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Effects of exogenous iron on Escherichia coli septicemia of turkeys.
1986
Bolin C.A.
Characterisation of Yersinia enterocolitica strains isolated from wildlife in the northwestern Italian Alps 全文
2022
Carella, Emanuele | Romano, Angelo | Domenis, Lorenzo | Robetto, Serena | Spedicato, Raffaella | Guidetti, Cristina | Pitti, Monica | Orusa, Riccardo
Yersiniosis is a zoonosis causing gastroenteritis, diarrhoea, and occasionally reactive arthritis and septicaemia. Cases are often linked to meat consumption and the most common aetiological agent is the Gram-negative bacilliform Yersinia enterocolitica bacterium. The occurrence of Yersinia spp. among wild animals has mostly been studied in wild boar, but it has seldom been in other species. A total of 1,868 faecal samples from animals found dead or hunted were collected between 2015 and 2018 in the Valle d’Aosta region of the northwestern Italian Alps. Alpine ibex faecal samples were collected during a health monitoring program in 2018. Bacteria were isolated via PCR and confirmed as Y. enterocolitica biochemically. Strain antimicrobial susceptibility was tested by Kirby–Bauer disc diffusion, and the presence of virulence factors and antimicrobial resistance genes was investigated using whole-genome sequencing. Yersinia enterocolitica strains of biotype 1A were detected in six faecal samples from red deer (0.93%), roe deer (0.49%) and red foxes (0.7%). Strains found in beech martens (3.57%) and Alpine ibex (2.77%) belonged to biotypes 1B and 5, respectively and harboured the pYPTS01 plasmid that had only been detected in Y. pseudotuberculosis PB1/+. All the isolates were resistant to ampicillin and erythromycin. The biovar 1A strains exhibited different virulence factors and behaved like non-pathogenic commensals. The strain from an Alpine ibex also harboured the self-transmissible pYE854 plasmid that can mobilise itself and the pYPTS01 plasmid to other strains. The beech marten could be considered a sentinel animal for Y. enterocolitica. Phenotypic resistance may account for the ability of all the strains to resist β-lactams.
显示更多 [+] 显示较少 [-]Validation of a disease model in Japanese quail (Coturnix coturnix japonica) with the use of Escherichia coli serogroup O2 isolated from a turkey 全文
2011
Nain, Sukhbir | Smits, Jidit E.G.
This study established a disease model and protocol for bacterial challenge with Escherichia coli serogroup O2 strain EC317 in Japanese quail. Five groups of 10 birds each were injected subcutaneously in the breast with 200 μL of a brain–heart infusion (BHI) culture containing 1 × 10(8), 1 × 10(7), 1 × 10(6), 1 × 10(5), or 1 × 10(4) colony-forming units/mL of the test organism, which had been isolated from a turkey with cellulitis and septicemia. Birds in a 6th group were controls that received sterile BHI alone. Localized lesions of cellulitis developed in all of the birds that received E. coli. The morbidity and mortality rates were highest (100%) in the birds receiving the highest dose of E. coli and decreased linearly with decreasing dose (P < 0.05). Severity of disease, including lesions of pericarditis and perihepatitis, was also directly proportional to the dose of E. coli. These findings indicate that this disease challenge protocol can be used to study disease resistance and immunologic consequences of contaminant exposure or other stressors in birds.
显示更多 [+] 显示较少 [-]Concentrations of amino acids in the plasma of neonatal foals with septicemia
1991
Zicker, S.C. | Spensley, M.S. | Rogers, Q.R. | Willits, N.H.
Concentrations of amino acids in the plasma of 13 neonatal foals with septicemia were compared with the concentrations of amino acids in the plasma of 13 age-matched neonatal foals without septicemia. Analysis of the results revealed significantly lower concentrations of arginine, citrulline, isoleucine, proline, threonine, and valine in the plasma of foals with septicemia. The ratio of the plasma concentrations of the branched chain amino acids (isoleucine, leucine, and valine) to the aromatic amino acids (phenylalanine and tyrosine), was also significantly lower in the foals with septicemia. In addition, the concentrations of alanine, glycine, and phenylalanine were significantly higher in the plasma of foals with septicemia. Therefore, neonatal foals with septicemia had significant differences in the concentrations of several amino acids in their plasma, compared with concentrations from healthy foals. These differences were compatible with protein calorie inadequacy and may be related to an alteration in the intake, production, use, or clearance of amino acids from the plasma pool in sepsis.
显示更多 [+] 显示较少 [-]Role of the capsular polysaccharide as a virulence factor for Streptococcus suis serotype 14 全文
2015
Roy, David | Auger, Jean-Philippe | Segura, Mariela | Fittipaldi, Nahuel | Takamatsu, Daisuke | Okura, Masatoshi | Gottschalk, Marcelo
Streptococcus suis is an important swine pathogen and a zoonotic agent causing meningitis and septicemia. Although serotype 2 is the most virulent type, serotype 14 is emerging, and understanding of its pathogenesis is limited. To study the role of the capsular polysaccharide (CPS) of serotype 14 as a virulence factor, we constructed knockout mutants devoid of either cps14B, a highly conserved regulatory gene, or neu14C, a gene coding for uridine diphospho-N-acetylglucosamine 2-epimerase, which is involved in sialic acid synthesis. The mutants showed total loss of the CPS with coagglutination assays and electron microscopy. Phagocytosis assays showed high susceptibility of mutant Δcps14B. An in vivo murine model was used to demonstrate attenuated virulence of this non-encapsulated mutant. Despite the difference in the CPS composition of different serotypes, this study has demonstrated for the first time that the CPS of a serotype other than 2 is also an important antiphagocytic factor and a critical virulence factor.
显示更多 [+] 显示较少 [-]Antimicrobial activity of bovine bactericidal permeability-increasing protein-derived peptides against gram-negative bacteria isolated from the milk of cows with clinical mastitis 全文
2007
Chockalingam, A. | Zarlenga, D.S. | Bannerman, D.D.
Objective--To evaluate antimicrobial activity of bovine bactericidal permeability-increasing protein (bBPI)-derived synthetic peptides against mastitis-causing gram-negative bacteria. Sample Population--Bacterial isolates from the milk of cows with clinical mastitis. Procedures--3 peptides were synthesized with sequences corresponding to amino acids 65 to 99 (bBPI6599) or 142 to 169 (bBPI142169) or the combination of amino acids 90 to 99 and 148 to 161 (bBPI9099,148161) of bBPI. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of these peptides against bacterial isolates from cows with mastitis were determined by use of a standardized broth microdilution assay. The ability of these peptides to retain their antimicrobial activity in serum and milk was also evaluated. Finally, bacterial lipopolysaccharide (LPS)-neutralizing activity of these peptides was assayed with the Limulus amebocyte lysate test. Results--Of the 3 peptides tested, bBPI9099,148161 had the widest spectrum of antimicrobial activity, with MIC and MBC values ranging from 16 to 64 Mg/mL against Escherichia coli, Klebsiella pneumoniae, and Enterobacter spp and from 64 to 128 Mg/mL against Pseudomonas aeruginosa. None of the peptides had any growth-inhibitory effect on Serratia marcescens. The antimicrobial activity of bBPI9099,148161 was inhibited in milk, but preserved in serum. Finally, bBPI142169 and bBPI9099,148161 completely neutralized LPS. Conclusions and Clinical Relevance--bBPI9099,148161 is a potent neutralizer of the highly proinflammatory molecule bacterial LPS and has antimicrobial activity against a variety of gram-negative bacteria. The ability of bBPI9099,148161 to retain antimicrobial activity in serum suggests a potential therapeutic application for this peptide in the management of gram-negative septicemia.
显示更多 [+] 显示较少 [-]Septicemic colibacillosis accompanied by white-spotted kidney in a calf
2005
Yoon, S.S. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), E-mail: yoonss24@hotmail.com | Han, H.R. (Seoul National University, Seoul, Republic of Korea) | Bae, Y.C. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Lee, H.S. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Yang, D.K. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Kwon, Y.K. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea)
We report septicemic colibacillosis accompanied by white-spotted kidney in a 30-day old female Holstein-Friesian dairy calf. Grossly, there were numerous white spots sized average 0.5cm in diameter in both kidneys. When sectioned sagittally, there were radially oriented gray streaks extending outward and reaching the renal cortex. The renal papillae were ulcerated, white to gray in color and very friable. Histologically, there was extensive purulent inflammation characterized by severe neutrophilic cellular infiltrations in the tubular lumens and interstitia. In addition, massive coagulative necrosis were found in the apices of papillae.
显示更多 [+] 显示较少 [-]Salmonella enterica serotype Choleraesuis infection in weaned pigs: a first clinicopathological case report from Korea 全文
2022
Kim, J.H. | Kim, G.Y. | Lee, H.K. | Moon, B.Y. | Lee, K.C. | Byun, J.W. | Park, J.Y. | Lee, K.K. | Jeoung, H.Y. | Ko, M.K. | Ku, B.K. | Chung, Y.S. | Bae, Y.C.
Salmonella enterica serotype Choleraesuis causes swine paratyphoid, with clinical findings of enterocolitis and septicemia. However, the clinicopathological features of S. Choleraesuis infections in pigs have not been reported in Korea. We describe the pathological findings of two weaned pigs with S. Choleraesuis infections, presenting with diarrhea, cough, and sudden death. Pathological examination indicated severe necrotic colitis in pig 1 and septicemic lesions in pig 2. Multidrug-resistant S. Choleraesuis was isolated from the pigs’ lungs and intestinal contents. Further research is required for the surveillance of S. Choleraesuis infections in pigs and the virulence estimation in the S. Choleraesuis isolates.
显示更多 [+] 显示较少 [-]A case of septicaemic pasteurellosis in captive sambar deer, cervus unicolor 全文
2018
Wan Norulhuda W. A. W. | Norhartini I. | Tariq J.
Septicaemic pasteurellosis is a fatal, sometimes epidemic, bacterial disease of domestic and wild animals including deer, bison, elk, and pronghorn antelope caused by Pasteurella multocida. This is the case report of septicaemic pasteurellosisin a captive sambar deer. The carcass was sent from Royal Endurance Stable, Bachok, Kelantan to the Kota Bharu RegionalVeterinary Laboratory for post-mortem. Gross examination of organs was followed by collection of specimens from lung, kidney,liver, spleen and heart for histopathology and bacterial examination. Pooled organ samples with rumen content were collected and sent to the nearest Chemistry Department for investigation. For histology, the liver, lung, spleen, kidney, and heart specimens were fixed in 10% neutral formalin, and routinely embedded in paraffin. Fivemicrometer sections were stained with H&E. Other tests such as worm and ectoparasiteidentification were conducted to identify the parasites. Post-mortem lesions revealed generalised haemorrhage in the organs.Pasteurella multocida serogroup B and E. coli were isolated from multiple tissues of the animal. Histological examination alsorevealed severe congestion and haemorhage of multiple tissues with infiltration of the inflammatory cells. The most likely mode of transmission of these bacteria is through an infected wound and into the bloodstream, thereby causing severe septicemia and death to the animal.
显示更多 [+] 显示较少 [-]Development of loop-mediated isothermal amplification–based diagnostic assays for detection of Pasteurella multocida and hemorrhagic septicemia–associated P multocida serotype B:2 全文
2017
Moustafa, Ahmed M. | Benneett, Mark D.
OBJECTIVE To develop 2 rapid loop-mediated isothermal amplification (LAMP) assays for detection of Pasteurella multocida DNA (Pm-LAMP assay) and P multocida DNA from strains associated with hemorrhagic septicemia (HS) in cattle and buffalo (HS-LAMP assay). SAMPLE Solutions containing 16 P multocida strains and 9 other bacterial species at various concentrations. PROCEDURES Optimal conditions were determined for running the Pm-LAMP and HS-LAMP assays. The assays were then used to detect DNA of the test organisms. Results of LAMP assays were validated against conventional PCR assays designed for specific detection of P multocida and the B:2 serotype of HS-associated strains. RESULTS Following incubation of sample reaction mixtures for 27 minutes, specificity and sensitivity of the HS-LAMP assay at template DNA amounts as low as 5 pg were 93% and 97%, respectively. When duplicates of each sample were incubated for 28 minutes (a positive result defined as positive results for both reactions of a given sample), specificity and sensitivity of the HS-LAMP assay in the same conditions increased to 100%. The best specificity and sensitivity of Pm-LAMP single (93% and 91%) and duplicate (97% and 98%) reactions at template DNA amounts as low as 10 pg were achieved at 33 and 34 minutes, respectively. CONCLUSIONS AND CLINICAL RELEVANCE These preliminary findings suggested the developed HS-LAMP assay had high sensitivity and specificity for detection of HS-associated P multocida. Additional research is needed to determine the accuracy of the assay for use on clinical specimens obtained in HS-endemic countries such as Pakistan and Thailand.
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