cefoxitin and Swine-Diseases

The presence of Staphylococcus spp. resistant to methicillin in the nasal cavity of swine has been previously reported. Considering the possible occurrence of bacterial resistance and presence of resistance genes in intensive swine breeding and the known transmissibility and dispersion potential of such genes, this study aimed to investigate the prevalence of resistance to different antibiotics and the presence of the mecA resistance gene in Staphylococcus spp. from piglets recently housed in a nursery. For this, 60 nasal swabs were collected from piglets at the time of their housing in the nursery, and then Staphylococcus spp. were isolated and identified in coagulase-positive (CoPS) and coagulase-negative (CoNS) isolates. These isolates were subjected to the disk-diffusion test to evaluate the bacterial resistance profile and then subjected to molecular identification of Staphylococcus aureus and analyses of the mecA gene through polymerase chain reaction. Of the 60 samples collected, 60 Staphylococcus spp. were isolated, of which 38 (63.33%) were classified as CoNS and 22 (36.67%) as CoPS. Of these, ten (45.45%) were identified as Staphylococcus aureus. The resistance profile of these isolates showed high resistance to different antibiotics, with 100% of the isolates resistant to chloramphenicol, clindamycin, and erythromycin, 98.33% resistant to doxycycline, 95% resistant to oxacillin, and 85% resistant to cefoxitin. Regarding the mecA gene, 27 (45%) samples were positive for the presence of this gene, and three (11.11%) were phenotypically sensitive to oxacillin and cefoxitin. This finding highlights the importance of researching the phenotypic profile of resistance to different antimicrobials and resistance genes in the different phases of pig rearing to identify the real risk of these isolates from a One Health perspective. The present study revealed the presence of samples resistant to different antibiotics in recently weaned production animal that had not been markedly exposed to antimicrobials as growth promoters or even as prophylactics. This information highlights the need for more research on the possible sharing of bacteria between sows and piglets, the environmental pressure within production environments, and the exposure of handlers during their transport, especially considering the community, hospital, and political importance of the presence of circulating resistant strains.

Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Cefoxitin; Coagulase; Female; Microbial Sensitivity Tests; Nasal Cavity; Oxacillin; Penicillin-Binding Proteins; Staphylococcal Infections; Staphylococcus; Staphylococcus aureus; Swine; Swine Diseases

A total of 80 sows (Line 241; DNA, Columbus, NE) across three farrowing groups were used in a study to evaluate the effect of feeding live yeast and yeast extracts to lactating sows on sow and litter performance and antimicrobial resistance (AMR) patterns of sow fecal E. coli. Sows were blocked by farrowing group, BW, and parity on day 110 of gestation and allotted to 1 of 2 dietary treatments. Dietary treatments consisted of a standard lactation diet with or without yeast-based pre- and probiotics (0.10% Actisaf Sc 47 HR+ and 0.025% SafMannan; Phileo by Lesaffre, Milwaukee, WI). Diets were fed from day 110 of gestation until weaning (approximately d 19 post-farrow). A tendency (P = 0.073) was observed for increased feed intake through lactation when sows were fed a diet with yeast additives compared with the control diet. There was no evidence (P > 0.10) that treatment influenced any other sow or litter performance measurements. Fecal samples were collected upon entry into the farrowing house and at weaning from the first farrowing group (27 sows) to determine the resistance patterns of E. coli. E. coli was isolated from fecal samples and species confirmed by PCR detection of uidA and clpB genes. Microbroth dilution method was used to determine the minimal inhibitory concentrations (MIC) of E. coli isolates to 14 antimicrobials. Isolates were categorized as either susceptible, intermediate, or resistant based on Clinical and Laboratory Standards Institute guidelines. An interaction (P = 0.026) of diet × sampling day was observed for cefoxitin where fecal E. coli showed no evidence of treatment differences (P = 0.237) in MIC values at entry, but sows fed the control diet had lower (P = 0.035) MIC values at weaning compared with sows fed yeast additives. There were no diet main effects (P > 0.10) on the resistance of fecal E. coli. There was an increased (P < 0.02) toward resistance for 11 of the 14 antimicrobials over time. Fecal E. coli were resistant to tetracycline and ceftriaxone at weaning. Fecal E. coli were susceptible or intermediate in all sampling days to the remaining antimicrobials. In conclusion, feeding live yeast and yeast extracts tended to increase feed intake during lactation but did not influence either sow or litter performance measurements or the resistance of fecal E. coli during lactation except for cefoxitin, which had a higher MIC at the end of lactation when yeast additives were present in the diet.. Feeding sows live yeast and yeast extracts from day 110 of gestation through lactation tended to increase lactation feed intake but did not affect any other sow or litter performance criteria. Live yeast and yeast extracts in the diet had minimal effect on the antimicrobial resistance of fecal E. coli isolates. Regardless of the diet, fecal E. coli isolates were susceptible to 11 of the 14 antimicrobials when sows entered the farrowing house. But most of the antimicrobials were classified as intermediate or with a tendency toward resistance at weaning even though none of these antibiotics were used during the lactation period. Our findings agree with other cross-sectional studies on AMR where high AMR gene levels reported among young pigs were attributed to sow population.

Topics: Animal Feed; Animals; Anti-Bacterial Agents; Cefoxitin; Diet; Drug Resistance, Bacterial; Escherichia coli; Escherichia coli Infections; Female; Lactation; Litter Size; Parity; Pregnancy; Probiotics; Swine; Swine Diseases; Weaning; Yeasts

A total of 690 pathogenic Escherichia (E.) coli isolates from weaned piglets were examined for antimicrobial resistance phenotypes, resistance genes, and virulence gene profiles. Also, 29 enterotoxigenic E. coli (ETEC) and 35 Shiga-toxin producing E. coli (STEC) isolates were analyzed using multi-locus sequence typing (MLST). Comparisons of the associations between antimicrobial resistance phenotypes, resistance genes, and virulence genes were performed separately by assessing odds ratio (OR). Although majorities of associations were not confirmed however, we found that associations between specific virulence factors-antimicrobial resistance. F18 encoding isolates showed association with resistance to cefazolin (OR = 3.08) and cefoxitin (OR = 3.65), and also with antimicrobial resistance gene mcr-3 (OR = 4.58). There was a high correlation between F4-STb (OR = 13.56), F4-LT (OR = 8.77), F4-EAST-I (OR = 4.97), and F18-Stx2e (OR = 3.83). Most of ETEC (21 of 29, 72.4%) isolates were assigned to ST100, and 20 of 35 STEC isolates (57.1%) were ST1. There were 5 clusters, and each cluster showed specific antimicrobial resistance patterns. Cluster I showed resistance to gentamicin, streptomycin, neomycin, nalidixic acid, ciprofloxacin, norfloxacin, trimethoprim / sulfamethoxazole, and tetracyclines whereas, cluster V showed resistance to ampicillin, amoxicillin / clavulanic acid, cephalothin, cefoxitin, cefazolin, norfloxacin, and colistin. Although there is need to do more experiments to clarify why certain virulence factors showed relationship with antimicrobial resistance, it is clear that there is a significant association between specific virulence genes and antimicrobial resistance in E. coli from weaned piglets with enteric colibacillosis in Korea.

Topics: Animals; Anti-Bacterial Agents; Cefazolin; Cefoxitin; Diarrhea; Drug Resistance, Bacterial; Enterotoxigenic Escherichia coli; Escherichia coli Infections; Multilocus Sequence Typing; Norfloxacin; Swine; Swine Diseases; Virulence Factors