Whole-genome sequences of Campylobacter coli and Campylobacter jejuni isolates from rhesus macaques (Macaca mulatta) with and without intestinal disease.

Campylobacter jejuni or Campylobacter coli infection can lead to post-infectious irritable bowel syndrome in humans and may produce a similar syndrome in rhesus macaques (Macaca mulatta). We report the complete genomes of 8 C. jejuni isolates and 103 C. coli isolates obtained from rhesus macaques with and without intestinal disease.

An Experimental Field Trial Investigating the Use of Bacteriophage and Manure Slurry Applications in Beef Cattle Feedlot Pens for Salmonella Mitigation.

Post-harvest Salmonella mitigation techniques are insufficient at addressing Salmonella harbored in cattle lymph nodes, necessitating the exploration of pre-harvest alternatives that reduce Salmonella prior to dissemination to the lymph nodes. A 2 × 2, unbalanced experiment was conducted to determine the effectiveness of pre-harvest treatments applied to the pen surface for Salmonella mitigation in cattle. Treatments included manure slurry intended to mimic pen run-off water (n = 4 pens), a bacteriophage cocktail (n = 4), a combination of both treatments (n = 5), and a control group (n = 5) that received no treatment. Environment samples from 18 feedlot pens and fecal grabs, hide swabs, and subiliac lymph nodes from 178 cattle were collected and selectively enriched for Salmonella, and Salmonella isolates were sequenced. The combination treatment was most effective at reducing Salmonella, and the prevalence was significantly lower compared with the control group for rump swabs on Days 14 and 21. The treatment impact on Salmonella in the lymph nodes could not be determined due to low prevalence. The reduction on cattle hides suggests that bacteriophage or water treatments applied to the feedlot pen surface may reduce Salmonella populations in cattle during the pre-harvest period, resulting in reduced contamination during slaughter and processing.

A Longitudinal Study on the Dynamics of Salmonella enterica Prevalence and Serovar Composition in Beef Cattle Feces and Lymph Nodes and Potential Contributing Sources from the Feedlot Environment.

Salmonella can persist in the feedlot pen environment, acting as a source of transmission among beef cattle. Concurrently, cattle that are colonized with Salmonella can perpetuate contamination of the pen environment through fecal shedding. To study these cyclical dynamics, pen environment and bovine samples were collected for a 7-month longitudinal comparison of Salmonella prevalence, serovar, and antimicrobial resistance profiles. These samples included composite environment, water, and feed from the feedlot pens (n = 30) and cattle (n = 282) feces and subiliac lymph nodes. Salmonella prevalence across all sample types was 57.7%, with the highest prevalence in the pen environment (76.0%) and feces (70.9%). Salmonella was identified in 42.3% of the subiliac lymph nodes. Based on a multilevel mixed-effects logistic regression model, Salmonella prevalence varied significantly (P < 0.05) by collection month for most sample types. Eight Salmonella serovars were identified, and most isolates were pansusceptible, except for a point mutation in the parC gene, associated with fluoroquinolone resistance. There was a proportional difference in serovars Montevideo, Anatum, and Lubbock comparing the environment (37.2, 15.9, and 11.0%, respectively), fecal (27.5, 22.2, and 14.6%, respectively), and lymph node (15.6, 30.2, and 17.7%, respectively) samples. This suggests that the ability of Salmonella to migrate from the pen environment to the cattle host-or vice versa-is serovar specific. The presence of certain serovars also varied by season. Our results provide evidence that Salmonella serovar dynamics differ when comparing environment and host; therefore, developing serovar-specific preharvest environmental Salmonella mitigation strategies should be considered. IMPORTANCE Salmonella contamination of beef products, specifically from the incorporation of bovine lymph nodes into ground beef, remains a food safety concern. Current postharvest Salmonella mitigation techniques do not address Salmonella bacteria that are harbored in the lymph nodes, nor is it well understood how Salmonella invades the lymph nodes. Alternatively, preharvest mitigation techniques that can be applied to the feedlot environment, such as moisture applications, probiotics, or bacteriophage, may reduce Salmonella before dissemination into cattle lymph nodes. However, previous research conducted in cattle feedlots includes study designs that are cross-sectional, are limited to point-in-time sampling, or are limited to sampling of the cattle host, making it difficult to assess the Salmonella interactions between environment and hosts. This longitudinal analysis of the cattle feedlot explores the Salmonella dynamics between the feedlot environment and beef cattle over time to determine the applicability of preharvest environmental treatments.

Prevalence and Profiles of Antibiotic Resistance Genes mph(A) and qnrB in Extended-Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli Isolated from Dairy Calf Feces.

The use of antibiotics to treat dairy calves may result in multidrug-resistant extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. This study investigated fluoroquinolone and macrolide resistance genes among ESBL-producing E. coli isolated from dairy calves. Fresh fecal samples from 147 dairy calves across three age groups were enriched to select for ESBL-producing E. coli. Plasmid-mediated fluoroquinolone (qnrB), macrolide (mph(A)), and beta-lactam (blaCTX-M groups 1 and 9) resistance genes were identified by PCR and gel electrophoresis in ESBL-producing E. coli. Beta-lactamase variants and antibiotic resistance genes were characterized for eight isolates by whole-genome sequencing. Seventy-one (48.3%) samples were positive for ESBL-producing E. coli, with 159 (70.4%) isolates identified as blaCTX-M variant group 1 and 67 (29.6%) isolates as blaCTX-M variant group 9. Resistance gene mph(A) was more commonly associated with blaCTX-M variant group 1, while resistance gene qnrB was more commonly associated with variant group 9. E. coli growth was quantified on antibiotic media for 30 samples: 10 from each age group. Significantly higher quantities of ceftriaxone-resistant E. coli were present in the youngest calves. Results indicate the dominant blaCTX-M groups present in ESBL-producing E. coli may be associated with additional qnrB or mph(A) resistance genes and ESBL-producing E. coli is found in higher abundance in younger calves.

Circulating Short-Chain Fatty Acids in Preterm Birth: A Pilot Case-Control Study.

Short-chain fatty acids (SCFAs) are by-products from microbial metabolism of fibers with anti-inflammatory effects. SCFAs may mitigate inflammatory conditions such as obesity through modulation of histone acetylation. Lipid metabolism and inflammation play critical roles during pregnancy. However, few studies have examined maternal SCFAs in relation to pregnancy outcomes. This pilot study examined plasma SCFAs in spontaneous preterm birth. This study used stored plasma from an existing cohort to measure seven (proponic acid, methanoic acid, butanoic acid, isovaleric acid, pentanoic acid, methylpropylbutanoic and methylbutanoic acids) SCFAs in 20 women with spontaneous preterm delivery (< 37 weeks gestation) and 30 women with a healthy term delivery (≥ 37 weeks gestation). All women had singleton pregnancies and provided serum at the time of admission to labor and delivery. SCFAs were measured by purge and trap gas chromatography/mass spectrometry. SCFAs were log transformed. Logistic regression with penalized likelihood approach examined associations between SCFAs and preterm birth, adjusting for age, BMI, and race. We also explored if SCFAs had a linear association with pre-pregnancy BMI. Propionic acid had a negative association with preterm birth [odds ratioadj: 0.56, 95% confidence interval 0.41-0.86). There was a negative association between propionic acid and BMI after adjustments (ß = -0.14, p = 0.0011). No other associations were found. Lower levels of propionic acid were associated with preterm birth and correlated with higher BMI. Larger studies should explore if circulatory SCFAs protect against inflammatory pathways during pregnancy and are associated with adverse outcomes when measured earlier in pregnancy.

Interferon epsilon in the reproductive tract of healthy and genital herpes simplex virus-infected pregnant women: Results of a pilot study.

PROBLEM: Recently characterized interferon epsilon (IFNe) protects against sexually transmitted infections, including genital herpes simplex virus (HSV), in animal models. There are no reports of IFNe in genital tract secretions of pregnant women, and data on IFNe in non-pregnant women are limited. This pilot study is the first to measure concentrations of IFNe in vaginal and cervical secretions during pregnancy and compare values between healthy and genital HSV-infected women. METHOD OF STUDY: Vaginal or cervical specimens from 30 pregnant women were obtained from the Global Alliance to Prevent Prematurity and Stillbirth (GAPPS) repository. Cervical samples were collected during the first trimester and vaginal samples across pregnancy. Enzyme-linked immunosorbent assay determined concentrations of IFNe (pg/mL). Data for IFNe were log-transformed and compared by maternal demographics, clinical variables, and HSV status using t tests and linear regression. Repeated measures analysis explored trends across pregnancy. RESULTS: Among the entire cohort, first trimester concentrations of IFNe in vaginal or cervical secretions decreased as body mass index increased (ß = -0.14, P = .0466). Concentrations of vaginal IFNe increased across pregnancy in HSV-infected and healthy women (P = .009). Average vaginal IFNe across pregnancy was lower in women with HSV compared to healthy women (P = .0009). CONCLUSION: Interferon epsilon increased across pregnancy, but was less abundant in women with HSV. This pilot investigation cannot make any definitive conclusions. However, animal models suggest that IFNe may protect against STIs. Thus, larger studies are required to validate expression of IFNe in the reproductive tract of pregnant women with and without genital infections.