新城疫病毒融合蛋白裂解位点基因的分离克隆及在原核细胞中的表达

用ＳＰＦ鸡胚繁殖新城疫病毒（ＮＤＶ）Ｆ４６Ｅ９株（强毒）、ＬａＳｏｔａＥ４株（弱毒），对病毒进行纯化，抽提ＲＮＡ。用１对均为２７个碱基的引物进行ＲＴ－ＰＣＲ，扩增出了２个毒株的融合蛋白裂解位点（Ｆｃ）基因。将Ｆｃ基因定向克隆入ｐＵＣ１８的ＥｃｏＲＩ和ＳａｌⅠ位点之间，获得２个毒株Ｆｃ基因克隆ｐＵＣＦ４６Ｆｃ和ｐＵＣＬａＦｃ，用ＥｃｏＲＩ／ＳａｌⅠ双酶切法、ＰｓｔⅠ单酶切法、ＰＣＲ法和核酸探针法对其进行了鉴定。将鉴定好的ＬａＳｏｔａＥ４Ｆｃ基因定向导入表达载体质粒ｐＢＶ２２１，获得重组子ｐＢＶＬａＦｃ。ＰＣＲ和内切酶酶切法鉴定表明，Ｆｃ插入的位置和方向都正确无误。用Ｅ．ｃｏｌｉＤＨ５α通过热诱导法进行了表达。用ＳＤＳ－ＰＡＧＥ和Ｗｅｓｔｅｒｎ－ｂｌｏｔ法检测了表达产物。结果表明，有１条能够与ＮＤＶ多抗反应的特异条带，分子量约１５７００，与预期大小一致，说明是Ｆｃ基因的表达产物     

新城疫活疫苗对控制鸡大肠杆菌病的效果观察

为了研究鸡新城疫活疫苗紧急免疫控制鸡大肠杆菌病的效果,通过大肠杆菌人工感染30日龄蛋鸡,待出现病症后,紧急免疫新城疫La-sota弱毒苗(Ⅳ系)4羽份.免疫后5～17 d,通过血凝抑制试验测定血清新城疫抗体水平,试验组新城疫抗体水平逐步提高,对照组抗体略有下降,免疫后17 d两组抗体水平差异显著(P＜0.05);对照组...     

鸡传染性法氏囊病超强毒LX株的分离鉴定

从一免疫失败鸡场中分离到１株鸡传染性法氏囊病野毒株,命名为ＬＸ株。经血清学、鸡胚接种、病毒形态、外源病毒（ＣＡＡ、ＮＤＶ和ＩＢＶ）排除试验等证实该分离物为纯净的ＩＢＤＶ。人工感染试验表明,该ＬＸ株接种８龄ＳＰＦ鸡后第２天鸡只精神 沉郁,拉白色或绿色粪便,发病率为１００％,第３￣４天出现死亡高峰,而后很少引起死亡,死亡率达９２．３％,剖检可见全身性出血素质,法氏囊呈“紫葡萄样”外观,脾脏肿大,胸腺萎     

口蹄疫病毒非结构蛋白2C基因在昆虫细胞中的表达及应用

研究口蹄疫病毒(FMDV)非结构蛋白(NSP) 2C在区分灭活疫苗免疫动物与自然感染动物方面的意义.本研究将FMDV NSP 2C基因,克隆到穿梭载体pFast-bac- HT-B,将其转入含骨架载体Bacmid的DH10Bac,经蓝白斑筛选得到重组骨架质粒Bacmid-2C.将Bacmid-2C转染昆虫细胞Sf9,鉴定正确后,经3次增殖获得高滴度的P-3代病毒后,在High Five细胞中进行目的蛋白的表达.SDS-PAGE结果显示在High Five细胞中得到了相对分子质量约为38.93 ku的目的蛋白2C,Western blotting及Dot-ELISA结果显示,该表达产物对FMDV感染动物阳性血清有良好的反应性.以电泳纯化的2C蛋白为抗原建立间接ELISA,检测健康非免疫动物、免疫动物及FM-DV试验感染动物血清,结果表明2C-ELISA不但能区分免疫动物和感染动物的血清,而且还能检测FMDV感染早期动物血清中的2C抗体.说明昆虫细胞表达的2C蛋白可作为FMDV疫苗免疫动物与自然感染动物鉴别诊断的良好抗原.2C基因在Bac-to-Bac系统中的成功表达为建立通过检测几种NSP抗体,筛查感染及隐性带毒动物,净化畜群的方法奠定了基础.     

高寒退化草地恢复中种子包衣对出苗的影响

采用植物性吸水材料对垂穗披碱草(Elymus nutant)和山野豌豆(Vicia amoena)种子进行包衣处理,在模拟高寒草地条件下观察包衣种子的出苗,同时测定包衣混合物的持水力.结果表明,最适条件下两种牧草种子的出苗率分别为86%和88%;在模拟条件下,种子的出苗率分别为38%和24%.经过包衣处理后,种子的出苗...     

复方恩诺沙星粉临床试验

复方恩诺沙星250mg/L试验剂量对家蚕黑胸败血病的治疗保护率达95.24%,对灵菌败血病的治疗保护率在91.44%,是保护率大于90%的最低配比。     

A multicentric retrospective study of serum/plasma urea and creatinine concentrations in dogs using univariate and multivariate decision rules to evaluate diagnostic efficiency

BACKGROUND: Urea and creatinine are the most frequently used indirect markers in plasma and serum of glomerular filtration rate in dogs. Both have been shown to lack sensitivity but their diagnostic efficiency for the diagnosis of kidney disease has been minimally investigated. OBJECTIVE: The purpose of this retrospective study was to investigate the influence of possible factors of variation on both analytes and to determine whether specific decision rules should be drawn up for subpopulations of dogs. METHODS: The results of urea and creatinine measurements, breed, sex, age, and health status (healthy, renal disease, or nonrenal disease) of 3822 dogs were collected from the archives of 5 veterinary clinics. Data were analyzed with univariate and multivariate decision rules with and without adjustment. RESULTS: There were significant effects and interactions of almost all of the sources of variation. Slight improvements in diagnostic efficiency were obtained by adjusting the decision rules to these sources of variations. Univariate decision rules gave approximately the same diagnostic efficiency for urea and creatinine concentrations, with sensitivity and specificity in the range of 70% and 90%, respectively, using the upper limit of the reference interval as the threshold value. Multivariate decision rules provided only minor improvements in diagnostic efficiency. CONCLUSION: Simultaneous measurement of both urea and creatinine is of limited diagnostic value over the analysis of a single variable. Creatinine is the preferred analyte as it is affected by fewer extrarenal factors of variation.     

奶牛蹄病的治疗

将患有蹄病的牛按病情严重程度分三级,在每级中各选出12头,并将36头随机分成4组,每组共9头。第1组为对照组,第2组每头牛日粮中加35%石粉18g,第3组每头牛日粮中加硫酸锌1.2g,第4组每头牛日粮中同时加35%石粉18g和硫酸锌1.2g。同样护理,每星期对试验牛群进行修蹄及常规治疗。经过1个月的治疗第1组治愈1头,有效3头,无效5头;第2组治愈2头,有效6头,无效1头;第3组治愈3头,有效4头,无效2头;第4组治愈7头,有效2头,无效0头。卡方检测除第2、3两组差异不显著外,其他各组之间差异显著。说明在日粮中适量提高钙和锌对奶牛蹄病有良好的预防和治疗作用。     

Mycoplasma pneumonia of swine (MPS) resistance and immune characteristics of pig lines generated by crossing an MPS pulmonary lesion selected Landrace line and a highly immune capacity selected Large White line

To understand the influence of crossbreeding on Mycoplasma pneumonia of swine (MPS) resistance and immune characteristics, two crossbred lines were characterized. One crossbred line, LaWa, was generated by crossing the MPS pulmonary lesion selected Landrace line (La) and the highly immune‐selected Large White line (Wa). The second crossbred line, LaWb, was generated by crossing the La line and the nonselected Large White line (Wb). The crossbred LbWb line (nonselected Landrace line × nonselected Large White line) and the La line were used as controls. The LaWa and LaWb lines had an intermediate level of MPS lung lesions between La and LbWb lines, although the difference was not statistically significant. After stimulation with sheep red blood cells (SRBCs), the LaWb and LaWa lines showed immune characteristics similar to that of the La line; the number of monocytes in peripheral blood increased, while B cells, T cells, secretion of SRBC‐specific immunoglobulin G, and interleukin (IL)‐13 decreased. Additionally, the number of natural killer (NK) cells and the expression of IL‐4 and IL‐17 were significantly higher in the LaWb and LaWa lines, respectively. These data suggested that crossbreeding of La and Wa lines resulted in the inheritance of some of the selected immune responses.     

Identification of Neofabraea species causing bull's eye rot of apple in Poland and their direct detection in apple fruit using multiplex PCR

Based on partial sequence analysis of the β‐tubulin gene, 19 isolates of fungi causing bull's eye rot on apple in Poland were classified into species: Neofabraea alba, N. perennans and N. kienholzii. To the authors’ knowledge, the detection of N. kienholzii is the second in Europe and the first in Poland. Species affiliation of these fungi was confirmed by a new species‐specific multiplex PCR assay developed on the basis of previously published methods. The new protocol allowed for the specific identification of bull's eye rot‐causing species, both from pure cultures and directly from the skin of diseased or apparently healthy apples. In 550 samples of diseased fruits collected from nine cold storage rooms located in three regions of Poland, in 2011 and 2012, N. alba was detected as the predominant species causing bull's eye rot, occurring on average in 94% of the tested samples. Neofabraea perennans was found in a minority of apple samples, N. kienholzii was found only in two apple samples, while N. malicorticis was not detected in any sample tested. In tests on 120 apparently healthy fruits, only N. perennans was detected in a single sample. The results of genetic diversity analyses of bull's eye rot‐causing fungi based on the β‐tubulin gene sequence and an ISSR (inter‐simple sequence repeat) PCR assay with two primers were consistent, showing the expected segregation of tested isolates with respect to their species boundaries. However, the genetic distance between N. perennans and N. malicorticis was very low, as reported previously.