Global warming increases the risk of heat-related renal impairment, while higher ambient temperatures may increase overall fluid and beverage consumption to meet hydration demands. As erythritol is widely used as a dietary sweetener in food and beverage products and is primarily excreted via the kidneys, concerns have been raised regarding its renal effects, particularly under conditions of heat stress. Here, we used integrated metabolomic and transcriptomic analyses to explore erythritol's role in heat-induced renal injury in mice. Erythritol supplementation modulated oxidative stress, inflammation, and lipid metabolism, with metabolomics showing recovery of redox-related metabolites and transcriptomics revealing downregulation of pro-inflammatory genes (e.g., Cxcl9, Serpina3g) and stress chaperones, alongside upregulation of antioxidative genes (e.g., Gbp6, Tgtp1). Multi-omics highlighted PPAR and AMPK pathways as key targets. Animal experiments confirmed improved renal histology, reduced creatinine, and decreased oxidative and inflammatory markers. These findings indicate that erythritol protects against heat-induced renal damage, supporting its potential as a functional food ingredient for thermally stressful conditions.

Microplastics (MPs) can adsorb and transport heavy metals, but their influence on cadmium (Cd)-induced hepatotoxicity in mammals remains unclear. Forty-eight male Kunming mice were assigned to control, Cd, MP, and Cd + MP groups and exposed by oral gavage for 42 days. Growth performance, liver injury, oxidative stress, and inflammation were assessed, and transcriptomic and metabolomic analyses were integrated with qPCR, mitochondrial DNA (mtDNA) copy number, and ATP measurements. Compared with Cd alone, combined exposure resulted in greater reductions in body weight gain, the liver index, and antioxidant enzyme activities, together with more severe hepatic lesions and higher levels of liver injury markers and inflammatory cytokines. Co-exposure also induced broader transcriptional and metabolic disturbances than Cd alone. Integrated omics analyses converged on the dysregulation of AMPK–FOXO signaling and related energy metabolic processes. qPCR confirmed more pronounced alterations in pathway-related genes after co-exposure, while reductions in mtDNA copy number and ATP content indicated aggravated mitochondrial dysfunction and impaired energy metabolism. Collectively, these results demonstrate that MPs exacerbate Cd-induced liver injury and suggest that disruption of AMPK–FOXO-associated energy metabolism is a key molecular feature underlying the enhanced hepatotoxicity observed under combined exposure.

Canine parvovirus (CPV) is the primary cause of viral enteritis in dogs, while canine bocavirus (CBoV) and canine bufavirus (CBuV) have emerged as significant components of the canine enteric virome. Previous studies on CPV in Sichuan had limited geographic coverage and sample size, and lacked data on CBoV and CBuV. This study used PCR to investigate the genetic diversity of CPV, CBoV and CBuV and to examine their co-infection status in diarrheic dogs across five regions of Sichuan between 2020 and 2022. The results revealed that CPV-2 was the most prevalent virus (33.3%, 48/144), while CBoV (5.56%, 8/144) and CBuV (4.17%, 6/144) were detected for the first time in Sichuan province. Genetic analysis revealed CPV-2c to be the predominant genotype (95.8% (46/48)), replacing the previously circulating strains CPV-2a and CPV-new 2a. The study also identified several typical and novel mutations in the VP2 protein in the CPV-2c strains, including Ala5Gly, Trp214Cys and Thr440Ala. Additionally, four co-infection cases (2.78%) were observed, including a triple CPV/CBoV/CBuV infection in Xichang (XC05). Phylogenetic analysis revealed genetic diversity, with CBoV strains clustering into CBoV-1 and CBoV-2 subspecies, while CBuV strains formed two distinct clusters. Our findings emphasize the need for ongoing monitoring of the dynamic epidemiological situation of CPV, CBoV and CBuV in Sichuan Province.

Global warming has increasingly positioned heat stress (HS) as a major threat to public health, as it can inflict damage on multiple organs including the kidneys, liver, and heart. However, effective targeted therapeutic strategies remain limited. This investigation employed an integrated approach combining Network pharmacology, in silico binding simulations, and cell-based assays to elucidate the cytoprotective properties and molecular basis of oxymatrine action under heat-stressed conditions. Network analysis identified 36 overlapping targets common to oxymatrine and the pathological processes of HS-related acute kidney injury (AKI), acute liver injury (ALI), and acute myocardial injury (AMI). These targets were strongly enriched in the PI3K-AKT signaling cascade. Molecular docking showed that oxymatrine binds tightly to key pathway proteins such as PIK3CA and GSK3B, with Vina scores below -8 kcal/mol. In 293T cells, the half-maximal cytotoxic concentration (CC50) of oxymatrine exceeded 2000 μM. Under heat stress, oxymatrine (31.25-1000 μM) dose-dependently increased cell viability by about 30% and significantly lowered HSP90 and HSP70 expression. Similar protective effects were observed in H9C2 cardiomyocytes under heat stress. RT-qPCR further confirmed that oxymatrine reduced the transcript levels of PI3K-AKT pathway-related genes, including CASP3, EGFR, RXRα, and MMP9 in 293T cells. We also found 18 overlapping targets between oxymatrine and ferroptosis, most of which matched the core targets above. Molecular docking analysis predicted binding of oxymatrine to the ferroptosis regulator GPX4. Together, these results suggested that oxymatrine potentially alleviates HS injury by modulating the PI3K-AKT signaling pathway andregulating potential ferroptotic targets such as GPX4.

BackgroundAcute Kidney Injury (AKI) is a critical clinical syndrome with high morbidity and mortality, yet effective therapeutic agents are lacking. The Rheum-Salvia miltiorrhiza (R-S) combination, a traditional Chinese herbal pair, has been used to treat acute kidney injury, but its mechanisms remain unclear.ObjectiveThis study aimed to evaluate the nephroprotective effects of the R-S combination on cisplatin-induced AKI and to elucidate its underlying mechanisms through integrated multi-omics analyses.MethodsMale C57BL/6 mice were randomly divided into five groups: Control group (Control), AKI model group (Model), Rheum-S. miltiorrhiza low-dose group (R-S-low), Rheum-S. miltiorrhiza high-dose group (R-S-high), and curcumin group (Cur). AKI was induced by a single intraperitoneal injection of cisplatin (15 mg/kg). After the experiment, renal function was assessed by measuring serum creatinine (Cr) and blood urea nitrogen (BUN). Inflammatory cytokines and oxidative stress markers were detected using ELISA. Histopathological changes of the kidney tissue were evaluated by H&E staining. Gut microbiota composition, the cecal content metabolome and the renal transcriptome were further analyze. The MAPK signaling pathway in renal tissue was examined via RT-qPCR and Western blot.ResultsR-S treatment significantly improved renal function, lowering Cr and BUN, and attenuated renal histopathological injury. It also reduced oxidative stress and inflammation, elevating SOD and GSH, while decreasing IL-1β and TNF-α. Gut microbiota analysis showed that R-S restored microbial diversity, suppressed Escherichia-Shigella, and promoted Lachnospiraceae_NK4A136_group. Metabolomics identified 1237 differential metabolites, with enrichment in linoleic acid metabolism. Transcriptomics revealed 3530 differentially expressed genes, primarily associated with the MAPK signaling pathway. Molecular validation confirmed that R-S downregulated the mRNA expression of IL-1β, IL-6, TNF-α, MAPK 14, MAPK 8, NFKB 1, FOS, and JUN, and suppressed the phosphorylation of p38 MAPK, JNK, and NF-κB p65.ConclusionThe R-S combination alleviates cisplatin-induced AKI by modulating the gut microbiota, regulating metabolic profiles, and suppressing the MAPK signaling axis. This study provides a holistic, multi-omics perspective on the mechanisms of R-S, supporting its potential as a therapeutic agent for AKI.

Tooth wear is a major health and welfare issue for captive giant pandas (Ailuropoda melanoleuca), but quantitative data on wear progression across different tooth types and chewing behaviors are lacking. In this study, a two-dimensional computer simulation (Processing, Java-based) was developed to model wear of giant panda canine, second premolar, and second molar teeth under two bamboo-chewing orientations (horizontal vs. vertical). Species-specific enamel hardness (344 HV), bite forces (canine: 1030 N; premolar: 1142 N; molar: 2005 N), and a stochastic chewing cycle were incorporated into the simulation. The results showed that canine wear was faster during horizontal chewing (45.68 pixel layers/100 cycles) than during vertical chewing (36.76 pixel layers/100 cycles), while premolar and molar wear were faster during vertical chewing (34.24 and 51.52 pixel layers/100 cycles, respectively) compared to horizontal chewing (10.28 and 39.40 pixel layers/100 cycles). Molars exhibited the highest overall wear rate. The predicted functional lifespan was estimated to be 47~55 years for canines; 19~34 years for premolars; and 23~29 years for molars. This study provides the first quantitative, cycle-by-cycle wear progression model for giant panda teeth.

Three pathogenic species of the genus Yersinia, including Plague-associated Yersinia pestis, Yersinia pseudotuberculosis, and Yersinia enterocolitica, are commonly associated with human infection. Current qPCR detection methods are mainly limited to the identification of one or two Yersinia species in a single reaction tube, while multiplex assays for multiple genera have been more commonly reported. Therefore, the present study aimed to establish a multiplex TaqMan qPCR assay for the simultaneous detection of these three pathogenic Yersinia species. Primer and probe sets were designed based on the inv gene for Y. pseudotuberculosis, the caf1 gene for Y. pestis, and the foxA gene for Y. enterocolitica. Under the optimized reaction conditions, the standard curve slopes for the caf1, inv, and foxA genes were −3.046, −2.968, and −2.948, respectively. The correlation coefficients (R2) ranged from 0.993 to 0.996, while the amplification efficiencies ranged from 109% to 115%. The limits of detection (LOD) were determined to be 5 × 102 copies/μL for inv (FAM), 1 × 101 copies/μL for caf1 (ROX), and 1 × 101 copies/μL for foxA (CY5). The sensitivity of the multiplex qPCR assay was 10- to 100-fold higher than that of conventional PCR, depending on the target. Specificity experiments demonstrated that no cross-reactivity was observed with non-target bacteria, including Francisella tularensis, Brucella spp., Vibrio cholerae, Salmonella Typhi, and Shigella spp. The intra-assay coefficients of variation (CVs) ranged from 0.13% to 0.79%, whereas the inter-assay CVs ranged from 0.62% to 2.61%. Among 173 spleen samples collected from wild rodents, no positive signal for Y. pestis or Y. pseudotuberculosis was detected. In contrast, Y. enterocolitica was detected in three samples (1.73%, 3/173). In conclusion, the multiplex qPCR assay developed in this study provides a sensitive and specific tool for the simultaneous detection of three pathogenic Yersinia species and has the potential to improve detection efficiency in clinical and epidemiological investigations.

Post–core restoration serves as an effective treatment for fractured canine teeth. However, the influence of post length on the stability of the teeth for small animals remains controversial. This study employs finite element analysis and a force machine in vitro to evaluate the biomechanical effects of varying fiber post lengths in maxillary canine teeth, aiming to establish theoretical guidelines for optimizing post–core restoration in canine dentistry. Three-dimensional models of the canine teeth of large, medium, and small dogs (German Shepherds, Beagles, and Teddy dogs) were constructed using finite element analysis (FEA). Fiber posts with post-to-root length ratios of 1/3, 1/2, and 2/3 were established. Stress distribution (σ1/σ2) and total deformation under 100–1100 N loading were analyzed virtually in ANSYS (version 17.0.0.19190), as well as in a force machine in vitro. FEA and in vitro fracture tests showed good correlation (p > 0.05). Fracture loads for large, medium, and small breeds were 1115.851 ± 6.984 N (distal) and 1177.39 ± 5.82 N (lingual), 901.627 ± 7.49 N (distal) and 976.504 ± 6.399 N (lingual), and 812.733 ± 5.476 N (distal) and 897.642 ± 6.42 N (lingual), respectively. The fiber post with a root–post ratio of 2/3 exhibited the highest fracture resistance, potentially making it be the best choice for post–core restoration.

Acute respiratory distress syndrome (ARDS) is a critical pulmonary disorder with manifestations of pulmonary edema, inflammation, and impaired oxygenation. Establishing reliable animal ARDS models has been critical for investigating its mechanisms and for testing pharmacological interventions. The present study sought to induce a moderate ARDS model in New Zealand White rabbits with a model involving a mix of lipopolysaccharide (LPS), oleic acid (OA), and ventilation-induced lung injury (VILI). Four experimental groups were established: negative control (NC, n = 4), OA (OM, n = 6), LPS + OA (LOM, n = 6), and LPS + OA + VILI (LOV, n = 6). Throughout the modeling process, vital signs (MAP and HR), respiratory parameters (Cdyn), and hematological indices (WBC and P/F) were continuously monitored, and lung ultrasound was performed. After the experiment, bronchoalveolar lavage fluid (BALF) was collected to measure total protein content, and lung tissue samples were collected to determine the wet-to-dry (W/D) ratio. HE-stained lung tissue sections were prepared and scored according to the ATS guidelines for lung injury scoring. The LOV group showed the most severe lung injury, significantly decreasing MAP and Cdyn. Pathological and ultrasound scores were considerably higher in the LOV group compared to the OM and LOM groups (p < 0.05). The lung W/D ratio was significantly higher in the LOM (6.68 ± 0.56) and LOV (7.40 ± 0.56) groups compared to the NC group (5.20 ± 0.16) (p < 0.05). At T6, the PaO2/FiO2 ratio in the LOV group was ≤200 mmHg, significantly lower than that in the NC group (p < 0.05). Some rabbits in the OM and LOM groups also had PaO2/FiO2 ratios ≤200 mmHg, but the difference compared to the NC group was not statistically significant. In conclusion, this study established a novel moderate ARDS model in New Zealand White rabbits using LPS, OA, and VILI. The model demonstrates severe lung damage, pulmonary edema, and sustained hypoxemia, providing a basis for future research.

Proteus mirabilis is a zoonotic pathogen that poses a growing threat to both animal and human health due to rising antimicrobial resistance (AMR). It is widely found in animals, including China’s nationally protected captive giant and red pandas. This study isolated Proteus mirabilis from panda feces to assess AMR and virulence traits, and used whole-genome sequencing (WGS) to evaluate the spread of resistance genes (ARGs) and virulence genes (VAGs). In this study, 37 isolates were obtained, 20 from red pandas and 17 from giant pandas. Multidrug-resistant (MDR) strains were present in both hosts. Giant panda isolates showed the highest resistance to ampicillin and cefazolin (58.8%), while red panda isolates were most resistant to trimethoprim/sulfamethoxazole (65%) and imipenem (55%). Giant panda-derived strains also exhibited stronger biofilm formation and swarming motility. WGS identified 31 ARGs and 73 VAGs, many linked to mobile genetic elements (MGEs) such as plasmids, integrons, and ICEs. In addition, we found frequent co-localization of drug resistance genes/VAGs with MGEs, indicating a high possibility of horizontal gene transfer (HGT). This study provides crucial insights into AMR and virulence risks in P. mirabilis from captive pandas, supporting targeted surveillance and control strategies.

BACKGROUND:Biofilm-associated lung infections, particularly those caused by Staphylococcus aureus (S. aureus), pose significant clinical challenges to conventional therapies. S. aureus Biofilm infections are refractory to treatment due to the presence of persister bacterial cells and the barrier effect of unique extracellular polymeric substances (EPS). RESULTS:This study describes the development of multifunctional micelles, HK-SL Ms, utilizing sophorolipid (SL) to encapsulate Honokiol (HK). HK-SL Ms potently disrupted the EPS barrier, killed some internal colonizing bacteria, and inhibited further bacterial adhesion. Consequently, the dynamic cycling of biofilms was hindered, achieving a promising removal of S. aureus biofilms. In vitro studies demonstrated that HK-SL Ms exhibited significant antimicrobial reduction of a 6.42 log10CFU/mL. HK-SL Ms eradicated 71.73% of biofilms by targeting extracellular polysaccharides, extracellular proteins, and viable cells within the biofilm. Additionally, 1.66 log10CFU/mL units of S. aureus within biofilms were killed. Moreover, HK-SL Ms inhibited 91.10% of early S. aureus biofilm formation by obstructing initial bacterial adhesion and the formation of extracellular polysaccharides and polysaccharide intercellular adhesins (PIA). Thus, the reestablishment and reinfection of S. aureus biofilms could be resolved promisingly. Biofilm infections are as predominant in acute pneumonia as in chronic cases, inducing similar lung inflammation. In a murine model of pneumonia infected by S. aureus, HK-SL Ms significantly reduced the bacterial load in the lungs, decreased inflammatory factor levels, and repaired lung tissue damage. CONCLUSIONS:HK-SL Ms offers a novel strategy for the clinical treatment of biofilm-associated infections by dispersing and removing S. aureus biofilms and preventing new infections.

Heat stress-induced liver injury is a common and potentially life-threatening complication of heat exposure in both humans and animals. With the ongoing rise in global temperatures, effective preventive strategies are urgently needed. Lactic acid bacteria have been extensively studied and shown to effectively alleviate various types of liver injury; however, their specific role in heat stress-induced liver damage remains unknown. In our previous work, we isolated Lactobacillus plantarum L19 (LP-19), a strain with strong heat resistance and antioxidant capacity, from Holstein cow milk, suggesting its potential to benefit animals and humans under heat stress. This study aimed to investigate the effects of LP-19 against heat stress-induced liver injury using a mouse model. The results showed that oral administration of LP-19 reduced serum alanine aminotransferase and aspartate aminotransferase levels and inhibited liver oxidative stress in mice with heat-stressed liver injury. Immunohistochemistry and quantitative real-time PCR results showed that LP-19 also reduced levels of heat shock proteins and inflammatory factors. Moreover, LP-19 improved intestinal morphology and modulated gut microbiota by increasing beneficial genera such as Lactobacillus and Dorea while decreasing harmful taxa, including Haemophilus and Desulfovibrionaceae. These changes in the microbiota were closely correlated with therapeutic indices. Functional prediction with PICRUSt2 indicated that the LP-19-regulated microbiota may exert its effects primarily through modulating membrane transport, carbohydrate metabolism, and amino acid metabolism. These findings suggest that LP-19 may help prevent heat stress-induced liver injury by modulating the gut microbiota. Consequently, the study highlights the potential of LP-19 as a novel food additive for preventing heat stress-induced liver injury, offering new prospects for the utilization and the development of cow milk-derived lactic acid bacteria.

Introduction: Post-weaning Diarrhea (PWD) is a kind of physiological stress diarrhea in Rex rabbits after weaning, which can lead to death in severe cases. Traditional Chinese medicine (TCM) has been widely used in animal due to its advantages of natural origin, diverse functions, safety, reliability, economy and environmental protection. Modified Yupingfeng Granule (MYPFG) is an improved Yupingfeng prescription based on the famous traditional Chinese prescription Yupingfeng (YPF), which is combined with other TCM and has obvious synergistic and additive activity in order to obtain an excellent natural medicine for PWD. Methods: In this study, 120 weaned Rex rabbits were randomly allocated to 4 treatment groups, including control (CON), low dose (LD), medium dose (MD), high dose (HD). Rabbits were fed a control diet or a different MYPFG proportions of diet for 30 days. The study combined 16S rRNA analysis of intestinal microbiota and cecal contents metabolomics to explore the MYPFG effect on weaned Rex rabbits. Results: MYPFG increased average daily gain, villus length to crypt depth ratio and decreased the feed to meat ratio, diarrhea frequency, mortality rate, depth of crypt (p < 0.05). The intestinal microbiota test found that MYPFG could change the abundances of Patescibacteria, Sphingobium, Ruminococcus, and Oxalobacter. Metabolomics analysis found that effect may be related to its regulation of Glycine, serine and threonine metabolism, Arginine and proline metabolism. Nicotinate and nicotinamide metabolism. Discussion: MYPFG could regulate intestinal microbiota and change the metabolic pathway of some amino acids to alleviate the PWD in Rex rabbits.

Probiotics, particularly strains of lactic acid bacteria (LAB), are recognized for their beneficial effects on gut health. Lactobacillus acidophilus L177, a promising probiotic strain isolated from canine feces, was evaluated for safety and probiotic properties through whole genome sequencing and a 28-day subacute oral toxicity study in C57BL/6 mice. The toxicity study involved daily administration of L177 at doses of 108, 109, and 1010 CFU/mL, with continuous monitoring of general health, behavioral changes, and physiological parameters. Body weight, food and water intake, hematological and biochemical indices, organ weights, and histopathology were assessed. No significant adverse effects were observed, and proinflammatory cytokines (TNF-α, IL-6, IL-1β) remained undetectable in serum, indicating an absence of inflammatory response. Statistical analysis confirmed no significant differences in key health markers between treated and control groups (p > 0.05). Whole genome sequencing revealed a single chromosome of approximately 1,972,211 base pairs (GC content: 35.02

Background:Canine Circovirus (CanineCV) is a non-enveloped, single-stranded circular DNA virus in the Circoviridae family, known to cause respiratory and diarrheal diseases in dogs. It can also lead to immune suppression, which may worsen symptoms during co-infection. The virus's Replication (Rep) and Capsid (Cap) proteins play crucial roles in its life cycle. This study explores a novel truncated Rep' mutant of CanineCV and examines its impact on feline health when co-infected with Feline Panleukopenia Virus (FPV). Method:We constructed and validated clones and plasmids for CanineCV/ SC49 (which carries the normal Rep gene) and CanineCV/SC50 (which carries the truncated Rep'gene). Virus particles were visualized using transmission electron microscopy (TEM), while quantitative polymerase chain reaction (qPCR) assessed viral load. Additionally, we examined the effects of Rep and Rep' proteins on cellular viability, their roles in FPV replication, and the host interferon type I (IFN-I) response. Results:The Rep' protein significantly enhances the cytotoxicity of CanineCV against the F81 cell line, outperforming the Rep protein in this regard. However, when assessing the proliferation-promoting effects on FPV, both proteins demonstrated positive effects, but Rep exhibited a significantly greater impact than Rep' Additionally, qPCR analysis revealed that Rep has a stronger inhibitory effect on the expression of IFN-α, IFN-β, MxA, and ISG15 genes compared to Rep'. Conclusion:This study underscores the dual roles of Canine Circovirus in modulating host cell viability. On one hand, it enhances the replication of co-infecting viruses; on the other hand, it suppresses the host's antiviral responses. These findings provide valuable insights into the pathogenic mechanisms of Canine Circovirus.

The rapid spread of extended-spectrum β-lactamases (ESBLs)-producing Escherichia coli (ESBL-EC) around the world has become a significant challenge for humans and animals. In this study, we aimed to examine the characteristics and horizontal gene transfer (HGT) capacity of ESBL-EC derived from captive primates. We screened for ESBL-EC among a total of 444 multidrug-resistant (MDR) E. coli strains isolated from 13 zoos in China using double-disk test. ESBL genes, mobile genetic elements (MGEs), and virulence-associated genes (VAGs) in ESBL-EC were detected through polymerase chain reaction (PCR). Furthermore, conjugation experiments were conducted to examine the HGT capacity of ESBL-EC, and the population structure (phylogenetic groups and MLST) was determined. Our results showed that a total of 69 (15.54%, 69/444) ESBL-EC strains were identified, and 5 variants of blaCTX and 3 variants of blaTEM were detected. The highest detection rate was blaCTX-M-55 (49.28%, 34/69), followed by blaCTX-M-15 (39.13%, 27/69). Ten MGEs were detected and the most prevalent was IS26 (78.26%, 54/69), followed by ISEcp1 (60.87%, 42/69). Eighteen combinations of MGEs were detected, in which ISEcp1 + IS26 was predominant (18.84%, n = 13). A total of 15 VAGs were detected and the most prevalent was fimC (84.06%, 58/69), followed by sitA (78.26%, 54/69). Furthermore, HGT ability analysis results showed that 40.58% (28/69) of ESBL-EC strains exhibited the ability to engage in conjugative transfer. Plasmid typing revealed that IncFIB (78.57%, 22/28) had the highest detection rates. Furthermore, antibiotic resistance genes (ARGs) of blaTEM-135, tetA and qnrS; MGEs of IS26, trbC and ISCR3/14 showed high rates of conjugative transfer. The population structure analysis showed that the phylogroup B1 and ST2161 were the most prevalent. ESBL-EC poses a potential threat to captive primates and may spread to other animals, humans, and the environment. It is imperative to implement measures to prevent the transmission of ESBL-EC among captive primates.

The emergence and global dissemination of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-E. coli) represent a major public health concern. However, the characterization and capacity for horizontal gene transfer (HGT) of ESBL-E. coli in captive black bears remain substantially understudied. In the present study, 19 ESBL-E. coli strains were successfully identified (13.38%, 19/142). A total of 11 sequence types (STs) were identified from 19 ESBL-E. coli strains using MLST. This included eight known types (ST10, ST2690, ST208, ST695, ST4160, ST540, ST3865 and ST2792) and three new STs. Antimicrobial susceptibility testing demonstrated that all 19 ESBL-E. coli exhibited high resistance to KZ (100.00%), CRO (78.95%), and CTX (73.68%). Polymerase chain reaction (PCR) screening for 14 β-lactam antibiotic resistance genes (ARGs) and their variants revealed that blaCTX-M was the most prevalent, followed by blaSHV, blaTEM, and blaDHA. Furthermore, eight β-lactamase variants were detected, including five blaCTX-M variants (blaCTX-M-15, blaCTX-M-3, blaCTX-M-14, blaCTX-M-55, and blaCTX-M-27) and one variant each of blaSHV-1, blaTEM-1, and blaDHA-14. Conjugation assays revealed that eight ESBL-E. coli strains were capable of conjugative transfer. Five plasmid types (IncFII, IncW, IncFrepB, IncY, and IncHI1) and three mobile genetic elements (MGEs) (IS26, ISEcp1, and trbC) were identified as co-transferred with blaCTX-M. ESBL-E. coli poses a potential threat to captive black bears and may lead to further transmission. Consequently, the implementation of continuous surveillance and targeted interventions is imperative to prevent the transmission of ESBL-E. coli.

The anaerobic unicellular protist Blastocystis is widely recognised for its presence in the gastrointestinal systems of humans and various animals globally. However, there is a paucity of reports on the prevalence and subtype (ST) distribution of Blastocystis in the squirrel population. This study was conducted to determine the prevalence and genetic diversity of Blastocystis, as well as its zoonotic potential, among Sciurus vulgaris and Sciurus vulgaris exalbidus in Chengdu, China. A total of 41 faecal samples (31 from Sciurus vulgaris, 10 from Sciurus vulgaris exalbidus) were analysed for the presence of Blastocystis sp. using the polymerase chain reaction (PCR) amplification of the small subunit ribosomal RNA (SSU rRNA) gene. Our findings revealed a positive rate of 4.88% (2/41 samples) for Blastocystis sp., with both identified as ST4 through nucleotide sequence homology and phylogenetic analysis. Given the zoonotic nature of this subtype, farmed squirrels may serve as potential reservoirs for Blastocystis transmission to humans and domestic animals. These findings are essential for developing effective control strategies against Blastocystis in the study region and enhancing our comprehension of the genetic spectrum of Blastocystis within Sciurus vulgaris and Sciurus vulgaris exalbidus.

This study aims to evaluate the feasibility and accuracy of 3D printing-guided endodontics in the maxillary teeth of dogs. CT data from a Beagle dog were processed to create a 3D model of the maxilla, and virtual root canal pathways were established using SOLIDWORKS software (version 29.0.0.5028). Guided endodontic templates were 3D printed and tested in vitro on 20 maxillary teeth (excluding the third molars), with 36 root canals treated using both guided and conventional methods. Results indicated that 3D printing-guided endodontics provided accurate root canal pathways, with minimal deviations in length (average 3.08 ± 1.75%) and angular alignment (average 2.06° ± 0.5°) compared to conventional methods. This research represents a significant step forward in the application of 3D printing technology in veterinary endodontics, offering a promising alternative to traditional methods for treating complex dental conditions in dogs.