仔猪水肿病病原菌的分离鉴定

从某猪场发生水肿病仔猪的脾脏中分离到一种细菌,通过菌体形态,菌落形态,染色特性,培养特性,生化试验等一系列的系统鉴定,确定为引起仔猪水肿病的大肠埃希氏菌.动物致病性试验表明该菌对小白鼠有较强的致病性,引起小白鼠死亡.毒素试验证明该菌产生致水肿病2型类志贺毒素(SIT-2e),引起小白鼠发生水肿症状,该毒素对Vero细胞敏感,引起其死亡.药敏试验证明该菌对常见的抗生素不敏感.     

仔猪水肿病病原菌的分离鉴定

从某猪场发生水肿病仔猪的脾脏中分离到一种细菌，通过菌体形态，菌落形态，染色特性，培养特性，生化试验等一系列的系统鉴定，确定为引起仔猪水肿病的大肠埃希氏菌，动物致病性试验表明该菌对小白鼠有较强的致病性，引起小白鼠死亡，毒素试验证明该菌产生致水肿病2型类志贺毒素（SLT－2e)，引起小白鼠发生水肿症状，该毒素对Vero细胞敏感，引起其死亡，药敏试验证明该菌对常见的抗生素不敏感。     

新疆和田地区羊源绿脓杆菌的分离鉴定与药敏试验

为了解新疆和田地区某规模化羊场羔羊腹泻病例主要感染的病原菌及其耐药情况,试验采集腹泻羔羊肛拭子进行细菌的分离培养、革兰氏染色,挑取纯化后的单菌落进行生化鉴定和16S rRNA基因鉴定,并对分离菌株进行药敏试验和小鼠致病性试验。结果表明：分离菌株革兰氏染色镜检可见单个存在或成对排列的革兰氏阴性短杆菌,结合生化试验结果初步鉴定为绿脓杆菌,命名为6f。该菌株16S rRNA序列在NCBI中进行BLAST比对发现,与绿脓杆菌菌株核苷酸相似性达到100%,高度同源,最终鉴定分离菌株6f为绿脓杆菌。分离菌株6f对头孢拉定、卡那霉素、氨苄西林等14种抗生素高度敏感,对头孢他啶、多黏菌素B中度敏感,对青霉素、克林霉素、麦迪霉素、万古霉素耐药。分离菌株6f对小鼠具有强致病性。说明引起该规模化羊场羔羊腹泻的病原菌是绿脓杆菌,该菌对大多数抗生素敏感。     

规模化羊场B型产气荚膜梭菌分离鉴定及生物学特性检测

2016年,山东某规模化羊场新生羔羊暴发腹泻,并伴急性毒血现象,出现部分死亡个例。对该羊场的病死羔羊进行剖检,分离4株特征病原菌(分别命名为Cp1、Cp2、Cp3、Cp4),对病菌的形态特点、生化特性以及毒素基因序列进行PCR检测,最终确定病原菌为产气荚膜梭菌。PCR检测结果显示该菌的毒素基因有α毒素、β毒素和ε毒素;毒素毒力试验表明,产气荚膜梭菌毒素对小鼠有强致病性,并证明产气荚膜梭菌通过释放毒素致病而本身并不具有致病性;药敏试验发现,分离菌对青霉素、四环素、庆大霉素、复方新诺明和强力霉素的耐药率极高,可达85%以上,而对头孢噻肟、氯霉素、氟苯尼考、链霉素和恩诺沙星等有较强的敏感性;结合传统免疫措施配合抗生素药物的治疗,可一定程度控制该病的流行。本试验结果为羊B型产气荚膜梭菌病的防治提供了试验依据。     

一株羊源致病性大肠杆菌分离鉴定

为了研究齐齐哈尔市周边某羊场羔羊发生腹泻的原因,通过对1例腹泻羔羊的粪便进行细菌分离鉴定、生化试验、K-B试纸法进行药物敏感性试验、菌体16S rDNA序列鉴定、动物致病性试验、耐药基因检测。结果从羔羊粪便中分离出一株细菌,菌落形态和生化试验结果与大肠杆菌相符,药物敏感性试验显示对头孢噻肟、头孢他定耐药,对四环素、环丙沙星中介,对阿米卡星、庆大霉素、氨苄西林敏感。扩增的16S rDNA序列片段大小约1 500 bp,与GenBank对比显示和序列号为NC＿054923.1的大肠杆菌同源性高达99.15%,将细菌接种于小白鼠体内24 h全部死亡,并检测到该大肠杆菌携带EBC耐药基因。为齐齐哈尔市羊源致病性大肠杆菌的研究提供了一定的依据。     

羔羊腹泻病的微生物学诊断及防治

从陕西某羊场腹泻羊的粪便中,无菌操作采取样品3份,2～4 h送实验室进行微生物学诊断,从中分离出1株革兰阴性中等大小杆,经生物学特性试验和生理生化试验鉴定,该分离到的细菌为致病性大肠埃希氏菌,血清学鉴定为O114型.药敏试验结果表明,对氨曲南、大观霉素、头孢噻肟高度敏感;对米诺环素、克林霉素、克拉霉素有耐药性.24 h肉汤培养物对小白鼠有致死性,外毒素0.2 mL对小白鼠尾静脉注射有致死性.绵羊血琼脂平板呈β溶血.     

羊奇异变形杆菌的分离鉴定及药敏试验

为查明宁夏地区某羊场羔羊腹泻的发病原因并选择敏感药物用于治疗,从患病羔羊粪便中分离出4株细菌,进行形态特征、培养特性、16S rRNA测序、VITEK微生物鉴定系统鉴定、致病性试验及药敏试验。结果显示,分离菌为奇异变形杆菌。动物试验表明,4株奇异变形杆菌对小鼠具有很强的致病性。药敏试验表明,4株奇异变形杆菌对氨基糖甙类抗生素(阿米卡星、卡那霉素、链霉素)、氟苯尼考及头孢菌素类抗生素敏感,而对大环内酯类(红霉素和克林霉素)、复方新诺明、恩诺沙星全部耐药。对青霉素类(哌拉西林、氨苄西林、阿莫西林)、喹诺酮类(环丙沙星、氧氟沙星、诺氟沙星)、四环素、万古霉素、庆大霉素呈现不同程度的耐药。结果表明,该4株奇异变形杆菌具有较强的致病力和多重耐药性,可能是此次羔羊腹泻的致病菌,治疗首选氨基糖甙类、氟苯尼考及头孢菌素类抗生素。     

致仔猪水肿病大肠杆菌的分离、鉴定及药敏试验

从发生水肿病的仔猪脏器中分离的细菌,通过茵体形态、革兰氏染色特性、生化特性等一系列的 鉴定,确定为大肠埃希氏茵.动物致病性试验表明,该茵对小鼠有较强的致病性,可引起小鼠死亡.药敏试验证明,该茵对诺氟沙星、环丙沙星、卡那霉素、氯霉素和庆大霉素较敏感.     

猪链球菌2型的分离鉴定及免疫预防

从某猪场分离到一株细菌,通过培养特性、菌体形态、菌落形态、染色特性、生化试验及血清学试验等一系列的系统鉴定,确定为猪链球菌2型。动物致病性试验表明该菌对小白鼠和仔猪有较强的致病性,引起其死亡。药敏试验证明该菌对青霉素、氯霉素等高度敏感,对头孢拉定、卡那霉素等中度敏感,对氟派酸等不敏感。分离菌制成油佐剂灭活苗能有效的预防该猪场猪群的发病。     

致羔羊脑炎粪肠球菌的分离鉴定

为确定某羊场导致羔羊脑炎的病原,对从3只病死羔羊脑、肝、脾、淋巴结等组织中分离到革兰阳性球菌,采用生化试验、PCR检测、16SrRNA序列分析、进化树分析、药物敏感性及小鼠致病性测定进行鉴定。结果表明,分离菌符合粪肠球菌的生物学特性;对小鼠致病性较强;对庆大霉素、红霉素、克林霉素、万古霉素等有较强的耐药性,对呋喃妥因极敏感,对青霉素、氨苄西林、环丙沙星等敏感;应用DNA Man软件对分离株WS1、WS2、WS3、WS4、WS5 16SrRNA基因序列进行同源性比对,结果与GenBank数据库中粪肠球菌(NR-040789.1)的同源性分别为99.2%、99.0%、98.5%、98.5%和98.8%;经MEGA4.0软件分析的分子系统进化树(N-J法)表明5株分离菌与粪肠球菌之间的亲缘性最近。说明该羊场导致羔羊脑炎并死亡的病原为粪肠球菌。     

Colibacillosis in neonatal lambs: onset of diarrheal disease and isolation and characterization of enterotoxigenic Escherichia coli from enteric and septicemic forms of the disease.

A lamb ligated intestinal segment (LIS) test was adapted to determine the enterotoxigenicity of Escherichia coli isolates obtained from fecal and blood specimens from neonatal lambs with overt diarrheal disease. The lamb LIS was distended by 28 of 80 (37%) isolates from fecal specimens from 23 affected lambs. Enterotoxigenic E coli isolations were made from 10 of the 23 lambs examined. Isolates of E coli were made from the blood of 17 of 76 (22%) animals with severe diarrheal disease. Distention of the lamb LIS was caused by 3 of 39 (7.7%) isolates from 2 of 17 lambs with E coli septicemia. All lambs (n = 266) that were born during a 4-day period in an intensified shed lambing operation and that were not given prophylactic antibiotic therapy developed diarrheal disease within 28 hours of birth. Signs of enteric disease appeared in lambs born during inclement weather in a significantly (P less than 0.001) shorter period than in those born during mild weather conditions.     

一株致梅花鹿猝死症A型产气荚膜梭菌的分离与基因分型研究

对苏州某梅花鹿场 1头猝死梅花鹿进行了病原的分离与鉴定 ,在死亡鹿体内分离到 1株G+ 、无芽孢、有荚膜、粗大正直的杆菌。通过肠内容物毒素中和试验和多重PCR方法证明所分离到的细菌为A型产气荚膜梭菌。结合流行病学、临床症状和病理变化 ,证实A型产气荚膜梭菌为引起此例梅花鹿猝死症的病原     

羊传染性脓疱病毒的分离与鉴定

对采自松原市的疑似羊接触传染性脓疱性皮炎的羔羊病料,用犊牛睾丸原代细胞进行病毒分离培养,观察细胞病变;将出现病变的病毒细胞培养液接种家免和羔羊后,出现典型羊接触传染性脓疱性皮炎的临床症状;对病毒细胞培养液的电镜观察,发现了副痘病毒,证明确为羊传染性脓疤性病毒。     

唇乳突丝虫感染蚴接种非固有宿主动物致发脑脊髓丝虫病研究

用东乡伊蚊叮吮含有唇乳突丝虫微丝蚴的模型动物——小鼠血液,待微丝蚴在蚊体内发育至感染期时,分离出感染坳,皮下多点接种43只昆明小鼠(每只15～200条)、1只山羊及2只绵羊(每只200～300条)和4匹驹(每匹750～1 250条);将指状丝虫接种到20只昆明鼠体内,比较两种虫体的致病性。结果:唇乳突丝虫感染鼠有16只经1～8 d潜伏期发病,呈现瘫痪、昏迷症状后死亡.实验羊和驹经5～21d潜伏期后均呈不同程度的运动和神经症状,于接种虫体后40～140 d扑杀.经病理学观察,3种动物脑脊髓均呈现虫伤性液化坏死灶及非化脓性脑脊髓炎变化,在其中枢神经系统组织切片中发现丝虫虫体断面或钙化碎片,从而证明唇乳突丝虫可人工感染昆明小鼠、羊、驹发生脑脊髓丝虫病,进而提出该虫可以成为马、羊脑脊髓丝虫病的病原之一。指状丝虫感染鼠死亡率高于唇乳突丝虫感染鼠(P<0.01),初步认为唇乳突丝虫致病性较指状丝虫弱。     

一株山羊魏氏梭菌的分离鉴定及其致病性研究

本试验从一例病死山羊组织内分离到一株致病性细菌,通过鉴别培养、生化试验、分子生物学试验和动物致病性试验,证明该病原菌为羊致病性A型魏氏梭菌;毒素基因分析结果显示,该菌同时含有α和β2两种毒素基因;动物致病性试验结果表明,该菌对昆明小鼠具有较强的致病性,并从试验致死的昆明小鼠病料中分离到了与病死山羊病原相一致的细菌,从而确定A型魏氏梭菌为引起该山羊死亡的主要病原菌。本试验结果为该羊场魏氏梭菌病的治疗和预防提供了科学依据。     

Isolation,Identification and Pathogenicity Research of a Strain of Clostridium perfringens from Goat

A pathogenic bacteria was isolated from a dead goat,and it was identified as goat-pathogenic type A Clostridium perfringens by differential culture,biochemical test,molecular biological technology and animal pathogenicity test.Analysis results of toxin genes showed that this bacteria contained both α and β2 toxin genes.Animal pathogenicity test result showed that this bacteria was highly pathogenic to mice,and the same bacteria was isolated from dead mice as which was isolated from the dead goat,so it was certain that type A Clostridium perfringens was the main pathogenic bacteria which caused the goat dead.The results would provide scientific basis for the treatment and prevention of the disease caused by Clostridium perfringens in this goat farm.     

Isolation,Identification, 16S rRNA Gene Sequencing and Genetic Evolution Analysis of Aeromonas aeruginosa from Duck

【Objective】 The experiment was aimed to study the pathogenic bacteria of acute death of ducklings in a duck farm in Henan province and its phylogenetic status.【Method】 The liver and spleen of dead ducks in the diseased duck farm were collected.The bacterial morphology, Gram-staining, biochemical characteristics, sequence analysis of 16S rRNA gene, drug sensitivity test and pathogenicity test were carried out.【Results】 The isolated bacteria grew on blood agar medium with smooth, convex, milky white and α-hemolytic Gram-positive cocci.Biochemical test results showed that the isolated bacteria were positive for maltose, sucrose, raffinose, nitrate reduction reaction, MP-VP test, urea, lysine decarboxylase, ornithine decarboxylase and aescin, and negative for xylose, lactose, glucose, sorbitol, hydrogen sulfide, citrate, peptone, mannitol, phenylalanine and methyl red.The results of 16S rRNA gene sequencing and BLAST comparison results showed that the 16S rRNA gene sequence of the isolated strain was 94.8%-99.9% similar to that of Aerococcus viridans published on NCBI, and the similarity with strains Mnlv1, Mnlv2 and W66 was the highest, up to 99.9%.The similarity with strain GXBl-1 was the lowest, which was 94.8%.Phylogenetic tree analysis showed that the isolated bacteria belonged to the same genus and group on the same branch as strains of Aerococcus viridans FL09, 15MS and Mnlv2 etc., and had the closest genetic relationship with FL09.The results of drug sensitivity showed that the isolated strain was sensitive to fosfomycin, ampicillin and amoxicillin, moderately sensitive to penicillin, neomycin and amikacin, it was resistant to rifampicin, neomycin, bacitracin, erythromycin and enrofloxacin.The results of pathogenicity test showed that the strain was lethal and increased with the increase of inoculation concentration.【Conclusion】 This study determined that the pathogen causing the acute death of ducklings in a duck farm in Henan province was Aerococcus viridans, which provided a reference basis for clinical diagnosis and treatment of the diseases caused by this bacteria.     

亚洲黑熊源阴沟肠杆菌的分离鉴定及耐药性分析

为明确贵阳市某公园动物园1只亚洲黑熊死亡的原因,本试验采集死亡黑熊内脏器官,进行细菌分离培养、菌体形态观察、生理生化鉴定、16S rRNA基因序列分析和小鼠感染试验。结果显示,从死亡黑熊肺脏样本分离出一种圆形、凸起、表面光滑、边缘整齐、中等大小的乳白色菌落,经染色镜检为呈单在或双排列的革兰氏阴性小杆菌。该分离菌可利用葡萄糖、蔗糖、甘露醇、山梨醇和枸橼酸盐,不发酵乳糖,不产生硫化氢,精氨酸脱羧酶阳性,赖氨酸脱羧酶阴性,符合阴沟肠杆菌生化特征。经细菌16S rRNA通用引物扩增,可得到大小为1 419 bp的片段,与NCBI上相应序列进行BLAST比对,结果显示与阴沟肠杆菌序列相似度达99.9%,确认该分离菌为阴沟肠杆菌。用该分离菌腹腔接种小鼠,可致死小鼠,半数致死量（LD₅₀）为7.94×10⁸ CFU/mL。药敏试验发现,该分离菌对丁胺卡那霉素、氧氟沙星、诺氟沙星和环丙沙星等常用抗菌药均保持较高的敏感性。本试验结果表明,阴沟肠杆菌是导致该亚洲黑熊死亡的病原。     

仓鼠致病性大肠杆菌的分离鉴定及药敏试验

为探讨长春地区某仓鼠饲养场中仓鼠急性死亡的原因及应对该突发性疾病,对死亡仓鼠进行实验室检查并分离得到1株细菌,通过对该分离株进行形态学观察、培养特性观察、生化试验、小鼠致病性试验、PCR鉴定和23SrRNA基因同源性分析,判定该分离菌为1株高致病性大肠杆菌。该菌可致仓鼠突发急性致死性大肠杆菌病,死亡率达到100%,死亡小鼠出现胃肠道极度膨胀的典型症状。药敏试验结果表明,该大肠杆菌对多种抗生素敏感,但对四环素类抗生素及复方新诺明(SXT)有很强的耐药性,可用庆大霉素进行治疗。研究结果为探讨急性大肠杆菌病的发病机制及其防治提供了理论基础。     

鹿“猝死症”病因的调查

采取现场查询、病因学等调查方法,对１９９２～１９９７年吉林省、辽宁省、山东省及黑龙江省２７个鹿场鹿“猝死”病因进行调查。结果表明,鹿“猝死”主要是由多种细菌感染所致,占总分离数的７７４％,但主要致病菌为多杀性巴氏杆菌,占总分离数的３７３％;其次是魏氏梭菌,占２３５％;其他细菌分离数占２３５％;缺硒性猝死占８８％;不明原因的猝死占１０８％;发霉饲料中毒猝死占２９％。