牛至油与5种抗生素联合用药的抗菌作用研究

该试验旨在测定牛至油及其与5种抗生素联合应用的抗菌活性。用两倍稀释法测定牛至油对16株临床分离大肠杆菌,包括8株产超广谱β-内酰胺酶（ESBLs）菌和8株不产ESBLs菌的最小抑菌浓度（MIC）值．挑选几株耐药菌株用棋盘法测定牛至油与头孢噻呋、左旋氧氟沙星、阿奇霉素、多西环素、氟苯尼考联用的抗菌活性。结果表明：牛至油对产ESBLs和不产ESBLs菌的MIC值均为0．25mg／ml;牛至油与左旋氧氟沙星和氟苯尼考之间存在协同作用．与头孢噻呋、阿奇霉素、多西环素存在相加作用或无关作用。     

牛至油及抗生素联用对产ESBLs大肠埃希氏菌体外抗菌作用

采用微量肉汤稀释法,测定了牛至油和5种抗菌药物头孢噻呋、左氧氟沙星、多西环素、阿奇霉素、氟苯尼考及它们之间联用对临床分离的8株产超广谱β-内酰胺酶(ESBLs)鸡大肠杆菌的MIC值,考察牛至油和抗菌药物之间的相互作用。结果表明,8株产ESBLs鸡大肠杆菌对牛至油敏感,对5种抗菌药均有耐药性,头孢噻呋与牛至油联用表现为无相关作用;多西环素、阿奇霉素与牛至油联用主要表现为相加作用;左氧氟沙星、氟苯尼考与牛至油联用主要表现为协同作用。     

牛至油和小檗碱联用对产ESBLs鸡大肠埃希菌的体外抗菌试验

测定了牛至油、小檗碱、头孢噻呋、左氧氟沙星、多西环素及氟苯尼考6种药物对分离产ESBLs鸡大肠杆菌的最小抑菌浓度(MIC)及牛至油与小檗碱等5种药物联用对12株产ESBLs鸡大肠杆菌和标准菌的部分抑菌浓度(FIC)指数,分析牛至油与小檗碱等5种药物间的相互作用,为筛选对产ESBLs鸡大肠杆菌有效的药物及复方牛至油口服乳的推广提供依据。结果表明,12株产ESBLs鸡大肠杆菌对牛至油、小檗碱敏感,对4种抗菌药均有不同程度的耐药性;小檗碱与牛至油联用均表现为协同作用。     

牛至油与5种抗生素联合用药的抗菌作用研究

该试验旨在测定牛至油及其与5种抗生素联合应用的抗菌活性.用两倍稀释法测定牛至油对16株临床分离大肠杆菌,包括8株产超广谱β-内酰胺酶(ESBLs)茵和8株不产ESBLs茵的最小抑菌浓度(MIC)值,挑选几株耐药菌株用棋盘法测定牛至油与头孢噻呋、左旋氧氟沙星、阿奇霉素、多西环素、氟苯尼考联用的抗茵活性.结果表明:牛至油对产ESBLs和不产ESBLs茵的MIC值均为0.25mg/ml;牛至油与左旋氧氟沙星和氟苯尼考之间存在协同作用,与头孢噻呋、阿奇霉素、多西环素存在相加作用或无关作用.     

异丙氧苯胍与黏菌素联用对多杀性巴氏杆菌的体内外抗菌作用

【目的】研究异丙氧苯胍与黏菌素联用对多杀性巴氏杆菌的体内外抗菌作用,为开发有效的新型黏菌素增效剂及临床防治多杀性巴氏杆菌病提供数据支持。【方法】通过微量肉汤稀释法测定异丙氧苯胍与黏菌素对多杀性巴氏杆菌的最小抑菌浓度,再通过棋盘法联合药敏试验和时间杀菌曲线评价异丙氧苯胍与黏菌素联用对多杀性巴氏杆菌的体外抗菌作用,并进一步通过建立小鼠肺部感染多杀性巴氏杆菌模型来评价两者联用的体内抗菌效果。【结果】药敏试验结果显示,异丙氧苯胍对多杀性巴氏杆菌无抗菌作用(MIC>256μg/mL),黏菌素对受试菌株的最小抑菌浓度范围为1～8μg/mL。联合药敏试验结果显示,异丙氧苯胍与黏菌素联用时能增强黏菌素的抗菌活性(分级抑菌浓度指数在0.094～0.313),表现出良好的协同抗菌作用。体外时间杀菌曲线结果进一步表明,联合用药组可显著降低细菌数量,当亚抑菌浓度(0.5μg/mL)的黏菌素与异丙氧苯胍联用时即可达到杀菌效果。在小鼠肺部感染模型中,与黏菌素或异丙氧苯胍单药组相比,异丙氧苯胍与黏菌素联合组能显著或极显著降低小鼠肺部多杀性巴氏杆菌的载菌量(P<0.05或P<0.01)。HE染色观察...     

硫酸黏菌素对培养分离的土壤优势细菌的影响

随着抗生素在畜禽养殖业上的广泛应用,药物残留对生态环境的潜在隐患日益突出.为了了解硫酸黏菌素在环境中残留对土壤细菌数量和耐药性的影响,本实验对硫酸黏菌素作用35 d后用纯培养法分离的土壤细菌进行了计数,并对作用70 d后的土壤优势细菌进行了抗菌药物敏感性试验.结果表明,实验组的土壤细菌总数均低于对照组,且培养分离的细菌数量与药物浓度成反比;在供试的13种抗菌药中,硫酸黏菌素敏感菌对其中的11种药物的敏感性与硫酸黏菌素耐药菌差异显著（P＜0.05）.     

阿莫西林和硫酸黏菌素对奶牛乳房炎病原菌的体外抑菌试验

为研究阿莫西林与硫酸黏菌素对奶牛乳房炎病原菌的体外抗菌活性,本试验选择139株奶牛乳房炎临床分离菌株,采用微量肉汤稀释法,测定了阿莫西林、硫酸黏菌素单用及其联合用药对以上3种主要致病菌的最小抑菌浓度(MIC)。结果:阿莫西林对大肠杆菌、金黄色葡萄球菌和链球菌的MIC范围分别为:2.0~512.0μg/m L、0.125~128.0μg/m L和0.125~1.0μg/m L;硫酸黏菌素对大肠杆菌、金黄色葡萄球菌和链球菌的MIC范围分别为0.5~8.0μg/m L、32.0~128.0μg/m L和64.0~1 024.0μg/m L。二者联用后,对20株奶牛乳房炎大肠杆菌、金黄色葡萄球菌和链球菌FIC平均值分别为0.91、0.85、1.25,对所有菌株的FIC平均值为0.93。结果表明,阿莫西林对链球菌高度敏感;对大肠杆菌及金黄色葡萄球菌适度敏感;硫酸黏菌素对引起奶牛乳房炎的大肠杆菌表现出较高的敏感性,对金黄色葡萄球菌、链球菌的敏感性较低。阿莫西林与硫酸黏菌素联用后,对3种受试菌主要呈现相加作用。     

猪体内黏菌素残留检测方法与消除规律

黏菌素抗菌谱广,抗菌作用强,不易产生耐药性,被许多国家和地区批准作为饲料添加剂或兽药在猪、禽、牛和羊等动物上使用。国外黏菌素的残留检测方法主要有微生物法、HPLC、ELISA、薄层色谱法等。HPLC当前的检测限和变异系数均较低,但设备昂贵,且需衍生化,成本高[1];ELISA可作黏菌素的筛选方法[2],但其假阳性较多;薄层色谱法灵敏度不高,主要用于快速检测或对灵敏度要求不高的检测[3]。美国和英国药典规定黏菌素的含量测定使用微生物法,以博代特氏菌作为检测菌,而国内常用《中国药典》规定的以大肠杆菌为检测菌的微生物法[4]。目前我国…     

地锦草与10种抗菌药联用对鸡大肠杆菌的体外抑菌效果

为了观察地锦草与阿莫西林等抗菌药物联用对鸡致病性大肠杆菌的体外抑菌效果,试验采用琼脂稀释法分别测定地锦草与10种抗菌药物联用的抑菌作用,并与地锦草和抗菌药物单独应用时的抑菌效果相比较。结果表明:12株大肠杆菌对抗菌药物呈现多重耐药性,地锦草对大肠杆菌的最小抑菌浓度范围为7.812 5~31.250 mg/mL;地锦草与头孢曲松、头孢噻呋、氟苯尼考、多西环素联用时的抑菌协同率为58.3%~83.3%,与阿米卡星、大观霉素、恩诺沙星、黏菌素联用时的抑菌颉颃率为58.3%~100%,与阿莫西林、安普霉素联用时显示无关或颉颃作用。说明地锦草可以增强头孢曲松、头孢噻呋、氟苯尼考、多西环素对大肠杆菌的抑菌作用,可以颉颃阿米卡星、大观霉素、恩诺沙星、黏菌素对大肠杆菌的抑菌作用。     

两种益生芽孢杆菌体外抑菌活性及其耐药性研究

试验分别采用牛津杯法和微量肉汤稀释法进行益生芽孢杆菌体外抑菌活性及耐药性研究,结果显示,枯草芽孢杆菌和地衣芽孢杆菌对大肠埃希菌C83901、C83917和沙门菌有中、低度抑制作用;对抗敌素、硫酸黏菌素、喹乙醇有一定耐药性．而吉他霉素和硫酸新霉素对这2种杆菌抑制作用较强,不宜联用。     

赤芍水提物与抗菌药联合对耐药大肠杆菌抑菌作用的研究

为了探究赤芍水提物与抗菌药联合对耐药大肠杆菌的体外抑菌作用,采用微量肉汤稀释法与微量棋盘法来测定各抗菌药与赤芍水提物的最低抑菌浓度(MIC)及二者联合作用后的分级抑菌浓度指数(FICI)。结果显示赤芍水提物与头孢曲松钠、阿莫西林、环丙沙星、诺氟沙星、左旋氧氟沙星、磷霉素、痢菌净、克林沙星、磺胺间甲氧嘧啶、加替沙星、阿米卡星、头孢他啶、林可霉素、头孢噻呋钠、氟苯尼考、阿奇霉素、头孢噻肟、利福平联合作用后的FICI分别为0.27、2.50、1.02、1.01、3.00、0.28、1.02、1.02、1.02、2.02、1.02、0.75、0.56、0.75、0.50、3.00、0.75、0.38。结果表明赤芍水提物与头孢曲松钠、磷霉素、氟苯尼考、利福平联合作用时有协同作用;与林可霉素、头孢噻呋钠、头孢噻肟、头孢他啶联合作用时有相加作用;与阿莫西林、左旋氧氟沙星、加替沙星、阿奇霉素联合作用时有颉颃作用;与环丙沙星、诺氟沙星、痢菌净、克林沙星、磺胺间甲氧嘧啶、阿米卡星联合作用时表现为无关作用。     

Antimicrobial susceptibility of Actinobacillus pleuropneumoniae, Escherichia coli, and Salmonella choleraesuis recovered from Taiwanese swine.

Minimum inhibition concentrations (MICs) were determined for ampicillin, ceftiofur, cephalothin, chloramphenicol, enrofloxacin, gentamicin, lincomycin, lincospectin (lincomycin/spectinomycin), neomycin, premafloxacin, spectinomycin, sulfamethoxazole/trimethoprim, and tetracycline against a total of 180 isolates of Actinobacillus pleuropneumoniae, Escherichia coli, and Salmonella choleraesuis (60 each) clinically isolated from pigs on farms in Taiwan from 1994 to 1996. No more than 3 isolates per farm were used. Ceftiofur had the highest activity in vitro against isolates of A. pleuropneumoniae, E. coli, and S. choleraesuis, with MIC90 values of 0.03, 2, and 1 microg/ml, respectively. Premafloxacin was highly active against isolates of A. pleuropneumoniae, E. coli, and S. choleraesuis, with MIC90 values of 2, 8, and 0.5 microg/ml, respectively, which were lower than those with enrofloxacin (MIC90 8, 32, and 2 microg/ml, respectively). Neomycin was moderately active against A. pleuropneumoniae and E. coli, with MIC90 values of 8 and 64 microg/ml, respectively, but was inactive with S. choleraesuis. Gentamicin showed high activity against A. pleuropneumoniae (MIC90 of 2 microg/ml) but was only moderately active with E. coli and S. choleraesuis (MIC90 of 64 and 32 microg/ml). Cephalothin was highly active against isolates of A. pleuropneumoniae (MIC90 of 1 microg/ml) but was inactive with E. coli (MIC90 of 128 microg/ml). Lincomycin had moderate activity (MIC90 of 32 microg/ml) against A. pleuropneumoniae. Chloramphenicol, lincomycin, and tetracycline were inactive with E. coli and S. choleraesuis (MIC90 > 128 microg/ml). In conclusion, ceftiofur and premafloxacin were highly active against isolates of A. pleuropneumoniae, E. coli, and S. choleraesuis, enrofloxacin and gentamicin were highly to moderately active; cephalothin was highly active against A. pleuropneumoniae and moderately active against S. cholearesuis; chloramphenicol, lincomycin, and tetracycline were active only with A. pleuropneumoniae; neomycin was moderately active against A. pleuropneumoniae and E. coli. The other antimicrobials tested were inactive.     

母猪子宫内膜炎致病菌药敏试验及临床治疗

母猪子宫内膜炎致病分离菌药敏试验结果显示,头孢噻呋、林可霉素对大肠埃希菌、链球菌和葡萄球菌均为高度敏感;红霉素、链霉素、土霉素对以上3种细菌均为低敏感。根据药敏试验结果,将南平市某种猪场90头子宫内膜炎病猪进行分组治疗试验。将90头母猪随机分成3组,每组30头母猪,治疗组A,用药敏试验敏感药物头孢噻呋进行治疗;治疗组B,用药敏试验敏感药物林可霉素进行治疗;治疗组C,用青霉素、链霉素治疗做为治疗对照组;另外选择30头健康母猪做为健康对照组。治疗试验显示,母猪子宫内膜炎用敏感药物治疗有效,且治愈后的母猪受胎率、产仔数不受影响。     

Prevalence of Salmonella, Campylobacter, and Escherichia coli on ostrich carcasses and the susceptibility of ostrich-origin E. coli isolates to various antibiotics

There has been limited research on the prevalence of foodborne pathogens such as Escherichia coli O157:H7, Salmonella, and Campylobacter on ostrich carcasses. Likewise, few studies have been done in ostriches to determine the antimicrobial susceptibilities of common bacteria, like E. coli. In this study, ostrich carcasses were sampled from eight slaughterhouses in Ohio and one in Indiana. Although results demonstrated no E. coli O157:H7 from the carcasses sampled, 91% (116/128) of the dressed carcasses sampled had E. coli present. One carcass sample (1/152) was positive for Salmonella. Campylobacter were detected in 10% (19/191) of the carcasses. Antimicrobial susceptibility testing on 93 carcass E. coli isolates showed resistance to erythromycin (99%), neomycin (65%), netilmicin (2%), oxytetracycline (22%), streptomycin (2%), and trimethoprim (3%). All isolates were resistant to bacitracin, lincomycin, penicillin, and vancomycin. For the large intestinal sampling, 149 of the 217 (69%) samples had E. coli present. Fifty of these 149 samples had E. coli levels ranging from 10(2) to 10(5) colony-forming units/g feces. Campylobacter were isolated from 6 of 201 (3%) samples. No Salmonella colony was detected. Antimicrobial susceptibility testing on 131 intestinal E. coli isolates showed resistance to erythromycin (98%), neomycin (66%), netilmicin (34%), oxytetracycline (34%), streptomycin (40%), and trimethoprim (13%). All isolates were resistant to bacitracin, lincomycin, penicillin, and vancomycin.     

Susceptibility of bacterial pathogens against lincomycin/spectinomycin (1/2), penicillin G/neomycin (1/1), and penicillin G/dihydrostreptomycin (1/1) as determined in the BfT-GermVet monitoring program 2004-2006

A total of 368 bacterial pathogens, including 72 coagulase-positive and coagulase-variable staphylococci, 97 beta-haemolytic streptococci, 51 Escherichia coli, 75 Pasteurella multocida, 25 Mannheimia haemolytica, 25 Pseudomonas aeruginosa, and 23 Arcanobacterium pyogenes, were investigated for their susceptibility to the three combinations of antimicrobial agents lincomycin/spectinomycin (1/2), penicillin G/neomycin (1/1), and penicillin G/dihydrostreptomycin (1/1) in comparison to their susceptibility to the corresponding single substances. When comparing the minimum inhibitory concentrations (MICs) determined for any of the three combinations with those for the single substances, the lowest MIC of one of the two substances usually determined the MIC of the combination.This observation was made for all three combinations and all bacterial pathogens tested.Thus, it is assumed that the combination of lincomycin with spectinomycin as well as that of penicillin with either neomycin or dihydrostreptomycin resulted in an extended spectrum of target bacterial pathogens rather than in an increase in antimicrobial efficacy.     

兔源大肠杆菌耐药表型分析

从9个规模化兔场分离到50株大肠杆菌,选取了16种抗生素对这50株大肠杆菌运用Kirby-Barer法进行药敏试验,结果表明：先锋霉素、新霉素、痢特灵、丁胺卡那霉素的抑菌作用比较强;而细菌对氨苄青霉素、阿莫西林、强力霉素、林可霉素则表现出极其高的耐药性,对四环素、氯霉素、卡那霉素、庆大霉素、复方新诺明、恩诺沙星、诺氟沙星、链霉素也有很高的耐药性。所分离的大肠杆菌以耐药8～12种居多,占细菌总数的78％,未发现不耐药的菌株与全部耐药的菌株。     

抗菌药物联合使用对耐达氟沙星鸡毒支原体的体外抑制作用研究

为探究抗菌药物联合使用对耐达氟沙星鸡毒支原体的体外抑制效果,选择鸡毒支原体标准株S6和对达氟沙星MIC升高程度不同的突变株M1、M2和M4,分别测定泰乐菌素、大观霉素、林可霉素、泰妙菌素、替米考星和多西环素种对4株鸡毒支原体的最低抑菌浓度,并使用达氟沙星分别联合上述6种抗菌药物进行体外抑菌试验。结果显示:除达氟沙星外,其余抗生素对S6、M1、M2和M4的最低抑菌浓度均相同,且泰妙菌素的敏感性最高(0.0016μg/mL),林可霉素敏感性最低(4μg/mL);联合抑菌试验结果显示,达氟沙星与大观霉素联合对S6、M1、M2和M4均为相加作用;达氟沙星联合林可霉素对S6和M2表现为相加作用,对M1与M4均表现为无关作用,达氟沙星与泰乐菌素、泰妙菌素、替米考星和多西环素联合均为无关作用。研究结果显示达氟沙星联合大观霉素的作用效果最好。     

Lincomycin-induced severe colitis in ponies: association with Clostridium cadaveris.

Four groups of two ponies, free of fecal Salmonella and Clostridium cadaveris, were treated as follows: Group A, control group; B, single nasogastrically administered dose of lincomycin (25 mg/kg) followed 48 h later by 3 L of C. cadaveris (10(9) organisms/mL); C, the same dose of lincomycin as group B; D, the same dose of C. cadaveris as group B on each of three occasions at 12 h intervals. Groups A and D remained healthy, but groups B and C developed severe colitis 48-56 h (B) or 72 h (C) after administration of lincomycin. Three ponies were euthanized and one in group B died. Clostridium cadaveris was isolated at about 10(6)/mL of colonic contents from these ponies, but one pony in group B also yielded Salmonella typhimurium from the colon. Subsequent challenge of group A ponies (3 L of C. cadaveris 10(9)/mL, three times at 12 h intervals) did not produce colitis. Nasogastric administration of lincomycin (25 mg/kg) to group A and D ponies, 20 days after administration of C. cadaveris, resulted in severe colitis in all ponies within 48-72 h. Salmonella agona was isolated from the colonic contents of one pony and C. cadaveris (10(6)/mL) from all four ponies. Clostridium cadaveris was not isolated from the colonic content of 45 healthy horses examined immediately after death. These studies confirm the potential for lincomycin to induce severe enterocolitis in ponies and implicate C. cadaveris further as a cause of "idiopathic colitis" in ponies.     

The Effect of Adsorbant and Anti-inflammatory Drugs on Secretion in Ligated Segments of Pig Intestine Infected with Escherichia coli

Four adsorbant drug preparations, Kaopectate, colloidal Attapulgite, noncolloidal Attapulgite and Pepto-bismol were investigated for their effects on fluid accumulation in ligated segments of pig intestine inoculated with enteropathogenic Escherichia coli. Two anti-inflammatory drugs. aspirin and methylprednisolone, and two antibiotics, lincomycin and polymyxin B, were also tested. All the drugs except the two anti-inflammatory products were given by injection into the lumen of the intestine. Aspirin was given orally and methylprednisolone was given intramuscularly. The antibiotics were tested at levels at which they had no significant antibacterial effect in in vitro tests. The adsorbant drugs colloidal Attapulgite and Pepto-bismol were shown to be effective in reducing fluid accumulation in ligated segments of pig intestine infected with enteropathogenic E. coli. In the case of Peptobismol this effect was associated with an antibacterial effect as well as an antitoxic effect, probably due to its adsorbant properties. It is possible that an aspirin-like effect in the gut due to the active ingredient bismuth subsalicylate may have contributed to the effectiveness of Pepto-bismol. Colloidal Attapulgite was demonstrated to have an antitoxic effect but did not have an antibacterial effect.

In high doses, the anti-inflammatory drugs acetylsalicylic acid and methylprednisolone were marginally effective in reduction of fluid accumulation in the same test system. Lincomycin was shown to reduce intestinal fluid secretion, whereas polymyxin B had no effect.

     

Influence of an organic acid blend and essential oil blend,individually or in combination,on growth performance,carcass parameters,apparent digestibility,intestinal microflora and intestinal morphology of broilers

1. This study aimed to evaluate the influence of an organic acid (OA) and essential oil (EO) blends, individually or in combination, on growth performance, carcass parameters, apparent digestibility, intestinal microflora and intestinal morphology of broilers.

2. A total of 480 one-d-old male Ross 308 chicks were randomly assigned to 4 treatments consisting of 4 replicates each (n = 30 birds in each replicate). Dietary treatments consisted of a basal diet (control), and basal diet supplemented with 2 g/kg OA blend (OAB), 300 mg/kg EO blend (EOB), or with 2 g/kg OA and 300 mg/kg EO blend (OAB–EOB) for 42 d.

3. The dietary supplementation with EO blend or in combination with OA blend increased body weight gain and improved feed efficiency as compared to control. Dietary treatments had no significant effects on feed consumption or relative organ weights of broilers.

4. The OAB diet increased carcass yield compared to the control diet but the lowest carcass yield occurred with the OAB–EOB combination. Birds fed on EOB and OAB–EOB diets had lower ileum Escherichia coli counts than birds fed on the control diet.

5. There was no significant effect of treatments on apparent digestibility at 16–21 d but the EOB and OAB–EOB diets increased apparent digestibility of dry matter and crude protein during the finisher period (d 37–42) compared to the control diet.

6. Birds fed on the EOB and OAB–EOB diets had greater villus height in the ileum at 21 and 42 d of age and had lower crypt depth in the ileum at 42 d of age than birds given the control diet.

7. In conclusion, beneficial effects of the use of EO blend individually or in combination with the OA blend were observed but the OA blend alone was ineffective. Furthermore, the use of the combination of OA and EO was more effective, in some respects, than their individual use.