Antimicrobial agents resistance in Campylobacter coli from swine and humans

C. coli from slaughtered pigs and from human patients were examined for resistance to quinolones and tetracycline. Detection of tetO was performed. Gyrase A gene (gyrA) was amplified and sequenced and tested by an alternative method. Tetracycline resistance levels were respectively of 67,7 % and 56,3 % in swine and human isolates. In C. coli of human origin, all resistant isolates had the tetO determinant while 82,8 % of resistant C. coli from swine possessed it. Among the susceptible swine isolates, 17,2 % possessed this gene. Resistance to enrofloxacin (7,3 %) and ciprofloxacin (11,4 %) was observed in swine isolates and resistance for enrofloxacin (12,5 %) and ciprofloxacin (18,8 %) were observed in C. coli from humans. In addition, 72,7 % of swine resistant isolates and all isolates from humans had a mutation at position 86. Results were similar with MAMA-PCR which can thus be considered as a good alternative to sequencing

Antimicrobial Agent susceptibility of campyolobacter and salmonella from swine herds with various therapeutic regimens

Fecal samples were collected in pens from 27 farrow-to-finish swine herds using (n = 10) and not using fluoroquinolones (n = 17) and in herds using (n = 20) or not (n = 7) tetracycline. Workers on the farms participated to the study. Salmonella was found in 4 out of the 27 sampled herds and were all resistant to tetracycline and susceptible to enrofloxacin. No Salmonella and no Campylobacter were isolated from human. C. coli was found in all sampled herds with an average of 68,5 % positive pens. In farms not using quinolones and tetracycline, no resistance was observed among 2 herds but resistance to enrofloxacin (71 %) and to tetracycline (100 %) were observed in some farms. In herds where tetracycline was used, resistance levels varied from 7 % to 100 %. Resistance levels to quinolones in herds using this agent varied from 0 % to 100 %

Field trials to evaluate the efficacy of mash feed to reduce Salmonella shedding in swine

The objective of this study owas to evaluate the effect of corn based mash feed as a preharvest intervetion strategy to reduce shedding in pigs herds contaminated by Salmonella spp. In this study, three nurseries previously found contaminated by Salmonella in successive production cycles were selected to evaluate the effect of mash feed

Prevalence and-resistance patterns of Salmonella spp. serotypes from humans and production animals in Canada

The aim of the study was to compare the serotypes and antimicrobial resistance patterns of Salmonella from humans, pigs and poultry. Fecal samples were processed using conventional enrichment and culture procedures. Randomly selected isolates were tested against 12 different antimicrobial agents (ampicillin, amoxycillinlclavulamic acid, chloramphenicol, ceftiofur, enrofloxacin, gentamicin, neomycin, spectinocycin, streptomycin, sulfisoxazol, tetracyclin and sulfamethoxazol/trimetroprim) by the Kirby-Bauer technique. The prevalence of Salmonella was evaluated at 20,9% (18,9-23,0 %) in finishing pigs, 13,4% (12,0-14,9 %) in poultry and 2,9 (2,1-3,8 %) in humans. These isolates belonged to 22 different serotypes. Three serotypes were identified in all species, namely Typhimurium, Heidelberg and Agona. Multiple resistance was found in 26,7% of humans, 84,2 % of pigs and 71 ,4 % of poultry strains of S. Typhimurium. Antimicrobial resistance was thus commonly observed in humans, pigs and poultry isolates recovered in this study

Genotypic characterization of Salmonella Typhimurium isolates from humans, pigs and poultry in Canada

A total of 101 isolates of Salmonella enterica serovar Typhimurium were characterized in this study to evaluate the risk for human health associated with the presence of Salmonella isolates in pigs and poultry. Fifteen isolates recovered from human clinical specimens were compared to animal isolates. Isolates were recovered during the same period and in the same geographical area and characterized by establishing their genotypic and phenotypic profiles. All strains were characterized by phage-typing, antimicrobia l resistance patterns to various antimicrobial agents and pulsed-field gel electrophoresis (PFGE) of genomic DNA using Xba I and Spe I. The most frequently isolated phage type was phage type 104 in human (20,0 %), PT 104 in pig (40,2 %) and S. Typhimurium variant copenhagen I 04 in poultry (50,0 %). Spe I gave the highest index of discrimination among S. Typhimurium as evidenced by the variety of PFGE patterns obtained. The typing of the isolates showed that some animal and human strains were genetically related

Evaluation of the impact of functional foods on the course of Salmonella infection in piglets

With the aim to improve growth of weaning piglets and to minimize incidence of intestinal diseases, the effect of a combination of functional foods able to stimulate the development of systemic and mucosal immune system and to modulate bacterial populations in the gut was evaluated. In this study, we assessed the impact of functional foods on the course of Salmonella infection in piglets. Piglets from different litters were weaned at 21 days of age and assigned to 1 of the 4 feed additives (8 litters per treatment) as follow: 1-control (CTRL), 2-antibiotic (ATB), 3-cocktail of functional foods (CFF), 4-bovine colostrum + cocktail of functional foods (COL-CFF)

Identification of plasmids in a Salmonella Typhimurium septicemic isolate without the classical 95 kb virulence plasmid

In this study, we report the characterization of plasmids from a Salmonella Typhimurium strain isolated from a septicemic pig. This isolate did not possess the classical 95 kb plasmid associated with virulence, but contained several low molecular weight plasmids

Effect of mash feed on swine intestinal microflora and non-specific immune response.

Pelleting of feed was recommended in the past to reduce the risk of introduction of Salmonella in swine herds. However it was shown more recently that consumption of pelleted feed was associated with an increased probability of seropositivity Furthermore, several studies showed that the prevalence of Salmonella is decreased when mash feed is used. The objective of this study was to evaluate the effect of mash feed as a pre-harvest intervention strategy to prevent Salmonella colonization, to mod1fy of intestinal microflora and to stimulate of the immune system in swine

Impact of use of Tylosin and Virginiamycin on antimicrobial agents resistance profiles of Enterococcus spp. and E. coli isolates from swine in field conditions

Enterococcus spp. and E. coli are recognized as indicator microorganisms for the human and animal intestinal flora, and are also known to be potential reservoirs of antimicrobial resistance genes. Among the various use of antimicrobial agents that can promote antibioresistance, on farm use of growth promoters raises public health concerns. The aim of this study was to evaluate the impact of the use of selected growth promoters on antimicrobial resistance profiles of Enterococcus spp. and E. coli isolates from swine in field conditions. Enterococcus and E. coli isolates obtained from pooled fecal samples of pigs receiving Tylosin (44 ppm, n = 100) and Virginiamycin (22 ppm, n=1 00) were compared to isolates obtained from a control group (n = 1 00) fed without growth promoters, in field conditions. Comparison was done between isolates obtatned in the first week of treatment and isolates obtained 1n the 15th week

Protection of pigs against experimental Salmonella Typhimurium infection by use of a single dose subunit slow delivery vaccine

Infections caused by septicemic strains of Salmonella are significant animal health as well as food safety concerns for the North American swine industry. Among the various strategies to control these infections at the herd level, development of vaccines are attractive alternatives. In this study, based on previous studies of immune response to various protems following natural and experimental infections of pigs by Salmonella, we designed a subunit slow delivery vaccine and tested it in an experimental model of infection. The selected immunogenic protein was cloned and purified by chromatography. The purified protein was then incorporated m PLGA (a polymer that is slowly degraded within the animal\u27s gastro-intestinal system) microspheres and given orally once to groups of pigs (n=8) while control animals (n=8) received only PBS. Animals were challenged orally 4 weeks after the vaccmation with 108 cells of a virulent strains of Salmonella Typhimurium. Animals were examined twice a day and climcal signs evaluated using a predetermined scoring grid. Pigs were sacrificed 12 days later and bacterial cultures of vanous organs, electron microscopy and evaluation of lgA response by ELISA were performed. No significant difference was found at bacteriology and ELISA but marked differences in clinical signs were observed between vaccinated and non vaccinated animals. None of vaccmated animals showed fever exceeding 40°C while it was observed in 5 out of 8 non vaccinated Only one of vaccmated pigs showed mild diarrhea while severe diarrhea was observed in all control animals different sizes of microspheres were observed in intestinal crypts of vaccinated animals at electron microscopy. We concluded that this vaccine can protect pigs against clinical signs associated with experimental infection by Salmonella Typhimunum