879). The other three clinical isolates were different from the standard strain of M. pachydermatis in RAPD patterns, and two of the three isolates were identical. About 620 bp genomic DNA fragments of the CHS2 gene were amplified from the same 16 clinical isolates of M. pachydermatis by polymerase chain reaction (PCR) and sequenced. The phylogenetic analysis of the nucleotide sequences of CHS2 gene fragments of the 16 clinical isolates revealed that the 13 strains were genetically very close to the standard strain of M. pachydermatis and the other two isolates were genetically close to the standard strain of M. furfur rather than M. pachydermatis. The remaining one isolate was phylogenetically distinct from all the seven Malassezia species reported so far.  相似文献   

Cerebral high-grade astrocytoma (glioblastoma) in a cat     

Sato T  Nakamura A  Shibuya H  Shirai W  Koie H 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2003,50(5):269-271

A cerebral tumour was found in the right frontal lobe of a 7-year-old female mongrel cat. The mass showed infiltrative growth and caused deformation of the corpus callosum. Histopathologically, the tumour cells showed anaplasia, pleomorphism and mitotic figures. Necrosis and vascular proliferation were prominent. The neoplastic cells surrounded areas of necrosis, but as an indistinct pseudopalisade formation. Immunohistochemically, low numbers of tumour cells labelled positively for anti-glial fibrillary acidic protein and anti-S100 protein. Electron microscopically, the majority of tumour cells had no filaments and cytoplasmic processes, but the differentiated cells presented cytoplasmic filaments and glycogen granules. Based on these findings, the tumour was diagnosed as cerebral high-grade astrocytoma, glioblastoma.  相似文献   

Protective effects of sugar cane extracts (SCE) on Eimeria tenella infection in chickens     

El-Abasy M  Motobu M  Na KJ  Shimura K  Nakamura K  Koge K  Onodera T  Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):865-871

The effects of oral administration of sugar cane extracts (SCE) on Eimeria tenella oocysts infection in chickens were studied with 2 different experiments. In Experiment 1, 3-week-old inbred chickens (MHC; H.B15) were inoculated into the crop with SCE (500 mg/kg/day) for 1 day or 3 consecutive days, and then challenged with E. tenella sporulated oocysts (2 x 10(4) cells/chicken). In Experiment 2, 1-week-old chickens were orally administered SCE at the same dose for 3 consecutive days, and then initially infected with E. tenella sporulated oocysts (2 x 10(3) cells/chicken). At 2 and 3 weeks of age, these chickens were immunized intravenously with the mixed antigens of sheep red blood cells (SRBC) and Brucella abortus (BA). At 4 weeks of age, chickens were challenged with E. tenella sporulated oocysts (1 x 10(5)/chicken). Challenged chickens with E. tenella oocysts showed markedly decreased body weight gain/day, severe hemorrhage and great number of shedding oocysts in feces and high lesion scores. Oral administration of SCE and initial infection with oocysts (2 x 10 (3)/chicken) resulted in a remarkable improvement in body weight gain/day, hemorrhage, the number of shedding oocysts and lesion score, compare to other infected groups. In addition, SCE-inoculated chickens with the initial infection showed a significant increase in antibody responses against SRBC and BA and also improvement in decreased relative proportions of Bu-1a(+) and CD4( )cells in cecal tonsil lymphocytes of E. tenella-challenged chickens. Cecal tissues of chickens administered SCE and initially infected with E. tenella oocysts showed lower numbers of schizonts, gametocytes and oocysts than those of infected control chickens. These results suggest that SCE have immunostimulating and protective effects against E. tenella infection in chickens.  相似文献