中药水提物对体外猪链球菌生物被膜作用的试验

猪链球菌耐药性与生物被膜的形成有关,本试验选取常用的20味清热解毒的中药,采用微量稀释法测定20味中药水提物的最小抑菌浓度(MIC)和最小杀菌浓度(MBC),采用卡尔加里生物被膜装置和平板稀释法测定20味中药在亚MIC(1/2 MIC)药物浓度下对生物被膜的干预作用,结果表明:丁香叶、金银花、黄芩、穿心莲、黄柏和鱼腥草等中药水提物干预生物被膜效果显著(P0.05)大黄、黄连水提物干预生物被膜效果极显著(P0.01),通过细菌计数发现,0~72h,1/2MIC中药提取物对猪链球菌数量影,响不显著(P0.05)。丁香叶、大黄和黄连水提物对生物被膜中的猪链球菌具有很好的杀灭作用(P0.05)。     

大环内酯类药物对木糖葡萄球菌敏感菌株及其耐药菌株生物被膜形成的影响

为了探究大环内酯类药物泰乐菌素和阿奇霉素对木糖葡萄球菌敏感菌株及其耐药菌株生物被膜形成的影响,试验首先通过倍比稀释法测定两种药物对木糖葡萄球菌敏感菌株及其耐药菌株的最小抑菌浓度(MIC),然后利用结晶紫染色法考察木糖葡萄球菌敏感菌株及其耐药菌株生物被膜的形成能力,并测定细菌生长情况,最后考察两种药物浓度及药物孵育时间对生物被膜形成的影响。结果表明：木糖葡萄球菌耐药菌株生物被膜的形成能力弱于敏感菌株,木糖葡萄球菌敏感菌株与其耐药菌株的生长存在差异。0.312 5μg/mL的泰乐菌素和阿奇霉素对木糖葡萄球菌敏感菌株生物被膜的形成具有极显著抑制作用(P<0.01),对耐药菌株生物被膜形成的抑制作用不显著(P>0.05);25μg/mL的泰乐菌素和阿奇霉素对耐药菌株生物被膜的形成具有显著或极显著抑制作用(P<0.05或P<0.01)。随着药物孵育时间的延长,对生物被膜形成的抑制效果逐渐增强。说明大环内酯类药物泰乐菌素和阿奇霉素在一定程度上能抑制木糖葡萄球菌敏感菌株及其耐药菌株生物被膜的形成且具有时间依赖性。     

阿司匹林对木糖葡萄球菌体外生物被膜的作用

通过阿司匹林对木糖葡萄球菌生物被膜干预作用的研究,为木糖葡萄球菌生物被膜的治疗提供理论参考。通过结晶紫染色法(CV)、XTT分析法和激光共聚焦显微镜方法研究阿司匹林对木糖葡萄球菌生物被膜的作用及生物被膜下活菌和死菌的分布情况。结果显示,阿司匹林对木糖葡萄球菌有抑菌作用并且对其生物被膜的干预作用显著。     

鱼腥草对金黄色葡萄球菌生物被膜干预作用研究

研究鱼腥草水提物对金黄色葡萄球菌生物被膜的干预作用。采用微量肉汤稀释法测定鱼腥草水提物对金黄色葡萄球菌CMCC(B)26003的最低抑菌浓度;采用结晶紫染色法、扫描电镜及激光共聚焦显微镜评估鱼腥草水提物对CMCC(B)26003生物被膜形成的影响;最后采用实时荧光定量PCR方法测定鱼腥草水提物对O-乙酰丝氨酸硫化氢裂解酶B(O-acetylserine sulfhydrylase-B)cysM基因转录的影响。结果显示,鱼腥草水提物在12.500 mg/mL、6.250 mg/mL、3.125 mg/mL质量浓度下均可以有效抑制金黄色葡萄球菌生物被膜的形成,在12.500 mg/mL质量浓度下可下调cysM基因的表达。鱼腥草可能通过下调cysM基因的表达而抑制金黄色葡萄球菌生物被膜的形成。     

中草药对猪链球菌生物被膜形成的影响

采用结晶紫染色半定量法对实验室分离的15株猪链球菌进行生物被膜形成能力的测定,结果表明:分离的15株菌中有1株生物被膜形成能力中等,8株菌生物被膜形成能力较弱,6株菌没有形成生物被膜;采用试管两倍稀释法检测中草药(金银花、马齿苋、罗布麻)水提取物对形成生物被膜能力不同猪链球菌进行最小抑菌浓度和最小杀菌浓度测定,在低于最小抑菌浓度和最小杀菌浓度下对生物被膜形成能力中等的1株链球菌进行中草药对生物被膜形成能力影响的研究。试验结果显示:形成生物被膜能力越强,测得最小抑菌浓度和最小杀菌浓度值就越大,不同药物浓度对猪链球菌生物被膜形成的影响不同。该研究为猪链球菌病防治提供一定的指导。     

新疆南疆地区表皮葡萄球菌对氟苯尼考注射液的药物敏感性研究

为了探索新疆南疆地区表皮葡萄球菌对氟苯尼考注射液的敏感性，试验采用微量肉汤稀释法测定了氟苯尼考注射液对表皮葡萄球菌ATCC 35984和临床分离株的最低抑菌浓度(MIC)、最低杀菌浓度(MBC),对表皮葡萄球菌生长、生物被膜形成的抑制作用及表面疏水性的影响，测定了氟苯尼考注射液的体外抑菌效果及其对表皮葡萄球菌细胞膜完整性的影响。结果表明：氟苯尼考注射液对表皮葡萄球菌ATCC 35984和临床分离株的MIC值分别为4,2μg/mL,MBC值分别为16,8μg/mL。与未加氟苯尼考注射液的菌液相比，0.5μg/mL氟苯尼考注射液可显著抑制表皮葡萄球菌生长，0.25μg/mL氟苯尼考可显著抑制其生物被膜的形成(P<0.05),浓度>2μg/mL时抑制效果极显著(P<0.01),呈浓度依赖性；氟苯尼考注射液可降低表皮葡萄球菌细胞表面疏水性，呈浓度依赖性。当氟苯尼考注射液浓度为1/2 MIC时，可在体外显著抑制表皮葡萄球菌ATCC 35984生长(P<0.05);当浓度高于1 MIC时，可极显著抑制表皮葡萄球菌ATCC 35984和临床分离株生长(P<0.01)。当...     

猪链球菌2型生物被膜的生物学特性研究

通过细胞培养板法研究了猪链球菌2型生物被膜的生物学特性。结果显示:大部分猪链球菌均具有不同程度形成生物被膜的能力,其中3株(3/15)形成能力较强;猪链球菌生物被膜的成熟约需60 h,培养基中葡萄糖浓度是影响生物被膜形成的重要因素;生物被膜中的多糖含量显著高于浮游菌;氨苄青霉素钠和阿莫西林对这3株猪链球菌生物被膜的最低抑菌浓度(MIC)和最低杀菌浓度(MBC)均高于游离菌约2 500倍;扫描电镜观察发现,生物被膜内猪链球菌彼此黏连,形成致密的三维立体结构。对猪链球菌生物被膜生物学特性的研究为进一步揭示生物被膜的形成机制、耐药机理,以及清除生物被膜等提供理论依据。     

喹诺酮类药物对嗜水气单胞菌体外生物被膜形成能力的影响

采用微量肉汤稀释法测定3种喹诺酮类药物对21株嗜水气单胞菌的最小抑菌浓度(MIC),体外建立其生物被膜(BF),采用结晶紫法和扫描电镜的方法研究生物被膜的形成和结构,并观察喹诺酮类药物对生物被膜形成能力的影响。结果表明:喹诺酮类药物对嗜水气单胞菌有较强的抑制作用,诺氟沙星、环丙沙星、恩诺沙星的抑菌率分别为90.5%,95.25%和85.7%,其中环丙沙星的抑菌作用最强,对21株菌的最小抑菌浓度均在0.7813μg/mL以下。21株嗜水气单胞菌均可在24～48 h内体外形成较为稳定的BF,但不同菌株之间形成BF的能力有所不同。嗜水气单胞菌对喹诺酮类药物较为敏感,环丙沙星浓度在1倍MIC以上即可抑制嗜水气单胞菌生物被膜的早期形成,但细菌形成成熟的生物被膜后,较高浓度药物对生物被膜的影响不明显。     

乳源金黄色葡萄球菌生物被膜形成能力及多位点序列分型分析

试验以55株乳源金黄色葡萄球菌为研究对象,通过结晶紫染色法分析其生物被膜形成能力,应用PCR技术检测乳源金黄色葡萄球菌的所携带的耐药基因和生物被膜形成相关基因。结果表明,55株金黄色葡萄球菌中34株生物被膜形成能力较强,17株生物被膜形成能力较弱,4株无生物被膜形成能力;55株细菌中17株(31%)携带mec A耐药基因,17株金黄色葡萄球菌分为9个ST型,均属于已发现的ST型,其中ST97和ST398为优势株。上述来源相近的金黄色葡萄球菌分型后,基本位于ST97和ST98两个大簇,说明该地区引起奶牛乳房炎的细菌型别相对较集中。生物被膜相关基因Ica A、Ica D、Ica R、Eno、Atl、aap、Bap和sig B基因的检出率分别为44%、36%、27%、89%、60%、42%、18%和25%。研究表明,乳源金黄色葡萄球菌的生物被膜形成能力较强,生物被膜形成能力较强的菌株均携带多个生物被膜形成相关基因,说明生物被膜的形成过程可能是受多个基因共同调节。     

金黄色葡萄球菌在生物被膜态与浮游态的转录组差异表达分析

金黄色葡萄球菌是引起奶牛细菌性乳腺炎的主要原因，生物被膜的形成是金黄色葡萄球菌在不利环境条件下持久性存在的关键因素。探索同一株菌在生物被膜态与浮游态生长状态下的耐药性与其生长状态的相关性，可为进一步探究金黄色葡萄球菌的耐药性机制奠定基础。本研究培养了金黄色葡萄球菌的生物被膜，使用光学显微镜和扫描电镜观察其形成过程。测定并比较了9种抗菌药物对32株金黄色葡萄球菌在生物被膜态和浮游态的最小抑菌浓度，并对两种状态下的金黄色葡萄球菌进行转录组学测序，筛选出具有显著性差异的细胞信号通路和表达基因，同时对主要差异表达的基因进行RT-qPCR验证。结果发现，在生物被膜形成前期，随着培养时间的延长，显微镜下观察到的生物被膜态菌聚集面积越来越大，结构也越来越紧密，培养至72 h后，生物被膜逐渐开始分散。MIC测定结果显示浮游态菌的抑菌浓度低于生物被膜态菌。转录组结果显示两种状态菌的差异表达基因共1 512个，其中，生物被膜态菌中上调基因760个，下调752个。GO与KEGG富集分析显示，相比于浮游态菌，生物被膜态菌中与代谢相关的通路显著富集，其次为氨基酸的生物合成和ABC转运蛋白通路。与生物被膜形成相关的基因，如编码ABC转运蛋白的基因表达上调，而与代谢途径相关的基因下调。RT-qPCR验证了10个主要差异基因，其表达差异趋势与转录组测序结果一致。这些差异可能对金黄色葡萄球菌生物被膜态的高耐药性和细菌毒力的研究有所帮助。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.