Similarities in seroprevalence of Toxoplasma gondii, Trichinella spp., Trichuris suis and Ascaris suum in swine in the conventional and antibiotic free swine production systems

Helmith parasite infections in swine represent a significant, but understudied health concern for both the swine industry and consumers. While many parasitic infections cause subclinical infections, infected swine pose a public health risk from consumption of contaminated meat products

Molecular Epidemiology of Salmonella enterica and Subtyping Using Phenotypic and Genotypic Approaches

The aim of this study was to evaluate the discriminatory power of two phenotyping and three genotyping methods commonly used to subtype Salmonella in swine and other hosts. We found AFLP and PFGE to have the highest and comparable discriminatory power to each other. Among the 202 isolates analyzed in this study, using AFLP, 16 cluster types of S. Typhimurium were identified. Vertical spread in the production chain, from nursery to finishing farms and vertical as well as horizontal spread among finishing farms appeared to be important means of Salmonella serovar Typhimurium dissemination in swine units

Prevalence and antimicrobial resistance of Salmonella isolated from conventional and antimicrobial-free (ABF) swine herds in North Carolina

The main objective of this stdy was to compare prevalence and antimicrobial resistance of Salmonella isolated from swine reared in antimicrobial-free (ABF) and conventional production systems in North Carolina

Polymyxins leading to nephrotoxicity

Drug resistance gram-negative bacteria are the most hazardous type of germ because they cause life-threatening illnesses. Polymyxins are cyclic lipodecapeptide antibiotics that are effective against gram-negative bacteria like Acinetobacter, Pseudomonas, and other Enterobacteriaceae (such Klebsiella, Escherichia coli, and Serratia). Polymyxins kill bacteria by rupturing the bacterial outer membrane (OM). The main side effect of this antibiotic class is the development of kidney damage. Transposable genetic elements, such as MCR genes, can encode bacterial resistance to polymyxins. Colistin's prodrug is colistimethate sodium (CMS). Polymyxin dosage should be modified based on renal function. Polymyxins have demonstrated excellent clinical results, which have aided in the development of a better dosage regimen. Monte Carlo simulations were used to determine the most effective polymyxin dosages. Polymyxin resurgence has resulted in the eradication of multidrug resistant gram negative bacteria

Comparison of multidrug resistant Salmonella between intensively - and extensively-reared antimicrobial - free (ABF) swine herds

This cross-sectional study was conducted to determine the prevalence and antimicrobial resistance of Salmonella species in swine reared in the intensive (indoor) and extensive (outdoor) ABF production systems at farm and slaughter in North Carolina, U.S.A. We sampled a total of 279 pigs at farm (Extensive 107; Intensive 172) and collected 274 carcass swabs (Extensive 124; Intensive 150) at slaughter. Salmonella species were tested for their susceptibility against 12 antimicrobial agents using the Kirby-Bauer disk diffusion method. Serogrouping was done using polyvalent and group specific antisera. A total of 400 salmonellae were isolated in this study with a significantly higher Salmonella prevalence from the Intensive (30%) than the extensive farms (0.9%) (P \u3c 0.001 ). At slaughter, significantly higher Salmonella was isolated at the pre and post-evisceration stages from extensively (29 % pre-evisceration and 33.3 % post-evisceration) than the intensively (2 % pre-ev1sceration and 6 % post-evisceration) reared swine (P \u3c 0.001 ). The isolates were clustered in six serogroups including B, C, E1, E4, G and R. Highest frequency of antimicrobial resistance was observed against tetracycline (78.5%) and streptomycin (31 .5%). A total of 13 antimicrobial resistance patterns were observed including the pentaresistant strains with ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline resistance pattern observed only among isolates from the intensive farms (n=28) and all belonged to serogroup B. This study shows that multidrug resistant Salmonella are prevalent in ABF production systems despite the absence of antimicrobial selection pressure

Development of a Microarray system for the Rapid and Simultaneous Detection of Bacterial and Viral Foodborne Pathogens

Foodborne diseases are increasingly recognized as a significant global public health problem despite major advances and improvements in the quality of food, water, sanitation and hygiene. However, detection and characterization of foodborne pathogens during outbreak scenarios remains a laborious and time-consuming task. The aim of this work was to develop an oligonucleotide microarray for rapid detection and characterization of the most important infectious bacterial (Campylobacter, Salmonella and Yersinia) and viral (Noroviruses) pathogens found in swine and associated pork products. A total of 272 target regions and genes were identified that were specific for pathogen identification and characterization of specific antimicrobial resistance and virulence determinants. We designed multiple probes (up to three) per gene to increase the sensitivity and specificity of the microarray. After BLAST analysis, a total of 562 probes were finally selected to be printed on to glass slides. Appropriate control strains that were previously characterized in our laboratories by PCR were selected to test the developed arrays. Preliminary results indicated that the designed probes were highly specific and sensitive for identification of tested pathogens and known res1stance and virulence genes present in the selected control strains

Phenotypic heterogeneity of Campylobacter coli isolated from conventional and antimicrobial free swine at farm and slaughter

The aim of this study was to determine the phenotypic and genotypic diversity of multiple Campylobacter coli isolates (n = 3) present in the same pig fecal and carcass samples at fann and slaughter, respectively. We isolated 1459 C. coli (1110 on farm and 349 from slaughter) from 908 pigs and 757 carcasses and characterized them for their antimicrobial susceptibility profile to a panel of six antimicrobials using the agar dilution method. A subset of 40 isolates representing 10 pigs and eight carcass samples were further genotyped by multi-locus sequence typing (MLST). Phenotypic diversity of C. coli isolates at the four fold minimum inhibitory concentration (MIC) levels within the same sample was detected in 39% (n = 192) pigs and 40.2% (n = 58) carcass swabs with no significant difference between the two sources (P = 0.721). Phenotypic heterogeneity based on the resistance patterns was observed in 32.5% (n = 162) of the farm samples and in 30.5% (n = 44) carcass swabs at slaughter (P = 0.64). Genotypic diversity based on MLST was detected in the 40 isolates which were represented by 22 sequence types (ST). In conclusion, we detected multiple C. coli subtypes from individual pig or carcass samples. Our study clearly signifies the importance of testing multiple colonies to make appropriate and valid conclusions in epidemiological based studies

Campylobacter Prevalence and Diversity in Antimicrobial Free and Conventionally Reared Market Swine

The objectives of this study were to determine the prevalence and antimicrobial resistance of Campylobacter spp. among pigs raised antimicrobial free (ABF) and those raised conventionally. Bacterial isolation was done on-farm and at slaughter using conventional methods and antimicrobial susceptibility tests were done for 12 antimicrobials using Kirby-Bauer and epsilometric test (E-test) methods. All 14 herds were positive for Campylobacter. On-farm prevalence among ABF herds was 71% and 81% among conventional herd. In contrast, the prevalence among carcass swabs was higher among ABF herds than conventional herds with 60% and 29% respectively. There was significant reduction after chilling in all groups (p\u3c0.05). On-farm frequency of antimicrobial resistance was significantly higher among isolates from conventional herds than ABF (p\u3c0.05). In contrast frequency of resistance to five of the seven antimicrobials was higher among carcass swabs of ABF herds than conventional herds

Campylobacter prevalence and antimicrobial resistance in swine reared in antimicrobial-free and conventional production systems

The objective of this study was to determine and compare the prevalence and antimicrobial resistance of Campylobacter species in swine reared in the conventional and antimicrobial free production (ABF) production systems as part of a multi-state study. To date, 19 conventional and 16 ABF groups have been followed

Prevalence and Antimicrobial Resistance of Salmonella, E. coli, and Campylobacter in Pigs from Swine Producing States in the United States

The purpose of the study was to determine the prevalence and antimicrobial susceptibility of Salmonella, Campylobacter and generic E. coli (commensal bacteria which may harbor antimicrobial resistance genes) from swine feces collected over one year from the top three swine producing states (Iowa, North Carolina, and Minnesota), which represent 51% of the total pig crop in the U.S, plus Ohio. The prevalence of Salmonella (n=462/4426), Campylobacter (n=994/1184) and E. coli (n=833/845) at the sample level was 10.4%, 98.6% and 83.6%, respectively