Bovine respiratory syncytial virus (BRSV) is a common pathogen causing respiratory disease in cattle and a significant contributor to the bovine respiratory disease (BRD) complex. BRSV is widely distributed around the world, causing severe economic losses. This study we established a new molecular detection method of BRSV pathogen NanoPCR attributed to the combination of nano-particles in traditional PCR (Polymerase chain reaction) technology. In this study, the BRSV NanoPCR assay was developed, and its specificity and sensitivity were investigated. The results showed that no cross-reactivity was observed for the NanoPCR assay for related viruses, including the infectious bovine rhinotracheitis virus (IBRV), bovine viral diarrhea virus (BVDV), and bovine parainfluenza virus type 3 (BPIV3), and the assay was more sensitive than the conventional PCR assay, with a detection limit of 1.43 × 102 copies recombinant plasmids per reaction, compared with 1.43 × 103 copies for conventional PCR analysis. Moreover, thirty-nine clinical bovine samples collected from two provinces in North-Eastern China, 46.15% were determined BRSV positive by our NanoPCR assay, compared with 23.07% for conventional PCR. This is the first report to demonstrate the application of a NanoPCR assay for the detection of BRSV. The sensitive and specific NanoPCR assay developed in this study can be applied widely in clinical diagnosis and field surveillance of BRSV infection.

Background: Feline calicivirus (FCV), Feline panleukopenia virus (FPV), and Feline herpesvirus type I (FHV-1) are the three most common pathogens in cats, and also are the main pathogens leading to the death of kittens. Here, by a combination of gold nanoparticles and conventional PCR, we established a novel triple NanoPCR molecular detection method for clinical detection. Results: The triple NanoPCR molecular detection is able to detect 2.97 × 10¹copies/μL FCV recombinant copies plasmid per reaction, 2.64 × 10⁴copies/μL FPV recombinant copies plasmid per reaction, and 2.85copies/μL FHV-1 recombinant copies plasmid per reaction at the same time. The sensitivity of each plasmid is 100 times, 10 times, and 100 times higher than conventional PCR, respectively. The clinical results showed that among the 38 samples, the positive rates of FCV, FPV, and FHV-1 in a NanoPCR test were 63.16, 31.58, and 60.53%, while in a conventional PCR were 39.47, 18.42, and 34.21%. Conclusions: In this report, it is the first time that NanoPCR assays are applied in the detection of FCV, FPV, and FHV-1 as well. This sensitive and specific NanoPCR assay can be widely used in clinical diagnosis and field monitoring of FCV, FPV, and FHV-1 infections.

The gut microbiota of the Tibetan antelope (Pantholops hodgsonii) plays a vital role in host nutrition, particularly by contributing to the biosynthesis of

Antimicrobial resistance (AMR) in Escherichia coli from livestock poses a growing public health threat, yet genomic data on cattle-derived strains in China remain limited. This study investigated AMR, virulence, and plasmid profiles of E. coli from diarrheic cattle in four provinces: Anhui (AH), Ningxia (NX), Shandong, and Shanxi (SX). Ninety-one isolates were characterized using antimicrobial susceptibility testing and whole-genome sequencing. Resistance to ampicillin (49.5%), cefotaxime (37.4%), and tetracycline (36.3%) was common, with NX showing the highest resistance rate. Twenty-one multidrug-resistant strains were identified, mainly from NX and SX. Genomic analysis revealed 53 distinct antibiotic resistance genes (ARGs), predominantly mdf ( A ), aph (6)- Id , and tet (A), with the highest burdens in NX and SX. Among 196 virulence genes, adherence ( fim and csg ) and secretion systems ( espX , espR ) predominated, with AH showing the greatest diversity. Plasmid profiling detected 37 replicon types, with incompatibility FIB (IncFIB) being the most abundant. A strong correlation between plasmids and ARGs was found ( r = 0.626, P  < 0.001), with key ARGs [ bla _CTX-M-55 , tet (A)] located on IncI1 and IncX1 plasmids, while most virulence genes were chromosomal. Molecular typing identified 45 sequence types (STs) and 59 serotypes, with ST29 (O26:H11) unique to AH and ST1011 (O86:H51) to NX. Phylogenetic analysis revealed clustering by phylogroup, with shared STs and serotypes across regions, indicating clonal and geographic dissemination. These findings underscore the genomic diversity and dissemination risk of AMR E. coli in Chinese cattle, highlighting the need for region-specific surveillance. IMPORTANCE: The growing threat of antimicrobial resistance (AMR) in Escherichia coli from livestock raises serious concerns for both animal and public health, especially under the One Health framework. Genomic information on cattle-derived E. coli in multi-regions of China has been limited, hindering our understanding of regional AMR patterns. This study addresses that gap by analyzing isolates from diarrheic cattle across four provinces, uncovering clear geographic variation in resistance profiles, virulence traits, and plasmid content. The identification of clinically relevant resistance genes such as bla _CTX-M-55 and tet (A) on plasmids indicates a high potential for horizontal gene transfer. The strong association between plasmid types and resistance gene burden highlights key targets for surveillance. These findings offer valuable insights into the molecular epidemiology of bovine E. coli and support more effective, region-specific strategies to monitor and control the spread of AMR in livestock.

Objective: The proportion of n-6/n-3 polyunsaturated fatty acid (PUFA) plays an important role in regulating lipid metabolism. This study aimed to investigate the effects of dietary n-6/n-3 PUFA ratios on body fat deposition, tissues fatty acid composition, and gene expression of liver lipid metabolism of silver foxes during the winter fur growth period.Methods: Forty-eight age-matched male silver foxes with similar body weights were randomly divided into four dietary groups for 47 days, which were fed n-6/n-3 PUFA ratio with 3, 18, 41, and 136 experimental diets, respectively.Results: Dietary n-6/n-3 PUFA ratio did not significantly influence fat deposition parameters except for hepatic fat content. The variation trend of the fatty acid composition of liver, intramuscular fat, and subcutaneous fat in silver fox was directly related to dietary fatty acid content (p < 0.05). With the dietary n-6/n-3 PUFA ratio increasing, the expression of liver fatty acid synthase (FAS) mRNA and peroxisome proliferator-activated receptor (PPAR) mRNA exhibited the trend of first decreasing and then increasing (p < 0.05), whereas L-fatty acid binding protein (L-FABP) mRNA expression showed a gradual increasing trend (p < 0.05).Conclusion: In summary, silver foxes fed an n-6/n-3 PUFA ratio 18:1 diet (supplementing with 9.38% corn oil and 4.62% soybean oil) was more conducive to lipid decomposition, PUFA transport, and utilization of tissues, thereby meeting it for supplying energy and withstanding the cold.