Pig Slaughterhouses Research Articles

Acclimatation of Microbial Biomass to Effluents From a Swine Slaughterhouse in Batch Reactors

Objective: To evaluate the acclimatization of microbial biomass in sequential reactors to optimize the treatment of wastewater from pig slaughterhouses. Theoretical framework: The meat industry generates highly contaminated wastewater. Biological treatments, such as aerobic and anaerobic systems, are more efficient and sustainable than physicochemical ones. Materials and methods: Industrial effluents were collected in a pig slaughterhouse and then characterized. The microbial biomass was collected from the same slaughterhouse and was subjected to an acclimatization process in a sequential batch reactor. Results and discussion: The results showed that the wastewater from the pig slaughterhouse had high levels of BOD, COD and suspended solids, exceeding the limits established by local regulations. During the acclimatization process, the microbial biomass demonstrated a gradual improvement in its COD removal capacity, reaching efficiencies greater than 70%. The positive correlation observed between volumetric organic load and organic matter removal efficiency indicates that acclimated biomass has a greater capacity to treat effluents with high levels of organic load. Research implications: Biomass acclimatization is essential to improve the efficiency of biological treatment in slaughterhouse effluents, reducing its environmental impact and the need for costly treatments. Value/originality: This study proposes a more sustainable and efficient solution for the treatment of slaughterhouse wastewater, highlighting the importance of biomass acclimatization.

Genomic diversity of Salmonella Typhimurium and its monophasic variant in pig and pork production in France.

Salmonellosis is a leading cause of bacterial infection in humans and animals around the world. This study provides a snapshot of the genomic diversity of one of the most prevalent Salmonella serovars (Salmonella Typhimurium and Salmonella 4,[5],12:i:-) circulating on French pig farms between 2013 and 2021. We investigated the link between geographical and genomic diversity. The analyses revealed little diversity of the strains, suggesting that one or two clones are spreading within French pig herds. We also in silico screened genetic elements that could explain the prevalence of these strains among farmed pigs and in the slaughterhouse environment. Finally, the comparison with isolates from other countries highlighted the genomic specificity of these two French sequence type 34 clones. This work provides new insights into the dynamics of S. Typhimurium and S. 4,[5],12:i:- sampled from pig herds and slaughterhouses in France, thus laying the foundations for future analyses.

Escherichia coli Occurrence and Antimicrobial Resistance in a Swine Slaughtering Process.

The swine production chain can be a reservoir of antimicrobial-resistant Escherichia coli, which transfers resistance genes to other bacteria, serving as an important biomarker in the One Health approach. This study aimed to identify the frequency and antimicrobial resistance profile of E. coli in the swine production chain, assess the presence of extended-spectrum beta-lactamases (ESBL), and compare resistance profiles across different sample types. A total of 622 samples of swine carcasses from various points of the slaughter process (n = 400), swine feces (n = 100), commercial cuts (n = 45), environment (n = 67), and feces from employees (n = 10) of a pig slaughterhouse certified by the Federal Inspection Service, located in São Paulo state, Brazil, were collected. A total of 1260 E. coli isolates were obtained from the samples, with 73.6% of the samples testing positive. The agar disk diffusion test was performed with 10 different classes of antimicrobials. To confirm the production of ESBLs, the isolates were submitted to a double-disk synergism test using cefotaxime, ceftazidime, and amoxicillin with clavulanic acid. Of the total isolates, 80.71% were multidrug resistant. All ESBL-producing isolates were multidrug resistant and resistant to amoxicillin, tetracycline, and chloramphenicol. Isolates from human feces samples had less chance of being multidrug resistant than samples from other sources. The diversity of resistance profiles was verified in the samples, not clustering according to the sources, except for human feces isolates that clustered, evidencing lower antimicrobial resistance variability of these samples. Antimicrobial resistance is significantly present in the pork production chain, necessitating a comprehensive multidisciplinary approach to effectively mitigate risks within the One Health framework.

ELIME-IMS hybrid assay for Salmonella detection in swine mesenteric lymph nodes at slaughterhouse

Salmonella contamination in pig slaughterhouses is linked to infection rate on farms. Accurate diagnosis in heavy pigs relies on isolating pathogens from the gut wall or lymph nodes. A key technique is Immunocapture using Magnetic Beads (IMS), which purifies target bacteria from Salmonella enrichment broths. This is followed by an Enzyme-Linked Immunomagnetic Electrochemical (ELIME) assay for rapid detection. In our study, we developed an ELIME-IMS hybrid assay to detect Salmonella in swine mesenteric lymph nodes (MNL), involving a clean-up with N-acetylcysteine and centrifugation. Detection limits for S. Typhimurium and S. Derby were estimated at 2.80 and 3.52 Log CFU/ml, respectively. We analysed 103 MNL samples from a northern Italy slaughterhouse. Additionally, we examined 15 carcass swabs. Both the ELIME assay and the IMS-based culture method showed strong agreement with the ISO 6579–1:2017 method, especially after 20 h of enrichment (89.47% concordance). The clean-up step significantly influenced the results, as samples processed without it showed higher variability. A logistic regression model indicated high classification accuracy for negative samples using ELIME values. The ELIME-IMS assay facilitates rapid Salmonella screening and isolation in swine mesenteric lymph nodes.

Assessing antimicrobial resistance profiles of Salmonella enterica in the pork production system.

Introduction. Salmonella enterica is a significant enteric pathogen affecting human and livestock health. Pork production is a common source of Salmonella contamination, with emerging multidrug resistance (MDR) posing a global health threat.Gap statement. Salmonella contamination and antimicrobial resistance (AMR) profiles in the pig production chain are underreported.Aim. To investigate the prevalence of S. enterica in the pig production chain and characterise their AMR profiles.Methodology. We collected 485 samples from pig farms, a standard pig abattoir and retail markets in Patthalung and Songkhla provinces in southern Thailand. Antimicrobial susceptibility testing was performed on these samples, and AMR profiles were determined.Results. S. enterica was detected in 68.67% of farm samples, 45.95% of abattoir samples and 50.67% of retail market samples. Analysis of 264 isolates, representing 18 serotypes, identified S. enterica serotype Rissen as the most prevalent. The predominant resistance phenotypes included ampicillin (AMP, 91.29%), tetracycline (TET, 88.26%) and streptomycin (STR, 84.47%). Over 80% of isolates showed resistance to three or more antimicrobial classes, indicating MDR. The AMP-STR-TET resistance pattern was found in nearly 70% of all MDR isolates across the production chain.Conclusions. The high prevalence of MDR is consistent with extensive antimicrobial use in the livestock sector. The presence of extensively resistant S. enterica highlights the urgent need for antimicrobial stewardship. Strengthening preventive strategies and control measures is crucial to mitigate the risk of MDR Salmonella spreading from farm to fork.

Multi-drug resistant (MDR) and extended-spectrum β-lactamase (ESBL) producing Escherichia coli isolated from slaughtered pigs and slaughterhouse workers in Yaoundé, Cameroon

Antimicrobial resistance (AMR) in the food chain remains a global public health concern for both humans and animals. This study aimed to determine the prevalence, resistance profiles, and clonal relatedness of multidrug-resistant (MDR) and extended-spectrum β-lactamases- producing Escherichia coli (ESBL-Ec) isolated from slaughtered pigs and slaughterhouse workers in Yaoundé, Cameroon.A cross-sectional study was conducted over four months, from February to May 2023 in two selected pig's slaughterhouse markets in Yaoundé. Rectal swabs were collected from 375 pigs at four time points and pooled per three according to gender, origin, and abattoirs leading to 125 pooled samples. Seven faecal samples from 60 contacted exposed workers were collected. Samples were cultured on CHROMagar™ ESBL medium, dark pink to reddish colonies were considered E. coli. Resistance genes including blaCTX-M, blaSHV and blaTEM were detected using the polymerase chain reaction (PCR) while ERIC-PCR was used to assess the genetic relatedness between isolates.The prevalence of ESBL-Ec was elevated among exposed workers (71.4 %; n = 5/7) and pigs (70.4 %; n = 88/125). Overall, ESBL-Ec exhibited high resistance to cefuroxime (100 %, n = 105/105), cefotaxime (100 %, n = 105/105), amoxicillin-clavulanic acid (98.1 %, n = 103/105), cefixime (92.4 %, n = 97/105), tetracycline (86.7 %, n = 91/105) and sulfamethoxazole-trimethoprim (81.9 %, n = 86/105). However, these isolates showed good susceptibility to gentamicin (3.8 %, n = 4/105), chloramphenicol (8.6 %, n = 9/105), and fosfomycin (14.3 %, n = 15/105). All human isolates and 75.8 % (n = 75/99) of pig isolates were multi-drug resistant. The blaCTX-M was the most prevalent resistance gene among exposed workers (100 %, n = 6/6) and pigs (80.8 %, n = 80/99) followed by blaTEM (33.3 % each). High clonal relatedness of ESBL-Ec strains was observed among pig and human isolates across slaughterhouses.This study showed that the gastrointestinal tract of pigs might be an important reservoir of MDR and ESBL-Ec in Yaoundé, Cameroon and these resistant bacteria might be circulating between sources, especially humans. Heightening awareness on appropriate antibiotic use in humans and animals as well as implementing stringent biosecurity and food safety measures are imperative to prevent the emergence and spread of AMR in the country.

Comparative analysis of Salmonella contamination in pork slaughtering facilities: Implications for food safety

Salmonella is a major cause of global gastroenteritis, with pig-based products being significant sources. The Hazard Analysis Critical Control Points (HACCP) standard ensures food safety by identifying Salmonella contamination dynamics and improving control strategies. A study in Thailand found that pork in HACCP-certified slaughterhouses had significantly reduced Salmonella contamination and antimicrobial resistance (AMR) compared to in non-HACCP facilities. However, both types of slaughterhouses still experience Salmonella contamination during the slaughtering process, with limited information available on contamination sources and critical steps. The current study compared Salmonella distribution and AMR profiles in two Thai pig slaughterhouses, one of which implemented HACCP. A total of 570 samples, including feces, carcass swabs, and environmental samples, were cultured for Salmonella and investigated for AMR. The overall prevalence was 24.7%, being significantly lower at the HACCP-compliant slaughterhouse 1 (S1, 13.7%) compared to the non-compliant slaughterhouse 2 (S2, 41.2%) (P = 0.03). Slaughterhouse-specific Salmonella prevalence varied across slaughtering steps, with S2 showing high contamination rates in carcasses post-final washing, persisting until post-cutting. Additionally, specific strains were found in various locations, including feces, carcasses, workers' hands, cutting boards, and knives before and during operations. Conversely, carcasses post-final washing in S1 had the lowest contamination. Real-Time PCR identified higher Salmonella contamination and a greater copy number in S2-cutting carcasses compared to in S1. Overall, 42.6% of isolates were multidrug-resistant, showing strong resistance to ampicillin and tetracycline, while 8.51% produced extended-spectrum beta-lactamase (ESBL). It is evident that continuous monitoring and control measures are crucial to mitigate contamination and antibiotic resistance in foodborne pathogens such as Salmonella. The current study confirms that adherence to HACCP in slaughterhouses significantly reduces Salmonella in pork products. However, contamination levels rose notably post-cutting in both HACCP and non-HACCP facilities, with equipment, other carcasses, and workers' hands acting as sources of contamination. Rigorous monitoring during cutting processes is essential to identify and mitigate contamination sources, thereby improving food safety in meat processing facilities.

Clonal spread of blaNDM-1-carrying Salmonella enterica serovar Typhimurium clone ST34 and wide spread of IncHI2/ST3-blaNDM-5 plasmid in China.

To characterize blaNDM-carrying Salmonella recovered from a pig slaughterhouse. In this study, 46 environment samples were collected from a slaughterhouse in China, and screened for carbapenem-resistant Enterobacterales. WGS, antimicrobial susceptibility testing and conjugation experiments were carried out to identify the isolates' resistance phenotypes and genetic characteristics. The phylogenetic relatedness of the Salmonella isolates obtained in this study and Salmonella (ST34 and ST29) in GenBank was determined. Two ST34 Salmonella Typhimurium and one ST29 Salmonella Stanley, recovered from three environmental samples (6.52%), were positive for blaNDM-1 and blaNDM-5, respectively. The two ST34 S. Typhimurium strains exhibited a close relationship (10-36 SNPs) with two human-derived blaNDM-1-bearing isolates from China (Hong Kong and Guangxi Province) and two blaNDM-negative ST34 Salmonella strains from the UK. The blaNDM-1 genes were located on IncHI2/ST3 plasmids. The capture of blaNDM-1 by the IncHI2/ST3 plasmid seems to be due to homologous recombination mediated by circular structures, as the genetic arrangements of the blaNDM-1 gene contain two IS26 elements of the same orientation. The blaNDM-5 gene was also carried by the IncHI2/ST3 plasmid, which shares highly similar structures with other blaNDM-5-bearing IncHI2/ST3 plasmids from other sources (fish, chicken, duck, human). This is the first report of a blaNDM-5-carrying IncHI2/ST3 plasmid in Salmonella. The clonal spread of NDM-1-producing ST34 S. Typhimurium across human and animal-associated environments, and the widespread dissemination of epidemic blaNDM-5-carrying IncHI2/ST3 plasmids among Enterobacteriaceae in China indicate the potential of further dissemination of blaNDM among Salmonella, which poses a threat to public health.

The hidden threat: Comprehensive assessment of antibiotic and disinfectant resistance in commercial pig slaughterhouses

The presence of antibiotic resistance genes (ARGs), disinfectant resistance genes (DRGs), and pathogens in animal food processing environments (FAPE) poses a significant risk to human health. However, knowledge of the contamination and risk profiles of a typical commercial pig slaughterhouse with periodic disinfectant applications is limited. By creating the overall metagenomics-based behavior and risk profiles of ARGs, DRGs, and microbiomes in a nine-section pig slaughterhouse, an important FAPE in China. A total of 454 ARGs and 84 DRGs were detected in the slaughterhouse with resistance genes for aminoglycosides and quaternary ammonium compounds, respectively. The entire slaughtering chain is a hotspot for pathogens, including 83 human pathogenic bacteria (HPB), with 47 core HPB. In addition, 68 high-risk ARGs were significantly correlated with 55 HPB, 30 of which were recognized as potential bacteria co-resistant to antibiotics and disinfectants, confirm a three-fold risk of ARGs, DRGs, and pathogens prevailing throughout the chain. Pre-slaughter pig house (PSPH) was the major risk source for ARGs, DRGs, and HPB. Moreover, 75 Escherichia coli and 47 Proteus mirabilis isolates showed sensitivity to potassium monopersulfate and sodium hypochlorite, suggesting that slaughterhouses should use such related disinfectants. By using whole genome multi-locus sequence typing and single nucleotide polymorphism analyses, genetically closely related bacteria were identified across distinct slaughter sections, suggesting bacterial transmission across the slaughter chain. Overall, this study underscores the critical role of the PSPH section as a major source of HPB, ARGs, and DRGs contamination in commercial pig slaughterhouses. Moreover, it highlights the importance of addressing clonal transmission and cross-contamination of antibiotic- and disinfectant-resistant bacteria within and between slaughter sections. These issues are primarily attributed to the microbial load carried by animals before slaughter, carcass handling, and content exposure during visceral treatment. Our findings provide valuable insights for One Health-oriented slaughterhouse management practices.

An Integrated Analysis of Abattoir Lung Lesion Scores and Antimicrobial Use in Italian Heavy Pig Finishing Farms.

Respiratory diseases significantly affect intensive pig finishing farms, causing production losses and increased antimicrobial use (AMU). Lesion scoring at slaughter has been recognized as a beneficial practice to evaluate herd management. The integrated analysis of abattoir lesion scores and AMU data could improve decision-making by providing feedback to veterinarians and farmers on the effectiveness of antimicrobial treatments, thus rationalizing their use. This study compared lung and pleural lesion scores collected at Italian pig slaughterhouses with on-farm AMU, estimated through a treatment index per 100 days (TI100). Overall, 24,752 pig carcasses, belonging to 236 batches from 113 finishing farms, were inspected. Bronchopneumonia and chronic pleuritis were detected in 55% and 48% of the examined pigs, respectively. Antimicrobials were administered in 97% of the farms during the six months prior to slaughter (median TI100 = 5.2), notwithstanding compliance with the mandatory withdrawal period. EMA category B (critical) antimicrobials were administered in 15.2% of cases (median TI100 = 0.06). The lung score was not associated with the total AMU, but significant, positive associations were found with the past use of critical antimicrobials (p = 0.041) and macrolides (p = 0.044). This result highlights the potential of abattoir lung lesion monitoring to rationalize antimicrobial stewardship efforts, contributing to AMU reduction.

Effect of reusing heat-treated scalding water on carcass hygiene in industrial pig slaughterhouse

To save water resources, scalding water used in a pig slaughterhouse was treated at 80 °C for 3 h and reused the next slaughtering day. Water samples were collected before and after the treatment and at the end of the slaughtering day to evaluate the microbial counts. Aerobic colony counts were not significantly different in water samples between treated and clean water at the beginning of the slaughtering day (2.59 and 2.61 log CFU/mL; p = 0.93), and no Enterobacteriaceae and Salmonella spp. were ever detected in the water. Furthermore, the microbial counts of pig carcass after water treatment, sampled immediately after scalding, was compared with those obtained by replacing it with clean water. The aerobic colony count was 5.60 and 5.83 log CFU/400 cm2 at the start of the slaughtering day and 5.72 and 5.49 log CFU/400 cm2 at the end of the slaughtering day, in control and reused water respectively. Higher aerobic colony counts were detected at the beginning of the slaughtering days in treated groups and at the end of the slaughtering days in control groups. Salmonella was detected in a few carcasses, independently for treated and control groups, and no relation with water treatment could be found.

A network analysis of the local pig supply chain in a repeated outbreak area of human streptococcosis in Thailand.

The present study employed a network analysis approach to scrutinize a pig supply chain in a repeated outbreak province for human streptococcosis in Thailand and identified important actors that should be focused on for tailoring appropriate interventions. Nakhon Sawan province was chosen as the study site as the cases of human streptococcosis have been consecutively reported since 2014, with the number of cases ranging from 21 to 63. A questionnaire survey was used to collect data from actors along the pig supply chain, including pig farms, slaughterhouses, pork sellers, restaurants and customers. A one-mode-directed network was then constructed. Degree and betweenness centrality values were measured. We found that the supply chain of pork products comprised 314 nodes and 296 directed ties. A retailer got the highest overall degree, out-degree and betweenness centrality values at 35, 34, and 65.3, respectively. For in-degree centrality, the highest was identified in a customer at 9. Interestingly, this customer bought pork products from nine different mobile groceries. Both public health and veterinary authorities should extend their surveillance activities to cover all actors in the supply chain to strengthen overall disease prevention and control for streptococcosis.

Treatment of effluents from pig slaughterhouses by removing nitrogen and phosphorus using sequential biological reactors

El objetivo de esta investigación fue evaluar la eficiencia de un tratamiento biológico en efluentes provenientes de la matanza de cerdos usando reactores por carga secuencial. Se implementaron tres tiempos de ciclo operacional (TCO) de 8, 12 y 16 horas, una secuencia anaerobia-aerobia-anóxica, y dos tiempos de retención celular (TRC), 15 y 25 días, realizando un total de seis tratamientos en reactores a escala laboratorio. Los parámetros fisicoquímicos medidos fueron la demanda química de oxígeno total (DQOT), nitrógeno amoniacal, nitritos, nitratos, ortofosfatos, fósforo total, pH y alcalinidad, al inicio, final de cada fase de la secuencia y salida del reactor, por cada tratamiento evaluado. De acuerdo a los resultados obtenidos, los porcentajes de remoción de DQOT estuvieron entre 82,0 y 86,9%, mientras que, para el nitrógeno y fósforo, las remociones se encontraron entre 46,7 y 71,6%, y 38,1 y 54,5%, respectivamente. La velocidad de nitrificación tuvo una buena correspondencia con la remoción de nitrógeno amoniacal, la mayor velocidad se obtuvo con un TRC de 25 d, lo que indica que la actividad de la biomasa nitrificante fue alta. Para todos los tratamientos evaluados se observó la liberación de ortofosfatos durante la fase anaeróbica y su consumo durante la fase aeróbica en la secuencia operacional. El tratamiento biológico en el reactor que permitió obtener los mayores porcentajes de remoción simultánea de materia orgánica y nutrientes fue el realizado con un TCO de 16 h y un TRC de 25 días.

Investigation of Salmonella, hepatitis E virus (HEV) and viral indicators of fecal contamination in four Italian pig slaughterhouses, 2021–2022

In the pork production chain, the control at slaughterhouse aims to ensure safe food thanks to proper hygienic conditions during all steps of the slaughtering. Salmonella is one of the main foodborne pathogens in the EU causing a great number of human cases, and pigs also contribute to its spreading. Pig is the main reservoir of the zoonotic hepatitis E virus (HEV) that can be present in liver, bile, feces and even rarely in blood and muscle. The aim of this study was to assess the presence of both Salmonella and HEV in several points of the slaughtering chain, including pig trucks. Other viruses hosted in the gut flora of pigs and shed in feces were also assayed (porcine adenovirus PAdV, rotavirus, norovirus, and mammalian orthoreovirus MRV). Torque teno sus virus (TTSuV) present in both feces, liver and blood was also considered. Four Italian pig abattoirs were sampled in 12 critical points, 5 of which were the outer surface of carcasses before processing. HEV and rotavirus (RVA) were not detected. Norovirus was detected once. Salmonella was detected in two of the 4 abattoirs: in the two lairage pens, in the site of evisceration and on one carcass, indicating the presence of Salmonella if carcass is improper handled. The sampling sites positive for Salmonella were also positive for PAdV. MRV was detected in 10 swabs, from only two abattoirs, mainly in outer surface of carcasses. TTSuV was also detected in all abattoirs. Our study has revealed a diverse group of viruses, each serving as indicator of either fecal (NoV, RVA, PAdV, MRV) or blood contamination (TTSuV). TTSuV could be relevant as blood contamination indicators, crucial for viruses with a viremic stage, such as HEV. The simultaneous presence of PAdV with Salmonella is relevant, suggesting PAdV as a promising indicator for fecal contamination for both bacterial and viruses. In conclusion, even in the absence of HEV, the widespread presence of Salmonella at various points in the chain, underscores the need for vigilant monitoring and mitigation strategies which could be achieved by testing not only bacteria indicators as expected by current regulation, but also some viruses (PAdV, TTSuV, MRV) which could represent other sources of fecal contamination.

Coagulation/Flocculation of Slaughterhouse Effluent Using Pac and Tanfloc as Coagulants

Objective: In this context, this research aimed to evaluate the influence of different types of coagulants, one inorganic and one natural (PAC and Tanfloc), in the treatment of an effluent from a pig slaughterhouse. Method/design/approach: Both coagulants were prepared in aqueous solution at the time of the test, 1% (v/v) for PAC and 0.5% (m/v) for Tanfloc. To assess the effect of the coagulants on the effluent, coagulation/flocculation tests were carried out using the jar-test apparatus. The dosages evaluated for both coagulants were 50, 100, 150, 200, 250 and 300 mg/L. The parameters analyzed were color and turbidity. Results and conclusion: According to the results of the statistical analysis, the optimum dosages obtained for both coagulants was 250 mg/L. With these dosages, removal of the parameters analyzed was observed (> 94% for turbidity and > 85% for color) with residuals (< 40 NTU for turbidity and < 400 uH for color), showing better results at this optimum dosage when Tanfloc is used as a coagulant. Implications of the research: The growing awareness that effluent treatment is of fundamental importance to public health and environmental pollution control has led us to look for low-cost alternatives to treat these effluents, using a vegetable organic coagulant based on tannin as an alternative to aluminum polychloride (PAC). Originality/value: Due to the growing need for low-cost, easily accessible treatments that do not require large areas, physical-chemical treatment of slaughterhouse effluent can be used as a pre-treatment, with the use of alternative coagulants, being a viable way to reduce organic matter for subsequent biological treatment, or in some cases replace the biological process.

Coagulation/Floculation Of Slaughter Effluent Using Moringa Oleifera Lam as A Coagulant

Objective: In view of the growing need for low-cost, easily accessible alternative wastewater treatments, this study aimed to evaluate the influence of a natural product (Moringa oleifera lam), when used as a coagulant, on the removal of turbidity and color from a pig slaughterhouse effluent. Method/design/approach: The coagulant was prepared in saline solution (NaCl - 1M) and saline solution (KCl - 1M), all the coagulant solutions were prepared at the time of the test. In order to assess the effect of the coagulant on the effluent, coagulation/flocculation tests were carried out using the Jar- test apparatus, evaluating the effects of dosages of 200, 500, 1000, 1500 and 2000 mg/L of Moringa in saline solution (NaCl and KCl). The parameters analyzed were color and turbidity. Results and conclusion: According to the results of the statistical analysis, the optimum dosages obtained for the coagulants Moringa NaCl and Moringa KCl were 1000 and 1500 mg/L, respectively. With these dosages, removal of 63.9% for turbidity and 56.3% for color was observed when using NaCl saline solution and removal of 57.4% for turbidity and 45.2% for color when using the coagulant in KCl saline solution. Implications of the research: The main implication of the study is a proposal to evaluate the efficiency of the coagulation/flocculation/decantation process of pig slaughterhouse effluent, using natural coagulants, in the removal of organic matter. Due to the many problems caused by the use of chemical coagulants, such as aluminum sulfate and aluminum polychloride, which are used worldwide, there is a great demand for an alternative coagulant that is mainly natural. Originality/value: The study seeks to contribute to improving the management of water resources, in terms of local management. The use of natural coagulants, produced locally and at a low cost, can alleviate the problems linked to the discharge of untreated wastewater into receiving water bodies and the consumption of non-potable water.

Prevalence and Genetic Characterization of Methicillin-Resistant Staphylococcus aureus Isolated from Pigs in Japan.

We investigated the prevalence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in pig slaughterhouses from 2018 to 2022 in Japan and the isolates were examined for antimicrobial susceptibility and genetic characteristics by whole-genome analysis. Although the positive LA-MRSA rates on farms (29.6%) and samples (9.9%) in 2022 in Japan remained lower than those observed in European countries exhibiting extremely high rates of confirmed human LA-MRSA infections, these rates showed a gradually increasing trend over five years. The ST398/t034 strain was predominant, followed by ST5/t002, and differences were identified between ST398 and ST5 in terms of antimicrobial susceptibility and the resistance genes carried. Notably, LA-MRSA possessed resistance genes toward many antimicrobial classes, with 91.4% of the ST398 strains harboring zinc resistance genes. These findings indicate that the co-selection pressure associated with multidrug and zinc resistance may have contributed markedly to LA-MRSA persistence. SNP analysis revealed that ST398 and ST5 of swine origin were classified into a different cluster of MRSA from humans, showing the same ST in Japan and lacking the immune evasion genes (scn, sak, or chp). Although swine-origin LA-MRSA is currently unlikely to spread to humans and become a problem in current clinical practice, preventing its dissemination requires using antimicrobials prudently, limiting zinc utilization to the minimum required nutrient, and practicing fundamental hygiene measures.

Prevalence of work-related musculoskeletal disorders and ergonomic risk assessment among production workers of pig slaughterhouse in the town municipality of Ang Thong, Thailand

Introduction: Work-related musculoskeletal disorders (WMSDs) are a significant health concern among workers, especially in the meat processing industry. Their impacts have been well documented and reported on numerous occasions. The study aimed to determine the prevalence of WMSDs and the ergonomic assessment of exposure to their risk factors. Methods: This cross-sectional study was conducted in a pig slaughterhouse in the town municipality of Ang Thong, Thailand. Data were collected from April to July 2021 from 108 participants who answered a questionnaire. The descriptive questionnaire for WMSDs was adapted from the Standardized Nordic Questionnaire in Thai and the Bureau of Occupational and Environmental Diseases, Department of Disease Control of Thailand. Ten individuals received an ergonomic assessment of their exposure to risk factors using the Rapid Entire Body Assessment (REBA) method. Results: According to the study, 94.4% of participants working in pig slaughterhouse production reported experiencing the prevalence of WMSDs in the last seven days. Additionally, 93.5% of workers reported experiencing the prevalence of these disorders within the past 12 months. It has been observed that 29.6% of participants experience higher pain levels in their hands, while 25.9% experience it in their wrists, respectively. Based on the results of an ergonomic risk assessment using the REBA method, the half-cutting operator position presents a moderate level of risk. Conclusion: The study revealed that most of the workers at the pig slaughterhouse had to use their hands and arms to apply repeated pressure consistently. The occurrence rates of WMSDs within the last seven days and 12 months were highest in the hands or wrists, followed by the upper arms and shoulders. Therefore, it is crucial to implement ergonomic measures to minimize the risk factors for WMSDs among production workers in pig slaughterhouses.

The prevalence of Staphylococcus aureus and the emergence of livestock-associated MRSA CC398 in pig production in eastern China.

Livestock-associated Staphylococcus aureus (LA-MRSA) has been of increasing concern due to its potential risk to humans. This study investigated the prevalence of MRSA in pig production in Eastern China and determined the genomic characteristics of pig-associated MRSA isolates by whole-genome sequencing (WGS). A total of 1,318 samples were collected from pig farms and pig slaughterhouses, and 150 S. aureus were identified, including 63 MRSA isolates and 87 MSSA isolates. MRSA was detected in all pig farms and pig slaughterhouses. The antimicrobial susceptibility test revealed that all MRSA isolates were multidrug-resistant. The WGS and MLST analysis demonstrated that 56 MRSA isolates belonged to clonal complex (CC) 398, and seven MRSA isolates belonged to CC9. All LA-MRSA isolates were absent of phiSa3 phage containing immune evasion cluster (IEC) and possessed an intact hlb gene. In addition, genes associated with Panton-Valentine leukocidin, typically indicative of human adaptation, were not detected. The analysis of antibiotic resistance genes (ARGs) demonstrated that all MRSA isolates contained multiple ARGs. All MRSA isolates had Plthe mecA gene and at least one tetracycline resistance gene. Both tetM and tetK were detected in all MRSA CC398 isolates, while tetL was detected in all MRSA CC9 isolates. The phenicol resistance gene fexA was detected in 51 MRSA isolates, while the linezolid resistance gene cfr was detected in 60 MRSA isolates. The emergence of LA-MRSA CC398 in four pig farms and one slaughterhouse in this study indicates the spread of this clonal complex in the pig production sector in Eastern China. Further investigations are required to understand the potential transmission routes of LA-MRSA CC398 within the pork production chain in China and to assess the potential risks to humans.

Isolation and Characterization of Extended-Spectrum β-Lactamase Producing Escherichia coli from Pig Farms and Slaughterhouse.

Extended-spectrum β-lactamase (ESBL) producing Escherichia coli represents a formidable challenge in the field of microbiology and public health due to its resistance to commonly used antibiotics. These strains pose a serious threat to human and animal health, underscoring the urgency of comprehensive research and surveillance. The ongoing investigation seeks ESBL producing E. coli strains from pig farms and slaughterhouses in West Bengal and Assam, India. A total of 309 samples were collected: nasal swabs (25), rectal swabs (25) from healthy pigs, pig pen soil (45), faeces (55), slaughterhouse effluents (115), and cleaning water (44). In these samples, 154 tested positive for E. coli, indicating a 49.8% prevalence. Among 154 E. coli isolates, 23 (14.9%) produced ESBLs, sourced from pig rectal swabs (7.1%), faeces (10.7%), slaughterhouse effluents (26.1%), and cleaning water (11.7%). Significantly, 4 ESBL E. coli isolates (6.6%) exclusively emerged from pig slaughterhouse effluents, displaying imipenem-resistant properties. The majority of ESBL E. coli primarily produced CTX-M and CMY, with consistent genetic markers bla CTX-M (100%) and bla CMY (82.6%). Remarkably, 2 (8.6%) of 17 ESBL E. coli isolates from pig slaughterhouse effluents carried the genetic marker bla NDM1. These findings stress implementing thorough surveillance in pig farms and local slaughterhouses. This proactive approach is crucial to identify ESBL E. coli strains, enhancing public health protection.