Anthropogenic activities in the environment affect the ecosystem and can play an important role in selecting and spreading antibiotic‐resistant bacteria (ARB) and genes (ARGs). The dairy farm environment may serve as a hotspot and reservoir for exchanging and spreading ARGs, but studies are scarce. Here, we investigated and characterized the extended‐spectrum β‐lactamase producing Escherichia coli strains recovered from the dairy farm environment co‐harboring bla_OXA−1, catB3, and arr-3 genes. The isolates were identified and characterized by PCR, antimicrobial susceptibility testing, conjugation assay, whole genome sequencing (WGS), and multiple bioinformatics tools. Seven E. coli strains co‐harboring bla_OXA−1, catB3, and arr-3 genes were identified which belonged to distinct sequence types (STs) and carried diverse plasmid replicon types. The conjugation assay revealed a successful transfer of bla_OXA−1, catB3, and arr-3 genes into the recipient E. coli J53 with a co‐conjugation frequency ranging from (2.25 ± 0.3) × 10⁻⁴ to (3.85 ± 0.3) × 10⁻³. Bioinformatics analysis of WGS revealed the diversity of acquired ARGs, conferring resistance to aminoglycosides, beta‐lactams, quinolones, tetracyclines, macrolides, trimethoprim–sulfamethoxazole, phosphonic, phenicol, and rifamycin. The genetic environment analysis showed that aac(6^′)‐Ib-cr-bla_OXA−1‐catB3-arr-3-qacE1-sul1 was the common genetic backbone among the seven E. coli strains. Among the mobile genetic elements, insertion sequences were the predominant elements as compared to transposons. The phylogenetic analysis demonstrated a close relationship between the E. coli of this study and other strains of human–animal‐environment origin retrieved from the NCBI database. This study presented the whole genome‐based characterization of E. coli strains carrying the bla_OXA−1‐catB3-arr-3 genes. It provided evidence that the dairy environment may harbor a variety of ARGs and act as a potential reservoir for their spread in the ecosystem. The results recommend the routine surveillance of ARGs carrying bacteria in dairy environments and the need for additional studies to understand the dissemination mechanism within One Health perspective to prevent their further spread.

A total of 320 1-day-old broilers were randomly divided into five groups. The control group (CON) received a basal diet, while the FAP4, FAP2, and FAP1 groups were provided with the basal diet supplemented with 4%, 2%, and 1% fermented Astragalus powder, respectively. The unfermented Astragalus powder (UAP2) group was fed the basal diet supplemented with 2% UAP. Each group contained eight replicates of eight chicks each. The results revealed that the final BW and ADG in the FAP 1 and FAP2 were higher than those in the UAP2 and CON groups, while reducing F/G from day 14 to day 42. On day 42, the thymus index in the UAP and FAP groups as well as the bursa index in the FAP4 group showed significant increases compared to those in the CON group. Supplementation with 2% FAP elevated serum IgA levels in broilers on day 28 and day 42, and it also increased serum IgG levels on day 42. Furthermore, supplementation with 2% FAP elevated serum albumin (ALB) levels in broilers, while supplementation with 4% FAP increased serum (glucose) GLU levels in broilers on day 28. The serum biochemical parameters and pathological observation of the liver and kidney in the groups did not show any adverse effects on broilers’ health. In addition, the serum total antioxidant capacity (T-AOC) level significantly increased in the FAP4 and FAP2 groups on day 28, and the malondialdehyde (MDA) level in both serum and liver tissue decreased in the FAP2 group on day 28 and day 42. Compared to the CON group, 2% FAP and 2% UAP supplementation reduced the relative abundance of Bacteroides and supplementation with 2% FAP increased the relative abundance of Alistipes on day 42. In conclusion, the dietary supplementation of FAP can enhance the growth performance, immune function, and antioxidant capacity and regulate microflora in broilers, of which 2% FAP is more effective. It indicates FAP exhibits significant application potential as a promising feed additive for broilers.

Actinobacillus pleuropneumoniae (APP) is responsible for causing Porcine pleuropneumonia (PCP) in pigs. However, using vaccines and antibiotics to prevent and control this disease has become more difficult due to increased bacterial resistance and weak cross-immunity between different APP types. Naringin (NAR), a dihydroflavonoid found in citrus fruit peels, has been recognized as having significant therapeutic effects on inflammatory diseases of the respiratory system. In this study, we investigated the effects of NAR on the inflammatory response caused by APP through both in vivo and in vitro models. The results showed that NAR reduced the number of neutrophils (NEs) in the bronchoalveolar lavage fluid (BALF), and decreased lung injury and the expression of proteins related to the NLRP3 inflammasome after exposure to APP. In addition, NAR inhibited the nuclear translocation of nuclear factor kappa-B (NF-κB) P65 in porcine alveolar macrophage (PAMs), reduced protein expression of NLRP3 and Caspase-1, and reduced the secretion of pro-inflammatory cytokines induced by APP. Furthermore, NAR prevented the assembly of the NLRP3 inflammasome complex by reducing protein interaction between NLRP3, Caspase-1, and ASC. NAR also inhibited the potassium (K⁺) efflux induced by APP. Overall, these findings suggest that NAR can effectively reduce the lung inflammation caused by APP by inhibiting the over-activated NF-κB/NLRP3 signalling pathway, providing a basis for further exploration of NAR as a potential natural product for preventing and treating APP.

Objective: This study aimed to investigate the impact of Cordyceps militaris solid medium (CMM) on the growth performance, immunity parameters, intestinal health and gut microbiota of broilers.Methods: A total of 320 male broilers were randomly allocated into 4 groups, consisting of 8 replicates and 10 birds per replication. The broilers were fed diets comprising the Control group, 0.02% CMM group (Low CMM), 0.2% CMM group (Mid CMM), or 2% CMM group (High CMM). Samples were collected on 14d and 28d of the experiment. Serum was collected for the determination of biochemical indices and immunoglobulins, the intestinal morphology of the duodenum, jejunum and ileum was observed, and cecum contents were collected for 16S rRNA gene sequencing.Results: Over the course of the 28d trial, the broilers fed CMM had a higher average daily gain and lower feed conversion rate than the control broilers at Days 14 and 28. Notably, compared with those of the Control group, the Low CMM diet increased the thymus and bursa indices significantly (p<0.05). Enzyme-linked immunosorbent assay revealed that CMM increased the IgA, IgM, and IgG levels in the serum, and the IgA level in the Low and Mid CMM groups was significantly higher than that in the Control group (p<0.05). A Low CMM diet showed the strongest ability to increase villus height (VH) and villus height/crypt depth, and CMM affected the relative mRNA expression levels of inflammatory factors in jejunal tissue. The 16S rRNA results showed that the CMM group presented a greater relative abundance of Firmicutes and a higher Firmicutes/Bacteroidetes ratio than did the Control group at 14 d and 28 d, and the Deferribacteres abundance also increased (14 d). At the genus level, a Low CMM diet decreased Bacteroides abundance (p0.05).Conclusion: These results illustrate that 0.02% CMM in the diet can promote growth performance, increase immunity, improve intestinal morphology, and regulate the intestinal flora of broilers.