Protection of chicken against very virulent IBDV provided by in ovo priming with DNA vaccine and boosting with killed vaccine and the adjuvant effects of plasmid-encoded chicken interleukin-2 and interferon-��

The aim of this study was to examine the efficacy of in ovo prime-boost vaccination against infectious bursal disease virus (IBDV) using a DNA vaccine to prime in ovo followed by a killed-vaccine boost post hatching. In addition, the adjuvant effects of plasmid-encoded chicken interleukin-2 and chicken interferon-γ were tested in conjunction with the vaccine. A plasmid DNA vaccine (pcDNA-VP243) encoding the VP2, VP4, and VP3 proteins of the very virulent IBDV (vvIBDV) SH/92 strain was injected into the amniotic sac alone or in combination with a plasmid encoding chicken IL-2 (ChIL-2) or chicken IFN-γ (ChIFN-γ) at embryonation day 18, followed by an intramuscular injection of a commercial killed IBD vaccine at 1 week of age. The chickens were orally challenged with the vvIBDV SH/92 strain at 3 weeks of age and observed for 10 days. In ovo DNA immunization followed by a killed-vaccine boost provided significantly better immunity than the other options. No mortality was observed in this group after a challenge with the vvIBDV. The prime-boost strategy was moderately effective against bursal damage, which was measured by the bursa weight/body weight ratio, the presence of IBDV RNA, and the bursal lesion score. In ovo DNA vaccination with no boost did not provide sufficient immunity, and the addition of ChIL-2 or ChIFN-γ did not enhance protective immunity. In the ConA-induced lymphocyte proliferation assay of peripheral blood lymphocyte collected 10 days post-challenge, there was greater proliferation responses in the DNA vaccine plus boost and DNA vaccine with ChIL-2 plus boost groups compared to the other groups. These findings suggest that priming with DNA vaccine and boosting with killed vaccine is an effective strategy for protecting chickens against vvIBDV.     

Imaging evaluation of the liver using multi-detector row computed tomography in micropigs as potential living liver donors

The shortage of organ donors has stimulated interest in the possibility of using animal organs for transplantation into humans. In addition, pigs are now considered to be the most likely source animals for human xenotransplantation because of their advantages over non-human primates. However, the appropriate standard values for estimations of the liver of micropigs have not been established. The determination of standard values for the micropig liver using multi-detector row computed tomography (MDCT) would help to select a suitable donor for an individual patient, determine the condition of the liver of the micropigs and help predict patient prognosis. Therefore, we determined the standard values for the livers of micropigs using MDCT. The liver parenchyma showed homogenous enhancement and had no space-occupying lesions. The total and right lobe volumes of the liver were 698.57 ± 47.81 ml and 420.14 ± 26.70 ml, which are 51.74% and 49.35% of the human liver volume, respectively. In micropigs, the percentage of liver volume to body weight was approximately 2.05%. The diameters of the common hepatic artery and proper hepatic artery were 6.24 ± 0.20 mm and 4.68 ± 0.13 mm, respectively. The hepatic vascular system of the micropigs was similar to that of humans, except for the variation in the length of the proper hepatic artery. In addition, the diameter of the portal vein was 11.27 ± 0.38 mm. In conclusion, imaging evaluation using the MDCT was a reliable method for liver evaluation and its vascular anatomy for xenotransplantation using micropigs.     

新疆双峰驼的品种特征及饲养管理要点

新疆双峰驼产于新疆准噶尔盆地和塔里木盆地边缘及天山南北坡的荒漠草场、荒漠草原草场地带。新疆双峰驼在长期的进化过程中,形成了适应独特的荒漠化生态条件的器官和生活习性,具有耐粗饲、耐渴、耐饥饿、耐热、耐寒、抗风沙及善长途奔走等诸多特性。作者介绍了新疆双峰驼的品种特征、生产性能及饲养管理的特点,并对新疆双峰驼的饲养前景作了展望。     

牛心朴子生物碱的GC-MS分析

采用GC－MS联用技术从牛心朴子的全草中分离鉴定出12种生物碱，分别为2，4，6－三甲基吡啶；2，6－二乙基吡啶；4－（1－哌啶）－2－丁酮；苯并噻唑；3－正丙基－2，6－二苯基吡啶；娃儿藤定碱；2，2，6，6－四甲基－4－哌啶酮；Diazen,butyl[1-(2,2-dimethylhydr)];5,10-Diethoxy-2,3,7,8-tetrahydro-1H,6H-dipyrrolo[1,2-a;1^1，2^1-d]pyrazine;9-Azabicyclo[3,3,1]nonane,9-methyl-;Piperidino[2,3-b]2,3-dihtdroindene,1-methyl-4,4a-diethyl-6-methyl-;7,14-Methano-4H,6H-dipyrido[1,2-a:1^1,2^1-E][1,5]diazocin-4-one,7,7a,8,9,10,11,13,14-oc-tahydro-,[7R-(7,alpha,7a,alpha,14,alpha)]。其中后6种为首次从该植物中分得。     

CecA-Mag及其突变体在Pichia pastoris中的表达及抗菌活性试验

参考相关天蚕素类抗菌肽的作用机制及抗菌肽结构与功能关系的假说,设计了杂合肽CecA-mag的3个突变体并利用重组聚合酶链式反应定点诱变技术,使突变体得以合成,利用琼脂孔扩散法检测CecA-mag和其突变体对金黄色葡萄球菌、大肠埃希菌等临床分离菌株的抑菌效价.结果显示,3个突变体的抑菌活性比CecA-mag分别提高了1....     

猪细小病毒7型SYBR Green Ⅰ荧光定量PCR检测方法的建立及临床样品的检测

采用PCR方法扩增猪细小病毒7型(PPV7)衣壳蛋白基因保守区域493 bp,将其克隆到pMD18-T载体,构建重组质粒作为标准阳性质粒,以其为模板建立用于检测PPV7的SYBR GreenⅠ实时PCR检测方法,并验证其灵敏性、特异性和重复性。结果表明,本试验建立的SYBR GreenⅠ荧光定量PCR检测方法在2.85×10^1~2.85×10^8拷贝/μL呈良好的线性关系,相关系数为0.995,斜率为4.158,灵敏度可达到2.85×10^1拷贝/μL。该方法对于猪繁殖障碍性传染病常见病原如PRRSV、PCV2和PRV未出现特异性扩增,表明特异性好。所有标准曲线在溶解温度为83.103℃时出现单一的特异峰。使用本方法检测了2017年山东地区7家养猪场216份临床样品,总阳性率为12.5%。     

新疆南疆籽棉超高产机理研究

为探寻新疆南疆地区籽棉9000 kg·hm-2超高产机理以及相关的指标,对南疆地区生态条件下超高产田、高产田、中高产田进行了调查研究与数据采集。研究发现:要获得超高产,首先要有良好的基础地力,有机质含量超10 g·kg-1,种植密度18×104~21×104株·hm-2为宜;其次,塑造良好株型,株高65~75 cm,茎粗接近10 mm,果枝9~10台,棉铃空间分布均匀,纵向上、中、下果枝棉铃比例3.2∶4.7∶2.1,横向第一、二果节比例7∶3,初花至盛铃LAI、SPAD、Pn一直维持较高水平,盛铃前后达到最大,后期下降缓慢;最后,氮磷钾分配上,前期差异不大,进入花铃期生殖生长明显增强,蕾花铃氮磷钾比例明显增大,一直维持到见絮,超高产处理的蕾花铃干物质量比例明显高于其它处理8%以上,见絮时蕾花铃干物质量达到了6 402 kg·hm-2。以指标数据作参考,塑造良好株型,协调棉铃空间分布,维持较高较长的光合速率,减缓LAI、SPAD下降速度,促进生殖生长,合理养分分配,便能实现产量目标。     

不同抗氧化剂对辐照熟五花肉脂肪氧化的影响

本文研究了几种抗氧化剂对真空包装辐照熟五花肉中脂肪氧化的影响。在熟五花肉中分别添加0.02%的茶多酚(TP)、迷迭香(Rosemary)、特丁基对苯二酚(TBHQ)、二丁基羟基甲苯(BHT)、维生素E(VE)5种抗氧化剂后,经6kGy辐照,4℃贮藏,试验结果表明抗氧化剂可以降低辐照熟五花肉的TBA值、POV值,其中以TBHQ与TP效果最好,其他依次为Rosemary、BHT和VE。     

Analysis of food preference and competition based on stomach contents of fish species inhabiting fresh and brackish waters in South Korea

We analysed the stomach contents of fish species inhabiting fresh and brackish waters of South Korea to improve our understanding of feeding preferences and competition among them. The stomach contents of 54 fish species contained 237 genera, 187 families, 84 orders, 37 classes and 25 phyla. Faunal food items included 164 genera, 129 families, 47 orders, 23 classes and 16 phyla. Floral food items were relatively limited, comprising 73 genera, 58 families, 37 orders, 14 classes and nine phyla. The most consumed faunal food item was Chironomidae (Diptera), whereas the most consumed floral food item was Fragilariaceae (Fragilariales). The 54 fish species were classified into six groups using hierarchical and nonmetric multidimensional analysis based on their food preferences: Group 1 (G1) fishes were zooplanktivores; group 2 (G2) fishes mainly consumed Malacostraca, Maxillopoda and other fishes (e.g. Osmeriformes); groups 3 (G3) and 4 (G4) consumed Chlorophyta, Cyanobacteria and Bacillariophyta; and groups 5 (G5) and 6 (G6) consumed macroinvertebrates. Network analysis was used to link fishes with their food items. The highest hub score for food items was for macroinvertebrates, including Diptera (13.9), Ephemeroptera (11.1) and Trichoptera (8.2). Niche breadth analysis represented the diversity of food items among the feeding groups (G1–G6). Food item diversity was high for planktivores (G1 and G3) and omnivores (G4). Conversely, the dietary diversity of carnivores (G2) and insectivores (G5) was limited. Competitive relationships between fishes, as represented by the niche overlap in G5 (insectivores), were higher than those between other groups.     

西气东输管道工程宁夏段水土保持生物植被恢复措施研究

西气东输管道工程东西向横贯我国中部,沿线地貌复杂多变,工程建设易造成植被破坏,水土流失,沙漠化加剧,因此采取相关的生物植被恢复措施防治水土流失和环境恶化十分必要。就西气东输工程宁夏段的建设引发的水土流失及环境问题,在对项目区气候、地形、土壤条件等因素的综合考察分析的基础上,分2大地类,6个立地类型,提出了相应的水土保持生物植被恢复措施,进行生态恢复与重建。该项研究对于创建西气东输绿色管道、生态长廊,保证管道安全和区域生态环境安全有着重要意义。