福建白羽肉鸡鸡毒支原体的分离鉴定及最小抑菌浓度测定

为了解福建白羽肉鸡中鸡毒支原体（MG）对临床常用药物的敏感性,本研究从2个商品代白羽肉鸡养殖场采集了疑似患慢性呼吸道病（CRD）的鸡喉拭子40份,接种于适宜的支原体培养基上进行纯化。通过对菌株生物学特性分析、细菌形态学观察、PCR测序及动物回归试验进行鉴定,并利用最低抑菌浓度（MIC）测定了分离株对临床常用抗菌药的敏感性。结果显示,本试验成功获得2株MG,命名为MX和HY。将分离株接种于含有酚红的支原体液体培养基中能分解葡萄糖产酸使培养基颜色由红变黄;固体培养基于低倍镜下观察到典型的"荷包蛋"状菌落;分离株经过Dienes染色后的菌落中心呈致密深蓝色,边缘淡蓝,且30 min后不褪色,并具有较强吸附红细胞的能力,呈现典型MG培养特征;动物回归试验和分离株pvpA基因测序结果显示,2株MG分离株均具有较强致病性,证实其与R株的亲缘关系最近;药敏试验结果显示,MX和HY对泰妙菌素、氟苯尼考和泰乐霉素表现出了高度敏感性,其次是盐酸恩诺沙星、盐酸大观霉素,而对具有与泰乐霉素类似分子结构和抗菌谱的畜禽专用抗生素替米考星敏感性较差,此差异可能与临床上长期应用该药有关。研究结果表明,福建地区商品代白羽肉鸡中存在致病性MG流行,泰妙菌素可以作为临床防治MG的首选药物。     

鸡毒支原体的分离与鉴定

从广东、四川及北京地区患有慢性呼吸道疾病的不同鸡场采集194份样本,接种FM-4培养基进行分离培养。对符合鸡毒支原体培养特性培养物采用PCR加以鉴定,结果培养鉴定出69株鸡毒支原体,其分离率为35.57%(69株/194株)。     

鸡毒支原体的分离培养和初步鉴定

从济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、生化试验、血清学鉴定，证明该分离株为鸡毒支原体（MG）。     

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)。     

混合感染中鸡毒支原体和副鸡嗜血杆菌的分离鉴定

从冀南地区某养鸡场患呼吸道疾病的病鸡群采集5份样品（气管和眶下窦分泌物）中，同时分离到鸡毒支原体和副鸡嗜血杆菌两种病原体。通过病原的分离培养、细菌L型检验、生化试验、血清学试验等鉴定，证明分离的鸡毒支原体与国际标准株S6的血清型一致，副鸡嗜血杆菌的血清型为A型，动物试验表明，分离的鸡毒支原体和副鸡嗜血杆菌均具有明显的致病性，说明该病鸡群同时混合感染了鸡毒支原体和副鸡嗜血杆菌。     

1株鸡毒支原体的分离鉴定及体外敏感中药的筛选

本研究旨在对山东泰安地区鸡毒支原体的流行菌株进行分离培养及鉴定和纯化,并针对该分离株筛选体外敏感的中药,为后续进一步研究提供材料。采用液体培养法与固体培养法从病鸡组织样品中分离、培养和纯化鸡毒支原体,并通过瑞士染色和姬姆萨染色、血清学方法及分子生物学方法对分离株进行初步鉴定,在此基础上,采用微量稀释法测定8种中药对分离菌株的最小抑菌浓度（MIC）,从而筛选到对分离菌株敏感的中药。结果显示,分离菌株在鸡毒支原体液体培养基中增殖后,培养基颜色由红变黄且呈半透明状态,在固体培养基中培养后呈典型的"煎蛋"样儿菌落,均符合鸡毒支原体培养特性;瑞士染色和姬姆萨染色结果显示,菌体形态符合鸡毒支原体的特征;血清学鉴定结果显示,分离株与鸡毒支原体阳性血清发生凝集;分子生物学鉴定结果显示,所扩增的核酸序列与鸡毒支原体匹配度高达99%;MIC测定结果显示,中药黄连和黄柏对分离的鸡毒支原体的抑菌活性较强,属敏感范畴,其MIC分别为≤0.98和0.39 mg/mL,而中药金荞麦和鱼腥草对鸡毒支原体中度敏感,MIC均≥125 mg/mL,板蓝根、白鲜皮、当归、艾叶对鸡毒支原体均不敏感。综上所述,本研究成功分离到1株鸡毒支原体,并且筛选出4种对该菌株敏感的中药,分别为黄连、黄柏、金荞麦和鱼腥草,为后期进一步研究防治鸡毒支原体病的中药组方时提供参考依据。     

鸡毒支原体的分离鉴定

鸡毒支原体（Mycoplasma gallisepticum,MG）会引发鸡的慢性呼吸道疾病（chronic respiratory disease,CRD）。本研究从吉林经济技术开发区鸡场采集的疑似支原体感染病料中分离、培养获得一菌株,经菌落形态观察、菌落红细胞吸附试验、生化特性测定及血清学鉴定等试验,证明该分离株为鸡毒支原体（MG）,并命名为JL株。     

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…     

鸡毒支原体的分离培养和初步鉴定

从济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、生化试验、血清学鉴定,证明该分离株为鸡毒支原体(MG)。     

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     

In vitro sensitivity of New Zealand strains of Mycoplasma ovipneumoniae to some antibiotics

Extract

Over the last year or so, there have been two major veterinary matters which have undoubtedly shaped this Association's current policy, and, because of their importance, I believe they may well continue to do so for many years.     

沙门氏菌对六种氟喹诺酮类药物的敏感性试验

对鸡源、猪源、人源、食品源的沙门氏菌进行了鉴定,对敏感菌株进行了耐药性诱导;并用琼脂平板二倍稀释法,测定了6种氟喹诺酮类药物对临床分离和体外诱导的68株沙门氏菌的MIC,结果表明临床沙门氏菌对环丙沙星的耐药率达61.8%(37/60),而且6种氟喹诺酮类药物之间的交叉耐药现象非常严重.     

Isolation and immunological detection of Mycoplasma ovipneumoniae in sheep with atypical pneumonia, and lack of a role for Mycoplasma arginini

Mycoplasma ovipneumoniae NCTC 10151(T) and four new isolates from UK sheep flocks were compared. Only glucose and pyruvate were used as energy sources by the five strains: glucose was the best energy source for the type strain, pyruvate supported better growth of the new strains. Whole cell protein patterns and antigenic profiles showed high similarity between all five strains. The new isolates fell into two groups in ELISA tests. Serum samples from 30 pneumonic sheep were assessed for M. ovipneumoniae infection and Mycoplasma arginini co-infection. Fourteen (out of 30) serum samples were positive for M. ovipneumoniae both by ELISA and immunoblotting. Twelve antigenic proteins of M. ovipneumoniae were detected in infected serum samples: the antigen patterns were unique, with between one and at least seven occurring in any one sample. All serum samples were designated as negative for M. arginini antibodies by both ELISA and immunoblotting.     

Evaluation of efflux pump inhibitory activity of some plant extracts and using them as adjuvants to potentiate the inhibitory activity of some antibiotics against Staphylococcus aureus

Background:Antibiotic-resistant pathogens became a real global threat to human and animal health. This needs to concentrate the efforts to minimize and control these organisms. Efflux pumps are considered one of the important strategies used by bacteria to exclude harmful materials from the cell. Inhibition of these pumps can be an active strategy against multidrug resistance pathogens. There are two sources of efflux pump inhibitors that can be used, chemical and natural inhibitors. The chemical origin efflux pump inhibitors have many toxic side effects while the natural origin is characterized by a wide margin of safety for the host cell.Aim:In this study, the ability of some plant extracts like (propolis show rosemary, clove, capsaicin, and cumin) to potentiate the inhibitory activity of some antibiotics such as (ciprofloxacin, erythromycin, gentamycin, tetracycline, and ampicillin) against Staphylococcus aureus pathogen were tested.Methods:Efflux pump inhibitory activity of the selected plant extracts was tested using an ethidium bromide (EtBr) accumulation assay.Results:The results have shown that Propolis has a significant synergistic effect in combination with ciprofloxacin, erythromycin, and gentamycin. While it has no effect with tetracycline or ampicillin. Also, no synergic effect was noticed in a combination of the minimum inhibitory concentration for the selected plant extracts (rosemary, clove, capsaicin, and cumin) with any of the tested antibiotics. Interestingly, according to the results of the EtBr accumulation assay, Propolis has potent inhibitory activity against the S. aureus (MRS usa300) pump system.Conclusion:This study suggests that Propolis might act as a resistance breaker that is able to restore the activity of ciprofloxacin, erythromycin, and gentamycin against S. aureus strains, in case of the efflux-mediated antimicrobial resistance mechanisms.     

Comparing the minimum inhibitory and mutant prevention concentrations of selected antibiotics against animal isolates of Pasteurella multocida and Salmonella typhimurium

Historically, the use of antibiotics was not well regulated in veterinary medicine. The emergence of antibiotic resistance (ABR) in pathogenic bacteria in human and veterinary medicine has driven the need for greater antibiotic stewardship. The preservation of certain antibiotic classes for use exclusively in humans, especially in cases of multidrug resistance, has highlighted the need for veterinarians to reduce its use and redefine dosage regimens of antibiotics to ensure efficacy and guard against the development of ABR pathogens. The minimum inhibitory concentration (MIC), the lowest concentration of an antibiotic drug that will prevent the growth of a bacterium, is recognised as a method to assist in antibiotic dosage determination. Minimum inhibitory concentrations sometimes fail to deal with first-step mutants in bacterial populations; therefore dosing regimens based solely on MIC can lead to the development of ABR. The mutant prevention concentration (MPC) is the minimum inhibitory antibiotic concentration of the most resistant first-step mutant. Mutant prevention concentration determination as a complementary and sometimes preferable alternative to MIC determination for veterinarians when managing bacterial pathogens. The results of this study focused on livestock pathogens and antibiotics used to treat them, which had a MIC value of 0.25 µg/mL for enrofloxacin against all 27 isolates of Salmonella typhimurium. The MPC values were 0.50 µg/mL, with the exception of five isolates that had MPC values of 4.00 µg/mL. The MPC test yielded 65.52% (18 isolates) Salmonella isolates with florfenicol MICs in the sensitive range, while 11 isolates were in the resistant range. Seventeen isolates (58.62%) of Pasteurella multocida had MIC values in the susceptible range and 41.38% (12 isolates) had an intermediate MIC value. Mutant prevention concentration determinations as done in this study is effective for the antibiotic treatment of bacterial infections and minimising the development of resistance. The MPC method can be used to better control to prevent the development of antibiotic drug resistance used in animals.