Search

Wheat grains are susceptible to contamination with various natural mycotoxins including regulated and emerging mycotoxins. This study surveyed the natural presence of regulated mycotoxins, such as deoxynivalenol (DON) and zearalenone (ZEN), and emerging mycotoxins such as beauvericin (BEA), enniatins (ENNs such as ENA, ENA1, ENB, ENB1) and Alternaria mycotoxins (i.e., alternariol monomethyl ether (AME), alternariol (AOH), tenuazonic acid (TeA), tentoxin (TEN), and altenuene (ALT)) in wheat grains randomly collected from eight provinces across China in 2021. The results revealed that each wheat grain sample was detected with at least one type of mycotoxin. The detection rates of these mycotoxins ranged from 7.1% to 100%, with the average occurrence level ranging from 1.11 to 921.8 µg/kg. DON and TeA were the predominant mycotoxins with respect to both prevalence and concentration. Approximately 99.7% of samples were found to contain more than one toxin, and the co-occurrence of ten toxins (DON + ZEN + ENA + ENA1 + ENB + ENB1 + AME + AOH + TeA + TEN) was the most frequently detected combination. The dietary exposure to different mycotoxins among Chinese consumers aged 4–70 years was as follows: 0.592–0.992 µg/kg b.w./day for DON, 0.007–0.012 µg/kg b.w./day for ZEN, 0.0003–0.007 µg/kg b.w./day for BEA and ENNs, 0.223–0.373 µg/kg b.w./day for TeA, and 0.025–0.041 µg/kg b.w./day for TEN, which were lower than the health-based guidance values for each mycotoxin, with the corresponding hazard quotient (HQ) being far lower than 1, implying a tolerable health risk for Chinese consumers. However, the estimated dietary exposure to AME and AOH was in the range of 0.003–0.007 µg/kg b.w./day, exceeding the Threshold of Toxicological Concern (TTC) value of 0.0025 µg/kg b.w./day, demonstrating potential dietary risks for Chinese consumers. Therefore, developing practical control and management strategies is essential for controlling mycotoxins contamination in the agricultural systems, thereby ensuring public health. [ABSTRACT FROM AUTHOR]

[Display omitted] • First multi-mycotoxin screening in samples randomly collected from an infant food company. • Multiple mycotoxins were detected in processed infant foods and related raw materials. • DON and TeA exhibited notably higher presence in processed infant foods and related raw materials. • Dietary exposure to AME, AOH, and TeA for infants and young children should be concerned. This study evaluated muti-mycotoxins in 199 samples including processed infant foods and raw materials collected randomly from an infant food company and assessed their role in dietary exposure in infants and young children via probabilistic risk assessment. Approximately 79.6 % (74/93) of the processed infant foods and 65.1 % (69/106) of the raw materials were contaminated by mycotoxins, with a mean occurrence level of 3.66–321.8 µg/kg. Deoxynivalenol (DON) and tenuazonic acid (TeA) were the more prevalent mycotoxins detected, based on their higher frequencies and levels across samples. Co-occurrence of more than two mycotoxins was detected in 61.3 % (57/93) of the processed infant foods and 53.8 % (57/106) of the raw materials. Wheat flour and derived products (e.g., infant noodles and infant biscuits) were contaminated with higher contamination levels and a greater variety of mycotoxins than other samples (e.g., infant cereal and rice grains). The estimated daily exposure to OTA, DON, ZEN, and TEN was lower than the corresponding reference health-based guidance values, indicating acceptable health risks. However, the estimated dietary exposure to alternariol monomethyl ether (AME), alternariol (AOH), and tenuazonic acid (TeA) exceeded the corresponding thresholds of toxicological concern values, indicating potential dietary intake risks. Among the various samples, cereals and cereal-based infant foods emerged as the primary contributors to mycotoxin exposure. Further research is advised to address the uncertainties surrounding the toxicity associated with emerging Alternaria mycotoxins and to conduct cumulative risk assessments concerning multiple mycotoxin exposure in infants and young children. [ABSTRACT FROM AUTHOR]

Deoxynivalenol (DON) and emerging Alternaria toxins often co-occur in cereal-based products, but the current risk assessment is commonly conducted for only one type of mycotoxin at a time. Compared to adults, infants and young children are more susceptible to mycotoxins through food consumption, especially with cereal-based food products which are the main source of exposure. This study aimed to perform a probabilistic risk assessment of combined exposure to DON and three major Alternaria toxins, namely including alternariol monomethyl ether (AME), alternariol (AOH), and tenuazonic acid (TeA) through consumption of cereal-based foods for Chinese infants and young children. A total of 872 cereal-based food products were randomly collected and tested for the occurrence of DON and three major Alternaria toxins. The results on mycotoxin occurrence showed the DON, TeA, AOH, and AME was detected in 56.4%, 47.5%, 7.5%, and 5.7% of the samples, respectively. Co-contamination of various mycotoxins was observed in 39.9% of the analyzed samples. A preliminary cumulative risk assessment using the models of hazard index (HI) and combined margin of exposure (MoET) was performed on DON and Alternaria toxins that were present in cereal-based food products for infants and young children in China for the first time. The results showed that only 0.2% and 1.5%, respectively, of individuals exceeded the corresponding reference value for DON and TeA, indicating a low health risk. However, in the case of AME and AOH, the proportion of individuals exceeding the reference value was 24.1% and 33.5%, respectively, indicating the potential health risks. In the cumulative risk assessment of AME and AOH, both HI and MoET values indicated a more serious risk than that related to individual exposure. Further research is necessary to reduce the uncertainties that are associated with the toxicities of the Alternaria toxins and cumulative risk assessment methods. [ABSTRACT FROM AUTHOR]

Chlorine disinfectants have been widely used in the poultry supply chain but this exposure can also result in the development of bacterial tolerance to chlorine and this is often linked to antibiotic cross-resistance. The objectives of this study were to investigate sodium hypochlorite (NaClO) tolerance of Salmonella isolated from poultry supply chains and evaluate cross-resistance. We collected 172 Salmonella isolates from poultry farms, slaughter houses and retail markets in China during 2019–2020. We found that S. Enteritidis, S. Kentucky, and S. Typhimurium constituted > 80% of our Salmonella isolates. Overall, 68% of Salmonella isolates were resistant to > 3 antibiotics and S. Kentucky displayed a significantly (p > 0.05) higher frequency (93.2%) of multidrug resistance than the other serovars. Tolerance to chlorine at MIC > 256 mg/L was detected in 93.6% of isolates (161/172) and tolerant isolates displayed higher decimal reduction times (D value) and less ultrastructural damage than did the suspectable strains under chlorine stress. Spearman analysis indicated significant positive correlations between chlorine tolerance (evaluated by the OD method) and antibiotic resistance (p < 0.05) to ceftiofur, tetracycline, ciprofloxacin and florfenicol and this was most likely due to efflux pump over-expression. The most frequently detected chlorine resistance gene was qacE Δ 1 (83.1%, n = 143) and we found a positive correlation between its presence and MIC levels (r = 0.66, p < 0.0001). Besides, we found weak correlations between chlorine-tolerance and antibiotic resistance genes. Our study indicated that chlorine disinfectants most likely played an important role in the emergence of chlorine tolerance and spread of antibiotic resistance and therefore does not completely control the risk of food-borne disease. The issue of disinfectant resistance should be examined in more detail at the level of the poultry production chain. [ABSTRACT FROM AUTHOR]

The natural occurrence of mycotoxins like Alternaria mycotoxins in food commodities is concerning in terms of health risks for humans. Currently, detailed investigations of Alternaria mycotoxins, such as alternariol (AOH), alternariol methyl ether (AME), tenuazonic acid (TeA), tentoxin (TEN), and altenuene (ALT) in food commodities marketed through e-commerce stores in China remains scarce. In addition, not many studies have focused on the associated dietary risk of these mycotoxins. This study conducted a survey (486 samples) for five Alternaria mycotoxins using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) methods. Among five Alternaria mycotoxins, TeA had the highest occurrence rate (51.0%) and concentration (average concentration of 40.6 μg/kg) in food commodities, followed by TEN, AOH, AME, and ALT. Millet and tomato products were contaminated with higher levels of TeA than other types of food commodities. The combination of TeA + TEN and AME + TeA + TEN were the predominant two contamination patterns detected in cereal and fruit products. Chronic dietary exposures to Alternaria mycotoxins were performed by the threshold of toxicological concern (TTC) approach. The mean and 95th percentile chronic dietary exposures to AOH and AME indicated different risk levels for consumers in China, with the highest exposure observed in the 2–7 years group, indicating potential dietary health concern. The mean chronic dietary exposures to TeA and ALT did not indicate a risk for the consumers, but the exposure to TeA through cereal product consumption exceeded the TTC value in the 2–12 years group at 95th percentile evaluation. Therefore, strategies should be continuously adopted to decrease or eliminate the occurrence of Alternaria mycotoxins in food commodities in order to reduce the dietary risks for humans. • Alternaria toxins screened in food samples marketed through e-ecommerce stores. • About 60.3% (293/486) of samples were contaminated with Alternaria toxins. • Co-occurrence Alternaria toxins was detected in 36.8% (179/486) of food samples. • Dietary exposures to Alternaria toxins indicated different risk levels for consumers. [ABSTRACT FROM AUTHOR]

This study aims to investigate the occurrence of aflatoxin B1 (AFB1) in total mixed rations (TMR) and aflatoxin M1 (AFM1) in raw and commercial milk in northern China during winter season. A total of 22 feed samples, as well as the corresponding 84 raw milk and 69 commercial milk samples were randomly collected from northwest, northeast and north areas of China from November 2019 to January 2020. High performance liquid chromatography and enzyme linked immunosorbent assay method were applied to detect AFB1 and AFM1. All samples presented AFB1 (30–370 ng/L) and AFM1 (10–430 ng/L) levels under the legal limit of China for raw milk (10 μg/L) and commercial milk (500 ng/L). While 31.8% of TMRs and 34.5% of raw milk samples exceeded the European Union (EU) legal limit for AFM1 in raw milk (5 μg/L) and commercial milk (50 ng/L). Compared with the samples from northeast and north areas of China with the similar AFB1 concentration, samples from northwest area of China exhibited higher AFM1 level (mean = 130 ng/L), thus presenting a higher transfer ratio from AFB1 to AFM1. A Linear relationship was observed between AFB1 in TMRs and AFM1 in raw milk. In conclusion, all samples from northern China presented AFB1 and AFM1 levels under Chinese legal limit and only about 30% of the tested samples exceeded the EU legal limit. However, the aflatoxin contamination in northwest area of China should be paid more attention to due to the high AFM1 levels and high variance in milk samples. • Aflatoxin B1 and aflatoxin M1 contamination in northern China is under legal limit of China. • More attention should be paid to aflatoxin contamination in Northwest of China. • Linear regression was obtained between AFB1 of TMRs and AFM1 of raw milk. [ABSTRACT FROM AUTHOR]

Simple Summary: Quail is an economically important type of poultry, valued for its high meat quality and abundant egg nutrition. It is also an important laboratory research animal, widely used in developmental biology and toxicology tests. Since the gut microbiota plays a vital role in the host's growth and health, we investigated the microbiota inhabiting the duodenum, jejunum, ileum, cecum, and colorectum of quail in the present study, using 16S rRNA gene sequencing and qPCR. The concentrations of short-chain fatty acids (SCFAs) were evaluated using gas chromatography. We found that the microbiota in the cecum was different from other intestinal sections and the enriched inhabitants of SCFA-producing bacterial genera made cecum the core locations of SCFA production in quail. The results of this study will provide fundamental data for further quail microbiology and functional studies. Quail is raised throughout China for egg and meat production. To deeply understand the gastrointestinal microbial composition and metabolites of quail, the present study characterized the microbiota inhabiting five intestinal locations of eight-week-old quail using 16S rRNA gene sequencing and qPCR, and evaluated the concentrations of short-chain fatty acids (SCFAs) in each individual location using gas chromatography. The results showed that Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, and Deferribacteres were the five most abundant phyla in the intestinal tract of quail. Firmicutes was largely dominant (>95%) in the small intestine, whereas Bacteroidetes increased significantly in the cecum (19.19%) and colorectum (8.09%). At the genus level, Lactobacillus was predominant in almost all sections (>50%) except in the cecum (7.26%), where Megamonas, Faecalibacterium, and Bacteroides were dominant. qPCR data indicated that the population sizes of both the total bacteria and proportions of the Firmicutes, Bacteroidetes, and Bacteroides group increased going from the proximal toward the distal end of the intestine in quail. The SCFA-producing bacterial genera Bacteroides, Faecalibacterium, Alistipes, Blautia, Parabacteroides, and Clostridium were of higher richness in the cecum and colorectum, where, accordingly, more SCFAs were produced. These findings will be helpful for the future study of quail microbiology, as well as its relationship with productive performance and health. [ABSTRACT FROM AUTHOR]

Alternaria species are invasive fungi that infect fruits and vegetables and produce Alternaria toxins resulting in loss of commodity values and harmful effects on human health. To establish a reliable analytical method for Alternaria toxins in fruits, vegetables and their derivatives (e.g., fruit and vegetable juices, purees and jams; dried fruit and vegetables; fruit and vegetable powders), a QuEChERS extraction method was developed and validated for the determination of most reported Alternaria toxins (alternariol monomethyl ether [AME], alternariol [AOH], tentoxin [TEN], tenuazonic acid [TeA], and altenuene [ALT]). The limits of quantitation (LOQ) of the target analytes in food matrices were 1.0–5.0 μg/kg. The extraction recoveries were 73.0%–120%, with good repeatability (<12.9%) and within-laboratory repeatability (<14.7%). The developed method was applied to 270 fruits, vegetables, and their derivatives randomly collected from the market in China. Approximately 45.2% of the samples were contaminated with varying levels of Alternaria toxins. The lowest incidence of contamination by Alternaria toxins was detected in fruits and vegetables (3.6%), and the highest incidence was found in fruit and vegetable powders (60.6%). TeA exhibited the highest detection frequency (22.6%) and the highest level of occurrence level (639 μg/kg) among the tested samples, followed by AOH (14.1%), ALT (11.9%), AME (4.4%), and TEN (3.3%). Furthermore, the simultaneous co-presence of two to five Alternaria toxins was detected in 13.7% of the analyzed samples. The combination of AOH + TeA was the most predominant, accounting for 4.8% of samples. This study developed a reliable and sensitive analytical method and provided representative occurrence data to support the assessment of emerging mycotoxins, especially Alternaria toxins, in fruit and vegetable products. • A QuEChERs extraction method developed for Alternaria toxins determination. • Five Alternaria toxins surveyed in 270 fruit and vegetable products. • High incidence and levels of Alternaria toxins found in fruit and vegetable powders. • Puree and juice samples detected various types of co-occurrences of Alternaria toxins. [ABSTRACT FROM AUTHOR]

Emerging Alternaria and Fusarium mycotoxins are increasingly becoming a public health concern due to the frequent contamination of various food commodities with these mycotoxins, posing potential health risks to humans. This study developed QuEChERS extraction method coupled with LC–MS/MS for simultaneous quantification of alternariol monomethyl ether (AME), alternariol (AOH), tentoxin (TEN), tenuazonic acid (TeA), altenuene (ALT), enniatins (ENNs) A, A1, B, and B1, and beauvericin (BEA) in tomatoes and derived tomato products. The validated method was successfully applied for a survey of 194 tomatoes and derived tomato products. Overall, one or more mycotoxins were detected in 58.8% of the samples, 100% of tomato powders, 100% of canned tomatoes, 89.6% of tomato sauces, 82.1% of ketchups, 46.7% of tomato juices, and 20% of dried tomatoes, with no mycotoxins detected in fresh tomatoes. Various mycotoxins were detected at relatively higher contamination levels in tomato powders than in other tomato products. TeA, the most predominant mycotoxin, was detected in 56.7% of the samples with an occurrence level of up to 7,985 μg/kg. Approximately 39.2% of positive samples presented the co-occurrence of more than one mycotoxins, and AME + AOH + TeA was the most frequently detected combination. This study is the first to perform the deterministic risk assessment for children and adults on Alternaria and Fusarium mycotoxins that are present in tomatoes and derived tomato products in China. The results showed that the average and 95th percentile dietary exposures to these mycotoxins, especially to AME and AOH, in children might be higher than those in adults by a factor of approximately 2. The estimation of exposure to either Alternaria mycotoxins or Fusarium mycotoxins indicated that the presence of Alternaria and Fusarium mycotoxins in derived tomato products might be a health concern, especially among children and the populations consuming a high amount of these products. However, no firm conclusion could be drawn due to the lack of relevant in vivo toxicity data. This study serves as a useful reference for individuals and food safety authorities concerning mycotoxin contamination in food commodities. • Methods for emerging toxins determination in various tomato products were developed. • About 58.8% (114/194) of tomato-based products were contaminated with emerging toxins. • Co-occurrence of various emerging toxins was evident in 39.2% (76/194) of samples. • Dietary exposures to Alternaria and Fusarium toxins varied among children and adults. [ABSTRACT FROM AUTHOR]

Chlorine and its derivatives, such as sodium hypochlorite (NaClO) and chlorine dioxide, are frequently employed as disinfectants throughout the pork supply chain in China. Nevertheless, the extensive use of NaClO has the potential to cause the creation of 'chlorine-tolerant bacteria' and accelerate the evolution of antibiotic resistance. This study evaluated the efficacy of NaClO disinfection by examining alterations in the microbiome and resistome of a pork wholesale market (PWM), and bacteria isolation and analysis were performed to validate the findings. As expected, the taxonomic composition s of bacteria was significantly different before and after disinfection. Notably, Salmonella enterica (S. enterica) , Salmonella bongori (S. bongori), Escherichia coli (E. coli), Klebsiella pneumoniae (K. pneumoniae) , and Pseudomonas aeruginosa (P. aeruginosa) were observed on all surfaces, indicating that the application of NaClO disinfection treatment in PWM environments for pathogenic bacteria is limited. Correlations were identified between antibiotic resistance genes (ARGs) associated with aminoglycosides (aph(3′')-I, aph(6′)-I), quinolone (qnrB, abaQ), polymyxin (arnA, mcr-4) and disinfectant resistance genes (emrA/BD , mdtA/B/C/E/F). Furthermore, correlations were found between risk Rank I ARGs associated with aminoglycoside (aph(3′)-I), tetracycline (tetH), beta_lactam (TEM-171), and disinfectant resistance genes (mdtB/C/E/F, emrA, acrB, qacG). Importantly, we found that Acinetobacter and Salmonella were the main hosts of disinfectant resistance genes. The resistance mechanisms of the ARGs identified in PWM were dominated by antibiotic deactivation (38.7%), antibiotic efflux (27.2%), and antibiotic target protection (14.4%). The proportion of genes encoding efflux pumps in the PWM resistome increased after disinfection. Microbial cultures demonstrated that the traits of microbial contamination and antibiotic resistane were consistent with those observed by metagenomic sequencing. This study highlights the possibility of cross-resistance between NaClO disinfectants and antibiotics, which should not be ignored. [Display omitted] • Taxonomic compositions of bacterial were changed before and after disinfection. • The application of NaClO disinfection treatment on pathogenic bacteria was limited. • The Acinetobacter and Salmonella were main hosts of disinfectant resistance genes. • Significant correlations were found between ARGs and disinfectant resistance genes. • The proportion of genes encoding efflux pumps increased in the PMW disinfection. [ABSTRACT FROM AUTHOR]

Deoxynivalenol (DON), a mycotoxin produced by various Fusarium species, was analyzed in 200 cereal-based food products collected from e-commerce stores in China. Optimized methods using immunoaffinity column (IAC) clean-up coupled with UV detection were applied. DON was detected in 87.5% (12.5–1920.4 μg/kg) of samples, and 10.5% of tested samples exceeded the legal limit for DON in China (1000 μg/kg). DON was found in 100% of whole wheat flour (51.6–1308.9 μg/kg), Chinese steamed bread (54.5–845.4 μg/kg), and biscuit (40.9–1920.4 μg/kg), samples, and in 85.3% of all-purpose flour (12.5–1285.4 μg/kg), 73.3% of maize flour (26.4–138.2 μg/kg), and 60.0% of oat flake samples (16.8–243.6 μg/kg), with 426.0, 293.0, 419.2, 455.7, 55.4, and 44.0 μg/kg, respectively, representing the mean levels in these products. A chronic intake assessment indicated that estimated daily intake (EDI) of DON through the consumption of wheat flour was 1.0–3.8 and 3.1–11.3 times that of the Provisional Maximum Tolerable Daily Intake (PMTDI) of 1.0 μg/kg body weight/day for adults and children, respectively, at different levels. The EDIs of DON consumed through wheat flour-derived products (Chinese steamed bread and biscuits) for children was 1.7–12.7 times those of the PMTDI at different levels, whereas the EDIs obtained through consumption of maize flour and oat flakes were 0.2 times lower than those of the PMTDI for both adults and children. In a dietary exposure assessment, the acute hazard indexes (aHI) for adults and children were above 100% of Acute Reference Dose (ARfD) of 8.0 μg/kg body weight/day) through the consumption of wheat flour, Chinese steamed bread, and biscuits, and the aHIs were only 16.4% (31.2%) and 5.1% (8.3%) of ARfD for adults (children). Among the cereal-based food products analyzed, both chronic (long-term) and acute (short-term) dietary exposure assessments for DON consumption by adults and children indicated that wheat flour (all-purpose flour and whole wheat flour), Chinese steamed bread, and biscuits have become sources of potential health hazards in the human diet in China. The risk associated with DON contamination in maize flour and oat flakes should also not be ignored. [ABSTRACT FROM AUTHOR]

The distribution of deoxynivalenol (DON) and its derivatives 3-acetyldeoxynivalenol (3-Ac-DON) and 15-acetyldeoxynivalenol (15-Ac-DON) throughout the wheat processing chain were systemically evaluated by one-to-one corresponding studies of the whole processing chain. DON and its derivatives were determined by liquid chromatography-mass spectrometry (LC-MS/MS) in wheat grains and corresponding wheat bran, wheat flour, and semi-finished and finished wheat flour-based products. This investigation showed that wheat grain processing to wheat flour significantly decreased the levels of DON by approximately 52.7%-68.2%. Wheat flour processing of wheat flour-based products decreased the DON concentration by approximately 7.0%-70.6%. Among the processing methods, biscuit making showed the largest reduction (70.6%). The co-occurrence frequency of DON with low levels of 3-Ac-DON and 15-Ac-DON was significantly greater in wheat grains and wheat bran than in wheat flour. For wheat flour-based products, only the distribution pattern of 3-Ac-DON was observable in processed wheat flour products prepared using grains heavily contaminated with DON. In China, to the best of our knowledge, the processing factors (PFs) of DON in wheat flour and wheat flour-based products were systematically evaluated for the first time. The average PF of DON was 0.35 for wheat flour and the average PFs were 0.37-0.84 for wheat flour-based products, with biscuits having the smallest PF (0.37), indicating DON significantly decreasing in biscuit making. Furthermore, dietary exposure assessment of DON indicated an acceptable overall health risk in Chinese consumers, with the highest exposure being observed in infants and young children. This study provides important references for classified management of DON limits in wheat and its various products in China., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

General Purpose: To present research investigating the incidence of and risk factors associated with intraoperative pressure injury in patients undergoing neurologic surgery at Xiangya Hospital, Central South University in China., Target Audience: This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and registered nurses with an interest in skin and wound care., Learning Objectives/outcomes: After participating in this educational activity, the participant will:1. Identify the incidence of intraoperative pressure injuries (PIs) in patients undergoing neurologic surgery at Xiangya Hospital, Central South University in China.2. Describe risk factors for intraoperative PI.3. Outline strategies to help mitigate intraoperative PI risk., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Occludin is an important component of tight junction proteins and has been extensively studied in animals such as mice, chickens, geese, and pigs. As one of the most important waterfowl species in China, Muscovy duck (Cairina moschata) is an important economic animal for meat. However, research on the occludin gene in Muscovy duck is lacking. In the present study, Muscovy duck occludin cDNA was cloned for the first time. The length of the cDNA was 1,699 bp, and it showed a high sequence similarity with the Anser cygnoides domesticus and Gallus gallus occludin genes. The occludin gene was differentially expressed in the tissues of healthy ducks. The highest and lowest expressions of occludin were observed in the crop and the spleen, respectively. After the oral administration of Clostridium butyricum (CB), the occludin expression in the ileum of 7-day-old Muscovy ducks was significantly upregulated and subsequently showed a decreasing trend in 14-day-old Muscovy ducks. Under the early intervention of CB, no significant difference was observed in the occludin expression of cecum between the control and CB group. Collectively, these results suggest that CB plays an important role in regulating the expression of the occludin gene in Muscovy ducks, and adding CB in feed may maintain the intestinal barrier of ducks by regulating the expression of occludin., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

In this work, the occurrence of 34 common antibiotic (15 sulfonamides and 19 quinolones) residues were evaluated in 236 ready-to-eat duck eggs (salted and preserved duck eggs) marketed through e-commerce stores by ultra-performance liquid chromatography coupled to tandem mass spectrometry, and subsequent dietary risk assessments for Chinese consumers were conducted. Among violated positives in duck egg samples, 11 analytes were found including sulfamethazine, sulfaquinoxaline, sulfamethoxazole, sulfadiazine, sulfamonomethoxine, ciprofloxacin, enrofloxacin, ofloxacin, flumequine, sarafloxacin, and nalidixic acid. A higher number of antibiotics were detected in salted duck eggs (five sulfonamides and six quinolones) than in preserved duck eggs (one sulfonamide and two quinolones). The maximum contamination of sulfonamides and quniolones was 448.0 µg/kg (sulfaquinoxaline) and 563.7 µg/kg (enrofloxacin) in salted duck eggs, respectively. Dietary exposure was evaluated through the estimated daily intake (EDI) of risky antibiotics (sulfamethazine, ciprofloxacin, and enrofloxacin) and hazard quotients (HQs). The results showed that EDIs and HQs were in the range of 0.0004 to 0.0099 µg/kg bw/day and 0.0009 to 0.1594%, respectively. The risk was low since HQs obtained were less than 100%. However, a special attention should be paid to ready-to-eat duck egg products high percentile consumers with the prosperity of e-commerce market in China. PRACTICAL APPLICATION: The present analytical method could be used for multiresidue determination of antibiotics in ready-to-eat duck eggs, and dietary risk assessments of risky antibiotics provided a support for the work of regulatory bodies to conduct surveillance programs regarding food safety evaluation of ready-to-eat foods., (© 2021 Institute of Food Technologists®.)

In this study, we evaluated the prevalence of Salmonella in retail raw chickens in Shaanxi Province, China, on a monthly basis. In addition, we studied the antibiotic susceptibility, serotype, and genotype of Salmonella isolates and explored their relationships with sampling time, location, market type, and chicken type. The results showed that Salmonella was more prevalent in chickens sampled during the spring and summer than during the autumn and winter. Thirty-nine serotypes were identified from 406 Salmonella isolates, of which Salmonella typhimurium (16.7%) was the most prevalent. Other prevalent serotypes included S. thompson (12.8%), S. essen (9.1%), S. infantis (6.9%), S. rissen (5.7%), and S. enteritidis (5.4%). Approximately 71.4% of the 406 isolates were resistant to 3 or more antibiotics, 11.8% to 12 or more, and 1.7% to all 14 antibiotics tested. The most frequently detected resistance was to trimethoprim/sulfamethoxazole (82.0%), followed by nalidixic acid (71.9%) and tetracycline (59.4%). The frequencies of resistance to ampicillin, chloramphenicol, and amoxicillin/clavulanic acid were moderately high (∼50% each). Resistance to kanamycin, ceftiofur, streptomycin, gentamicin, and ciprofloxacin was less common (<40% each). Serotype distribution and antibiotic susceptibility of Salmonella isolates were related to sampling time, location, chicken type, and market type. Isolates recovered from the same sampling time, market type, location, and chicken type commonly exhibited identical or similar genotypes and antibiotic resistance profiles. However, DNA profiles and antibiotic resistance phenotypes of isolates within some serotypes were diverse. Our results revealed that multiple Salmonella subtypes with antibiotic resistance were prevalent in retail raw chickens in Shaanxi Province. Our study findings provide information for developing preventive measures against contamination of retail foods with Salmonella., (Copyright © 2020. Published by Elsevier Inc.)

The aim of this study was to determine the presence and characteristics of Escherichia coli in ready-to-eat (RTE) foods. A total of 300 RTE foods samples were collected in Shaanxi Province, People's Republic of China: 50 samples of cooked meat, 165 samples of vegetable salad, 50 samples of cold noodles, and 35 samples of salted boiled peanuts. All samples were collected during summer (in July to October) 2011 and 2012 and surveyed for the presence of E. coli . E. coli isolates recovered were classified by phylogenetic typing using a PCR assay. The presence of Shiga toxin genes 1 (stx 1 ) and 2 (stx 2 ) was determined for these E. coli isolates by PCR, and all isolates were analyzed for antimicrobial susceptibility and the presence of class 1 integrons. Overall, 267 (89.0%) RTE food samples were positive for E. coli : 49 cold noodle, 46 cooked meat, 150 salad vegetable, and 22 salted boiled peanut samples. Of the 267 E. coli isolates, 73.0% belong to phylogenetic group A, 12.4% to group B1, 6.4% to group B2, and 8.2% to group D. All isolates were negative for both Shiga toxin genes. Among the isolates, 74.2% were resistant to at least one antimicrobial agent, and 17.6% were resistant to three or more antimicrobial agents. Resistance to ampicillin (75.6% of isolates) and tetracycline (73.1% of isolates) was most frequently detected; 26.2% of E. coli isolates and 68.8% of multidrug-resistant E. coli isolates were positive for class 1 integrons. All isolates were sensitive to amikacin. Our findings indicate that RTE foods in Shaanxi were commonly contaminated with antibiotic-resistant E. coli , which may pose a risk for consumer health and for transmission of antibiotic resistance. Future research is warranted to track the contamination sources and develop appropriate steps that should be taken by government, industry, and retailers to reduce microbial contamination in RTE foods.