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51.
A male Holstein-Friesian calf was born with multiple, cauliflower-like, pale pink cutaneous masses on the head and limbs. On histopathological examination, the cutaneous masses were diagnosed as congenital cutaneous fibropapillomatosis. Those lesions involved focal proliferation of sebaceous gland in the dermis. There were no histological findings to suggest bovine papillomavirus infection, such as the presence of intranuclear inclusion bodies, large keratohyalin granules, and koilocytosis. Furthermore, papillomaviral antigens and DNA were not detected by immunohistochemistry and polymerase chain reaction, respectively. These results suggested that there was no association between these cutaneous lesions and bovine papillomavirus infection, and the lesions were considered as harmartomatous changes.  相似文献   
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For the development of effective procedures to control invasive plants, it is necessary to learn about their mechanism of spread, for which an understanding of the plant's genetic variation may be important. Sicyos angulatus is a widespread and invasive weed that grows among forage crops and natural vegetation in Japan. Inter-simple sequence repeat (ISSR) genotyping was used to detect the regional patterns of genetic variation of S. angulatus in its introduced range in Japan. The goal of this research was to assess the introduction dynamics and mechanism of spread of S. angulatus in Japan. Four screened ISSR primers produced 15 reliable bands, and 12 of these were polymorphic among six areas in central and north-eastern Japan. The analysis of molecular variance ( amova ) revealed that 88.4% of genetic variation occurred within areas rather than between the two regions (1.1%), or among areas within regions (10.5%). While the total gene diversity among areas ( Ht ) was 0.1684, the coefficient of gene differentiation was low among two geographically distinct regions ( Gst = 0.053). The genetic diversity indices ( h  = 0.116; I  = 0.173) of the Fuji river area, assumed to be near the first introduction site, were not higher than other areas (total h  = 0.165; total I  = 0.263). In contrast, those of the Chikuma river and Tenryu river areas were relatively high ( h  = 0.173 and 0.187; I  = 0.276 and 0.277 respectively). The Mantel test showed no significant correlation between geographical and genetic distances. These results suggest multiple introductions from the same gene pools into both central and north-eastern regions of Japan.  相似文献   
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Polyunsaturated fatty acids (PUFAs), including arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA), are metabolized to various lipid mediators. The profile of these lipid metabolites excreted into the urine reflects inflammatory state of the body and disease conditions. In this study, we quantified 156 types of lipids in urine samples of dogs with splenic mass, using liquid chromatography-tandem mass spectrometry. We found that metabolites of prostaglandin (PG) E2, F, and D2, 8-iso-PGF, lyso-platelet activating factor, and 14,15-leukotrien C4 significantly increased in urine samples of dogs with splenic mass compared to that of healthy dogs. These observations may reflect general inflammatory responses and will help better understanding of the canine splenic mass.  相似文献   
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For semen suppliers, predicting the low fertility of service bull candidates before artificial insemination would help prevent economic loss; however, predicting bull fertility through in vitro assessment of semen is yet to be established. In the present study, we focused on the methylated CpG sites of sperm nuclear DNA and examined methylation levels to screen new biomarkers for predicting bull fertility. In frozen-thawed semen samples collected from Japanese Black bulls, for which the sire conception rate (SCR) was recorded, the methylation level of each CpG site was analyzed using human methylation microarray. According to regression analysis, 143 CpG sites related to SCR were significantly differentially methylated. Whole genome bisulfite sequence data were obtained from three semen samples and the differentially methylated regions (DMRs) that included the target CpG sites selected by human methylation microarray were confirmed. Using combined bisulfite restriction analysis, fertility-related methylation changes were detected in 10 DMRs. With the exception of one DMR, the methylation levels of these DMRs were significantly different between groups with high fertility (> 50%) and low fertility (< 40%). From multiple regression analysis of methylation levels and SCR, three DMRs were selected that could effectively predict bull fertility. We suggest that these fertility-related differences in spermatozoal methylation levels could be new epigenetic biomarkers for predicting bull fertility.  相似文献   
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The transmission risk of foot-and-mouth disease (FMD) in Japan was evaluated using a mathematical FMD transmission model. The distance-based transmission rate between farms, which was parameterized using the FMD epidemic data in 2010 in Japan, was used to calculate the local-level reproduction numbers—expected numbers of secondary infections caused by one infected farm—for all cattle and pig farms in the country, which were then visualized as a risk map. The risk map demonstrated the spatial heterogeneity of transmission risk in the country and identified risk areas with higher possibility of disease spread. This result suggests that, particularly in high-risk areas, it is important to prepare for the smooth and efficient implementation of control measures against FMD outbreaks.  相似文献   
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Leg weakness in pigs is a serious problem in the pig industry. We performed a whole genome quantitative trait locus (QTL) analysis to find QTLs affecting leg weakness traits in the Landrace population. Half-sib progeny ( n  = 522) with five sires were measured for leg weakness traits. Whole genome QTL mapping was performed using a half-sib regression-based method using 190 microsatellite markers. No experiment-wide significant QTLs affecting leg weakness traits were detected. However, at the 5% chromosome-wide level, QTLs affecting leg weakness traits were detected on chromosomes 1, 3, 10 and 11 with QTL effects ranging from 0.07 to 0.11 of the phenotypic variance. At the 1% chromosome-wide level, QTLs affecting rear feet score and total leg score were detected on chromosomes 2 and 3 with QTL effects of 0.11 and 0.13 of the phenotypic variance, respectively. On chromosome 3 and 10, some QTLs found in this study were located at nearby positions. The present study is one of the first reports of QTLs affecting fitness related traits such as leg weakness traits, that segregate within the Landrace population. The study also provides useful information for studying QTLs in purebred populations.  相似文献   
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Degeneration of the optic pathway has been reported in various animal species including cattle. We experienced a case of bilateral optic tract degeneration characterized by severe gliosis in a Japanese black cattle without any obvious visual defects. To evaluate the significance, pathological nature and pathogenesis of the lesions, we examined the optic pathway in 60 cattle (41 Japanese black, 13 Holstein and 6 crossbreed) with or without ocular abnormalities. None of these animals had optic canal stenosis. Degenerative changes with severe gliosis in the optic pathway, which includes the optic nerve, optic chiasm and optic tract, were only observed in 8 Japanese black cattle with or without ocular abnormalities. Furthermore, strong immunoreactivity of glial fibrillary acidic protein was observed in the retinal stratum opticum and ganglion cell layer in all 5 cattle in which the optic pathway lesions could be examined. As etiological research, we also examined whether the concentrations of vitamin A and vitamin B12 or bovine viral diarrhea virus (BVDV) infection was associated with optic pathway degeneration. However, our results suggested that the observed optic pathway degeneration was probably not caused by these factors. These facts indicate the presence of optic pathway degeneration characterized by severe gliosis that has never been reported in cattle without bilateral compressive lesions in the optic pathway or bilateral severe retinal atrophy.  相似文献   
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