The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform
J G Bell - One of the best experts on this subject based on the ideXlab platform.
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village chickens as a reservoir of Salmonella pullorum and Salmonella gallinarum in morocco
Preventive Veterinary Medicine, 1992Co-Authors: Karim Bouzoubaa, K Lemainguer, J G BellAbstract:Abstract Village chicken flocks in two different regions of Morocco were studied for the presence of the causative organisms of pullorum disease and fowl thpoid. Serum samples and cloacal swabs were taken from 250 chickens in 50 farms in each region, and litter samples were taken from each farm. The overall seropositivity was 6%, 23.5% and 58% using the seroagglutination test with Salmonella pullorum antigen, and the microagglutination test and ELISA with Salmonella gallinarum antigen, respectively. Four isolates of S. gallinarum and four isolates of S. pullorum were made. The results show that village chickens can act as a reservoir for these bacteria, and thus any prophylactic campaign must take them into account.
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village chickens as a reservoir of Salmonella pullorum and Salmonella gallinarum in morocco
Preventive Veterinary Medicine, 1992Co-Authors: Karim Bouzoubaa, K Lemainguer, J G BellAbstract:Abstract Village chicken flocks in two different regions of Morocco were studied for the presence of the causative organisms of pullorum disease and fowl thpoid. Serum samples and cloacal swabs were taken from 250 chickens in 50 farms in each region, and litter samples were taken from each farm. The overall seropositivity was 6%, 23.5% and 58% using the seroagglutination test with Salmonella pullorum antigen, and the microagglutination test and ELISA with Salmonella gallinarum antigen, respectively. Four isolates of S. gallinarum and four isolates of S. pullorum were made. The results show that village chickens can act as a reservoir for these bacteria, and thus any prophylactic campaign must take them into account.
Xinan Jiao - One of the best experts on this subject based on the ideXlab platform.
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The SseL protein inhibits the intracellular NF-κB pathway to enhance the virulence of Salmonella pullorum in a chicken model.
Microbial pathogenesis, 2019Co-Authors: Shizhong Geng, Zhiming Pan, Ying Xue, Yaonan Wang, Huqiang Wang, Yuan Cai, Jian Zhang, Paul A. Barrow, Xinan JiaoAbstract:To persist in the host, Salmonella is known to facultatively parasitize cells to escape the immune response. Intracellular Salmonella enterica can replicate using effector proteins translocated across the Salmonella-containing vacuolar membrane via a type III secretion system (T3SS) encoded by Salmonella pathogenicity island-2 (SPI-2). One of these factors, Salmonella secreted factor L (SseL), is a deubiquitinase that contributes to the virulence of Salmonella Typhimurium in mice by inhibiting the cellular NF-κB inflammatory pathway. However, the nature of its effect on the NF-κB pathway is controversial, and little research has been performed in other animal models. In this study, the SseL of Salmonella pullorum was studied, and chickens were used as an infection model. An sseL gene deletion strain, a complementation strain and a eukaryotic expression plasmid were used to clarify the means by which SseL regulates Salmonella virulence and the cellular inflammatory response. SseL significantly enhanced the virulence of Salmonella pullorum in chickens and suppressed activation of the cellular NF-κB pathway, thus inhibiting cellular inflammatory cytokine expression.
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Induction of arthritis in chickens by infection with novel virulent Salmonella pullorum strains.
Veterinary microbiology, 2018Co-Authors: Rongxian Guo, Xiaohui Zhou, Cuiying Huang, Shizhong Geng, Xiang Chen, Zhiming Pan, Xinan JiaoAbstract:Salmonella enterica subsp. enterica serovar Gallinarum biovar pullorum (Salmonella pullorum) is a host-specific serovar causing systemic infection with high mortality in young chicks. pullorum disease is characterized by white diarrhea. However, arthritis has become increasingly frequent recently, particularly in southern China. The aim of the present study was to determine the pathogenesis and arthritis induction of new Salmonella pullorum isolates. We isolated and identified five Salmonella pullorum strains from broilers with bacterial arthritis and lameness in a commercial poultry farm. Four of five isolates were resistant to at least three classes of antibiotics and were defined as multidrug-resistant Salmonella pullorum. All isolates had the same CRISPR sequence type and belonged to a single major cluster. The isolates exhibited high capability of biofilm formation, which may facilitate their dispersal and survival in hostile habitats, and showed high virulence based on embryo lethality and inoculation of newly hatched chicks. Tissue distribution analysis confirmed that SP1621 was more adapted to colonize the joint when compared to the white diarrhoea-causing Salmonella pullorum reference strain S06004. Reproducible arthritis and typical joint lesions were observed in SP1621-infected chicks, and histopathological examination showed necrotic synovitis and cartilage tissue hyperplasia of the joint. Koch's postulates were confirmed when the novel Salmonella pullorum strain was re-isolated from the joint tissues of experimentally inoculated chicks. These novel Salmonella pullorum isolates have unique ability to induce arthritis in chickens, representing expanded pathogenic diversity in China. These results suggest the need for strict control strategies and new vaccines to prevent the disease.
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O-polysaccharide is important for Salmonella pullorum survival in egg albumen, and virulence and colonization in chicken embryos.
Avian Pathology, 2017Co-Authors: Rongxian Guo, Shizhong Geng, Xiang Chen, Zhiming Pan, Yang Jiao, Xinan JiaoAbstract:The pathogen Salmonella pullorum is the causative agent of persistent systemic infection of poultry, leading to economic losses in developing countries due to morbidity, mortality and reduction in egg production. These infections may result in vertical transmission to eggs or progeny. Limited information is available regarding the mechanisms involved in the survival of Salmonella pullorum in egg albumen and developing chicken embryos. Hence, we investigated the role of O-polysaccharide in the contamination of eggs and the colonization of chicken embryos. Compared with the wild-type strain, the isogenic waaL mutant exhibited an O-antigen-deficient rough phenotype, and increased sensitivity to egg albumen and chicken serum, as well as reduced adherence to DF-1 cells. Infection with Salmonella pullorum lacking O-polysaccharide resulted in significantly reduced embryo lethality and bacterial colonization. These results suggest that O-polysaccharide is essential for Salmonella pullorum colonization in eggs, both post-lay and developing embryos. The chicken embryo infection model could be used to characterize the interaction between Salmonella pullorum and developing embryos, and it will also contribute to the development of more rational vaccines to protect laying hens and embryos.
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Safety, Protective Immunity, and DIVA Capability of a Rough Mutant Salmonella pullorum Vaccine Candidate in Broilers
Frontiers in microbiology, 2017Co-Authors: Rongxian Guo, Shizhong Geng, Xiang Chen, Zhiming Pan, Yang Jiao, Shanshan Zhu, Xiao Fei, Xinan JiaoAbstract:Salmonella enterica subsp. enterica serovar Gallinarum biovar pullorum (Salmonella pullorum) is highly adapted to chickens causing an acute systemic disease that results in high mortality. Vaccination represents one approach for promoting animal health, food safety and reducing environmental persistence in Salmonella control. An important consideration is that Salmonella vaccination in poultry should not interfere with the salmonellosis monitoring program. This is the basis of the DIVA (Differentiation of Infected and Vaccinated Animals) program. In order to achieve this goal, waaL mutant was developed on a spiC mutant that was developed previously. The safety, efficacy, and DIVA features of this vaccine candidate (Salmonella pullorum ΔspiCΔwaaL) were evaluated in broilers. Our results show that the truncated LPS in the vaccine strain has a differentiating use as both a bacteriological marker (rough phenotype) and also as a serological marker facilitating the differentiation between infected and vaccinated chickens. The rough mutant showed adequate safety being avirulent in the host chicks and showed increased sensitivity to environmental stresses. Single intramuscular immunization of day-old broiler chicks with the mutant confers ideal protection against lethal wild type challenge by significantly stimulating both humoral and cellular immune responses as well as reducing the colonization of the challenge strain. Significantly lower mean pathology scores were observed in the vaccination group compared to the control group. Additionally, the mutant strain generated cross-protection against challenge with the wild type Salmonella Gallinarum thereby improving survival and with the wild type Salmonella Enteritidis thereby reducing colonization. These results suggest that the double-mutant strain may be a safe, effective, and cross-protective vaccine against Salmonella infection in chicks while conforming to the requirements of the DIVA program.
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identification by pcr signature tagged mutagenesis of attenuated Salmonella pullorum mutants and corresponding genes in a chicken embryo model
Microbial Pathogenesis, 2017Co-Authors: Shizhong Geng, Rongxian Guo, Zhiming Pan, Yang Jiao, Yaonan Wang, Paul A. Barrow, Qin Tian, Chao Yin, Haopeng Geng, Xinan JiaoAbstract:A key feature of the fowl-specific pathogen Salmonella pullorum is its vertical transmission to progeny via the egg. In this study, PCR signature-tagged mutagenesis identified nine genes of a strain of S. pullorum that contributed to survival in the chicken embryo during incubation. The genes were involved in invasion, cell division, metabolism and bacterial defence. The competition index in vivo and in vitro together with a virulence evaluation for chicken embryos of all nine mutant strains confirmed their attenuation.
Karim Bouzoubaa - One of the best experts on this subject based on the ideXlab platform.
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village chickens as a reservoir of Salmonella pullorum and Salmonella gallinarum in morocco
Preventive Veterinary Medicine, 1992Co-Authors: Karim Bouzoubaa, K Lemainguer, J G BellAbstract:Abstract Village chicken flocks in two different regions of Morocco were studied for the presence of the causative organisms of pullorum disease and fowl thpoid. Serum samples and cloacal swabs were taken from 250 chickens in 50 farms in each region, and litter samples were taken from each farm. The overall seropositivity was 6%, 23.5% and 58% using the seroagglutination test with Salmonella pullorum antigen, and the microagglutination test and ELISA with Salmonella gallinarum antigen, respectively. Four isolates of S. gallinarum and four isolates of S. pullorum were made. The results show that village chickens can act as a reservoir for these bacteria, and thus any prophylactic campaign must take them into account.
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village chickens as a reservoir of Salmonella pullorum and Salmonella gallinarum in morocco
Preventive Veterinary Medicine, 1992Co-Authors: Karim Bouzoubaa, K Lemainguer, J G BellAbstract:Abstract Village chicken flocks in two different regions of Morocco were studied for the presence of the causative organisms of pullorum disease and fowl thpoid. Serum samples and cloacal swabs were taken from 250 chickens in 50 farms in each region, and litter samples were taken from each farm. The overall seropositivity was 6%, 23.5% and 58% using the seroagglutination test with Salmonella pullorum antigen, and the microagglutination test and ELISA with Salmonella gallinarum antigen, respectively. Four isolates of S. gallinarum and four isolates of S. pullorum were made. The results show that village chickens can act as a reservoir for these bacteria, and thus any prophylactic campaign must take them into account.
Daftar Pustaka - One of the best experts on this subject based on the ideXlab platform.
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Antibacterial Test of Rumbia Root (Metroxylon sagu Rottb.) Decoction Against Bacteria Salmonella pullorum Uji Antibakteri Dekok Akar Rumbia (Metroxylon sagu Rottb.) Terhadap Bakteri Salmonella pullorum
2014Co-Authors: Dosen Fakultas Kedokteran Hewan, Daftar PustakaAbstract:The rumbia root (Metroxylon sagu Rottb.) was known have several active substances such as flavanoids, alkaloids, saponins and tanins, which are potential as antimicrobial agents. The aim of this research is to prove the effectivity of rumbia roots decoction as an antimicrobial against Salmonella pullorum in vitro. Dilution method with four concentrations dan two controls was used in this research to determine Minimum Inhibitory Concentration (MIC) and continued by streaking on Salmonella Shigella Agar (SSA) to determine Minimum Bacteriocide Concentration (MBC). The treatment used were : 100%, 75%, 50%, 25%, control negative and control positive which used antibiotic Ampicilin, each treatment repeted with 4 repetitions respectively. The obtained data showed that the rumbia roots decoction has an antimicrobial effect to Salmonella pullorum with the Minimum Bacteriocide Concentration (MBC) is 50%.
Adinda Anina Apriliyani Hidayat - One of the best experts on this subject based on the ideXlab platform.
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UJI ANTIBAKTERI DEKOK AKAR RUMBIA (Metroxylon sagu Rottb.) TERHADAP BAKTERI Salmonella pullorum
2014Co-Authors: Adinda Anina Apriliyani HidayatAbstract:The rumbia root (Metroxylon sagu Rottb.) was known have several active substances such as flavanoids, alkaloids, saponins and tanins, which are potential as antimicrobial agents. The aim of this research is to prove the effectivity of rumbia roots decoction as an antimicrobial against Salmonella pullorum in vitro. Dilution method with four concentrations dan two controls was used in this research to determine Minimum Inhibitory Concentration (MIC) and continued by streaking on Salmonella Shigella Agar (SSA) to determine Minimum Bacteriocide Concentration (MBC). The treatment used were : 100%, 75%, 50%, 25%, control negative and control positive which used antibiotic Ampicilin, each treatment repeted with 4 repetitions respectively. The obtained data showed that the rumbia roots decoction has an antimicrobial effect to Salmonella pullorum with the Minimum Bacteriocide Concentration (MBC) is 50%.
