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91.
Wild birds have repeatedly been found to be involved in the dissemination of enteric bacterial pathogens in the environment. The aim of this study was to determine the occurrence of Salmonella and Campylobacter as well as the antimicrobial resistance in wild Bonelli’s eagles nestlings in Eastern Spain. In addition, we compared the efficiency of two sampling methods (fresh faecal samples from nest and cloacal swabs from nestlings) for detection of both bacteria. A total of 28 nests with 45 nestlings were analysed. In the nest, Salmonella occurrence was 61 ± 9.2%, while Campylobacter occurrence was 11 ± 5.8% (p < 0.05). In the nestlings, Salmonella occurrence was 36 ± 7.1%, while Campylobacter occurrence was 11 ± 4.7% (p < 0.05). Eight Salmonella serovars were identified, and the most frequently isolated were S. Enteritidis, S. Typhimurium, S. Houston, and S. Cerro. Only one Campylobacter species was identified (C. jejuni). Regarding antimicrobial resistance, the Salmonella strains isolated were found to be most frequently resistant to ampicillin and to tigecycline; however, the sole Campylobacter strain recovered was multidrug resistant. In conclusion, this study demonstrated that wild Bonelli’s eagles nestlings are greater carriers of Salmonella than of Campylobacter. Both Salmonella and Campylobacter isolates exhibited antimicrobial resistance. In addition, faecal samples from nests were most reliable for Salmonella detection, while cloacal swab from nestlings were most reliable for Campylobacter detection. 相似文献
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93.
Jaira Snchez‐Pia Miguel Lorenzale María Carmen Fernndez Ana C. Durn Valentín Sans‐Coma Borja Fernndez 《Anatomia, histologia, embryologia》2019,48(5):429-436
Neural crest‐derived melanocytes have been recorded in several parts of the mammalian heart but not in the pulmonary valve. We report here the presence of melanin‐containing cells in the leaflets (cusps) of both the aortic and pulmonary valves. A total of 158 C57BL/6J x Balb/cByJ hybrid mice exhibiting four coat colours, namely black, white, agouti and non‐agouti brown, were examined. We sought for any relationship between the presence of melanocytes in the valves and the coat colour of the animals. The pigmentation levels of the leaflets were accomplished using a scale of five pigment intensities. White mice lacked pigment in the heart. In 10.5% of the remaining animals, there were melanocytes in the pulmonary valve leaflets. Thus, this is the first study to report the presence of such cells in the pulmonary valve of mammals. Melanocytes occurred in the leaflets of the aortic valves of 87.2% of mice. The incidence of melanocytes and the pigmentation level of the leaflets did not statistically differ according to the coat colours of the animals. This disagrees with previous observations, indicating that the amount of melanocytes in the heart reflects that of the skin. The incidence and distribution of melanocytes in aortic and pulmonary valves are consistent with the notion that the formation of the arterial valves is mediated by specific subpopulations of neural crest cells. We hypothesize that melanocytes, even not producing melanin, may be more frequent in the heart than previously thought, exerting presumably an immunological function. 相似文献
94.
Recreational sandboxes for children and dogs can be a source of epidemic ribotypes of Clostridium difficile
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Cristina Orden Carlos Neila José L. Blanco Sergio Álvarez‐Pérez Celine Harmanus Ed J. Kuijper Marta E. García 《Zoonoses and public health》2018,65(1):88-95
Different studies have suggested that the sand of public playgrounds could have a role in the transmission of infections, particularly in children. Furthermore, free access of pets and other animals to the playgrounds might increase such a risk. We studied the presence of Clostridium difficile in 20 pairs of sandboxes for children and dogs located in different playgrounds within the Madrid region (Spain). Clostridium difficile isolation was performed by enrichment and selective culture procedures. The genetic (ribotype and amplified fragment length polymorphism [AFLP]) diversity and antibiotic susceptibility of isolates was also studied. Overall, 52.5% (21/40) of samples were positive for the presence of C. difficile. Eight of the 20 available isolates belonged to the toxigenic ribotypes 014 (n = 5) and 106 (n = 2), both regarded as epidemic, and CD047 (n = 1). The other 12 isolates were non‐toxigenic, and belonged to ribotypes 009 (n = 5), 039 (n = 4), and 067, 151 and CD048 (one isolate each). Nevertheless, all isolates (even those of a same ribotype) were classified into different AFLP genotypes indicating non‐relatedness. In conclusion, our results revealed the presence of epidemic ribotypes of C. difficile in children's and dog's sandboxes located nearby, which constitutes a major health risk. 相似文献
95.
本试验旨在研究布氏乳杆菌(LAB)、黑曲霉(AN)、热带假丝酵母(CT)、枯草芽孢杆菌(BS)与植物乳杆菌(LAP)组合对木薯渣品质的影响,筛选出发酵效果最优的混合菌组合。试验以木薯渣为发酵原料,对LAB、AN、CT、BS与LAP进行不同菌种的菌液以1∶1体积比组合,共设5个不同组合,组合1:LAB+AN+CT+LAP;组合2:LAB+AN+BS+LAP;组合3:LAB+CT+BS+LAP;组合4:AN+CT+BS+LAP;组合5:LAB+AN+CT+BS+LAP;各组合分别添加1%尿素或者1%尿素+0.6%红糖,空白组不添加任何添加剂,对照组Ⅰ添加1%尿素;对照组Ⅱ添加1%尿素+0.6%红糖,各组均用生理盐水调制含水量为65%左右,于聚乙烯薄膜袋中真空发酵10 d。结果表明:1)不同微生物添加剂组合发酵木薯渣对木薯渣营养成分改善效果5菌组合优于4菌组合。其中,LAB+AN+CT+BS+LAP+尿素+红糖组合发酵木薯渣效果最好,与空白组相比显著降低了发酵木薯渣p H(P0.05),提高了乙酸和丙酸含量;中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量均为最低,显著低于空白组和对照组(P0.05);粗蛋白质(CP)含量最高,显著高于空白组和对照组(P0.05)。2)添加相应的菌种+尿素+红糖发酵木薯渣有利于产生丙酸。3)在发酵培养基中添加尿素能显著提高木薯渣CP含量(P0.05)。4)在木薯渣发酵过程中添加尿素+红糖比只添加尿素对木薯渣营养成分改善效果好。综上所述,LAB、AN、CT、BS与LAP组合添加尿素和红糖固态发酵木薯渣,可以有效改善木薯渣品质。 相似文献
96.
北方棉区棉花黄萎病菌落叶型菌系鉴定 总被引:19,自引:1,他引:18
采用RAPD扩增与温室致病性测定2种方法,以黄萎病菌Verticillium dahliae的5个落叶型、7个非落叶型菌系和V.albo-atrum的2个菌系为对照,对采自北方棉区6省(自治区)的34个棉花黄萎病菌菌系进行致病型鉴定。94.1%的菌系在2种鉴定结果中表现一致,与对照菌系相比较,确定其中26个菌系为落叶型菌系,6个菌系为非落叶型菌系。从而证实了黄萎病菌落叶型菌系在北方棉区河北、河南、山东3省的存在,并发现所确定的26个北方落叶型菌系中的22个与来自美国的对照落叶型菌系T9、V44的关系比与来自江苏的对照落叶型菌系VB、V991的关系更近。本实验还初步筛选到2条用于鉴别V.dahliae落叶型与非落叶型菌系的RAPD特异条带OPB-19966和OPM-201691,将它们用于对34个北方菌系的RAPD扩增鉴定,则与温室致病性测定结果的一致性分别为88.2%和94.1%,证明这2条特异条带在鉴定棉花黄萎病菌落叶型菌系上具有一定的实用价值,并为进一步制作特异探针以形成一套简便、准确、规范化的鉴定技术奠定了基础。 相似文献
97.
马桑根瘤内生菌纯培养物的分离、回接及其生物学特性 总被引:1,自引:0,他引:1
多次采用根瘤切片法直接从野生的马桑根瘤中分离内生菌纯培养物均未获成功;但用同样方法从温室里人工接种形成的马桑根瘤中却分离到大量纯培养物。其中273株经盆栽回接后发现有24株能侵染结瘤;少数菌株还通过半固体斜面和珍珠岩盆栽回接成功。对10株纯培养物表型特性的研究表明,它们均具有Frankia的形态和培养特征;生理类型除有A、B两型外,尚出现有一类A、B混合型,其中凡属B型菌株的均能侵染结瘤,A型则不能,两株A、B混合型中有1株能结瘤,另1株却不能;碳、氮源利用特性和其它Frankia基本相似;细胞壁组分既有Ⅲ型也有Ⅱ型;全细胞鉴别性糖大多为木糖和半乳糖,少数菌株只含有半乳糖或木糖,或含有半乳糖、木糖和阿拉伯糖。DNA中G+C mol%为65%~74%。 相似文献
98.
99.
Differences in the effectiveness of reproduction among ten breeding strains of the common carp Cyprinus carpio L. after stimulation of ovulation with carp pituitary homogenate or [(D‐Ala6, Pro9NEt) mGnRH‐a + metoclopramide] (Ovopel)
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This study focused on the reproduction effectiveness of 10 breeding strains of common carp (Polish strains 2, 3, 6; Hungarian strains 0, W, 7; Lithuanian strain B; French strain F; Israeli strain D and Yugoslavian strain J) after stimulation of ovulation with carp pituitary homogenate or Ovopel. The percentage of females with recorded ovulation became higher after Ovopel treatment in as many as eight breeding strains (2, 3, 6, 0, W, B, F, D). The interaction between the spawning agent and the breeding strain was statistically significant (P ≤ 0.05) for the mass of spawn and non‐significant for traits determining the quality of eggs. Among the 10 breeding strains, in 4 (3, 7, B, J) the least‐squares means (LSM) for the weight of egg (g) were higher for fish stimulated with Ovopel. Among the strains tested, in seven (3, W, F, J, 2, 7, B), the LSM for the percentage of living embryos after 36 h incubation were higher for fish treated with Ovopel. The evaluation of reproduction effects based on the values of such parameters as the percentage of ovulating females, weight of eggs (g) and the percentage of live embryos (36 h) showed that after Ovopel treatment the poorer effects were obtained only for strains 6, 0 and D. 相似文献
100.
为了解江苏省猪伪狂犬病病毒(Pseudorabies virus,PRV)野毒株的特点,本研究从2013年采自江苏省宿迁市的疑似PRV感染病料中分离纯化了一株PRV病毒,对其进行了PCR和间接免疫荧光法(IFA)鉴定,并进一步在Vero细胞上测定该分离株的病毒滴度TCID50和一步生长曲线,扩增其gB、gC、gD和gE基因进行序列比对及分子遗传进化分析,并将该分离株分别接种新西兰白兔和15日龄仔猪研究其致病性。结果显示,该病毒为一株PRV,命名为PRV JSSQ2013株,纯化后的病毒滴度为10^7.8 TCID50/ml;生长曲线测定显示在感染20h后病毒滴度即达到最高,为10^8.6 TCID50/ml。与我国近几年分离的PRV变异株序列相比,PRV JSSQ2013株的gB、gC、gD和gE基因核苷酸序列同源性分别为99.5~99.6%、99.5~99.6%、99.5~99.6%和98.7~99.7%,氨基酸序列同源性分别为98.9~99.0%、99.5~99.7%、99.0~99.2%和98.1~99.3%,均高于其与经典毒株(Ea、Fa和SC株)和欧美毒株(Becker、Kaplan、Bartha、Kolchis和NIA3)的同源性;基于gB、gC、gD和gE基因的遗传进化树分析均显示PRV JSSQ2013株与国内近几年分离的PRV变异株属同一分支。该病毒接种新西兰白兔后均出现典型的PR症状,如厌食、兴奋、啃咬或用爪挠接种部位等典型症状,且在48h内全部死亡;接种仔猪后第1天开始出现典型的PR症状,第5天全部死亡。以上结果证实,从江苏省宿迁市采集的疑似PRV感染病料中分离到一株强毒力的PRV变异株。本研究为了解江苏PRV分子流行特征、丰富我国PRV分子流行病学资料及新型疫苗的研制奠定了基础。 相似文献