AIM： To detect Salmonella enteritidis （S. enteritidis） in paraffin slices and antigen location in infected duck tissues. METHODS： The rabbits were immunized with purified bacillus to obtain S. enteritidis-specific...AIM： To detect Salmonella enteritidis （S. enteritidis） in paraffin slices and antigen location in infected duck tissues. METHODS： The rabbits were immunized with purified bacillus to obtain S. enteritidis-specific antibody, which were then extracted by the caprylic-ammonium sulphate method, purified through High-Q columns. An indirect immuno-fluorescent staining method （IFA） was established to detect the S. enteritidis antigen in paraffin slices. Detected S. enteritidis in each organ tissue of ducklings experimentally infected with S. enteritidis. RESULTS： The gland of Garder, heart, kidney, spleen, liver, brain, ileum, jejunum, bursa of Fabricius from S. enteritidis experimentally infected ducklings were positive or strongly positive, and the S. enteritidis antigen mainly distributed in the infected cell cytoplasm.CONCLUSION： IFA is an intuitionist, sensitive and specific method in detecting S. enteritidis antigen in paraffin wax slices, and it is a good method in diagnosis and antigen location of S. enteritidis. We also conclude that the gland of Garder, heart, kidney, spleen, liver, ileum, jejunum are target organs in S. enteritidis infections of duck, and S. enteritidis is an intracellular parasitic bacterium.展开更多
To evaluate and improve the milk quality in dual purpose cattle with hand or machine milking, a good management and sanitary program was implemented （GMSP） in 40 farms. Was obtained a diagnostic by an interview and ...To evaluate and improve the milk quality in dual purpose cattle with hand or machine milking, a good management and sanitary program was implemented （GMSP） in 40 farms. Was obtained a diagnostic by an interview and in situ evaluation of management conditions and milk samples for laboratory analysis integrating the platform and microbiological counts, before and after of GMSP. The changes achieved were no significant （P 〉 0.05） for pH and density, but alcohol and foreign material were positive modified （P 〈 0.05） by GMSP in both hand and machine milking. The quantities of sediments were decreased （P 〈 0.05） in more than 50.0%. Decrease （P 〈 0.05） was observed in the counts of CFU mL1 （colony forming unitsl） in aerobic mesophilic, coliforms, Salmonella ssp. and Staphylococcus aureus with the GMSP. After GMSP Salmonella ssp. incidence was affected （P 〈 0.05） by hand （55.5%） vs. machine （61.5%） milking type; coliforms count and positive incidence in milk were affected （P 〈 0.05） in hand （81.5%） vs. machine （53.9%）. Therefore it was confirmed that the implementation of adequate sanitary and management practices, in both hand and machine milking, decreased the presence and incidence of microorganisms in milk with potential to produce disease in animals and humans.展开更多
A bacterial cell surface display technique based on an ice nucleation protein has been employed for the development of live vaccine against viral infection. Due to its ubiquitous ability to invade host cells, Salmonel...A bacterial cell surface display technique based on an ice nucleation protein has been employed for the development of live vaccine against viral infection. Due to its ubiquitous ability to invade host cells, Salmonella typhimurium might be a good candidate for displaying viral antigens. We demonstrated the surface display of domain III of Japanese encephalitis virus E protein and the enhanced green fluorescent protein on S. typhimurium BRD509 using the ice nucleation protein. The effects of the motif in the ice nucleation protein on the effective display of integral protein were also investigated. The results showed that display motifs in the protein can target integral foreign protein on the surface of S. typhimurium BRD509. Moreover, recombinant strains with surface displayed viral proteins retained their invasiveness, suggesting that the recombinant S. typhimurium can be used as live vaccine vector for eliciting complete immunogenicity. The data may yield better understanding of the mechanism by which ice nucleation protein displays foreign proteins in the Salmonella strain.展开更多
A cross-sectional study was conducted from November 2008 to May 2009 to estimate the prevalence of Salmonella in retail meat shops in Kathmandu. The methods followed were ISO 18593：2004 for swab sample collection, IS...A cross-sectional study was conducted from November 2008 to May 2009 to estimate the prevalence of Salmonella in retail meat shops in Kathmandu. The methods followed were ISO 18593：2004 for swab sample collection, ISO 6579：2002 for Salmonella isolation and manufacturer＇s instructions （SIFIN, Germany） for serotype identification. A questionnaire was used to collect information on some of the risk factors of shops likely to be associated with Salmonella identification. A total of 492 environmental swab samples （164 chopping board samples, 164 knife samples and 164 table samples） from 82 retail meat shops were analyzed. The prevalence of Salmonella positive shops was 40.2% （95% CI： 29-51）. The isolation rates of Salmonella from chopping boards （36.0%）, knives （32.9%） and tables （25.0%） were not significantly different （P 〉 0.05）. Retail meat shops were 1.9 times more likely to yield Salmonella in the evening （38.2%） as compared to the morning （24.4%） （P = 0.001）. S. Typhimurium （54.5%） was the most common serotype found in retail meat shops followed by S. Enteritidis （16.9%）, S. Haifa （13.6%）, S. Virchow （10.4%）, S. Agona （3.9%） and S. enterica （0.6%）. Among the risk factors examined, ＂hygiene status of shop＂, ＂type of shops＂, ＂number of person handling meats＂, ＂number of knives used＂, ＂number of kinds of meat sold＂ and ＂number of kinds of meat sold using different numbers of knives＂ were individually significantly （P 〈 0.05） associated with Salmonella contamination in the retail meat shops. After univariate analysis of these risk factors, a final logistic regression model with Salmonella yes or no category of shops as outcome variable identified four significant predictors. Odds ratios, indicating the likelihood increase of a shop to achieve Salmonella positivity status were 10.17 for multiple persons rather than a single person involved, 7.66 for open rather than closed shops, 9.44 for use of several knives rather than one knife and 5.18 for single kind of meat using several knives. The results of this investigation revealed that retail meat shops to a noticeable extent are Salmonella contaminated, with a considerable degree of cross-contamination between meats and personnel and equipment used during a day in processing of meats.展开更多
基金the National Key Technology R&D Program of China, No. 2004BA 901A 03National Scientific and Sechnical Support Program, No. 2007Z06-017+3 种基金The Cultvation Fund of the Key Scientific and Technical Innovation Project & Ministry of Education of China, No. 706050Program for New Century Excellent Talents in University, No. NCET-04-0906/NCET-06-0818Sichuan Province Basic Research Program, No. 04JY0290061/07JY029-017Program for Key Disciplines Construction of Sichuan Province No. SZD0418
文摘AIM： To detect Salmonella enteritidis （S. enteritidis） in paraffin slices and antigen location in infected duck tissues. METHODS： The rabbits were immunized with purified bacillus to obtain S. enteritidis-specific antibody, which were then extracted by the caprylic-ammonium sulphate method, purified through High-Q columns. An indirect immuno-fluorescent staining method （IFA） was established to detect the S. enteritidis antigen in paraffin slices. Detected S. enteritidis in each organ tissue of ducklings experimentally infected with S. enteritidis. RESULTS： The gland of Garder, heart, kidney, spleen, liver, brain, ileum, jejunum, bursa of Fabricius from S. enteritidis experimentally infected ducklings were positive or strongly positive, and the S. enteritidis antigen mainly distributed in the infected cell cytoplasm.CONCLUSION： IFA is an intuitionist, sensitive and specific method in detecting S. enteritidis antigen in paraffin wax slices, and it is a good method in diagnosis and antigen location of S. enteritidis. We also conclude that the gland of Garder, heart, kidney, spleen, liver, ileum, jejunum are target organs in S. enteritidis infections of duck, and S. enteritidis is an intracellular parasitic bacterium.
文摘To evaluate and improve the milk quality in dual purpose cattle with hand or machine milking, a good management and sanitary program was implemented （GMSP） in 40 farms. Was obtained a diagnostic by an interview and in situ evaluation of management conditions and milk samples for laboratory analysis integrating the platform and microbiological counts, before and after of GMSP. The changes achieved were no significant （P 〉 0.05） for pH and density, but alcohol and foreign material were positive modified （P 〈 0.05） by GMSP in both hand and machine milking. The quantities of sediments were decreased （P 〈 0.05） in more than 50.0%. Decrease （P 〈 0.05） was observed in the counts of CFU mL1 （colony forming unitsl） in aerobic mesophilic, coliforms, Salmonella ssp. and Staphylococcus aureus with the GMSP. After GMSP Salmonella ssp. incidence was affected （P 〈 0.05） by hand （55.5%） vs. machine （61.5%） milking type; coliforms count and positive incidence in milk were affected （P 〈 0.05） in hand （81.5%） vs. machine （53.9%）. Therefore it was confirmed that the implementation of adequate sanitary and management practices, in both hand and machine milking, decreased the presence and incidence of microorganisms in milk with potential to produce disease in animals and humans.
基金The Knowledge Innovation Program Key Project (KSCX1-YW-R-07)
文摘A bacterial cell surface display technique based on an ice nucleation protein has been employed for the development of live vaccine against viral infection. Due to its ubiquitous ability to invade host cells, Salmonella typhimurium might be a good candidate for displaying viral antigens. We demonstrated the surface display of domain III of Japanese encephalitis virus E protein and the enhanced green fluorescent protein on S. typhimurium BRD509 using the ice nucleation protein. The effects of the motif in the ice nucleation protein on the effective display of integral protein were also investigated. The results showed that display motifs in the protein can target integral foreign protein on the surface of S. typhimurium BRD509. Moreover, recombinant strains with surface displayed viral proteins retained their invasiveness, suggesting that the recombinant S. typhimurium can be used as live vaccine vector for eliciting complete immunogenicity. The data may yield better understanding of the mechanism by which ice nucleation protein displays foreign proteins in the Salmonella strain.
文摘A cross-sectional study was conducted from November 2008 to May 2009 to estimate the prevalence of Salmonella in retail meat shops in Kathmandu. The methods followed were ISO 18593：2004 for swab sample collection, ISO 6579：2002 for Salmonella isolation and manufacturer＇s instructions （SIFIN, Germany） for serotype identification. A questionnaire was used to collect information on some of the risk factors of shops likely to be associated with Salmonella identification. A total of 492 environmental swab samples （164 chopping board samples, 164 knife samples and 164 table samples） from 82 retail meat shops were analyzed. The prevalence of Salmonella positive shops was 40.2% （95% CI： 29-51）. The isolation rates of Salmonella from chopping boards （36.0%）, knives （32.9%） and tables （25.0%） were not significantly different （P 〉 0.05）. Retail meat shops were 1.9 times more likely to yield Salmonella in the evening （38.2%） as compared to the morning （24.4%） （P = 0.001）. S. Typhimurium （54.5%） was the most common serotype found in retail meat shops followed by S. Enteritidis （16.9%）, S. Haifa （13.6%）, S. Virchow （10.4%）, S. Agona （3.9%） and S. enterica （0.6%）. Among the risk factors examined, ＂hygiene status of shop＂, ＂type of shops＂, ＂number of person handling meats＂, ＂number of knives used＂, ＂number of kinds of meat sold＂ and ＂number of kinds of meat sold using different numbers of knives＂ were individually significantly （P 〈 0.05） associated with Salmonella contamination in the retail meat shops. After univariate analysis of these risk factors, a final logistic regression model with Salmonella yes or no category of shops as outcome variable identified four significant predictors. Odds ratios, indicating the likelihood increase of a shop to achieve Salmonella positivity status were 10.17 for multiple persons rather than a single person involved, 7.66 for open rather than closed shops, 9.44 for use of several knives rather than one knife and 5.18 for single kind of meat using several knives. The results of this investigation revealed that retail meat shops to a noticeable extent are Salmonella contaminated, with a considerable degree of cross-contamination between meats and personnel and equipment used during a day in processing of meats.
