Effects of concentrated poultry operations and cropland manure application on antibiotic resistant Escherichia coli and nutrient pollution in Chesapeake Bay watersheds

Migration of phosphorus in pig manure during pyrolysis process and slow-release mechanism of biochar in hydroponic application

Pyrolysis is an effective method for treating of livestock and poultry manure developed in recent years. It can completely decompose pathogens and antibiotics, stabilize heavy metals, and enrich phosphorus (P) in biochar. To elucidate the P migration mechanism under different pig manure pyrolysis temperatures, sequential fractionation, solution 31P nuclear magnetic resonance, X-ray photoelectron spectroscopy, X-ray diffraction, and K-edge X-ray absorption near-edge structure techniques were used to analyze the P species in pig manure biochar (PMB). The results indicated that most of the organic P in the pig manure was converted to inorganic P during pyrolysis. Moreover, the transformation to different P groups pathways was clarified. The phase transition from amorphous to crystalline calcium phosphate was promoted when the temperature was above 600 °C. The content of P extracted by hydrochloric acid, which was the long-term available P for plant uptake, increased significantly. PMB pyrolyzed at 600 °C can be used as a highly effective substitute for P source. It provides the necessary P species (e.g. water-soluble P.) and metal elements for the growth of water spinach plants, and which are slow-release comparing with the Hogland nutrient solution.

Sports and sustainable development: the troubling absence of meat sourcing policies in the sports sector

The excessive use of antibiotics in industrial meat production in the U.S. incurs severe health implications for animals, humans, and the environment, thereby threatening the integrated health of the ecosystem and sustainable development. While the consumption of meat, including hot dogs, chicken wings, and hamburgers, is a hallmark of attending professional sports events in North America, the sourcing policies for meat in the realm of professional sports remain relatively obscure. We conducted a content analysis case study on the four major sports leagues in North America, their teams and stadium practices. Our objective was twofold: first, to investigate existing sustainability initiatives at the league, team, and stadium levels; and second, to examine whether there are any food sourcing programs, specifically meat sourcing policies that might encourage the consumption of meat produced without the use of antibiotics, in the sports sector that are designed to mitigate ecological ramifications of meat consumption within sports contexts. Results show that existing sustainability initiatives at the three levels are focused primarily on reducing carbon emissions and waste. There is, however, a notable neglect of food sourcing policies, which is concerning given that industrial animal agriculture is a leading cause of antibiotic resistance and environmental degradation. This suggests that meat sourcing policy is a missing piece in current sustainability initiatives. The major sports leagues should therefore consider incorporating pertinent policies, such as procuring meat-based products produced without the use of antibiotics to help strengthen their existing efforts in achieving their sustainable development goals.

Geospatial and co-occurrence analysis of antibiotics, hormones, and UV filters in the Chesapeake Bay (USA) to confirm inputs from wastewater treatment plants, septic systems, and animal feeding operations

Previous studies have reported select contaminants of emerging concern (CECs) in limited areas of the Chesapeake Bay (USA), but no comprehensive efforts have been conducted. In this work, 43 antibiotics, 9 hormones, 11 UV filters, and sucralose, were measured in matched water, sediment, and oyster samples from 58 sites. The highest sucralose concentration was 3051 ng L-1 in a subwatershed with 4.43 million liters of wastewater effluent per day (MLD) and 4385 septic systems. Although antibiotic occurrence was generally low in subwatersheds located in less populated areas, 102 ng L-1 ciprofloxacin was detected downstream of 0.58 MLD wastewater effluent and 10 animal feeding operations. Hormones were not regularly detected in water (2%) or oysters (37%), but the high detection frequencies in sediment (74%) were associated with septic systems. UV filters were ubiquitously detected in oysters, and octisalate exhibited the highest concentration (423 ng g-1). Oyster-phase oxybenzone and aqueous-phase sucralose concentrations were significantly correlated to wastewater effluent and septic systems, respectively. Toxicity outcomes were predicted for homosalate and octisalate throughout the Bay, and antimicrobial resistance concerns were noted for the Chester River. The geospatial and co-occurrence relationships constitute crucial advances to understanding CEC occurrence in the Chesapeake Bay and elsewhere.

Risk factors for extended-spectrum beta-lactamase (ESBL)-producing E. coli carriage among children in a food animal-producing region of Ecuador: A repeated measures observational study

BACKGROUND

The spread of antibiotic-resistant bacteria may be driven by human-animal-environment interactions, especially in regions with limited restrictions on antibiotic use, widespread food animal production, and free-roaming domestic animals. In this study, we aimed to identify risk factors related to commercial food animal production, small-scale or "backyard" food animal production, domestic animal ownership, and practices related to animal handling, waste disposal, and antibiotic use in Ecuadorian communities.

METHODS AND FINDINGS

We conducted a repeated measures study from 2018 to 2021 in 7 semirural parishes of Quito, Ecuador to identify determinants of third-generation cephalosporin-resistant E. coli (3GCR-EC) and extended-spectrum beta-lactamase E. coli (ESBL-EC) in children. We collected 1,699 fecal samples from 600 children and 1,871 domestic animal fecal samples from 376 of the same households at up to 5 time points per household over the 3-year study period. We used multivariable log-binomial regression models to estimate relative risks (RR) of 3GCR-EC and ESBL-EC carriage, adjusting for child sex and age, caregiver education, household wealth, and recent child antibiotic use. Risk factors for 3GCR-EC included living within 5 km of more than 5 commercial food animal operations (RR: 1.26; 95% confidence interval (CI): 1.10, 1.45; p-value: 0.001), household pig ownership (RR: 1.23; 95% CI: 1.02, 1.48; p-value: 0.030) and child pet contact (RR: 1.23; 95% CI: 1.09, 1.39; p-value: 0.001). Risk factors for ESBL-EC were dog ownership (RR: 1.35; 95% CI: 1.00, 1.83; p-value: 0.053), child pet contact (RR: 1.54; 95% CI: 1.10, 2.16; p-value: 0.012), and placing animal feces on household land/crops (RR: 1.63; 95% CI: 1.09, 2.46; p-value: 0.019). The primary limitations of this study are the use of proxy and self-reported exposure measures and the use of a single beta-lactamase drug (ceftazidime with clavulanic acid) in combination disk diffusion tests for ESBL confirmation, potentially underestimating phenotypic ESBL production among cephalosporin-resistant E. coli isolates. To improve ESBL determination, it is recommended to use 2 combination disk diffusion tests (ceftazidime with clavulanic acid and cefotaxime with clavulanic acid) for ESBL confirmatory testing. Future studies should also characterize transmission pathways by assessing antibiotic resistance in commercial food animals and environmental reservoirs.

CONCLUSIONS

In this study, we observed an increase in enteric colonization of antibiotic-resistant bacteria among children with exposures to domestic animals and their waste in the household environment and children living in areas with a higher density of commercial food animal production operations.

Prospects of dietary seaweeds and their bioactive compounds in sustainable poultry production systems: A symphony of good things?

Modern poultry production systems face numerous economic, environmental, and social sustainability challenges that threaten their viability and acceptability as a major source of animal protein. As scientists and producers scramble to find cost-effective and socially acceptable solutions to these challenges, the dietary use of marine macroalgae (seaweeds) could be an ingenious option. Indeed, the incredible array of nutritive and bioactive compounds present in these macroscopic marine organisms can be exploited as part of sustainable poultry production systems of the future. Incorporating seaweeds in poultry diets could enhance feed utilization efficiency, growth performance, bird health, meat stability and quality, and consumer and environmental health. Theoretically, these benefits are mediated through the putative antiviral, antibacterial, antifungal, antioxidant, anticarcinogenic, anti-inflammatory, anti-allergic, antithrombotic, neuroprotective, hypocholesterolemic, and hypoglycemic properties of seaweed bioactive compounds. Despite this huge potential, exploitation of seaweed for poultry production appears to be constrained by a variety of factors such as high fibre, phenolics, and ash content. In addition, conflicting findings are often reported when seaweeds or their extracts are used in poultry feeding trials. Therefore, the purpose of this review paper is to collate information on the production, phytochemical components, and nutritive value of different seaweed species. It provides an overview ofin vivoeffects of dietary seaweeds as measured by nutrient utilization efficiency, growth performance, and product quality and stability in poultry. The utility of dietary seaweeds in sustainable poultry production systems is explored, while gaps that require further research are highlighted. Finally, opportunities that exist for enhancing the utility of seaweeds as a vehicle for sustainable production of functional poultry products for better global food and nutrition security are presented.

Exposure to industrial hog operations and gastrointestinal illness in North Carolina, USA

With 9 million hogs, North Carolina (NC) is the second leading hog producer in the United States. Most hogs are housed at concentrated animal feeding operations (CAFOs), where millions of tons of hog waste can pollute air and water with fecal pathogens that can cause diarrhea, vomiting, and/or nausea (known as acute gastrointestinal illness (AGI)). We used NC's ZIP code-level emergency department (ED) data to calculate rates of AGI ED visits (2016-2019) and swine permit data to estimate hog exposure. Case exposure was estimated as the inverse distances from each hog CAFO to census block centroids, weighting with Gaussian decay and by manure amount per CAFO, then aggregated to ZIP code using population weights. We compared ZIP codes in the upper quartile of hog exposure ("high hog exposed") to those without hog exposure. Using inverse probability of treatment weighting, we created a control with similar demographics to the high hog exposed population and calculated rate ratios using quasi-Poisson models. We examined effect measure modification of rurality and race using adjusted models. In high hog exposed areas compared to areas without hog exposure, we observed a 11% increase (95% CI: 1.06, 1.17) in AGI rate and 21% increase specifically in rural areas (95% CI: 0.98, 1.43). When restricted to rural areas, we found an increased AGI rate among American Indian (RR = 4.29, 95% CI: 3.69, 4.88) and Black (RR = 1.45, 95% CI: 0.98, 1.91) residents. The association was stronger during the week after heavy rain (RR = 1.41, 95% CI: 1.19, 1.62) and in areas with both poultry and swine CAFOs (RR = 1.52, 95% CI: 1.48, 1.57). Residing near CAFOs may increase rates of AGI ED visits. Hog CAFOs are disproportionally built near rural Black and American Indian communities in NC and are associated with increased AGI most strongly in these populations.

Assessment Impacts of Ozone on Salmonella Typhimurium and Escherichia coli O157:H7 in Liquid Dairy Waste

Liquid dairy manure, which is produced in enormous quantities in flush dairy manure management systems, is commonly used as an alternative to chemical fertilizers. It provides nutrient benefits to crops and soils. While dairy waste is a well-accepted and widely used fertilizer, the presence of indicator organisms and human pathogens in manure may lead to pathogen contamination in crops and soils. This study is focused on the examination of ozone gas-based sterilization. In the past, ozone (O3) has been used for sanitizing various foods and solid surfaces, but the potential of O3 for eliminating human pathogens in liquid dairy waste is not studied yet. Pathogens such as Salmonella Typhimurium and Escherichia coli O157:H7 are reported to be present in liquid dairy manure, and this research evaluated the effects of various levels of ozone on the survival of these two pathogens. We designed a continuous type O3 treatment system that has four major components: (1) ozone generator using oxygen; (2) ozone concentration control by mixing with pure air; (3) continuous monitoring of ozone concentrations; and (4) ozone experiment chambers. Various levels of ozone (43.26, 87.40, and 132.46 mg·L−1) were produced in the ozone system, and subsequently, ozone was diffused through liquid manure. Liquid manure was exposed to ozone for multiple durations (30, 60, and 120 min). To determine the effectiveness of O3 in eliminating pathogens, time-series samples were collected and analyzed for determining the levels of S. typhimurium and E. coli O157:H7. Preliminary results showed that ozone concentrations of 132.46 mg/L, and exposure time of 120 min resulted in the reduced levels of E. coli and Salmonella. Low levels of ozone and limited exposure time were found to be less effective in pathogen removal potentially due to high solid contents. Additional studies carrying out experiments to evaluate the impacts of solids in combination with ozone concentrations will provide further insights into developing full-scale ozone-based treatment systems.

Prairie strips' effect on transport of antimicrobial resistance indicators in poultry litter

Poultry litter is a valuable nutrient resource for agricultural production but is also a potential source for introducing antibiotic resistance genes (ARGs) and litter-associated bacteria (LAB) to the environment. Prairie strips have been demonstrated as an effective conservation practice to improve environmental quality in agroecosystems. This research aims to assess prairie strips' potential for reducing the transport of LAB and ARGs in runoff after litter application. Plot-scale rainfall simulations were performed using a replicated block design, with soil and surface runoff samples taken during the rainfall event. Microbial taxa and ARGs were characterized in the litter, soil, and water samples. In plots with litter application, LAB and ARGs were mainly detected in runoff, with very low detection in soils. Detection of ARGs in runoff, irrespective of strip installations, is consistent with previous observations of litter as a source of antimicrobial resistance (AMR) risks. The effectiveness of prairie strips to remove LAB and ARGs varied. In two of the three prairie strip plots, fewer AMR indicators were detected relative to control plots, suggesting that the prairie strips can potentially reduce these risks. In one plot, which was also associated with increased flow rate, we observed increased AMR indicators despite the installation of a prairie strip. Our observations highlight the need to prioritize understanding of soil properties even within the same site. Although we show that prairie strips can potentially reduce AMR risks, further research is needed to better understand the influence of rainfall timing, soil, and litter characteristics.

MoS2 nanosheets loaded on collapsed structure zeolite as a hydrophilic and efficient photocatalyst for tetracycline degradation and synergistic mechanism

In this study, MoS₂@Z photocatalysts were synthesized by combining ultrasonic and hydrothermal methods, and used for the degradation of tetracycline. The structure characteristics and photocatalytic degradation mechanism of photocatalysts were also systematically investigated. The obtained MoS₂@Z-5 exhibits the highest photo-degradation efficiency of tetracycline (87.23%), which is 3.58 times more than alkali-modified zeolite (24.34%) and 1.80 times more than pure MoS₂ (48.53%). Furthermore, the MoS₂@Z-5 showed significant stability in three times photocatalytic recycles and the removal efficiency only decrease by 9.03%. Crystal structure and micromorphology analysis show modified zeolite with collapsed structure can regulate the morphology of nano-MoS₂ and make MoS₂ appear fault structure, which can expose more active sites. In addition, low Si/Al ratio zeolite increases the hydrophilia of MoS₂@Z-5. Reactive-species-trapping experiments show that the hole is the main reactive oxidizing species. The superior photo-degradation efficiency is mainly attributed to outstanding hydrophilia, exposure of the edge active sites, and efficient separation of photogenerated charge and holes. A possible photocatalytic mechanism and degradation pathways of tetracycline were proposed. The results indicate that MoS₂@Z-5 may become an efficient, stable, and promising photocatalyst in tetracycline wastewater treatment.

Waterborne Urinary Tract Infections: Have We Overlooked an Important Source of Exposure?

The presence of intestinal pathogenic Escherichia coli in drinking water is well recognized as a risk for diarrhea. The role of drinking water in extraintestinal infections caused by E. coli-such as urinary tract infections (UTIs)-remains poorly understood. Urinary tract infections are a leading cause of outpatient infections globally, with a lifetime incidence of 50-60% in adult women. We reviewed the scientific literature on the occurrence of uropathogenic E. coli (UPEC) in water supplies to determine whether the waterborne route may be an important, overlooked, source of UPEC. A limited number of studies have assessed whether UPEC isolates are present in drinking water supplies, but no studies have measured whether their presence in water may increase UPEC colonization or the risk of UTIs in humans. Given the prevalence of drinking water supplies contaminated with E. coli across the globe, efforts should be made to characterize UTI-related risks associated with drinking water, as well as other pathways of exposure.