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51.
Serological studies on Haemophilus somnus infection were carried out on 1795 cattle from 231 dairy herds in the province of Quebec. An epidemiological investigation was done in each of the dairy operations. Seroreactivity rate and mean log2 titer for all the sera were 55.4% and 4.1620 respectively. Cattle from eastern regions of Quebec demonstrated the lowest prevalence of H. somnus agglutinins. The percentage of seroreactor animals was 60.3 in herds of 100 cattle or more in comparison to 53.2 in herds of smaller size. About 75% of the animals from 16 herds in which one or more cattle showed nervous manifestations of undetermined origin over a one year period had antibodies to H. somnus. Herds in which respiratory diseases occurred had 59.6% seroreactor animals and herds in which weak calf syndrome was diagnosed over a one year period had 61.4% seroreactor animals. In 87 herds located within 20 km of feedlots, 61.8% of the sera had titers and the mean log2 titer was 4.4813. 相似文献
52.
Michael?Schloter Paolo?Nannipieri S?ren?J.?S?rensen Jan?Dirk?van?ElsasEmail author 《Biology and Fertility of Soils》2018,54(1):1-10
The living soil is instrumental to key life support functions (LSF) that safeguard life on Earth. The soil microbiome has a main role as a driver of these LSF. Current global developments, like anthropogenic threats to soil (e.g., via intensive agriculture) and climate change, pose a burden on soil functioning. Therefore, it is important to dispose of robust indicators that report on the nature of deleterious changes and thus soil quality. There has been a long debate on the best selection of biological indicators (bioindicators) that report on soil quality. Such indicators should ideally describe organisms with key functions in the system, or with key regulatory/connecting roles (so-called keystone species). However, in the light of the huge functional redundancy in most soil microbiomes, finding specific keystone markers is not a trivial task. The current rapid development of molecular (DNA-based) methods that facilitate deciphering microbiomes with respect to key functions will enable the development of improved criteria by which molecular information can be tuned to yield molecular markers of soil LSF. This review critically examines the current state-of-the-art in molecular marker development and recommends avenues to come to improved future marker systems. 相似文献
53.
Twenty-nine new records are reported from Turkey. The fungi species, including their macro-and microscopic features and distributions,
are described.
http://www.phytoparasitica.org posting July 14, 2004. 相似文献
54.
本试验旨在研究玉米青贮与花生秧配比对奶牛瘤胃中花生秧降解特性的影响。选择4头体重、生理状态、生产性能相近,装有永久瘤胃瘘管的中国荷斯坦奶牛,分别饲喂含有玉米青贮与花生秧不同配比的全混合日粮(TMR),3种TMR中玉米青贮与花生秧的干物质(DM)配比分别为3.9∶1.0(A组)、1.2∶1.0(B组)、0.4∶1.0(C组)。试验分3期进行,依次进行A、B、C组试验。每期预试15 d,采样期4 d;共57 d。采用尼龙袋瘤胃降解技术测定花生秧在奶牛瘤胃中DM、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的72 h瘤胃降解率,并求得目标养分的动态降解参数及有效降解率。结果表明:1)花生秧的DM在瘤胃中有效降解率为56.49%~59.62%,CP为40.45%~47.36%,NDF为33.26%~35.20%,ADF为36.31%~37.45%。2)B组DM的有效降解率显著高于C组(P0.05),极显著高于A组(P0.01);B、C组的CP有效降解率显著高于A组(P0.05)。3)B、C组的NDF快速降解部分含量显著高于A组(P0.05);3种TMR对花生秧粗NDF和ADF有效降解率无显著影响(P0.05)。由此可见,花生秧具有较高的饲用价值。本试验条件下,玉米青贮与花生秧DM配比为1.2∶1.0时,可有效提高花生秧DM和CP的瘤胃降解率。 相似文献
55.
Mogens T Christophersen Nana Dupont Kristina S Berg-S?rensen Christel Konnerup Tina H Pihl Pia H Andersen 《Acta veterinaria Scandinavica》2014,56(1):20
Background
Outcomes of colic treatment are of great interest to clinicians, horse owners and insurers. One commonly used criterion of success is the overall short-term survival rate. This is used as to compare treatments and to measure quality of veterinary care, but may be biased by demographic or social factors such as attitudes towards animal suffering and euthanasia. The aims of this study were to 1) describe and analyse characteristics in horses with signs of colic referred to the University Hospital for Large Animals (UHLA), University of Copenhagen, Denmark over a 10-year period and 2) to compare these rates with those published in other comparable studies.Results
The overall survival rate for colic horses over the 10-year study period was 68% (confidence intervals (CI): 66–71%; 1087/1588). In the medical group, 1093 horses, short-term survival was 87% (CI: 85–89%). Thirty one % of referred horses were given diagnoses requiring surgical intervention (CI: 29–33%). In this group 32% of the horses were euthanized before surgery (CI: 28–36%; 159/495). Of the surgical cases 27% (CI: 23-31%) were euthanized or died during surgery. Of the horses that recovered from surgery 25% died or were euthanized (CI: 19–32%; 48/189), while 75% survived to discharge (CI: 68–81%).Conclusions
The short term survival rates of Danish horses with colic were similar or lower to those reported from other countries. Apart from variability of veterinary care, attitudes towards euthanasia vary among the countries, which may bias the outcomes. This study indicates that qualitative interview studies on owners’ attitudes towards animal suffering and euthanasia need to be conducted. Our opinion is that survival rates are not valid as sole indicators of quality of care in colic treatment due to selection bias. If the survival rates are to be compared between hospitals, techniques or surgeons, prospective studies including mutually agreed-on disease severity scores and a predefined set of reasons for euthanasia are needed. 相似文献56.
57.
Tomoya?Okunishi Norikazu?Sakakibara Shiro?Suzuki Toshiaki?UmezawaEmail author Mikio?Shimada 《Journal of Wood Science》2004,50(1):77-81
Secoisolariciresinol dehydrogenase activity was detected for the first time from Daphne odora and Daphne genkwa (Thymelaeaceae), which are known to produce optically pure (+)-matairesinol. In sharp contrast, (–)-matairesinol was formed selectively over the (+)-antipode by the secoisolariciresinol dehydrogenase preparation from both D. odora callus and D. genkwa shoots. 相似文献
58.
Annual net production of the five Sargassaceae species in Yoro,western Wakasa Bay,Sea of Japan 总被引:1,自引:0,他引:1
Kousuke?YatsuyaEmail author Tomokazu?Nishigaki Akio?Douke Yozo?Wada 《Fisheries Science》2005,71(5):1098-1106
ABSTRACT: Annual net production of the five Sargassaceae species was investigated in Yoro, western Wakasa Bay, Sea of Japan. The Sargassaceae species were collected at a depth of 2.0–2.5 m and subjected to stratified clipping for 13 months. Annual net production was estimated at 2407 g dry wt/m2 for Sargassum patens , 2132 g dry wt/m2 for Sargassum macrocarpum , 1458 g dry wt/m2 for Sargassum siliquastrum , 1197 g dry wt/m2 for Myagropsis myagroides , and 1471 g dry wt/m2 for Sargassum piluliferum . The ratio of annual net production to maximum biomass (P/Bmax ) for these species ranged between 1.3 and 1.7, being higher than in previous studies which used the same method. Winter storms with strong wave exposure and relatively calm condition in Yoro were considered to augment P/Bmax . The total losses estimated from the different units of stratified clipping were compared. If larger and less segregated units were applied, the total loss would decrease. It was suggested that a 50 cm stratum would be applicable to the larger species (3 m or longer) and a stratum of 20 cm or less would be applicable to mid-sized or smaller species (less than 3 m). 相似文献
59.
K J S?rensen 《Nordisk veterinaermedicin》1975,27(4):208-212
In 1956 a disease of nursing pigs previously unreported in Denmark, was observed in several swine herds. The disease syndrome appeared identical with that later described by Roe and Alexander in 1958 and by S. F. Cartwright and M. Lucas in 1968. Since 1956 there have been no reports of such outbreaks in Danish herds. To investigate whether the virus is still present, a survey was carried out to detect neutralizing antibodies in sera from a number of boars using a micro technique. In 144 sera from Jutland 12% had titers ranging from 10 to 32 ND-50, 22% from 32 to 90, 37% from 90 to 256, 14% from 256 to 724 and 3% above 724 ND-50 with a total of 86% positive. Of 174 sera from the rest of the country 16% had titers ranging from 10 to 32 ND-50, 18% from 32 to 90, 28% from 90 to 256, 13% from 256 to 724 and 3% exceeding 724 ND-50 with a total of 79% positive. 相似文献
60.
采用平板计数法和聚合酶链式反应( PCR)-变性梯度凝胶电泳( DGGE)技术分析免疫增强剂党参对仿刺参( Apostichopus japonicas)肠道菌群结构的影响。将初始体重为(18.00±2.00) g的仿刺参随机分为2组(对照组、试验组),每组6个重复,每个重复12只。对照组投喂海泥、鼠尾藻粉按照1∶1的质量比配制的饵料,试验组饵料中以鼠尾藻粉质量的2%添加党参,连续投喂28 d。结果表明:应用免疫增强剂党参不仅能够显著提高仿刺参的特定生长率( P<0.05),降低其饵料系数(P<0.05),而且能够显著增加仿刺参肠道内容物中异养菌的数量(P<0.05);序列统计分析显示投喂党参后仿刺参肠道细菌优质序列比例显著增加( P<0.05),试验组达97.57%,对照组仅为80.22%;Beta多样性分析反映投喂党参后仿刺参肠道微生态环境发生了变化,其多样性系数范围在14.91%~15.47%、15.47%~16.21%、14.91%~16.21%;丰度分析显示投喂党参后仿刺参肠道内容物中变形菌门( Proteobacteria)和拟杆菌门( Bacteroidetes)丰度提高,疣微菌门( Verrucomicrobia)、放线菌门( Actinobacteria)和厚壁菌门( Firmiaites)丰度降低;聚类分析显示试验组与对照组肠道菌群结构相似性系数为0.97。由此可见,免疫增强剂党参可提高仿刺参的特定生长率,降低饵料系数,增加肠道异养菌数量和优势菌群丰度,优化肠道微生态环境。 相似文献