水貂细菌性疾病的病原学调查

为调查山东省水貂常发细菌病的病原学资料,分别对患病水貂进行了病理剖检、细菌的纯培养和生化鉴定。经分离鉴定确定致病菌的种类为变形杆菌、大肠杆菌、沙门氏菌、克雷伯氏菌、耶尔森氏菌、葡萄球菌和绿脓杆菌,并对水貂细菌病的发病原因和规律进行了探讨。     

水貂肝脏中克雷伯氏菌的鉴定

为了检验辽宁省某水貂场患呼吸系统疾病的散发病例是否由肺炎克雷伯氏菌引起,试验采用病理剖检、组织切片、无菌技术分离细菌、分子生物学鉴定等方法对其进行检验。结果表明:通过对患病水貂进行解剖,发现其肺脏有明显出血斑,并伴有坏死灶、钙化灶;组织切片显示,肺泡壁不清,肺脏组织有散在慢性炎性细胞、红细胞;通过无菌技术从肝脏中分离得到一株细菌,经分子生物学鉴定确定其为肺炎克雷伯氏菌。说明水貂所患疾病是由肺炎克雷伯氏菌感染引发的肺炎。     

貂源肺炎克雷伯氏菌的分离与鉴定

2013~2016年山东省、河北省、黑龙江省、吉林省的部分水貂养殖场发生了严重的出血性肺炎,导致水貂大量死亡,为了客观评估水貂出血性肺炎的危害及为综合防控提供参考依据,试验对423个水貂病例样本进行分离鉴定并且对所分离的细菌进行了形态特征观察、16SrRNA基因测序、血清型鉴定、小鼠毒力试验测定、生化试验鉴定及药敏试验测定。结果表明:423个样本中分离到68株肺炎克雷伯氏菌,其中最为流行的血清型为K2型(35株);并筛选出4株菌株对小鼠有很强毒力性;生化试验结果表明同一血清型的不同菌株之间也存在明显差异;药敏试验结果表明,4株K2型肺炎克雷伯氏菌强毒菌株对氧氟沙星、阿米卡星2种抗生素均为敏感或介于中间;对强力霉素、环丙沙星等8种抗生素均耐药;对诺氟沙星、庆大霉素等4种抗生素均为耐药或介于中间。     

水貂大肠埃希氏菌病的诊治试验

通过对患病水貂进行病理剖检,细菌纯培养,病毒检测,生化鉴定,确定是水貂大肠埃希氏菌病。再应用多种抗生素作药敏试验,筛选出了高度敏感的抗菌药。并对山东省威海地区水貂大肠埃希氏菌病的发生规律进行了探讨。     

奶牛流产胎儿及阴道分泌物病原菌的检测和药物敏感性分析

调查北京地区7个奶牛场奶牛流产的发病原因,采集流产胎儿及恶露不尽母牛的阴道分泌物进行细菌分离鉴定、致病性及中西药的药敏试验,并测定中药的MIC和MBC。共分离出9种42株细菌,其中金黄色葡萄球菌11株、腐生葡萄球菌6株、表皮葡萄球菌2株、变形菌属5株、克雷伯氏菌属3株、埃希氏菌属2株、蜡样菌属3株、黏液奈瑟氏菌属4株、浅黄奈瑟氏菌属2株、其他未鉴定出种属的菌4株;其中,葡萄球菌占45.2%、杆菌占23.8%、其他革兰氏阴性菌占31.0%。通过致病性试验,有28株为致病菌。对其中几种分离菌进行了25种常用抗生素、7种中药及一个复方的体外抑菌试验,结果表明,这些菌对多数抗生素有耐药性,如青霉素和链霉素,大多数革兰氏阴性菌对喹诺酮类药物比较敏感,头孢菌素类药物则对革兰氏阳性菌有较好的抑制效果,中药金银花和瓜蒌对这些菌的体外抑菌作用较好。     

水貂细菌病的药敏试验和防治

据海关贸易总署统计,全国平均年产水貂皮1200万张,山东省占2／3。养殖水貂的利润很高,是农民脱贫致富的有效途径,深受农民的欢迎。近年来,对水貂病毒性疾病研究较为深入,并且已经得到一定的控制,而对水貂细菌性疾病的相关研究报道则很少。由于养殖水貂的规模不断扩大,水貂抗病力逐年降低,条件性致病菌是继发水貂细菌病的主要病原,给水貂的养殖业带来巨大的经济损失,也制约了水貂养殖业的进一步发展。为了调查山东省水貂常发细菌病的耐药情况,笔者分别对病貂体内细菌进行了分离鉴定,确定致病菌的种类是：变形杆菌、大肠杆菌、沙门氏菌、克雷伯氏菌、耶尔森氏菌、葡萄球菌和绿脓杆菌。并对上述细菌分别用24种抗菌药物进行了药敏试验,确定水貂细菌的耐药情况,并分析了细菌感染的防治方法。     

一例水貂感染蜂房哈夫尼菌的分离鉴定及药敏试验

为了对某发病水貂场的病死水貂进行病原学诊断,采用病原分离、生化试验、PCR扩增、基因序列比对等方法对分离细菌进行了鉴定,最终确定其病因为蜂房哈夫尼菌感染。在此基础上进行了药敏试验,发现蜂房哈夫尼菌对大多数药物敏感。     

水貂源致病性黏质沙雷氏菌的分离鉴定与遗传进化分析

为确定水貂黏质沙雷氏菌的耐药状况、致病性及其遗传特征,本研究从黑龙江省患病死亡水貂中分离得到3株细菌,根据其形态特征、培养特性、生化试验及16S rRNA序列测定对分离菌进行鉴定;随后用K-B法测试分离株对常见的24种抗菌药的敏感性,并进行了致病性试验和遗传进化分析。结果显示,分离菌为黏质沙雷氏菌,对多种常用抗菌药物具有高度耐药性;可引起试验组小鼠100%死亡;分离株与来自活性污泥与火山堆积物环境的菌株遗传亲缘性最近。表明黑龙江省水貂中存在黏质沙雷氏菌的感染,分离株耐药现象较严重并具有很强的致病性,同时提示该菌株可能来源于环境中。本试验从水貂中分离得到致病性黏质沙雷氏菌为首次报道,研究结果可作为该菌感染水貂导致相关疾病的检测、鉴别和预防依据。     

1株兔源奈瑟菌的分离与鉴定

<正>奈瑟菌属(Neisseriaceae)是革兰阴性菌。根据DNA同源性的分析,目前已知的有脑膜炎奈瑟菌(N.Meningitidis)、淋病奈瑟菌(N.gonorrhoeae)、干燥奈瑟菌(N.sicca)、微黄奈瑟菌(N.sunflava)、浅黄奈瑟菌(N.flavescens)和黏液奈瑟菌(N.mucosa)等[1],共12种人源奈瑟菌。其中最重要的致病菌是寄生的脑膜炎奈瑟球菌和淋病奈瑟球菌。其他均为     

水貂肺炎克雷伯菌感染的诊断与药敏试验

为了对某水貂场的水貂出血性肺炎进行诊断,通过病原分离、生化试验、16SrRNA的PCR扩增分析的方法对细菌进行鉴定,确定为肺炎克雷伯菌感染。药敏试验显示分离菌对氨苄西林、卡那霉素、林可霉素、四环素等药物耐药。     

淋球菌孔蛋白基因与脂寡糖表位融合基因原核表达载体的构建及表达

PCR扩增淋球菌CMCC29400、CMCC29403株孔蛋白(PI)A、B及表位基因,使用linker GSGGSG并通过重叠PCR法将表位基因连接在PIA、PIB上形成融合基因PIA-表位、PIB-表位,分别与克隆栽体pMD-18T连接,测序正确后将目的基因插入表达载体pET32a(+)中,构建pET32a-PIA...     

Aerobic bacterial flora of the nasal cavity in Gulf of California sea lion (Zalophus californianus) pups

Nasal swab samples from clinically healthy California sea lions pups (Zalophus californianus) from six different reproductive rookeries in the Gulf of California were collected to determine the type and frequency of the representative aerobic bacterial microflora of their nasal mucosa. A total of 114 samples were examined and 100 bacterial isolates were identified and typified by microbiological and biochemical standard tests. Fifty four isolates corresponded to Gram positive bacteria (54%) and 46 isolates to Gram negative bacteria (46%). Fifteen bacterial genera were identified, including Micrococcus, Arcanobacterium, Corynebacterium, Moraxella, Neisseria, Escherichia, Kurthia, Acinetobacter, Staphylococcus, Brevibacillus, Bacillus, Klebsiella, Stenotrophomonas, Pseudomonas and Aeromonas. The most frequently isolated genera were Moraxella (24%), Micrococcus (18%), and Corynebacterium (15%). These results show the presence in the nasal cavity of sea lions of several microorganisms. Although considered part of the normal microflora, they may also be opportunistic pathogens for their hosts and may act as a potential natural sentinel of environmental changes.     

Isolation of Neisseria cuniculi from a case of ovine pneumonia

Neisseria cuniculi was isolated in pure culture from the lungs of a 2-month-old pneumonic lamb. Mouse LD50, evaluated by intraperitoneal and pulmonary inoculation of the microorganism, was 2 X 10(7) colony-forming units in both cases. The role of the organism in pathogenesis of the disease could not be determined. This organism has not previously been reported in sheep.     

脑膜炎球菌外膜蛋白NhhA的表达及免疫效果评价

NhhA是在对脑膜炎球菌MC58株进行全基因组测序过程中发现的膜表面蛋白质,属于三聚体自体转运黏附素家族,介导细菌黏附于宿主鼻黏膜上皮细胞。为了对NhhA在小鼠体内诱生体液免疫效果进行评价,将截去信号肽编码序列的目的基因克隆到原核表达载体pET-21b(+)上,3′端与6×His标签融合表达,用Ni柱螯合层析法纯化目的蛋白,并用脑膜炎球菌A、B、C、W135、Y群的混合免疫血清对重组目的蛋白进行免疫印迹鉴定,结果均呈阳性反应。以Al(OH)3和CpG作为NhhA的佐剂免疫Balb/c小鼠,二次免疫后采血进行ELISA检测,其血清抗体滴度高达1∶100 000。用脑膜炎球菌裂解物鉴定免疫血清的特异性,结果显示为阳性。     

Isolation of Mycoplasma bovoculi from cases of infectious bovine keratoconjunctivitis.

Five outbreaks of infectious bovine keratoconjunctivitis were examined for bacteria and mycoplasmas. Mycoplasma bovoculi was demonstrated in four of the five outbreaks. Other mycoplasmatales were represented by Ureaplasma in one sample. Moraxella bovis and Neisseria ovis were found in all the outbreaks, the former being present in the vast majority of the animals. Transmission experiments with Mycoplasma bovoculi and Moraxella bovis in combination were carried out on four young, colostrumdeprived calves. Mycoplasma bovoculi appeared to have an enhancing effect on the pathogenicity of Moraxella bovis.     

The effect of Pasteurella haemolytica and the leukotoxin of Pasteurella haemolytica on bovine lung explants.

Bovine lung explants were used in a study designed to compare the pathogenic effects of Pasteurella haemolytica type 1, a nonpathogenic organism Neisseria subflava, or the crude leukotoxin of P. haemolytica on alveolar macrophages and lung parenchymal cells. Concentrated, purified peripheral blood neutrophil suspensions were added with the bacteria to some explants. Duplicate pairs of cultures from each treatment group were fixed at regular intervals up to 24 hours after seeding and morphological changes were assessed by light and electron microscopy. Pasteurella haemolytica caused deterioration of alveolar macrophages within one hour but did not affect parenchymal cells for more than 12 hours. Neisseria subflava did not affect alveolar macrophages initially, but caused an accelerated deterioration after four hours. After 24 hours, bacterial overgrowth caused similar deterioration of all cells in explants seeded with either bacterium. Alveolar macrophages phagocytosed large numbers of N. subflava but rarely ingested P. haemolytica. Added neutrophils did not have any discernible effect on any of the explants and did not potentiate bacterial effects. Addition of crude leukotoxin of P. haemolytica to the culture medium significantly accelerated alveolar macrophage deterioration without apparent effect on parenchymal cell survival. These results support the hypothesis that the severe tissue destruction of fulminant pneumonic pasteurellosis is not a direct result of bacterial infection.     

Infectious bovine keratoconjunctivitis and lymphofollicular hyperplasia of the third eyelid in heifers

On a dairy cattle farm, infectious bovine keratoconjunctivitis was diagnosed in 29 (24%) calves and heifers aged from 2 weeks to 1 year old. The highest infection rate (18%) occurred in animals aged 3-6 months. The bacteriological examination of swabs from the affected animals yielded several species of bacteria: Moraxella bovis, Neisseria ovis, N. cuniculi, plasma coagulase-negative Staphylococcus spp., alpha-haemolytic Streptococcus spp., Arcanobacterium pyogenes and Escherichia coli. Moraxella bovis and N. ovis were the most common isolates. Hyperplasia of the lymphatic tissue of the third eyelid in the form of nodules 7-8 mm in diameter was diagnosed in two heifers aged 8 and 10 months.     

Mycoplasma and Associated Bacteria Isolated from Ovine Pink-eye

A mycoplasma was recovered from the untreated conjunctival membranes of nine sheep affected by Pink-eye. It was neither isolated from the conjunctiva of treated animals which were affected nor from the conjunctiva of normal animals either in contact or not in contact with affected animals.

Bacteria found on normal conjunctival membranes were Neisseria ovis, Escherichia coli, Staphylococcus epidermididis, Streptococcus and Bacillus spp.

Bacteria found in clinical cases of Pink-eye were N. ovis, E. coli, a Streptococcus and Pseudomonas spp.

     

细菌重组减毒鼠伤寒沙门氏菌疫苗研究进展

鼠伤寒沙门氏菌 ( St)是一种肠道致病菌 ,通过基因突变可构建许多鼠伤寒沙门氏菌减毒株 ,例如 :X40 72、X42 17、X45 5 0、X4989、X4990、 X40 64、 SL 3 2 61、 GID10 1、 GID10 5、GID10 6和 BRD5 0 9等 ,它们均是两个或多个基因的精确突变 ,其基因型和表型均很稳定 ,可用作构建细菌性疫苗的表达载体。国内外学者相继研制了肺炎链球菌、结核杆菌、百日咳杆菌、产单核细胞李斯特菌、鼠疫耶尔森菌、土拉弗郎西斯菌、铜绿假单胞菌、淋病奈瑟菌、牛布氏杆菌、破伤风梭菌、炭疽芽孢杆菌、沙眼衣原体和猪肺炎支原体等细菌的重组减毒鼠伤寒沙门氏菌疫苗。文章着重讨论了这些疫苗的构建及其免疫机制等方面的研究进展 ,从而为新型菌苗的研制提供一种新的思路     

A microbiological study of pneumonic calf lungs.

BITSCH, V., N. F. FRIIS and H. V. KROGH: A microbiological study of pneumonic calf lungs. Acta vet. scand. 1976, 17, 32–42.–Fifty pneumonic calf lungs were subjected to microbiologic screening with regard to bacteria, mycoplasmas, and viruses.Of bacteria the species most commonly found were Pasteurella multocida (eight lungs), Pasteurella hemolytica (eight lungs), and Corynebacterium pyogenes (13 lungs). Of special interest was the demonstration of Neisseria spp. in five lungs. Mycoplasma dispar was found in 31 lungs, Mycoplasma bovirhinis in 16 lungs, and Urea-plasma in 26 lungs. Cytopathogenic agents were demonstrated in 14 lungs. Four isolates were found to be bovine respiratory syncytial virus, three were bovine viral diarrhea virus, and two were bovine parainfluenza 3 virus. The remaining five cytopathogenic agents were not identified.