一株鸡毒支原体致病性研究与药敏试验

为进一步掌握鸡毒支原体的致病性,从某养殖场分离一种鸡毒支原体的毒株,开展致病性试验和药敏试验。选择使用20枚孵化5日龄的SPF鸡胚,使用2种不同浓度的菌液进行攻毒试验,观察鸡胚的死亡情况和解剖情况,并按照支原体培养方法分离得到病原后进行常规药敏试验,确定哪种抗生素对支原体敏感。研究结果表明,不同浓度均会造成鸡胚死亡,低浓度鸡胚死亡率70%左右,高浓度造成鸡胚全部死亡。分离得到的毒支原体对盐酸沃尼妙林、盐湖索酸泰妙菌素、强力霉素敏感性最强,其次是盐酸大观霉素、水溶性氟苯尼考、酒石酸泰乐菌素。研究结果可知,分离得到的一株鸡毒支原体的致病性较强,同时分离出的高敏药物对支原体具有很强的抑制作用。     

鸡几种致病菌对19种抗菌药物的药敏性试验

随着养禽业的发展,据养禽场反映,很多抗菌药物对细菌病的防治效果不佳,甚至无效。为了给养禽场的兽医临床选择药物提供参考,自１９９６年下半年至１９９７年初,我们对广州、深圳、惠州、新兴、三水、清远、增城、花都、东莞、开平等地养鸡场进行调查,并从中分离了鸡...     

壮观霉素对体外鸡毒支原体的抑菌试验和对鸡体内鸡毒支原体病的治疗试验

1　材料与方法1 .1　试验药物　壮观霉素为水溶性粉剂 ,批号940 71 2 ,由中国医学科学院医药生物技术研究所北抗药厂生产。对照药物壮观霉素 ,水溶性粉剂 ,由比利时生产 ,批号 573KS,由中国医学科学院医药生物技术研究所提供。1 .2　鸡毒支原体菌种　 R株、S6株 ,均由中国兽医药品监察所保存。1 .3　试验鸡　 9日龄北京白鸡 ,试验前经血清学检测 ,该鸡为鸡毒支原体血清学阴性反应。1 .4　鸡毒支原体血清平板凝集抗原　由中国兽医药品监察所生产 ,批号为 930 1。1 .5　抑菌试验　试验前将试验药壮观霉素用蒸馏水配成一定浓度的溶液过滤除菌…     

6种常用抗菌药物对鸡毒支原体的药物敏感性试验

鸡毒支原体(MG)是一种严重危害养禽业的病原体,可引起鸡的慢性呼吸道病(CRD),其特征性症状是呼吸啰音、咳嗽、气管炎、气囊炎、流眼泪等[1].     

抗菌药物的药敏试验方法

1药敏纸片法药敏纸片法是最常用的一种试验方法,能直接体现出抗菌药物的抗菌效用,其优点是:直观明显、对比鲜明,有一定的实验依据。缺点是:仅表现体外抗菌效果,由于抗菌药物在体内受体液环境、代谢分布、组织扩散浓度、半衰期等因素的影响,个别药物并不能真实反应出实际的抗菌疗效。下面介绍抗菌药物的药敏纸片法。1.1药敏纸片的制作方法将要试验的抗菌药物按其有效浓度稀释成1mL备用,脂溶性的抗菌药物使用乙醇或丙酮溶解。用打孔器将滤纸打成6mm直径的圆片100张高压灭菌,加入到抗菌药物有效浓度1mL稀释液中充分混合,阴凉处干燥备用。多种…     

鸡源大肠杆菌、支原体对几种抗菌药物的耐药性调查

从广东省部分规模化养殖场采集、鉴定出154株鸡大肠杆菌、20株鸡毒支原体,采用微量肉汤二倍稀释法测定阿莫西林、环丙沙星、阿米卡星及罗红霉素的最小抑菌浓度(MIC),并与质控菌株的MIC比较。结果表明,鸡大肠杆菌对阿莫西林耐药率最高,其次为环丙沙星,对阿米卡星的耐药率最低;鸡毒支原体对环丙沙星的耐药率最高,罗红霉素次之,对阿米卡星完全敏感。     

甲磺酸培氟沙星对体外鸡毒支原体的抑菌试验和对鸡毒支原体病的治疗 …

利用甲磺酸培氟沙星水溶性粉剂对鸡毒支原体分别进行体内外的抑菌治疗试验。体外抑菌试验结果表明：该药物能有效地抑制试管中鸡毒支原体的生长繁殖。体内试验结果表明：当饮水中药物浓度达到１００ｍｇ／Ｌ时,能有效地防止由于鸡毒支原体引起的死亡;当饮水中药物浓度达到５０ｍｇ／Ｌ以上时,能明显地减轻以至部分消除鸡毒支原体强毒引起的气囊损伤;和感染不对照组相比,该药物能提高鸡体增重;用甲磺酸培氟沙星治疗,能抑制感染     

甲磺酸培氟沙星对体外鸡毒支原体的抑菌试验和对鸡毒支原体病的治疗试验

利用甲磺酸培氟沙星水溶性粉剂对鸡毒支原体分别进行体内外的抑菌治疗试验。体外抑菌试验结果表明：该药物能有效地抑制试管中鸡毒支原体的生长繁殖。体内试验结果表明：当饮水中药物浓度达到１００ｍｇ／Ｌ时,能有效地防止由于鸡毒支原体引起的死亡;当饮水中药物浓度达到５０ｍｇ／Ｌ以上时,能明显地减轻以至部分消除鸡毒支原体强毒引起的气囊损伤;和感染不治疗对照组相比,该药物能提高鸡体增重;用甲磺酸培氟沙星治疗,能抑制感染鸡体内的鸡毒支原体,从而使部分鸡体内检测不到鸡毒支原体抗体。     

鸡毒支原体的分离鉴定及药敏试验

从云南地区某疑似慢性呼吸道病(CRD)的鸡场分离到1株支原体菌株,经菌落形态观察、血清学鉴定,证明该分离株为鸡毒支原体(MG)。     

山东省部分地区鸡大肠杆菌的药敏试验

采集山东部分地区鸡大肠杆菌病病料，分离培养，运用纸片法测定各分离菌株对18种药物的敏感性，并与标准株O1、O2、O78相比较。结果表明，鸡大肠杆菌各分离株对各药物的敏感性不同，且对临床上常用的喹药物具有明显的耐药性，但对氨基糖甙类的丁胺卡那霉素比较敏感。     

Chemotaxis in Mycoplasma gallisepticum

Boyden-type chemotactic chambers were used to demonstrate that Mycoplasma gallisepticum (MG) was capable of migrating into chemotactic membranes. Scanning electron microscopy was used to confirm that MG could penetrate the membranes. To further demonstrate the invasive ability of MG, MG was deposited on the shell membranes of 9-day-old chicken embryos, and after 6 days of incubation, the presence of MG DNA in the allantoic fluids was detected by polymerase chain reactions. These results indicate that MG can penetrate cellular membrane, possibly by going through the porous cellular surface.     

Immunogenicity of Mycoplasma gallisepticum

The serological response and protective immunity elicited in the chicken by the pathogenic Ap3AS strain and the moderately pathogenic 80083 strain of Mycoplasma gallisepticum and variants of strain 80083 attenuated by repeated passage in mycoplasma broth were investigated. Strain 80083 elicited a substantial serum antibody response after administration either in drinking water or by conjunctival sac instillation to 7-week-old SPF chickens. No vaccinated chickens developed air sac lesions when challenged by intra-abdominal (IA) injection with the virulent Ap3AS strain. Chickens vaccinated with strain 80083M (50 broth passages) showed only a weak serological response but were substantially protected when challenged 4 weeks after vaccination. Chickens vaccinated with 80083H (100 broth passages) were serologically negative 4 weeks after vaccination and developed severe air sac lesions after challenge. Thirty-seven-week-old hens vaccinated 6 months previously with strain 80083 had high serum antibody levels and were completely protected against IA challenge with the homologous strain. However, 4/6 showed mild air sac lesions when challenged intra-abdominally with strain Ap3AS. Another group showed high M. gallisepticum serum antibody levels 6 months after vaccination with strain Ap3AS but 4/6 and 2/6 showed mild lesions after IA challenge with strains Ap3AS or 80083, respectively. Strains 80083 or 80083M were administered by conjunctival sac instillation to susceptible 11-week-old commercial pullets at the time of fowl pox vaccination. The concurrent use of both vaccines had no apparent adverse effect on the health of the chickens. Similar protection against IA challenge with strain Ap3AS was produced with the M. gallisepticum vaccines whether used alone or in combination with fowl pox.     

鸡毒支原体研究概况

鸡毒支原体(MG)是对养禽业危害很大的支原体,主要导致禽类慢性呼吸道疾病(CRD),以禽的结膜炎、产蛋率及饲料转换率下降、屠宰率下降等为主要特征。MG可通过垂直和水平传播方式在鸡群中传播,每年给全球家禽产业带来巨大经济损失。随着对MG细胞表面抗原黏附素蛋白(pMGA)和PvpA、GapA的结构与功能研究的深入,K株、TG5株等MG疫苗研究也取得较大进展。由于抗生素的滥用,MG基因中也发生耐药突变,产生了QRDRs等抗药结构,导致MG在耐药性上也出现新的特点。论文主要对国内外MG的疫苗开发、耐药情况和检测技术等进行综述,旨在对家禽MG的综合防控提供借鉴。     

Virulence and transmissibility of Mycoplasma gallisepticum

The virulence of 4 low passage strains of Mycoplasma gallisepticum obtained from different sources within Australia was studied by experimental infection of chickens. Strain Ap3AS, originally isolated from the air sac of a broiler chicken, produced severe air sac lesions following injection into the abdominal air sacs of 2-week or 3-week-old chickens, and adult hens. Strain 80083 which was isolated from a clinically normal broiler breeder hen was also capable of producing gross air sac lesions following intra-abdominal (IA) injection, although it did so less consistently than strain Ap3AS. Strain 82078 isolated from a layer hen and strain QXO which was isolated from a turkey were also moderately pathogenic in terms of the incidence and severity of lesions elicited following IA injection. Strains Ap3AS and 80083 both caused a substantial loss of egg production over a 5 week period after IA infection of 27-week-old hens. Neither strain Ap3AS nor 80083 caused gross lesions or loss of egg production when administered alone into the upper respiratory tract. However, when inoculated into the conjunctival sac in combination with the Vic S strain of infectious bronchitis virus (IBV) strains Ap3AS and 80083 produced identical clinical signs of conjunctivitis. The mean numbers of M. gallisepticum in tracheal washings were significantly higher 2 weeks after infection in the group receiving strain 80083 in combination with IBV than in the group infected with strain Ap3AS and IBV (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

氟罗沙星对禽败血霉形体（Mycoplasma gallisepticum）病的药效研究

体外抑菌试验测得氟罗沙星（Ｆｌｅｒｏｘａｃｉｎ）对禽败血霉形体（Ｍｙｃｏｐｌａｓｍａｇａｌｉｓｅｐｔｉｃｕｍ）的最小抑菌浓度（ＭＩＣ）为０．０１５ｍｇ／Ｌ。体内药效试验表明,氟罗沙星以２５、５０、１００ｍｇ／Ｌ饮水给药和以５、１０、１５ｍｇ／ｋｇ肌注给药（１次／ｄ）,连续用药５ｄ,对人工气囊接种禽败血霉形体培养液（０．２ｍＬ,约含１０８ｃｆｕ）的雏鸡,保护率均为１００％（３０／３０）,而感染不给药组雏鸡存活率为９３．３％（２８／３０）;相对增重率分别为９０．８％、９１．５％、９２．３％和９１．５％、９１．８％、９２．９％,显著高于感染不给药组（７３．２％）;气囊损伤分分别为２．９３、２．６２、０．９３和１．８、１．１、１．０,而感染不给药组为６．５７,差异显著（Ｐ＜０．０５）;血清玻板凝集试验阳性率分别为２０％（２／１０）、１０％（１／１０）、０（０／１０）和３０％（３／１０）、１０％（１／１０）、１０％（１／１０）,均极显著低于感染不给药组１００％（１０／１０）（Ｐ＜０．０１）。氟罗沙星不同给药途径及不同剂量间药效差异不显著。