colistin and Salmonella-Infections--Animal

Bacteriophages (BP) are viruses that can infect bacteria. The present study evaluated the effect of BP on Salmonella infected broilers. A number of 150 day-old broilers were used in a completely randomized design with five treatments that included: (1) basal diet from day 0 to 28; (2) basal diet + 0.3 g/kg of colistin from day 0 to 28; (3) basal diet from day 1 to 13, and basal diet + 0.4 g/kg of colistin from day 14 to 28; (4) basal diet + 1 g/kg of BP from day 0 to 28; (5) basal diet + 1.5 g/kg of BP from day 0 to 28. On day 13, 15 chickens from each treatment were challenged by Salmonella Enteritidis (SE), while fifteen from each treatment were not; instead, they were kept in the same cage with the challenged chickens (exposed chickens). At 7 and 14 days post-challenge, the number of SE and coliform bacteria in the cecum and liver of colistin and BP-fed birds was lower than the control treatment. In exposed and challenged chickens, the height and surface area of villus were greater in the BP and colistin-supplemented groups. Serum concentrations of aspartate aminotransferase and alanine transaminase were greater, while serum albumin and triglycerides concentrations were lower in the control treatment. The liver of the challenged chickens had more pathological lesions than exposed birds. BP significantly decreased PPARγ gene expression in exposed chickens. In the challenged and exposed chickens, TLR4 gene expression was lower in BP and colistin-treated birds as compared to the control. In conclusion, adding BP to the diet from the day of age prevents the spread of Salmonella.

Topics: Animal Feed; Animals; Bacteriophages; Chickens; Colistin; Diet; Dietary Supplements; Poultry Diseases; Salmonella enteritidis; Salmonella Infections, Animal

Phage therapy is a promising alternative treatment of bacterial infections in human and animals. Nevertheless, despite the appearance of many bacterial strains resistant to antibiotics, these drugs still remain important therapeutics used in human and veterinary medicine. Although experimental phage therapy of infections caused by

Topics: Animals; Anti-Bacterial Agents; Bacteriophages; Chickens; Colistin; Enrofloxacin; Phage Therapy; Salmonella enterica; Salmonella Infections, Animal; Salmonella typhimurium; Serogroup

Salmonella is a zoonotic bacterium transmitted through the food chain and is an important cause of disease in humans. The current study is aimed to characterize Salmonella isolates from broiler breeder chickens farms using, polymerase chain reaction (PCR) and sequencing analysis of representative isolates.. S. Kentucky (n=11), S. Enteritidis (n=4), S. Typhimurium (n=3), S. Breanderp (n=1), and Sand S. Newport (n=1), were identified from chicken farms. Antimicrobial sensitivity test among the strains were investigated using 13 antibacterial discs. The amplified fragments of fliC and sefA genes were used to characterize S. Kentucky, S. Enteritidis and S. Typhimurium strains. Sequence analysis of the amplified PCR products for Salmonella Kentucky, Enteritidis and Typhimurium were carried out.. Antimicrobial sensitivity testing revealed that 95% of the isolates were resistant to penicillin, 85% to norfloxacin and colistin sulfate (each), 75% to gentamicin, 70% to nalidixic acid and 60% to flumequine. The obtained sequences revealed the close identity of the isolated strains with other Salmonella reference strains in different countries.. Analysis of the selected salmonellae confirm the report of Salmonella Enteritidis, Salmonella Typhimurium and Salmonella Kentucky circulation among broiler breeder flocks and the need to determine antibacterial susceptibility pattern regularly to detect multidrug-resistant salmonellae. The present study reports the circulation of Salmonella Kentucky, Enteritidis and Typhimurium among broiler breeder farms in Egypt. Emergency control of salmonellae is a global public health concern.

Topics: Animals; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Chickens; Colistin; Fluoroquinolones; Genetic Variation; Gentamicins; Humans; Nalidixic Acid; Norfloxacin; Penicillins; Phylogeny; Polymerase Chain Reaction; Poultry Diseases; Salmonella enterica; Salmonella Infections, Animal; Sequence Alignment; Sequence Analysis, DNA; Zoonoses

Topics: Animals; Bacteremia; Colistin; Humans; Salmonella; Salmonella enterica; Salmonella Infections, Animal

Salmonella serovars are leading causes of gastrointestinal disease and have become increasingly resistant to fluoroquinolone and cephalosporin antibiotics. Overcoming this healthcare crisis requires new approaches in antibiotic discovery and the identification of unique bacterial targets. In this work, we describe a chemical genomics approach to identify inhibitors of Salmonella virulence. From a cell-based, promoter reporter screen of ∼50,000 small molecules, we identified dephostatin as a non-antibiotic compound that inhibits intracellular virulence factors and polymyxin resistance genes. Dephostatin disrupts signaling through both the SsrA-SsrB and PmrB-PmrA two-component regulatory systems and restores sensitivity to the last-resort antibiotic, colistin. Cell-based experiments and mouse models of infection demonstrate that dephostatin attenuates Salmonella virulence in vitro and in vivo, suggesting that perturbing regulatory networks is a promising strategy for the development of anti-infectives.

Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Colistin; Drug Synergism; Female; Histidine Kinase; Hydroquinones; Mice; Mice, Inbred C57BL; Polymyxin B; Salmonella; Salmonella Infections, Animal; Small Molecule Libraries; Survival Rate; Transcription Factors; Virulence

We evaluate here the presence of the mcr-1-like and mcr-2 genes in Escherichia coli and Salmonella spp. isolated from healthy food-producing animals at slaughter between 2002 and 2014 in Europe. Isolates were retrieved from cattle, pig and chicken from 11 European countries of production. The susceptibility to colistin and antibiotics used in human medicine was determined by agar dilution. Colistin-resistant isolates were PCR-screened for mcr genes. mcr-positive isolates were typed by Pulsed-Field Gel Electrophoresis (PFGE) and Multi-Locus Sequence Typing. Among the 10,206 E. coli and 1774 Salmonella spp. isolated from cattle, pigs and chickens, 148 E. coli and 92 Salmonella spp. isolates were resistant to colistin. We found mcr-1-like gene in 68 (0.7%) E. coli and 2 (0.1%) Salmonella isolates whereas none of the isolates tested positive for mcr-2. MCR-1-like-positive E. coli were isolated from 2008 to 2014 in chicken (n=44, 1.2%) and pigs (n=24, 0.7%). The presence of mcr-1-like varied from 0 to 4.0% depending on the year and the animal species. mcr-1-like-positive isolates came from animals originating from Germany (n=38), Spain (n=23), The Netherlands (n=5), and France (n=4). They were distributed in 63 different PFGE types and 37 different STs, with ST10 being the most prevalent. The two mcr-1-like-positive Salmonella spp. were isolated from France and Germany from a pig and a chicken, respectively. mcr-1-like gene is present in food-producing animals at slaughter in European countries with the highest occurrence in chickens. The high clonal diversity of E. coli underlines the evidence for horizontal transfer of mcr-1-like genes.

Topics: Abattoirs; Animals; Anti-Bacterial Agents; Bacterial Proteins; Bacterial Typing Techniques; Cattle; Chickens; Colistin; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Escherichia coli; Escherichia coli Infections; Escherichia coli Proteins; Europe; Multilocus Sequence Typing; Salmonella; Salmonella Infections, Animal; Swine

A novel mcr colistin resistance gene was identified in a strain of Salmonella enterica, monophasic variant of serovar Typhimurium (4,5,12:i:- ), isolated from a pig at slaughter in Italy in 2013, and in Escherichia coli strains collected during routine diagnostic of post-weaning diarrhoea in pigs from Spain and Belgium in 2015 and 2016. Immediate implementation of mcr-screening including this novel gene variant is required for Salmonella and E. coli from humans and food-producing animals in Europe.

Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Belgium; Colistin; Drug Resistance, Bacterial; Escherichia coli; Italy; Plasmids; Salmonella Infections, Animal; Salmonella typhimurium; Spain; Swine; Swine Diseases

Recent findings suggest that use of colistin as a last resort antibiotic is seriously threatened by the rise of a new plasmid mediated mechanism of resistance (MCR-1). This work identifies, for the first time in Southern Europe, the gene mcr-1 in nine strains from farm animals (poultry and swine) corresponding to five Escherichia coli and four Salmonella enterica, among which three belong to serovar Typhimurium and one to Rissen. The MCR-1 was found encoded by a plasmid highly mobilizable by conjugation to the E. coli J53 strain. Two E. coli strains carried two determinants, mcr-1 plus pmrA or pmrB mutations, known to confer colistin resistance.

Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Colistin; Drug Resistance, Bacterial; Escherichia coli; Escherichia coli Infections; Poultry Diseases; Salmonella enterica; Salmonella Infections, Animal; Salmonella typhimurium; Sequence Analysis, DNA; Spain; Swine; Swine Diseases

Since initial identification in China, the widespread geographical occurrence of plasmid-mediated colistin resistance gene mcr-1 in Enterobacteriaceae has been of great concern. In this study, a total of 22 Salmonella enterica were resistant to colistin, while only five isolates which belonged to ST34 Salmonella enterica serovar Typhimurium (S. Typhimurium) were mcr-1 positive. Four of them shared nearly identical PFGE type, although they were from different host species and diverse geographical locations. All the mcr-1-positive S. Typhimurium exhibited multi-resistant phenotypes including ampicillin, streptomycin, gentamicin, florfenicol, nalidixic acid, tetracycline, trimethoprim-sulfamethox, in addition to colistin. The oqxAB and aac(6')-Ib-cr genes were present alone or in combination in four (80.0%) and five (100%) isolates, respectively. The mcr-1 gene was located on a transferable IncI2 plasmid in the four genetically related strains. In the other one strain, mcr-1 was located on an approximately 190 kb IncHI2 plasmid. In conclusion, we report five mcr-1-positive S. Typhimurium/ST34 isolates. Both clonal expansion and horizontal transmission of IncI2-type plasmids were involved in the spread of the mcr-1 gene in Salmonella enterica from food-producing animals in China. There is a great need to monitor the potential dissemination of the mcr-1 gene.

Topics: Animals; Base Sequence; Clone Cells; Colistin; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Genes, Bacterial; Microbial Sensitivity Tests; Molecular Typing; Plasmids; Salmonella Infections, Animal; Salmonella typhimurium

Salmonella enterica serovar Enteritidis is one of the leading causes of food-borne salmonellosis in humans. Poultry is the single largest reservoir, and the consumption of incorrectly processed chicken meat and egg products is the major source of infection. Since 2006, the use of antibiotics as growth promoters has been banned in the European Union, and the dietary inclusion of β-galactomannans (βGM) has become a promising strategy to control and prevent intestinal infections. The aim of this study was to investigate the effect of various βGM-rich products on intestinal morphology in chickens challenged with Salmonella Enteritidis. To assess this effect, a total of 280 male Ross 308 chickens were studied (40 animals per treatment housed in 5 cages). There were 7 treatments, including controls: uninoculated birds fed the basal diet (negative control) and inoculated birds fed the basal diet (positive control) or the basal diet supplemented with Salmosan (1 g/kg), Duraió gum (1 g/kg), Cassia gum (1 g/kg), the cell walls of Saccharomyces cerevisiae (0.5 g/kg), or the antibiotic colistine (0.8 g/kg). The birds were fed these diets from the d 1 to 23, except the animals in the colistine group, which were fed the diet containing the antibiotic only from d 5 to 11. The inoculated animals were orally infected on d 7 with 10(8) cfu of Salmonella Enteritidis. Bird performance per replicate was determined for the whole study period (23 d), and the distal ileum and cecal tonsil of 5 animals per treatment (1 animal per replicate) were observed at different magnification levels (scanning electron, light, and laser confocal microscopy). In the images corresponding to the treatments containing βGM we observed more mucus, an effect that can be associated with the observation of more goblet cells. Moreover, the images also show fewer M cells, which are characteristic of infected animals. Regarding the morphometric parameters, the animals that received Duraió and Cassia gums show greater (P = 0.001 and P = 0.016, respectively) villus length compared with the animals in the positive control, thus indicating the capacity of these products to increase epithelial surface area. However, no effect (P > 0.05) on microvillus dimensions was detected. In conclusion, the results obtained indicating the beneficial effects of these βGM on intestinal morphology give more evidence of the positive effects of these supplements in poultry nutrition.

Topics: Animal Feed; Animals; Anti-Bacterial Agents; Cecum; Chickens; Colistin; Diet; Dietary Supplements; Enteritis; Galactose; Humans; Ileum; Intestinal Mucosa; Intestines; Male; Mannans; Microvilli; Poultry Diseases; Salmonella enteritidis; Salmonella Infections, Animal

The main problem for the local guinea fowl (Numida meleagris) traditional farming and raising system in north-east Benin is the high mortality rate of the keets (up to 70%) due to a combination of climatic, nutritional, hygienic and infectious causes. The present study was carried out to identify and compare the isolates of Salmonella enterica from necropsied keets, laying guinea fowl, surrogate hen mothers, other contact animal species and farmers during four laying seasons (2007 to 2010). S. enterica belonging to eight different serotypes (Adelaide, Farakan, Kingston, Legon, Luke, Oakland, Sangalkam and Teshie) and one untypable isolate were isolated from 13 to 19% of the necropsied keets. The serotypes Adelaide, Farakan, Luke, Sangalkam and Teshie and the untypable isolate were isolated in only one township during 1 year of sampling, while serotypes Oakland, Legon and Kingston were present in two to three townships for 2 to 3 years of sampling. Serotypes Farakan, Kingston, Legon, Oakland and Sangalkam were also isolated from faecal samples of laying guinea fowl and/or surrogate domestic fowl hen mothers. Further comparison by pulsed-field gel electrophoresis and virulotyping provided evidence for their clonality within each of those five serotypes and therefore for the adult guinea fowl and/or hens as the most probable origin of contamination of the keets. The antibiotic resistance profiles, with all isolates resistant to oxacillin, sulfamethoxazol and colistin, emphasize the rise of antibiotic resistance in salmonellas from guinea fowl in this area and the need for alternative therapy policies for these birds.

Topics: Animal Husbandry; Animals; Anti-Bacterial Agents; Bacterial Typing Techniques; Benin; Bird Diseases; Colistin; DNA Primers; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Embryo, Nonmammalian; Feces; Female; Galliformes; Microbial Sensitivity Tests; Ovum; Oxacillin; Polymerase Chain Reaction; Prevalence; Salmonella enterica; Salmonella Infections, Animal; Serotyping; Sulfamethoxazole

Salmonellae are wide spread in man and animals world wide and are of increasing significance as causative agents of foodborne diseases in man. The European Union, national authorities and the pig industry are therefore more and more interested in the Salmonella status of the pig population. The aim of this study was to estimate the bacteriological prevalence of Salmonella in finishing pig herds, the serogroup and the resistance to antibiotics of the isolated Salmonellae and a preliminary risk analysis of factors associated with infection. For this, 317 finishing pig herds were randomly selected from a database containing 1500 herds in the southern part of the Netherlands. In each herd 24 samples of fresh faeces were collected from two compartments with pigs close to market weight. Per compartment 12 samples of faeces were pooled into one pooled sample. Pooled samples were cultured in duplicate. Salmonella spp. were recovered from 71 out of 306 herds (23%) in which two compartments could be sampled. A total of 108 isolated Salmonella's were serotyped: 71 serogroup B, 3 serogroup C1, 6 serogroup C2, 22 serogroup D1, and 6 isolates neither serogroup B, C or D1. Of a total of 115 Salmonella isolates tested, none were resistant to colistin, enrofloxacin, flumequin or gentamicin. Automated liquid feeding of by-products, and membership of an Integrated Quality Control (IQC) production group were associated with a decreased risk of infection, while use of trough feeding was associated with an increased risk of infection. It is necessary to test these presumed risk factors in intervention studies to evaluate their potency to reduce the Salmonella prevalence in finishing pigs and thereby reduce the risk of Salmonellosis in people consuming pork.

Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Cluster Analysis; Colistin; Drug Resistance, Microbial; Enrofloxacin; Feces; Female; Fluoroquinolones; Gentamicins; Multivariate Analysis; Netherlands; Odds Ratio; Prevalence; Quinolizines; Quinolones; Regression Analysis; Risk Factors; Salmonella; Salmonella Food Poisoning; Salmonella Infections, Animal; Surveys and Questionnaires; Swine; Swine Diseases

We have investigated the efficacy of colistin and ciprofloxacin, free or bound to polyalkylcyanoacrylate nanoparticles, for the targeting and eradication of Salmonella persisting in the organs of the mononuclear phagocyte system.. A model of persistent S. typhimurium infection was developed in C57BL/6 mice using i.v. inoculation of the plasmid-cured strain C53.. In vivo and ex vivo experiments showed that the persisting bacteria seem to evolve to a nongrowing state during experimental salmonellosis. In vivo treatment with free or nanoparticle-bound colistin did not significantly reduce the number of viable Salmonella C53, either in the liver or the spleen of infected mice. In contrast, in vivo treatment with ciprofloxacin led to a significant decrease of bacterial counts in the liver whatever the stage of infection and the form used. However, none of the treatments were able to sterilize the spleen or the liver. In ex vivo experiments, colistin was only active against bacteria recovered during the early phase of infection, whereas ciprofloxacin exerted its activity at all times postinfection.. We suggest that the micro-environment in which the bacterial cells persist in vivo probably causes dramatic changes in their susceptibility to antimicrobial agents.

Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Ciprofloxacin; Colistin; Cyanoacrylates; Drug Carriers; Female; Liver; Mice; Mice, Inbred C57BL; Microbial Sensitivity Tests; Particle Size; Salmonella Infections, Animal; Salmonella typhimurium; Spleen

An outbreak of salmonellosis caused by S. dublin has been prevalent in the Province of Gelderland ever since the end of 1975. The clinical picture is marked by general disease and respiratory symptoms, variations in temperature and diarrhoea which was present in not more than approximately 20 per cent of the cases. The most satisfactory results of treatment were obtained on administration of a sulphamethoxazole trimethoprim compound and colistin. Mortality averaged 16 per cent, the flock continuing to be affected with the disease for six weeks. In addition to enteritis, septicaemia and pneumonia were outstanding features in post-mortem studies. S. dublin was detected particularly in the liver, spleen and kidney. The sensitivity pattern showed a marked decrease during the past six to seven years, particularly sensitivity to chloramphenicol, tetracycline and ampicillin. The greater part of the strains were only sensitive to colistin, furazolidone and a sulphamethoxazole trimethoprim compound. This increase in resistance is discussed, and it is attributed to mass administration of antibodies rather than to transfer of resistance due to R-factors.

Topics: Animals; Cattle; Cattle Diseases; Colistin; Disease Outbreaks; Drug Resistance, Microbial; Drug Therapy, Combination; Female; Netherlands; Salmonella; Salmonella Infections, Animal; Sulfamethoxazole; Trimethoprim

Topics: Animals; Antibodies; Ascitic Fluid; Bacterial Vaccines; Bacteriological Techniques; Cattle; Colistin; Culture Media; Culture Techniques; Ethanol; Hot Temperature; Immune Sera; Immunity; Immunity, Cellular; Immunization; Injections, Intravenous; Injections, Subcutaneous; Macrophages; Mice; Phagocytosis; Salmonella; Salmonella Infections, Animal; Salmonella typhi