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321.
Nasal papules and oral ulcers were observed in calves that were group-housed at a dairy farm. The calves were diagnosed with bovine papular stomatitis (BPS) due to parapoxvirus (PPV) infection based on virologic examinations using polymerase chain reaction to detect PPV. To prevent the spread of BPS, we isolated the affected calves, made procedural changes so that the affected herd was managed after the healthy herd, disinfected the bedding with slaked lime, disinfected the stalls and fences with invert soap, and changed the animals’ feed to soft grass which does not damage the oral cavity. As a result, we succeeded in control the infection quickly.  相似文献   
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Seventeen isolates of infectious bronchitis virus (IBV) were obtained from various prefectures of Japan during 2008–2019 and genetically analyzed. The IBV isolates were classified into six genetic groups, based on phylogenetic analysis of the S1 gene. The S1 genotypes were distinguishable by a newly developed restriction fragment length polymorphism (RFLP) method using three endonucleases, Hae II, Hpa I, and Fok I. Moreover, the isolates were classified into four genetic groups, based on phylogenetic analysis of the S2 gene. However, novel genetic groups based on a combination of S1 and S2 genotypes, which were undetected previously, were confirmed in this study, indicating that various recombinant IBV strains were prevalent in poultry in Japan.  相似文献   
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ABSTRACT:   The oxidative stability of lipids from salmon roe and herring roe was compared with those of commercial fish oils originated from sardine and tuna. Both fish roe lipids contained high amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Total EPA and DHA was more than 35% of total fatty acids in both roe lipids. On the basis of oxygen consumption, fish roe lipids showed the higher oxidative stability than both fish oils. This tendency in oxidative stabilities was also confirmed by the determination of propanal formation during oxidation. Analyses of lipid compositions suggested that the higher oxidative stabilities of fish roe lipids would be mainly due to the presence of phospholipids in them. Dietary effects of salmon and herring roe lipids were also determined. Little increase in total cholesterol level was observed in plasma lipids in rats fed salmon and herring roe lipids, although cholesterol content in fish roe lipids were 6.3% and 9.7% of total lipids for salmon roe and herring roe.  相似文献   
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Changes in serum thyroxine (T4), estradiol-17β (E2) and testosterone (T) levels during the parr-smolt transformation (smoltification) were investigated in the masu salmon (Oncorhynchus masou) in 1985 and 1987. T4 showed a peak in levels at the early stage of smoltification and E2 and T levels peaked almost at the same time. There were no significant differences between the concentrations of serum hormones in female and males. During smoltification, germ cells in the peri-nucleolus and spermatogonia stage were present in the ovary and testis, respectively. These results suggest that E2 and T may be involved in smoltification in the masu salmon.  相似文献   
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To gain better understanding of rates of decay of wooden check dams with different structures under different climate conditions, several dams of this type were examined under different environmental conditions over a 3 to 5-year period post-construction. Because a linear relationship was found between the mean (μ) and standard deviation (σ) of pilodyn penetration depth, mean penetration depth was taken as the indicator of deterioration, and relationships with check dam structural features and climate data recorded by AMEDAS were investigated. Multiple linear regression analysis revealed that temperature, climate index (CI) computed from rain days, warmth index computed from daily and annual mean air temperature, and altitude were the climate variables with the most effect on the rate of decay. With regard to dam structural features, factors such as specific discharge rate, water through width, dam length, and dam height had the most effect. Accordingly, in an effort to summarize the effects of climatic conditions and structural features, CI, altitude, and dam height were extracted as the most significant explanatory variables, and a formula for prediction of μ was obtained for each factor for up to 5 years post construction. The results showed that by taking into consideration regional conditions and calculating CI values from AMEDAS data, it is possible to predict the extent of decay of wooden check dams.  相似文献   
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