应用异烟肼复合剂治疗奶牛结核病的试验研究

对一群经两次检疫均为结核菌素阳性并经临床学、病理解剖学和细菌学证实为结核杆菌感染奶牛，随机选择２０头奶，每日按２５ｍｇ／ｋｇ体重投与异烟肼复合剂，连服６０日，接着再按上述剂量每隔一天给药一次连服６０次。结果感染牛在治疗后的７０天转阴率为５０％；治疗后１６５天转阴率为８０．１％；未经治疗的７头对照牛仍呈阳性。     

牛结核γ-干扰素ELISA检测方法在检疫工作中的应用

为评价牛γ-干扰素ELISA检测方法检测牛结核的效果及国产试剂盒的检测效果,本试验首先将国产试剂盒与Prionics试剂盒对42份相对阳性的样品和105份相对阴性的样品进行对比研究。然后对5个规模化牛场的3000头奶牛首先进行国产单纯结核菌素颈部皮内变态反应试验,3天后选取皮内变态反应阳性和可疑及部分阴性牛共418头,进行牛γ-干扰素试验。结果国产试剂盒对阳性和阴性样品的检测敏感性和特异性分别为95.2%和100%,与Priobics试剂盒的符合率为99.3%。表明国产试剂盒与进口试剂盒的检测能力一致,牛γ-干扰素检测方法准确可靠。5个牛场的3000头奶牛单纯结核菌素颈部皮内变态反应试验阳性为138头,可疑105头。γ-干扰素试验对418头奶牛的检测,其中阳性74头,与颈部皮内变态反应（可疑牛暂时视为阴性）的符合率为60.5%。     

鹿结核病流行株与卡介苗差异基因原核表达质粒的构建及表达

以吉林农业大学经济动物疾病实验室保存的鹿体内分离并鉴定的结核病流行株的基因组为模板,应用PCR方法从已构建的鹿结核病野毒株与卡介苗差异基因文库中扩增RD1区的Rv3872、Rv3873、Rv3874、Rv3875和Rv3878 5段目的基因,分别与p MD18-T Simple Vector连接,经PCR、酶切鉴定后的阳性重组克隆质粒与原核表达载体p GEX-4T-1连接并进行原核表达,采用谷胱甘肽琼脂糖亲和层析方法对目的蛋白进行纯化,通过SDS-PAGE和Western blot对表达产物的反应原性进行初步研究。基因测序结果显示差异基因与期望的序列一致,并在大肠杆菌中成功诱导表达,获得以可溶形式表达的目的蛋白,经SDS-PAGE分析目的蛋白的相对分子量与理论值相符,经Western blot鉴定纯化好的目的蛋白能与鹿结核病的阳性血清发生反应,具有良好的反应原性,为其在鹿结核病血清诊断学中的应用奠定了试验基础。     

应用变态反应方法诊断鹿结核病的研究

利用牛型新，旧结核菌素（ＰＰＤ，ＯＴ），禽型旧结核菌素（ＯＴ）为变应原，采用变态反应点眼法进行了鹿结核病的诊断研究。结果表明：变应原以牛型ＯＴ为最好，其敏感性高于禽型ＯＴ，检出率高于牛型ＰＤＤ；一次二回点眼的阳性率可达９２．３３％，且较一次一回的检出率高４４．６％；判定最佳时间为３，６，９ｈ。用牛型ＯＴ一次二回点眼法抽检了１１个鹿场２４５０余头成年鹿，其阳性率最高者为９９．８％，最低者为１．１％，     

牛源分枝杆菌变应原对免疫豚鼠变态反应试验

本文采用牛结核PPD检出阳性牛分离的分枝杆菌(包括有牛分枝杆菌、瘰疬分枝杆菌、乌胞内分枝杆菌2型及9型、副结核分枝杆菌、偶发分枝杆菌以及草分枝杆菌等),制成灭活免疫原进行豚鼠接种,并以各种分枝杆菌PPD进行变态反应检查,以观察其发生交叉反应的情况。试验结果表明:各种分枝杆菌除发生主反应外,均表现出明显的相互交叉的变态反应,尤以瘰疬分枝杆菌、乌胞内分杆菌2型及9型、副结核分枝杆菌以及牛分枝杆菌等交叉严重。提示:在牛结核及副结核的检疫中出现其它分枝杆菌干扰的假阳性反应。     

黄葵素对结核分枝杆菌的抑杀作用研究

Objective To evaluate the antituberculous activities of Huangkuisu (HISS). Meth-ods lOStandard human strains of mycobacterium tuberculosis (H37RV) and multi-drug resistant TBstrainswere inoculated in different concentrations of HISS, blank control and positive TB drug culture medium[()observe the growth of mycobacterium tuberculosis and evaluate the antibacterial activity in vitro.②Certain number of standard strains of Mycobacterium tuberculosis H37Rv and drug-resistant strains were injected into the tail vein[()establish a mouse model of mycobacterium tuberculosis infection. The mice were randomly divided into treatment group, rifampicin, HISS treatment group treated lasting for 6 weeks; the control group was given normal saline. The antibacterial activity in vivo were evaluated[()compare the treatment results according[()the pathological changes in lung and spleen tissues (HE staining and acid-fast staining) and charging amount of bacteria. Results lOthe bactreial colonies were grew normally in model group, but were not grew in     

结核分枝杆菌CFP10-ESAT6融合蛋白的真核表达及其牛结核病诊断价值评价

本研究旨在利用毕赤酵母(Pichia pastoris)系统融合表达结核分枝杆菌(Mycobacterium tuberculosis,MTB)的培养滤液蛋白10(culture filter protein 10,CFP10)和早期分泌抗原靶6蛋白(earlier secreted antigen target 6,ESAT6),并评价其作为牛结核病外周血γ-干扰素(interferon gamma,IFN-γ)体外释放实验特异性刺激剂来诊断牛结核病的应用潜能.通过PCR扩增cfp1 0-esat6融合基因,构建pPICZα A-(cfp10-esat6)重组质粒,电转化毕赤酵母GSll5,添加甲醇至终浓度1.0％,诱导3d,取培养上清进行SDS-PAGE分析,镍离子金属螯合亲和层析柱纯化目的蛋白,Western blot分析重组蛋白的免疫反应性;取纯化的融合蛋白CFP10-ESAT6作为刺激剂用于牛结核病外周血IFN-γ体外释放实验,评价其牛结核病诊断价值.结果表明,目的蛋白(33kD)被成功分泌表达,该融合蛋白与抗CFP10、ESAT6、组氨酸标签和c-Myc4种单抗均发生特异性反应,具有较好的免疫反应性.165份奶牛外周血样品的IFN-γ检测结果表明,CFP 10-ESAT6融合蛋白与结核菌素纯蛋白衍生物(purified protein derivative,PPD)作为刺激剂,二者阳性符合率为82.3％,阴性符合率为78.8％.本研究利用酵母表达系统成功表达CFP10-ESAT6融合蛋白,并表现出更高的生物学活性,在牛结核病外周血IFN-γ体外释放实验中可作为候选刺激剂,并能克服混合感染导致的PPD漏检问题,从而进一步提高检测的敏感性和特异性.     

CRISPR/Cas System and Its Application in the Study of Mycobacterium tuberculosis

Clustered regularly interspaced short palindromic repeats (CRISPR) / CRISPR-related protein (Cas) system is a heritable prokaryotic adaptive immune system against invading nucleic acids. It is an editing tool for many organisms that can generate highly specific gene double-strand breaks and repair them by non-homologous end joining (NHEJ) or homologous recombination (HR). Due to the complexity of its genetic manipulation, Mycobacterium tuberculosis genome research has many difficulties. Therefore, the emergence of the CRISPR/Cas system has a milestone significance for the research of Mycobacterium tuberculosis. In this review, we focus on the application of the CRISPR/Cas system in Mycobacterium tuberculosis and summarizes the present research progress in order to provide a reference for the selection of Mycobacterium tuberculosis research methods.     

Examination and control of lameness in dairy herds

Extract

Lameness is a significant problem in dairy herds in New Zealand. It affects production and causes cows to lose weight. If antibiotics are used, milk has to be withheld from the vat. Cows may go into extended anoestrus and some which fail to conceive have to be culled. Even in its mildest form lameness is an inconvenience to the normal management of the herd.     

Mange in pigs: A survey

Extract

Mange in pigs caused by Sarcoptes scabiei var. suis is reported to be common in New Zealand, but, to the writer's knowledge, no investigation has been made of the number of infested farms in any area.