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Effects of dietary supplementation of probiotic,Clostridium butyricum,on growth performance,immune response,intestinal barrier function,and digestive enzyme activity in broiler chickens challenged with Escherichia coli K88 被引量:45
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作者 Ling Zhang Lingling Zhang +5 位作者 Xiu'an Zhan Xinfu Zeng Lin Zhou Guangtian Cao An'guo Chen Caimei Yang 《Journal of Animal Science and Biotechnology》 CAS CSCD 2016年第1期107-115,共9页
Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varyin... Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum (C. butyficum) on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli (E. coil) K88. Methods: The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment (NC) consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment (PC) consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment (CB) consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment (CS) consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results: The body weight (BW) and average day gain (ADG) in the broilers of CB group were higher (P 〈 0.05) than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher (P 〈 0.05) concentration of tumor necrosis factor-a (TNF-a) at 3 and 7 d post-challenge, and higher (P 〈 0.05) concentration of interleukin-4 (IL-4) at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower (P 〈 0.05) at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower (P 〈 0.05) at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher (P 〈 0.05) jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In comparison to PC birds, the CB birds had lower (P 〈 0.05) jejunum crypt depth during the whole experiment. The birds in CB or CS treatment group had higher (P 〈 0.05) activities of amylase and protease at 3, 7, and 14 d post-challenge, and higher (P 〈 0.05) activity of lipase at 3, 7 d post-challenge than PC birds. 展开更多
关键词 Broiler chickens Clostridium butyricum Digestive enzyme activity escherichia coli k88 Growth performance Immune response Intestinal barrier
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Response to an Escherichia coli K88 oral challenge and productivity of weanling pigs receiving a dietary nucleotides supplement 被引量:3
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作者 Hanlin Li Pinyao Zhao +2 位作者 Yan Lei Tianshui Li InHo Kim 《Journal of Animal Science and Biotechnology》 CAS CSCD 2016年第1期86-94,共9页
Background: Dietary nucleotides, considered as antibiotics alternative, were shown to have positive effects on intestinal hyperaemia, systemic immunity, small-intestinal growth, and hepatic composition in pigs. Howev... Background: Dietary nucleotides, considered as antibiotics alternative, were shown to have positive effects on intestinal hyperaemia, systemic immunity, small-intestinal growth, and hepatic composition in pigs. However, there is no previous research on nucleotide supplementation in weanling pigs under an oral challenged E. coil K88. Therefore, 2 experiments were conducted to investigate the effects of dietary nucleotides on weanling pig growth performance, nutrient digestibility, fecal score, and blood profile after being orally challenged with E. coli K88. Methods: In Exp. 1, a total of 140 weanling pigs [8.33 ± 0.33 kg of body weight (BW), 28-d old] were used in this 42-d feeding trial. Pigs were distributed into 1 of 4 treatments, 5 pigs/pen (3 barrows and 2 gilts) and 7 pens/treatment. Treatments were a control basal diet (CON) or the CON supplemented with 150 (R150), 220 (R220), or 275 (R275) mg/kg to give the three treatment diets. In Exp. 2, 28 weanling pigs (BW = 8.40 ± 0.22 kg, 28-d old) were distributed into 1 of 4 treatments to give 1 pig/pen and 7 pens/treatment in a 42-d feeding and challenge trial. Dietary treatments were the same as in Exp. 1. 0n d 14, all those pigs (BW= 13.3±0.15 kg, 42-d old) were orally dosed with 1.5 mL suspension containing 10 cfu/mL of E. coli K88. Twenty four hours after challenge, blood and excreta samples were collected from each pigs for analysis. Fecal scores were measured on d 7, 14, 21, and 28 of the study. Results: In Exp. 1, overall BW, average daily gain (ADG), gain/feed (G/F) ratio, and nutrient digestibilities were lower (P 〈 0.05) in CON group compared with the nucleotides fed pigs. In Exp. 2, after challenge, IgA, IgM, and IGF-I were higher (P〈 0.05) in the nucleotide groups compared with CON. However, the nucleotide groups had lower (P 〈 0.05) cortisol and TNF-o compared with CON. Fecal E. coil counts and fecal score for the nucleotide groups were lower (P 〈 0.05) than for CON. Conclusions: In conclusion, dietary nucleotides supplementation could improve growth performance, nutrient digestibility, immune status, microbial balance, reduce diarrhea, and provide protection against enterotoxigenic E. coli K88 infection in weanling pigs. 展开更多
关键词 Dietary nucleotides escherichia coli k88 challenge Growth performance IMMUNITY Nutrientdigestibility Weanling pigs
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Enterococcus faecium NCIMB 10415 administration improves the intestinal health and immunity in neonatal piglets infected by enterotoxigenic Escherichia coli K88 被引量:7
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作者 Xie Peng Ru Wang +13 位作者 Liang Hu Qiang Zhou Yang Liu Min Yang Zhengfeng Fang Yan Lin Shengyu Xu Bin Feng Jian Li Xuemei Jiang Yong Zhuo Hua Li De Wu Lianqiang Che 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第1期132-146,共15页
Background:This study aimed to investigate the effects of oral administration of Enterococcus faecium NCIMB10415(E.faecium)on intestinal development,immunological parameters and gut microbiota of neonatal piglets chal... Background:This study aimed to investigate the effects of oral administration of Enterococcus faecium NCIMB10415(E.faecium)on intestinal development,immunological parameters and gut microbiota of neonatal piglets challenged with enterotoxigenic Escherichia coli K88(ETEC).A total of 961-day-old sow-reared piglets were randomly assigned to 2 groups,with 48 piglets in each group.The piglets were from 16 litters(6 piglets each litter),and 3 piglets each litter were allocated to the E.faecium-supplemented(PRO)group,while the other 3 piglets were allocated to the control(CON)group.After colostrum intake,piglets in the PRO group were orally administrated with 3×10~9 CFU E.faecium per day for a period of one week.On day 8,one piglet per litter from each group was challenged(CON+ETEC,PRO+ETEC)or not(CON-ETEC,PRO-ETEC)with ETEC in a 2×2 factorial arrangement of treatments.On day 10(2 days after challenge),blood and tissue samples were obtained from piglets.Results:Before ETEC challenge,there were no significant differences for the average daily gain(ADG)and fecal score between the two groups of piglets.After ETEC challenge,the challenged piglets had greater fecal score compared to the non-challenged piglets,whereas E.faecium administration was able to decrease the fecal score.Piglets challenged with ETEC had shorter villous height,deeper crypt depth,and reduced number of goblet cells in the jejunum and decreased m RNA abundance of claudin-1 in the ileum,whereas increased the percentage of lymphocytes,concentrations of IL-1βin the plasma and TNF-αin the ileal mucosa,as well as increased the m RNA abundances of innate immunity-related genes in the ileum tissue.These deleterious effects caused by ETEC were partly alleviated by feeding E.faecium.In addition,piglets in PRO-ETEC group had decreased the percentage of CD8^+T cells of the peripheral blood when compared to those in CON-ETEC group.Moreover,E.faecium administration increased Verrucomicrobia at phylum level and decreased Bilophila at genus level.Conclusions:These results suggest that oral administration of E.faecium alleviated the intestinal injury and diarrhea severity of neonatal piglets challenged by ETEC,partly through improving the intestinal microbiota and immune response.This offers a potential strategy of dietary intervention against intestinal impairment by ETEC in neonatal piglets. 展开更多
关键词 ENTEROCOCCUS FAECIUM Enterotoxigenic escherichia coli k88 Gut microbiota IMMUNITY Intestine NEONATAL PIGLETS
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Effects of casein glycomacropeptide supplementation on growth performance,intestinal morphology, intestinal barrier permeability and inflammatory responses in Escherichia coli K88 challenged piglets 被引量:8
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作者 Yili Rong Zeqing Lu +3 位作者 Haiwen Zhang Lin Zhang Deguang Song Yizhen Wang 《Animal Nutrition》 SCIE 2015年第2期54-59,共6页
Casein glycomacropeptide(CGMP) is a bioactive peptide derived from milk with multiple functions. This study was aimed at evaluating the effects of CGMP as a potential feed additive on growth performance,intestinal mor... Casein glycomacropeptide(CGMP) is a bioactive peptide derived from milk with multiple functions. This study was aimed at evaluating the effects of CGMP as a potential feed additive on growth performance,intestinal morphology, intestinal barrier permeability and inflammatory responses of Escherichia coli K88(E. coli K88) challenged piglets. Eighteen weaning piglets were randomly assigned to three groups.Control group and K88 challenged group received a basal diet, and CGMP treated group received the basal diet supplemented with 1% of CGMP powder. The trail lasted for 12 days, K88 was orally administered to the piglets of K88 challenged group and CGMP treated group on days 8-10. The results showed that the diet containing 1% CGMP significantly alleviated the decrease in average daily gain(P <0.05),increase in pathogenic bacteria amounts in intestinal contents(P < 0.05), intestinal morphology(P > 0.05) and barrier permeability damage(P < 0.05), and acute inflammatory response(P < 0.05)induced by E. coli K88 infection. In conclusion, CGMP supplementation in the diet protected the weaning piglets against E. coli K88 infection. 展开更多
关键词 Casein glycomacropeptide Weaning piglets escherichia coli k88 Growth performance
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Combined effects of chitosan and microencapsulated Enterococcus faecalis CG1.0007 probiotic supplementation on performance and diarrhea incidences in enterotoxigenic Escherichia coli K88^+ challenged piglets 被引量:5
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作者 Kolawole Aluko Deepak E.Velayudhan +3 位作者 Ehsan Khafipour Aike Li Yulong Yin Martin Nyachoti 《Animal Nutrition》 SCIE 2017年第4期366-371,共6页
The aim of this study was to investigate the combined effects of chitosan oligosaccharide(COS) and a microencapsulated Enterococcus faecalis CG1.0007 probiotic(PRO) on growth performance and diarrhea incidences in ent... The aim of this study was to investigate the combined effects of chitosan oligosaccharide(COS) and a microencapsulated Enterococcus faecalis CG1.0007 probiotic(PRO) on growth performance and diarrhea incidences in enterotoxigenic Escherichia coli(ETEC) K88^+ challenged piglets in a 14-d study. Thirty piglets,7.19 ± 0.52 kg initial BW weaned at 21 ± 1 d.were allotted to 5 treatment groups(n = 6)consisting of a corn-soybean meal diet with no additive(negative control, NC), NC + 0.25% chlortetracycline(positive control, PC), NC + 400 mg/kg COS(COS), NC + 100 mg/kg PRO(PRO) and NC + a combination of COS and PRO(CPRO). Pigs were individually housed in cages, acclimated to treatments for a 7-d period and had ad libitum access to feed and water throughout the study, On d 8, pigs were weighed, blood samples were collected, and then orally challenged with 6 mL(1 ×10^(11) cfu/mL) of freshly grown ETEC inoculum. During post-challenge period, blood was sampled at 24 and 48 h to determine plasma urea nitrogen(PUN), and diarrhea incidences and fecal consistency scores were recorded from d 9 to 12. On d 14, all pigs were weighed and then euthanized to obtain intestinal tissue samples for histomorphometric measurements. Growth performance responses were similar among treatments during the pre-and post-challenge periods. There were no significant differences in PUN content, incidences of diarrhea, and fecal consistency scores among treatments. The intestinal histomorphology results did not differ significantly among treatments except for PC with increased(P = 0.0001) villus:crypt ratio compared with the NC. Under the conditions of the present study, it can be concluded that supplementation of piglet diets with 400 mg/kg COS, 100 mg/kg microencapsulated PRO or their combination did not significantly improve piglet growth performance both during the pre-and post-ETEC K88+ oral inoculation. Also, there were no significant reduction of incidences and severity of diarrhea after challenge compared with the control group. 展开更多
关键词 Enterotoxigenic escherichia coli k88^+ Chitosan oligosaccharide Enterococcus faecalis CG1 0007 probiotic Growth performance Diarrhea incidences PIGLETS
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产肠毒素性大肠杆菌K88的致病特性及其益生菌的筛选 被引量:7
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作者 张赛群 朱红梅 +2 位作者 周涵韬 黄素芳 刘波 《中国兽医科学》 CAS CSCD 北大核心 2008年第5期386-392,共7页
在获得绿色荧光蛋白(GFP)标记的菌株K88-GFP并证明其与K88具有遗传同质性的基础上,以K88-GFP为致病菌,腹腔注射侵染小鼠,在不同时间进行眼球采血,测定血液生理生化指标,并采取不同器官或组织,培养后利用紫外光激发K88-GFP的绿色荧光,观... 在获得绿色荧光蛋白(GFP)标记的菌株K88-GFP并证明其与K88具有遗传同质性的基础上,以K88-GFP为致病菌,腹腔注射侵染小鼠,在不同时间进行眼球采血,测定血液生理生化指标,并采取不同器官或组织,培养后利用紫外光激发K88-GFP的绿色荧光,观察计数这种产肠毒素性大肠杆菌(ETEC)在小鼠体内的分布。同时通过体外抑制和活体饲喂试验,进行了益生菌的筛选。结果证实,ETEC致病菌具有较强的侵袭性,它可以侵袭小鼠肝、肾、心、肺及脑、肌肉等器官和组织,尤其可对肝、肾造成严重的损伤;筛选得到益生菌株PB JK-2,在体内外均对K88具有较好的抑制作用。 展开更多
关键词 产肠毒素性大肠杆菌 k88 k88-GFP致病特性 益生菌
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大肠杆菌K88菌毛蛋白faeG亚基基因克隆及表达 被引量:6
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作者 徐建生 成大荣 +1 位作者 任士飞 孙怀昌 《扬州大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2005年第3期1-4,共4页
利用PCR技术,从致仔猪黄痢的大肠杆菌中扩增不含信号肽序列的K 88菌毛蛋白faeG亚基基因片段,将其克隆到表达载体pGEX-6P-1中,构建该基因的原核表达载体pGEX-F aeG,通过测序证明序列正确后,导入大肠杆菌BL 21,得到工程菌株PGEX-F aeG。I... 利用PCR技术,从致仔猪黄痢的大肠杆菌中扩增不含信号肽序列的K 88菌毛蛋白faeG亚基基因片段,将其克隆到表达载体pGEX-6P-1中,构建该基因的原核表达载体pGEX-F aeG,通过测序证明序列正确后,导入大肠杆菌BL 21,得到工程菌株PGEX-F aeG。IPTG诱导表达,SDS-PAGE分析结果表明,融合蛋白(约53 ku)在大肠杆菌BL 21中得到高效表达,表达产物约占菌体蛋白的35%,免疫印记结果表明此融合蛋白与K 88单抗反应。 展开更多
关键词 大肠杆菌 k88菌毛 克隆 表达
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检测K88^+肠毒素性大肠杆菌PCR方法的建立 被引量:10
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作者 陆桂平 华荣虹 +1 位作者 张书霞 何孔旺 《畜牧与兽医》 北大核心 2002年第12期7-9,共3页
以K8 8菌毛结构基因保守序列为靶序列 ,设计合成了一对可扩增长 2 0 1bp的目的片段的引物 ,成功地建立了检测肠毒素性大肠杆菌(ETEC)K88菌毛基因的PCR方法。进行了PCR方法的特异性试验和敏感性试验。对K99+ ,F41 + ,987p+ 参考菌株和鼠... 以K8 8菌毛结构基因保守序列为靶序列 ,设计合成了一对可扩增长 2 0 1bp的目的片段的引物 ,成功地建立了检测肠毒素性大肠杆菌(ETEC)K88菌毛基因的PCR方法。进行了PCR方法的特异性试验和敏感性试验。对K99+ ,F41 + ,987p+ 参考菌株和鼠伤寒沙门氏杆菌 ,链球菌 ,金黄色葡萄球菌和猪肺疫巴氏杆菌的检测结果均为阴性 ;该检测方法的敏感度可达 1 0个细菌。用此方法对 1 0株腹泻仔猪粪便分离物进行检测 ,结果有 2株阳性 ;与血清学检测的结果一致。结果表明此方法特异性和敏感性都很高 ,可用于临床K88+ 展开更多
关键词 肠毒素性大肠杆菌 k88菌毛基因 PCR 检测方法 腹泻
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产肠毒素大肠杆菌K88ab/K88ad菌毛操纵子fae全基因的克隆、表达及生物学活性的初步研究 被引量:2
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作者 郁磊 吴娟 +1 位作者 朱军 朱国强 《中国预防兽医学报》 CAS CSCD 北大核心 2013年第1期23-27,共5页
为研究K88ab/K88ad菌毛对细胞的黏附作用,本研究分别以产肠毒素E.coli(ETEC)K88ab C83901株和K88ad C83903株基因组DNA为模板,采用PCR技术扩增这两种K88菌毛操纵子fae基因(均约7.9 kb)。将其分别克隆于表达质粒pBR322中构建pBR-K88ab和p... 为研究K88ab/K88ad菌毛对细胞的黏附作用,本研究分别以产肠毒素E.coli(ETEC)K88ab C83901株和K88ad C83903株基因组DNA为模板,采用PCR技术扩增这两种K88菌毛操纵子fae基因(均约7.9 kb)。将其分别克隆于表达质粒pBR322中构建pBR-K88ab和pBR-K88ad重组质粒,并将其分别转化至不含任何菌毛的E.coli SE5000株中。该重组菌能够分别与鼠抗K88菌毛阳性血清和抗K88菌毛单克隆抗体(MAb)产生凝集反应;在电镜下观察到重组菌表面大量表达K88菌毛。采用热抽提法提取其体外表达的K88ab和K88ad菌毛,SDS-PAGE电泳检测结果显示,菌毛蛋白的分子量约为26 ku。玻板凝集试验和western blot结果表明:重组表达的K88ab及K88ad菌毛与K88+参考株菌毛均能够被抗K88菌毛阳性血清和MAb识别。以猪小肠上皮细胞系IPEC-J2为模型进行黏附和黏附抑制试验,结果表明表达K88菌毛的重组菌及K88+参考株均能够黏附于IPEC-J2上皮细胞表面;而且阳性血清和MAb能够有效抑制重组菌或K88+参考株对猪小肠上皮细胞系的黏附结合。 展开更多
关键词 产肠毒素大肠杆菌 k88菌毛 克隆 生物活性
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黏附性菌毛K88的研究新进展 被引量:3
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作者 程碧军 李鹏 金升藻 《安徽农业科学》 CAS 北大核心 2007年第2期446-447,449,共3页
综述了近年来国内外黏附性菌毛K88的研究进展。
关键词 大肠杆菌 菌毛 k88
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应用K88-K99 PCR试剂盒检测大肠杆菌研究 被引量:2
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作者 李鹏 王家乡 +2 位作者 戴鼎震 程太平 施秋艳 《湖北农学院学报》 2003年第2期103-104,145,共3页
用研制的K88-K99 PCR诊断试剂盒对湖北省和江苏省的5个猪场238个病猪粪便进行了检测。扩增结果是K88检出率92.0%(219/238);K99检出率89.1%(212/238);阳性对照检出率100%,阴性对照未扩增到目的DNA片段。结果表明,运用PCR试剂盒检测具... 用研制的K88-K99 PCR诊断试剂盒对湖北省和江苏省的5个猪场238个病猪粪便进行了检测。扩增结果是K88检出率92.0%(219/238);K99检出率89.1%(212/238);阳性对照检出率100%,阴性对照未扩增到目的DNA片段。结果表明,运用PCR试剂盒检测具有快速、特异的优点,可同时处理大量样品,且可直接对粪便样品进行检测,值得进一步推广。 展开更多
关键词 应用 k88-K99菌毛 PCR试剂盒 检测技术 大肠杆菌 仔猪 腹泻
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猪大肠杆菌K88-K99 PCR诊断试剂盒研究 被引量:3
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作者 李鹏 戴鼎震 +1 位作者 王家乡 程太平 《湖北农学院学报》 2002年第6期501-503,510,共4页
根据已成功扩增的大肠杆菌K88及K99菌毛蛋白结构基因PCR反应 ,进行PCR反应体系的优化。将 2种菌毛蛋白结构基因的扩增引物混合进行PCR ,同时检测K88及K99菌毛蛋白结构基因。经优化试验 ,筛选出 5 0 μLPCR反应体系中各成分的最适用量为 ... 根据已成功扩增的大肠杆菌K88及K99菌毛蛋白结构基因PCR反应 ,进行PCR反应体系的优化。将 2种菌毛蛋白结构基因的扩增引物混合进行PCR ,同时检测K88及K99菌毛蛋白结构基因。经优化试验 ,筛选出 5 0 μLPCR反应体系中各成分的最适用量为 :Mg2 + 浓度 2mmol L ,Taq酶 5U ,dNTPs 2 0 0mmol L ,每条引物 5 0pmol,模板量 1 0 0CFU ,并研制成功用于临床检测的PCR诊断试剂盒。 展开更多
关键词 诊断试剂盒 猪大肠杆菌 k88-K99菌毛 PCR试剂盒 优化试验
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检验用大肠杆菌K88纤毛抗原的纯化及其单因子血清制备与质量控制方法研究
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作者 彭国瑞 蒋菲 +5 位作者 王秀丽 彭小兵 李建 李旭妮 李俊平 张媛 《中国兽医杂志》 CAS 北大核心 2020年第8期12-15,I0002,共5页
为研究兽用生物制品检验用大肠杆菌K88纤毛抗原的纯化及其单因子血清制备与质量控制方法。通过生物反应器发酵含K88抗原的大肠杆菌,机械脱纤处理获得K88纤毛抗原,经柠檬酸等电点沉淀和饱和硫酸铵梯度盐析以及透析处理纯化抗原,免疫家兔... 为研究兽用生物制品检验用大肠杆菌K88纤毛抗原的纯化及其单因子血清制备与质量控制方法。通过生物反应器发酵含K88抗原的大肠杆菌,机械脱纤处理获得K88纤毛抗原,经柠檬酸等电点沉淀和饱和硫酸铵梯度盐析以及透析处理纯化抗原,免疫家兔3次制备单因子血清并进行质量控制。结果显示,所纯化的K88纤毛抗原纯度能达到85%,每升发酵菌液可得到提纯抗原33.3 mg,免疫家兔血清琼扩效价可达到1∶128。表明该纤毛抗原制备和纯化及其单因子血清制备方法简易,纯度和产率较高,质量可控且易于批量制备。 展开更多
关键词 大肠杆菌 k88纤毛抗原 纯化 血清
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饲用凝结芽孢杆菌对感染产肠毒素大肠杆菌K88断奶仔猪生长性能和肠道健康的影响 被引量:18
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作者 柳成东 肖明霞 +3 位作者 赵平 李琦华 白华毅 程志斌 《动物营养学报》 CAS CSCD 北大核心 2021年第8期4373-4383,共11页
本文旨在研究饲用凝结芽孢杆菌对感染产肠毒素大肠杆菌(ETEC)K88断奶仔猪生长性能和肠道菌群、形态及细胞因子表达的影响。试验选用32头25日龄断奶的健康“杜×长×大”商品公猪,按照初始体重一致原则分成4个组,每组8个重复,单... 本文旨在研究饲用凝结芽孢杆菌对感染产肠毒素大肠杆菌(ETEC)K88断奶仔猪生长性能和肠道菌群、形态及细胞因子表达的影响。试验选用32头25日龄断奶的健康“杜×长×大”商品公猪,按照初始体重一致原则分成4个组,每组8个重复,单笼饲养。ETEC K88感染前7 d,2个组饲喂基础饲粮(BD组),另外2个组饲喂在基础饲粮中添加1.0×10^(7) CFU/g凝结芽孢杆菌的饲粮(PD组)。第8天起,开展2×2双因素试验,4个组设计如下:1)NCH+BD组,口服生理盐水、饲喂基础饲粮;2)NCH+PD组,口服生理盐水、饲喂添加凝结芽孢杆菌饲粮;3)CH+BD组,口服ETEC K88、饲喂基础饲粮;4)CH+PD组,口服ETEC K88、饲喂添加凝结芽孢杆菌饲粮。试验猪口服5 mL ETEC K88(活菌数1.0×10^(9) CFU/mL)或5 mL 0.9%生理盐水,持续3 d。试验用凝结芽孢杆菌是经体外牛津杯法确定的1株对ETEC K88具有良好抑菌效果的菌株,添加量1.0×10^(7) CFU/g。试验第11天,取仔猪空肠、回肠、盲肠及食糜样本,测定肠道菌群、形态及细胞因子表达量。结果表明:1)ETEC K88感染处理显著降低断奶仔猪平均日增重和平均日采食量、空肠和盲肠食糜中乳酸杆菌数量、空肠和回肠绒毛高度以及空肠黏膜白细胞介素-10(IL-10)mRNA表达量(P<0.05);同时,显著提高断奶仔猪料重比和腹泻指数、空肠和盲肠食糜中大肠杆菌数量、空肠和回肠隐窝深度以及空肠黏膜白细胞介素-6(IL-6)mRNA表达量(P<0.05)。2)饲用凝结芽孢杆菌处理显著提高断奶仔猪平均日增重和平均日采食量、空肠和盲肠食糜中乳酸杆菌数量、空肠和回肠绒毛高度以及空肠黏膜IL-10 mRNA表达量(P<0.05);同时,显著降低断奶仔猪料重比和腹泻指数、空肠和盲肠食糜中大肠杆菌数量、空肠和回肠隐窝深度以及空肠黏膜IL-6 mRNA表达量(P<0.05)。3)除腹泻指数外,ETEC K88感染处理与饲用凝结芽孢杆菌处理之间对其他指标均无显著互作效应(P>0.05)。结果提示,无论是否ETEC K88感染处理,饲用凝结芽孢杆菌均可通过平衡肠道菌群、维持肠道正常形态和缓解肠道炎症反应,改善断奶仔猪生长性能。 展开更多
关键词 凝结芽孢杆菌 产肠毒素大肠杆菌k88感染 断奶仔猪 生长性能 肠道健康
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非预增菌可视化快速检测食品中肠毒素大肠杆菌K88的研究 被引量:2
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作者 付梦玉 吴云 +2 位作者 林丽萍 王瑾 吴国平 《江西农业大学学报》 CAS CSCD 北大核心 2017年第3期587-593,共7页
本研究运用肠毒素大肠杆菌K88(E.coli K88)特异的适配体结合纳米金和银增强技术,建立了E.coli K88一种可视化快速检测技术,实现约2 h检测E.coli K88达10 CFU/反应的灵敏度。通过人工模拟E.coli K88污染25 g蔬菜、牛奶或猪肉等食品原料,... 本研究运用肠毒素大肠杆菌K88(E.coli K88)特异的适配体结合纳米金和银增强技术,建立了E.coli K88一种可视化快速检测技术,实现约2 h检测E.coli K88达10 CFU/反应的灵敏度。通过人工模拟E.coli K88污染25 g蔬菜、牛奶或猪肉等食品原料,采用该可视化快速检测技术进行非预增菌直接检测,结果显示检测灵敏度达100 CFU/m L(或g),检测需时约2 h,在1.0×102~1.0×105CFU/m L(或g)的E.coli K88污染浓度范围内,样品A630nm吸光值与目标菌污染浓度对数值呈线性关系,相关系数R20.97以上。研究结果表明,E.coli K88可视化检测方法可用于食品样品E.coli K88污染非预增菌的快速、灵敏检测分析。 展开更多
关键词 肠毒素大肠杆菌k88 适配体 纳米金 人工模拟污染食品 非预增菌
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共表达ETECK99、K88菌毛蛋白重组干酪乳杆菌的构建 被引量:4
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作者 温丽娟 王桂华 +2 位作者 侯喜林 余丽芸 王萌 《黑龙江八一农垦大学学报》 2011年第3期34-39,共6页
将PCR扩增的K99和K88-LTB基因片段串联插入到干酪乳杆菌细胞表面表达载体pLA中,构建了重组表达载体pLA-K99-K88-LTB,将其电转化干酪乳杆菌CICC 6 105,获得了表达融合蛋白pLA-K99-K88-LTB的重组干酪乳杆菌表达系统。重组干酪乳杆菌在MRS... 将PCR扩增的K99和K88-LTB基因片段串联插入到干酪乳杆菌细胞表面表达载体pLA中,构建了重组表达载体pLA-K99-K88-LTB,将其电转化干酪乳杆菌CICC 6 105,获得了表达融合蛋白pLA-K99-K88-LTB的重组干酪乳杆菌表达系统。重组干酪乳杆菌在MRS培养基中表达后,经SDS-PAGE检测,约有90 KDa的融合蛋白得到表达,蛋白大小与理论值相符合。Western-blot分析表明表达的蛋白可被鼠源K99,K88抗血清所识别。间接免疫荧光技术和流式细胞术的结果表明,融合蛋白成功地利用多聚谷氨酸跨膜蛋白pgsA基因展示在干酪乳杆菌菌体表面。 展开更多
关键词 产肠毒素性大肠杆菌 k88菌毛蛋白 K99菌毛蛋白 干酪乳杆菌
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腐殖酸钠对肠产毒素性大肠杆菌K88感染小鼠肠道损伤的保护作用 被引量:1
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作者 王栋 何炎峻 +3 位作者 柳可欣 邓守翔 黄思琪 刘云 《动物营养学报》 CAS CSCD 北大核心 2022年第6期3991-4002,共12页
本研究旨在探究腐殖酸钠(HNa)对肠产毒素性大肠杆菌K88(ETEC K88)感染小鼠肠道损伤的保护作用。选取健康的无特定病原体(SPF)级雌性昆明小鼠30只,随机分为3组,对照组、模型组(ETEC组)、HNa干预组(ETEC+HNa组),每组10只。对照组和ETEC组... 本研究旨在探究腐殖酸钠(HNa)对肠产毒素性大肠杆菌K88(ETEC K88)感染小鼠肠道损伤的保护作用。选取健康的无特定病原体(SPF)级雌性昆明小鼠30只,随机分为3组,对照组、模型组(ETEC组)、HNa干预组(ETEC+HNa组),每组10只。对照组和ETEC组小鼠每天灌胃0.2 mL生理盐水,ETEC+HNa组小鼠每天灌胃0.2 mL 5%HNa;试验第8天,ETEC和ETEC+HNa组小鼠灌胃0.2 mL 5×10^(10)CFU/mL ETEC K88。试验期10 d。采用苏木精-伊红(HE)染色法观察空肠病理变化,采用酶联免疫吸附测定(ELISA)法检测血清炎症因子含量,采用实时荧光定量PCR(qPCR)法检测肠道屏障相关蛋白的mRNA表达,采用蛋白免疫印迹(Western blot)法检测空肠紧密连接、黏附连接、肠道组织炎性小体和细胞凋亡相关蛋白的表达。结果表明:1)与对照组和ETEC+HNa组,ETEC组小鼠体重及空肠绒毛高度、绒毛高度/隐窝深度显著降低(P<0.05)。2)与对照组和ETEC+HNa组相比,ETEC组小鼠血液白细胞、单核细胞、粒细胞数量及血清白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、二胺氧化酶(DAO)、D-乳酸(D-Lac)含量显著升高(P<0.05),血清白细胞介素-4(IL-4)和白细胞介素-10(IL-10)含量显著降低(P<0.05)。3)与对照组和ETEC+HNa组相比,ETEC组空肠闭合蛋白(Occludin)、封闭蛋白-1(Claudin-1)、上皮型钙黏蛋白(E-cadherin)和黏蛋白-2(MUC-2)的mRNA相对表达量显著降低(P<0.05),空肠Claudin-1、ZO-1、E-cadherin和MUC-2的蛋白表达量也显著降低(P<0.05)。4)与对照组和ETEC+HNa组相比,ETEC组空肠核因子-κB(NF-κB)、核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)、半胱天冬蛋白酶-1(Caspase-1)、白细胞介素-1β(IL-1β)和B细胞淋巴瘤/白血病-2相关X蛋白(Bax)的蛋白表达量显著升高(P<0.05),空肠B细胞淋巴瘤/白血病-2(Bcl-2)的蛋白表达量显著降低(P<0.05)。5)与对照组相比,ETEC组粪便大肠杆菌数量显著增加(P<0.05),粪便乳酸菌数量则显著降低(P<0.05)。与ETEC组相比,ETEC+HNa组粪便大肠杆菌显著降低(P<0.05)。由此可见,HNa可以通过抑制肠道组织炎性小体激活、肠道上皮细胞凋亡以及上调肠道屏障相关蛋白的表达缓解ETEC K88感染引起的肠道损伤。 展开更多
关键词 腐殖酸钠 肠产毒素性大肠杆菌k88 炎性小体 肠道屏障 小鼠
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连梅止痢中药制剂对大肠埃希菌K88感染仔猪的疗效
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作者 刘勇亮 陈波 +4 位作者 刘明刚 徐毓琴 戴茜茜 谷笑笑 潘康成 《浙江农业学报》 CSCD 北大核心 2016年第9期1493-1500,共8页
探讨连梅止痢中药制剂对大肠埃希菌K88感染的仔猪腹泻的疗效。72头21日龄初始体质量平均为(4.41±0.01)kg的仔猪被分为6组:空白对照组、发病组、低剂量(0.5 m L·kg-1BW)、中剂量(1.0 m L·kg-1BW)、高剂量组(1.5 m L·... 探讨连梅止痢中药制剂对大肠埃希菌K88感染的仔猪腹泻的疗效。72头21日龄初始体质量平均为(4.41±0.01)kg的仔猪被分为6组:空白对照组、发病组、低剂量(0.5 m L·kg-1BW)、中剂量(1.0 m L·kg-1BW)、高剂量组(1.5 m L·kg-1BW)及抗生素组(0.2%恩诺沙星2 m L·头-1)。给断奶仔猪灌服一定数量的大肠埃希菌K88建立腹泻模型,利用乌梅、黄连、诃子以及秦皮原料制备的连梅止痢中药制剂(含生药1 g·m L-1)对发病猪进行治疗,观察该中药制剂对腹泻病的疗效。结果表明,该中药制剂对仔猪大肠埃希菌腹泻的治愈率为80%。实时定量PCR检测结果表明,在用药的整个阶段中剂量组仔猪粪便中的大肠埃希菌K88平均数量与发病组相比显著减少(P<0.05),其他剂量组与发病组相比差异不显著(P>0.05)。从仔猪肠道形态上观察,抗生素组和中剂量组仔猪肠道组织结构基本完整。经过生存分析发现,中剂量中药制剂与发病组相比能显著提高仔猪生存率(P<0.05)。发病组生存曲线相比其他组的陡峭,而中剂量组的曲线最平缓,中药制剂能降低仔猪的死亡率。 展开更多
关键词 中药制剂 断奶仔猪 腹泻模型 大肠埃希菌k88 实时定量PCR 肠道形态 生存分析
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共表达ETEC 987P、K88重组乳杆菌构建及其免疫原性分析
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作者 杨雨晴 李树东 +6 位作者 孙晓莹 陈小燕 白永飞 李颖 蔡昌福 余丽芸 侯喜林 《黑龙江八一农垦大学学报》 2022年第2期44-51,106,共9页
构建表达产肠毒素大肠杆菌(Enterotoxigenic Escherichia coli,ETEC)987P和K88蛋白的重组干酪乳杆菌,并对重组干酪乳杆菌免疫原性进行分析。通过PCR构建重组质粒pLA-987P-K88并电转化至干酪乳杆菌6105后进行表达,通过Western blot、间... 构建表达产肠毒素大肠杆菌(Enterotoxigenic Escherichia coli,ETEC)987P和K88蛋白的重组干酪乳杆菌,并对重组干酪乳杆菌免疫原性进行分析。通过PCR构建重组质粒pLA-987P-K88并电转化至干酪乳杆菌6105后进行表达,通过Western blot、间接免疫荧光和流式细胞术检测目的蛋白的表达情况。将重组干酪乳杆菌灌胃免疫BALB/c小鼠,三次免疫后用ELISA检测小鼠血清中IgG抗体和肠冲洗液中sIgA抗体水平,采用CCK-8检测淋巴细胞的增殖情况,用C83916(987P)株和C83902(K88)株进行攻毒保护性试验检测其保护率。结果显示,重组干酪乳杆菌成功表达987P-K88融合蛋白,小鼠免疫重组菌后血清中IgG抗体水平和肠冲洗液sIgA水平显著升高,细胞免疫水平明显增长,攻毒保护性试验结果显示,重组菌能同时对C83916(987P)株和C83902(K88)株具有良好的保护作用。 展开更多
关键词 产肠毒素大肠杆菌 987P k88 重组干酪乳杆菌 免疫原性
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大肠杆菌K88菌毛蛋白发酵工艺的初步研究
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作者 杨春梅 《生命科学研究》 CAS CSCD 2006年第S2期72-77,共6页
采用液体培养基包括牛肉膏蛋白胨培养基和强化营养肉汤培养基对大肠杆菌K88进行发酵培养,采用不同摇瓶培养时间和不同pH值的培养基观察发酵结果,研究菌体和菌毛生产量的相关性,并通过紫外分光光度计UV751于600nm处测量菌体OD值以对菌种... 采用液体培养基包括牛肉膏蛋白胨培养基和强化营养肉汤培养基对大肠杆菌K88进行发酵培养,采用不同摇瓶培养时间和不同pH值的培养基观察发酵结果,研究菌体和菌毛生产量的相关性,并通过紫外分光光度计UV751于600nm处测量菌体OD值以对菌种发酵情况进行检测.热激分离菌体和菌毛蛋白,(NH4)2SO4盐析分离纯化K88菌毛蛋白并用分光光度计于280nm处测定其OD值.透析后经SDSP-AGE检测菌毛蛋白纯度.根据实验结果优化发酵培养条件,确定菌种的最佳发酵工艺,以收获最多的K88菌毛蛋白.经过实验研究,最终确定了大肠杆菌K88在pH值为6.5、转速为250r/min的条件下发酵18个h,菌体和菌毛生产量均达到高峰,同时得出菌毛蛋白和菌体成正相关. 展开更多
关键词 大肠杆菌 k88菌毛蛋白 发酵 工艺优化
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