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排序方式: 共有615条查询结果,搜索用时 15 毫秒
611.
Bilge Karatepe Mustafa Karatepe Ayşe Çakmak Zafer Karaer Gül Ergün 《Tropical animal health and production》2009,41(1):109-113
The prevalence of equine piroplasmosis caused by Theileria equi and Babesia caballi in Nigde, in central Anatolia, Turkey has remained unknown. Serum samples were obtained from a total of 125 horses and were
tested for antibodies to T. equi and B. caballi using the Indirect Fluorescence Antibody Test (IFAT). Twenty-three (18.4%) horses were seropositive for equine piroplasmosis.
Anti-T. equi was observed in 16 horses (12.8%) while anti-B. caballi was detected in 12 horses (9.6%). In addition, 5 serum samples were positive for both parasites. The prevalence rates of
antibodies to T. equi and B. caballi for female and male horses were statistically indifferent (p = 0.19 and 0.90). The difference between the seropositivity
rates to T. equi among age groups was statistically insignificant (p = 0.44) while the difference to B. caballi among age groups is statistically significant (p = 0.01). Seropositivity rates ranged from 2.9% to 25.7% for T. equi and 2.9% to 14.3% for B. caballi from the selected districts in Nigde. A statistically significant difference on seropositivity rates for the study sites
was observed for only T.equi (p = 0.03). This study indicates that T. equi is higher than B. caballi in Nigde.
This study was supported by the Scientific Research Projects Unit of Nigde University (FEB 2007/08). 相似文献
612.
Ataseven VS Dağalp SB Güzel M Başaran Z Tan MT Geraghty B 《Research in veterinary science》2009,86(2):339-344
In this report we examined the presence of specific antibodies against equine herpesvirus type 1 (EHV-1), and equine herpesvirus type 4 (EHV-4) in several equidae, including mules, donkeys, horses. The presence of EHV-1 and EHV-4 in respiratory diseases of equids, and ability of multiplex nested polymerase chain reaction (PCR) screening in simultaneous diagnosis of horses acutely infected by EHV-1 and EHV-4 were also investigated. Sera from 504 horses, mules and donkeys sampled were tested for the presence of EHV-1 and EHV-4 specific antibodies. Blood samples taken from 21 symptomatic horses and nasal swabs taken from 40 symptomatic horses were tested for the presence of EHV-1 and EHV-4 by a multiplex nested PCR. A total of 14.3% (3/21) of buffy coat samples and 32.5% (13/40) nasal swab samples were found to contain EHV-1 DNA, while 19% (4/21) buffy coat samples and 22.5% (9/40) nasal swab samples were found to be positive for EHV-4 DNA. By species, 14.5% of horses, 37.2% of mules and 24.2% of donkeys tested were EHV-1 seropositive. EHV-4 specific antibodies were detected in 237 (81.7%) of 290 horse sera tested. Results from this investigation demonstrate that EHV-1 and EHV-4 are prevalent throughout the equid population, and that donkeys and mules might also represent an important source of infection for other equids. We also showed that the multiplex nested PCR assay might be useful for diagnosis of mixed respiratory infections in horses due to EHV-1 and EHV-4. 相似文献
613.
Settlement and growth of the mussels (Mytilusgalloprovincialis,Lamarck, 1819) on different collectors suspended from an offshore submerged longline system in the Black Sea
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Meryem Yeşim Çelik Sedat Karayücel İsmihan Karayücel Bora Eyüboğlu Recep Öztürk 《Aquaculture Research》2016,47(12):3765-3776
A study of spat settlement of a submerged longline mussel culture system was carried out in Sinop area, Black Sea, between May 2008 and May 2009. The effects of six different types of collectors on spat settlement and growth were investigated. Six different types of spat settlement rope were used as polypropylene ropes with 18 mm diameter, 18 mm diameter timeworn silk rope, 22 mm diameter rope made from old hawser (OSR), 22 mm diameter ropes made from old anchovy net without pegs, 18 mm diameter old used nylon ropes and 18 mm diameter tasselled polypropylene ropes. Monthly temperature, salinity, chlorophyll‐a, total suspended matter, inorganic matter and organic matter were determined during the experimental period. The best settlement was observed on the OSR type when measured per metre (3450.00 ± 125.83 ind m?1). Consequently, the findings showed that settlement preference of spat occurred according to rope structure, and if ropes are designed to combine numerous well‐fixed tassels, spat settlement can increase. Spat growth was affected by environmental factors and rope structure. In addition, the study revealed a negative relationship between density and growth. 相似文献
614.
615.
为了解贵州湄潭茶区土壤-茶叶系统中微量元素的迁移与特征规律,采集湄潭县洗马镇、鱼泉镇等12个村镇的茶叶与土壤,利用电感耦合等离子体发射光谱仪(ICP-OES)测定茶叶、土壤中11种微量元素(Ce、Co、Fe、La、Mg、Mn、Na、Ni、Pr、Se、Zn)的含量。结果表明:上述地区土壤Ni、Zn等重金属的平均含量低于国家限定标准,所测重金属中单项污染指数(Pi)≤1,地累计指数(Igeo)≤0,表明这些地区土壤均未受到污染,且湄潭茶区达到富硒土壤要求;但Co、Pr、Ni的污染指数接近污染值界限,建议茶区减少含有Co、Pr、Ni 3种元素的有毒有害物质排放,以便解决未来元素污染的隐患,保持土壤清洁状态;对照国家标准,湄潭茶叶重金属含量未超标,且湄潭部分茶区符合富硒茶叶要求;茶叶-土壤-pH值系统中,茶叶与土壤上下层大部分元素含量有正或负相关关系,上下层土壤pH值与其部分元素含量也有正或负相关关系,茶树中Mn元素富集能力较强,Mn元素的吸收与Mg、Na、Ni、Pr、Co、Se元素的吸收具有一定拮抗作用;采用主成分分析与典则判别分析探讨湄潭茶区土壤上下层以及茶叶特征规律,发现主成分分析和典则判别分析均可将12个茶区的茶叶、土壤各自区分,其不仅实现了不同茶区土壤的区分,而且相同茶区土壤上下层也得到区分,且典则判别分析结果图中数据点的聚集性更好,以上结果证实,湄潭茶区不同地域茶叶与土壤微量元素含量特征存在差异性,特征规律明显。系统地对湄潭茶区土壤-茶叶体系中微量元素的特征规律进行探究,可为贵州省湄潭茶区土壤-茶叶体系中微量元素富集、迁移规律,以及产地溯源提供依据。 相似文献