Mapping and Functional Dissection of the Rumpless Trait in Piao Chicken Identifies a Causal Loss of Function Mutation in the Novel Gene Rum.

Rumpless chickens exhibit an abnormality in their tail development. The genetics and biology of this trait has been studied for decades to illustrate a broad variation in both the types of inheritance and the severity in the developmental defects of the tail. In this study, we created a backcross pedigree by intercrossing Piao (rumpless) with Xianju (normal) to investigate the genetic mechanisms and molecular basis of the rumpless trait in Piao chicken. Through genome-wide association and linkage analyses, the candidate region was fine-mapped to 798.5 kb (chromosome 2: 86.9 to 87.7 Mb). Whole-genome sequencing analyses identified a single variant, a 4.2 kb deletion, which was completely associated with the rumpless phenotype. Explorations of the expression data identified a novel causative gene, Rum, that produced a long, intronless transcript across the deletion. The expression of Rum is embryo-specific, and it regulates the expression of MSGN1, a key factor in regulating T-box transcription factors required for mesoderm formation and differentiation. These results provide genetic and molecular experimental evidence for a novel mechanism regulating tail development in chicken and report the likely causal mutation for the tail abnormity in the Piao chicken. The novel regulatory gene, Rum, will, due to its role in fundamental embryo development, be of interest for further explorations of a potential role in tail and skeletal development also in other vertebrates.

A Breathable Fibrous Membrane with Coaxially Heterogeneous Conductive Networks toward Personal Thermal Management and Electromagnetic Interference Shielding.

The expeditious growth of wearable electronic devices has boomed the development of versatile smart textiles for personal health-related applications. In practice, integrated high-performance systems still face challenges of compromised breathability, high cost, and complicated manufacturing processes. Herein, a breathable fibrous membrane with dual-driven heating and electromagnetic interference (EMI) shielding performance is developed through a facile process of electrospinning followed by targeted conformal deposition. The approach constructs a robust hierarchically coaxial heterostructure consisting of elastic polymers as supportive "core" and dual-conductive components of polypyrrole and copper sulfide (CuS) nanosheets as continuous "sheath" at the fiber level. The CuS nanosheets with metal-like electrical conductivity demonstrate the promising potential to substitute the expensive conductive nano-materials with a complex fabricating process. The as-prepared fibrous membrane exhibits high electrical conductivity (70.38 S cm-1), exceptional active heating effects, including solar heating (saturation temperature of 69.7 °C at 1 sun) and Joule heating (75.2 °C at 2.9 V), and impressive EMI shielding performance (50.11 dB in the X-band), coupled with favorable air permeability (161.4 mm s-1 at 200 Pa) and efficient water vapor transmittance (118.9 g m-2 h). This work opens up a new avenue to fabricate versatile wearable devices for personal thermal management and health protection.

Multi-bioinspired hierarchical integrated hydrogel for passive fog harvesting and solar-driven seawater desalination.

In recent years, with the outbreak and epidemic of the novel coronavirus in the world, how to obtain clean water from the limited resources has become an urgent issue of concern to all mankind. Atmospheric water harvesting technology and solar-driven interfacial evaporation technology have shown great potential in seeking clean and sustainable water resources. Here, inspired by a variety of organisms in nature, a multi-functional hydrogel matrix composed of polyvinyl alcohol (PVA), sodium alginate (SA) cross-linked by borax as well as doped with zeolitic imidazolate framework material 67 (ZIF-67) and graphene owning macro/micro/nano hierarchical structure has successfully fabricated for producing clean water. The hydrogel not only can reach the average water harvesting ratio up to 22.44 g g-1 under the condition of fog flow after 5 h, but also be capable of desorbing the harvested water with water release efficiency of 1.67 kg m-2 h-1 under 1 sun. In addition to excellent performance in passive fog harvesting, the evaporation rate over 1.89 kg m-2 h-1 is attained under 1 sun on natural seawater during long-term. This hydrogel indicates its potential in producing clean water resources in multiple scenarios in different dry or wet states, and which holds great promise for flexible electronic materials and sustainable sewage or wastewater treatment applications.

The Love and Hate Relationship between T5SS and Other Secretion Systems in Bacteria.

Bacteria have existed on Earth for billions of years, exhibiting ubiquity and involvement in various biological activities. To ensure survival, bacteria usually release and secrete effector proteins to acquire nutrients and compete with other microorganisms for living space during long-term evolution. Consequently, bacteria have developed a range of secretion systems, which are complex macromolecular transport machines responsible for transporting proteins across the bacterial cell membranes. Among them, one particular secretion system that stands out from the rest is the type V secretion system (T5SS), known as the "autotransporter". Bacterial activities mediated by T5SS include adherence to host cells or the extracellular matrix, invasion of host cells, immune evasion and serum resistance, contact-dependent growth inhibition, cytotoxicity, intracellular flow, protease activity, autoaggregation, and biofilm formation. In a bacterial body, it is not enough to rely on T5SS alone; in most cases, T5SS cooperates with other secretion systems to carry out bacterial life activities, but regardless of how good the relationship is, there is friction between the secretion systems. T5SS and T1SS/T2SS/T3SS/T6SS all play a synergistic role in the pathogenic processes of bacteria, such as nutrient acquisition, pathogenicity enhancement, and immune modulation, but T5SS indirectly inhibits the function of T4SS. This could be considered a love-hate relationship between secretion systems. This paper uses the systematic literature review methodology to review 117 journal articles published within the period from 1995 to 2024, which are all available from the PubMed, Web of Science, and Scopus databases and aim to elucidate the link between T5SS and other secretion systems, providing clues for future prevention and control of bacterial diseases.

Riemerella anatipestifer infection affects intestinal barrier structure and immune reactions in the duck caecum.

Riemerella anatipestifer (RA) infection causes high mortality and poor feed conversion, leading to great economic losses to the duck industry. This study investigated the effects of RA on the intestinal morphology and immune response of ducks. Histological examination showed that RA infection caused intestinal injury, including significantly reduced mucosal thickness on days 2, 3 and 5, significantly reduced villus height on days 1, 2, 3 and 5 (P < 0.05) and significantly reduced villus height to crypt depth ratios on days 2, 3, 5 and 9 of RA infection (P < 0.05). The expression of intestinal mucosal layer construction-associated genes and tight junction genes was significantly altered on at least one time point (day 1, 2, 3, 5, 9 or 14) after RA infection. Quantitative real-time polymerase chain reaction revealed that RA infection affected intestinal mucosal immune function. The genes encoding TLR4 (toll like receptor-4), TRAF6 (TNF receptor-associated factor 6), MYD88 (myeloid differentiation factor 88), IFN-γ (interferon-γ), IL (interleukin)-4 and IL-8 were significantly upregulated on day 2 of RA infection. Taken together, these results indicate that RA infection negatively affects intestinal barrier function in ducks due to impaired mucosal and villus-crypt structure and alters the mRNA expression of mucous layer construction-, intestinal tight junction-, and intestinal mucosal immunity-related genes.

Fimbriae and related receptors for Salmonella Enteritidis.

Infection with Salmonella Enteritidis (SE) is one of the main causes for food- and water-borne diseases, and is a major concern to public health for both humans and animals worldwide. Some fimbrial antigens expressed by SE strains have been described and characterized, containing SEF14, SEF17, SEF21, long polar fimbriae and plasmid-encoded fimbriae, they play a role in bacterial survival in the host or external environment. However, their functions remain to be well elucidated, with the initial attachment and binding for fimbriae-mediated SE infections only minimally understood. Meanwhile, host-pathogen interactions provide insights into receptor modulation of the host innate immune system. Therefore, to well understand the pathogenicity of SE bacteria and to comprehend the host response to infection, the host cell-SE interactions need to be characterized. This review describes SE fimbriae receptors with an emphasis on the interaction between the receptor and SE fimbriae.

Small non-coding RNA STnc640 regulates expression of fimA fimbrial gene and virulence of Salmonella enterica serovar Enteritidis.

BACKGROUND: Small non-coding RNAs (sRNAs) regulate bacterial gene expression at the post-transcriptional level. STnc640 is a type of sRNA that was identified in Salmonella Typhimurium. RESULTS: In this study, STnc640 in Salmonella Enteritidis was confirmed to be an Hfq-dependent sRNA. TargetRNA software analysis showed that fimbrial genes fimA and bcfA were likely to be the target genes of STnc640. To investigate the target mRNAs and function of STnc640 in pathogenicity, we constructed the deletion mutant strain 50336△stnc640 and the complemented strain 50336△stnc640/pstnc640 in Salmonella Enteritidis 50336. The RT-qPCR results showed that the mRNA level of fimA was decreased, while bcfA was unchanged in 50336△stnc640 compared with that in the wild type (WT) strain. The adhesion ability of 50336△stnc640 to Caco-2 cells was increased compared to the 50336 WT strain. The virulence of 50336△stnc640 was enhanced in a one-day-old chicken model of S. Enteritidis disease as determined by quantifying the 50% lethal dose (LD50) of the bacterial strains. CONCLUSIONS: The results demonstrate that STnc640 contributes to the virulence of Salmonella Enteritidis.

Sensitive and Label-Free Fluorescent Detection of Transcription Factors Based on DNA-Ag Nanoclusters Molecular Beacons and Exonuclease III-Assisted Signal Amplification.

Transcription factors (TFs) regulate gene expression by binding to regulatory regions, and their dysregulation is involved in numerous diseases. Thus, they are therapeutic targets and potential diagnostic markers. However, widely used methods for TFs detection are either cumbersome or costly. Herein, we first applied DNA-Ag nanoclusters molecular beacons (AgMBs) in TFs analysis and designed an assay based on the switchable fluorescence of AgMBs. In the absence of TFs, a single-stranded DNA functioned as a reporter is released from a double-stranded DNA probe (referred as dsTFs probe) under exonuclease III (Exo III) digestion. Then, the reporter triggers downstream Exo III-assisted signal amplification by continuously consuming the guanine-rich enhancer sequences in AgMBs, resulting in significant fluorescent decrease eventually. Conversely, the presence of TFs protects the dsTFs probe from digestion and blocks the downstream reaction to keep a highly fluorescent state. To testify this rationale, we utilized nuclear factor-kappa B p50 (NF-κB p50) as a model TFs. Owing to the amplification strategy, this method exhibited high sensitivity toward NF-κB p50 with a limit of detection of 10 pM, and a broad linear range from 30 pM to 1.5 nM. Furthermore, this method could detect multiple TFs in human colon cancer DLD-1 cells and reflect the variation in their cellular levels after stimulation. Finally, by conducting an inhibition assay we revealed the potential of this method for screening TFs-targeted drugs and calculating the IC50 of corresponding inhibitors.

Highly Drug-Resistant Salmonella enterica Serovar Indiana Clinical Isolates Recovered from Broilers and Poultry Workers with Diarrhea in China.

Highly drug-resistant Salmonella enterica serovar Indiana became the most common serovar in broilers with diarrhea in China over the course of this study (15% in 2010 to 70% in 2014). While most S. Indiana isolates (87%, 384/440) were resistant to 13 to 16 of the 16 antibiotics tested, 89% of non-S. Indiana isolates (528/595) were resistant to 0 to 6 antibiotics. Class 1 integrons and IncHI2-type plasmids were detected in all S. Indiana isolates, but only in 39% and 1% of non-S. Indiana isolates.

Adjuvant Treatment with Yupingfeng Formula for Recurrent Respiratory Tract Infections in Children: A Meta-analysis of Randomized Controlled Trials.

This meta-analysis aimed to evaluate the immunomodulating function of Yupingfeng Formula (YPFF) in children with recurrent respiratory tract infections (RRTIs). The PubMed, EMBASE, Cochrane Library, CNKI and WanFang databases were searched for randomized controlled trials comparing with and without YPFF for RRTIs in children. Twelve trials with 1236 patients were identified. Adjuvant treatment with YPFF significantly increased serum levels of IgA (weighted mean difference [WMD] 0.33 mg/mL; 95% confidence interval [CI] 0.20 to 0.45), IgG (WMD 1.36 mg/mL; 95% CI 1.06 to 1.65), IgM (WMD 0.16 mg/mL; 95% CI 0.02 to 0.31), and CD3(+) T-lymphocytes (WMD 10.16%; 95% CI 4.62 to 15.69) but not CD4(+) T-lymphocytes (WMD 3.16%; 95% CI -0.27 to 6.59) and CD8(+) T-lymphocytes (WMD -0.84%; 95% CI -2.50 to 0.81). YPFF also reduced the frequency of RRTIs (WMD -3.80 times; 95% CI -4.86 to -2.74) and increased total effective rates of symptom improvement (risk ratio: 1.44; 95% CI 1.19 to 1.75). Adjuvant treatment with YPFF could improve total clinical effective rate and decrease the frequency of respiratory tract infections in children with RRTIs. The beneficial effects of YPFF may be correlated to its immunomodulating action. More well-designed trials with larger sample sizes are needed to evaluate its efficacy and safety. Copyright © 2016 John Wiley & Sons, Ltd.

Loop-Mediated Isothermal Amplification of the sefA Gene for Rapid Detection of Salmonella Enteritidis and Salmonella Gallinarum in Chickens.

Salmonella spp. pose a threat to both human and animal health, with more than 2600 serovars having been reported to date. Salmonella serovars are usually identified by slide agglutination tests, which are labor intensive and time consuming. In an attempt to develop a more rapid screening method for the major poultry Salmonella serovars, we developed a loop-mediated isothermal amplification (LAMP) assay, which directly detected the sefA gene, a fimbrial operon gene existing in several specific serovars of Salmonella enterica including the major poultry serovars, namely Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) and Salmonella enterica serovar Gallinarum (Salmonella Gallinarum). With the 177 bacterial strains we tested, positive reactions were only observed with 85 strains of serovar Salmonella Enteritidis and Salmonella Gallinarum. The detection limit of the LAMP assay was 4 CFU/reaction with genomic DNAs of Salmonella Enteritidis (ATCC 13076) from pure culture and 400 CFU/ reaction with DNA extracted from spiked chicken feces. The LAMP assay was more sensitive than conventional culture, especially without enrichment, in detecting Salmonella Enteritidis (CMCC 50041) in the spiked fecal samples. The results show the sefA LAMP method is a rapid, sensitive, specific, and practical method for directly detection of Salmonella Enteritidis and Salmonella Gallinarum in chickens. The sefA LAMP assay can potentially serve as new on-site diagnostics in the poultry industry.

One-Step Identification of Five Prominent Chicken Salmonella Serovars and Biotypes.

Based on bacterial genomic data, we developed a one-step multiplex PCR assay to identify Salmonella and simultaneously differentiate the two invasive avian-adapted S. enterica serovar Gallinarum biotypes Gallinarum and Pullorum, and the most frequent, specific, and asymptomatic colonizers of chickens, serovars Enteritidis, Heidelberg, and Kentucky.

Prevalence and fimbrial genotype distribution of poultry Salmonella isolates in China (2006 to 2012).

In this study, a total of 323 Salmonella enterica strains were isolated from 3,566 rectal swab samples of 51 poultry farms in seven regions of 12 provinces of China between 2006 and 2012. The prevalences of Salmonella sp. carriage were 12.4% in geese (66 positive/533 samples), 10.4% in turkeys (32/309), 9.8% in chickens (167/1,706), 6.8% in ducks (41/601), and 4.1% in pigeons (17/417), respectively. These isolates belonged to 20 serovars, in which the most frequent serovars were S. enterica serovar Gallinarum biovar Pullorum (herein, S. Pullorum) (55 isolates, 17.0%), S. enterica serovar Typhimurium (50 isolates, 15.5%), and S. enterica serovar Enteritidis (39 isolates, 12.1%). Overall, S. Typhimurium was the most commonly detected serovar; among the individual species, S. Pullorum was most commonly isolated from chickens, S. Enteritidis was most common in ducks, S. Typhimurium was most common in geese and pigeons, and S. enterica serovar Saintpaul was most common in turkeys. PCR determination of 20 fimbrial genes demonstrated the presence of bcfD, csgA, fimA, stdB, and sthE genes and the absence of staA and stgA genes in these isolates, and other loci were variably distributed, with frequency values ranging from 11.8 to 99.1%. These 323 Salmonella isolates were subdivided into 41 different fimbrial genotypes, and of these isolate, 285 strains (88.2%) had 12 to 14 fimbrial genes. Our findings indicated that the Salmonella isolates from different poultry species were phenotypically and genetically diverse and that some fimbrial genes are more frequently associated with serovars or serogroups.

Simple and rapid detection of Salmonella by direct PCR amplification of gene fimW.

This study established a simple method of specifically detecting Salmonella species by amplifying fimW gene, which was involved in regulating Salmonella type I fimbriae expression. A pair of primers was designed to target and discriminate the 68 Salmonella strains of 23 Salmonella serovars available to us from 12 non-Salmonella strains of five different kinds of bacteria by polymerase chain reaction (PCR) amplification. Results showed that specific DNA fragment with an expected size of 477 bp was successfully amplified from all Salmonella serovars, while no target band was detected in non-Salmonella species. The sensitivity of this PCR-amplifying system reached to 1 pg DNA chromosome and 10(2) cfu of Salmonella enteritis strain CMCC(B) 50336. The above results demonstrated the method as a simple, sensitive, and specific way for Salmonella detection.

Development of skeletal muscle and expression of myogenic regulatory factors during embryonic development in Jinding ducks (Anas platyrhynchos domestica).

The important roles of myogenic regulatory factors (MRF) in mammalian skeletal myogenesis have been well studied, but few equivalent studies have been performed in poultry. The expression pattern of MRF during the embryonic development of skeletal muscle in ducks remains unknown. In this study, we identified Myf5, Myf6, MyoD, and myogenin genes in Jinding ducks (Anas platyrhynchos domestica) and quantified their expression levels in breast muscle (BM) and leg muscle (LM) at embryonic d 13, 17, 21, 25, and 27 by real-time reverse-transcription PCR. Body weight and muscle weight show different developmental patterns. The MRF genes were expressed in both BM and LM, but with different expression patterns. The MyoD gene showed lower expression levels in BM before embryonic d 21 compared with LM, whereas the opposite pattern was found later. The higher expression level of MyoD, as well its lagged expression pattern in BM, suggest that the MyoD gene may be involved in maintaining the development of different muscles. Correlation analysis showed that myogenin gene expression levels were significantly negatively correlated with BW and muscle weight in both BM and LM (P < 0.001), and MyoD and Myf6 gene expression levels were more strongly correlated with muscle weight in LM than in BM. The results of this study provide novel evidence for MRF expression in ducks in embryonic stage- and skeletal muscle-dependent manners, and provide a foundation for understanding the molecular control of skeletal muscle growth in duck breeds.

Eggshell membrane as a novel and green platform for the preparation of highly efficient and reversible curcumin-based colorimetric sensor for the monitoring of chicken freshness.

Herein, for the very first time, we report a paper-like biomass, eggshell membrane (ESM), as a suitable platform for the fabrication of a colorimetric sensor (E-Cot). Green ethanolic extract, curcumin (CUR), was used as a sensing material to coat with the ESM. The present E-Cot effectively changed its color (yellow to red) in the real-time monitoring for chicken spoilage. The E-Cot exhibits barrier properties due to its inherent semi-permeability characteristics. Interestingly, the E-Cot showed a significant change in total color difference value (ΔE, 0 days - 0.0-39.6, after 1 day - 39.6-42.1, after 2 days - 42.1-53.6, after 3 days- 53.6-60.1, and after 4 days - 60.1-66.3, detectable by the naked eye) in the real-time monitoring for chicken freshness. In addition, the present E-Cot smart colorimetric sensor is reversible with a change in pH, and the sensor can be reused. Further, the hydrophobic nature of the E-Cot was confirmed by water contact angle analysis (WCA, contact angle of 101.21 ± 8.39). Good antibacterial, barrier, and optical properties of the present E-Cot were also found. Owing to the advantages such as green, efficient, cost-effective, biodegradable, reusable, sustainable, and simple preparation, we believe that the present E-Cot would be a more attractive candidate.

Effects of residual feed intake on the economic traits of fast-growing meat ducks.

Feed efficiency (FE) is a crucial economic indicator of meat duck production. The objective of this study was to assess the impact of residual feed intake (RFI), defined as the difference between the actual and expected feed intake based on animal's production and maintenance requirements, on the growth performance (GP), slaughter and internal organ characteristics of fast-growing meat ducks. In total, 1,300 healthy 14-day-old male fast-growing meat ducks were housed in individual cages until slaughter at the age of 35 d. The characteristics of the carcass and internal organs of 30 ducks with the highest RFI (HRFI) and the lowest RFI (LRFI) were respectively determined. RFI, the feed conversion ratio (FCR), and average day feed intake (ADFI) were significantly lower in the LRFI group than the HRFI group (P < 0.001), while there were no significant differences in marketing BW or BW gain (BWG) (P > 0.05). The thigh muscle and lean meat yields were higher, and the abdominal fat content was lower (P < 0.001) in the LRFI group, while there were no significant differences in other carcass traits between the groups (P > 0.05). The liver and gizzard yields were significantly higher (P < 0.001) in the LRFI group, while there were no significant differences (P > 0.05) in intestinal length between the groups. RFI was highly positively correlate with FCR and ADFI (P < 0.01), but negatively correlated the yields of thigh muscle, lean meat, liver, and gizzard, and positively correlated with abdominal fat content. These results indicate that selection for low RFI could improve the FE of fast-growing meat ducks without affecting the marketing BW and BWG, while increasing yields of thigh muscle and lean meat and reducing abdominal fat content. These findings offer useful insights into the biological processes that influence FE of fast-growing meat ducks.

Non-destructive strategy to extract sustainable helix and high-strength Musa core fibers for rapid water conduction and evaporation.

The reuse and development of natural waste resources is a hotspots and challenges in the research of new fiber materials and the resolution of environmental concern globally. Herein, this study aimed to develop a simple and direct manual extraction process to extract Musa core fibers (MCFs) for rapid water conduction and evaporation. Through simple processes such as ring cutting and stretching, this green and non-destructive inside-out extraction strategy enabled Musa fibers to be naturally and harmlessly degummed from natural Musa stems, with good maintenance of the fiber structure and highly helical morphology. The extracted fibers are composed of regularly and closely arranged cellulose nanofibrils in the shape of ribbon spirally arranged multi-filaments, and the single filament is about 2.65 µm. The high-purity fibers exhibit ultra-high tensile strength under a non-destructive extraction process, and the ultimate tensile strength in dry state is as high as 742.95 MPa. The tensile strength is affected by the number of fiber bundles, which shows that tensile strength and tensile modulus is higher than those of vascular bundle fibers in dry or wet condition. In addition, the MCFs membrane indicates good water conductivity, with a water absorption height of 50 mm for the sample in only 60 s. Moreover, the water evaporation rate of MCFs reaches 1.37 kg m-2 h-1 in 30 min, which shows that MCFs have excellent water conductivity and evaporation rate compared with ordinary cotton fibers. These results indicate that MCFs have great potential in replacing the use of chemical methods to extract fibers from vascular bundles, providing an effective way to achieve sustainability in quick-drying applications, as well as in the sustainable development of natural waste resources.

SEF14 fimbriae from Salmonella enteritidis play a role in pathogenitic to cell model in vitro and host in vivo.

The role of SEF14 fimbriae in virulence remains to be elucidated and in this study, we showed that sefA mutant constructed in the wild-type (WT) Salmonella enteritidis strain 50336 displayed increased invasion to IPEC-J2 cell lines and survival in mouse peritoneal macrophages, and the lethal dose 50% (LD50) in 6-week-old Balb/c mice intra-peritoneally injected with WT S. enteritidis strain decreased significantly upon deletion of sefA indicating their role in virulence. Overall, these results demonstrated that expression of sefA of SEF14 fimbriae enhances S. enteritidis adhesion to epithelial cells and survival in macrophages and contributes to S. enteritidis virulence in mice.

Antimicrobial resistance, presence of integrons and biofilm formation of Salmonella Pullorum isolates from Eastern China (1962-2010).

Three hundred and thirty-seven isolates of Salmonella Pullorum from eastern China between 1962 and 2010 were characterized for antimicrobial susceptibility (disk diffusion method), the presence of integrons (polymerase chain reaction followed by sequencing) and the ability to form biofilms (semi-quantitative adherence assay). Two hundred and fifty-eight isolates (76.6%) exhibited multiple drug resistance (MDR; resistant to at least three different classes of antimicrobials), and the level of drug resistance is increasing with time. There were three isolates (9.4%) exhibiting MDR from 1962 to 1968. MDR rates began to increase for isolates between 1970 to 1979 and 1980 to 1987 (64.6 to 78.7%). The MDR rates reached 96.6% for isolates between 1990 and 2010. Polymerase chain reaction screening for integrons showed that 75 isolates (22.3%) were positive for class 1 integrons while none were positive for class 2 integrons. All of the class 1 integron-positive isolates exhibited MDR and were more frequently resistant than the negative isolates. Two hundred and twenty isolates (65.3%) had the ability to form biofilms, and bacterial resistance levels to cefamandole, trimethoprim and trimethoprim/sulfamethoxazole were significantly higher for biofilm-positive groups than the biofilm-negative groups. Our data show that multidrug resistance is common among S. Pullorum isolated from eastern China, being more frequent after 1990 than before 1990, and the presence of class 1 integrons is associated with multidrug resistance.