Recombinant protein technology has emerged as an excellent option for vaccine development. However, prior to our study, the immune induction ability of recombinant Mycoplasma suis alpha-enolase (rMseno) in animals remained unclear. The purpose of this study was to develop a rMseno protein subunit vaccine and to determine its ability to elicit an immunological response. To accomplish this, we cloned the gene into pET-15b, expressed it in BL21 cells, and purified it. Following the establishment of immunity, the immunogenicity and potential for protection of rMseno were evaluated in mice and piglets. The results demonstrate that anti-M. suis serum recognized the pure rMseno protein in both mice and piglets as evidenced by high levels of specific anti-rMseno antibodies, significantly increased levels of IFN-γ and IL-4 cytokines, and significantly increased T lymphocyte proliferation index. Piglets also had significantly increased levels of specific IgG₁, IgG_2a, CD4⁺, and CD8⁺ cells. The rMseno findings demonstrated a robust immunological response in mice and piglets, affording partial clinical protective efficacy in piglets.

Tick-borne diseases (TBDs) pose a significant public health challenge, as their incidence is increasing due to the effects of climate change and ecological shifts. The interplay between tick-borne pathogens and the host microbiome is an emerging area of research that may elucidate the mechanisms underlying disease susceptibility and severity. To investigate the diversity of microbial communities in ticks infected with vertebrate pathogens, we analyzed the microbiomes of 142 tick specimens. The presence of Rickettsia and Anaplasma pathogens in individual samples was detected through PCR. Our study aimed to elucidate the composition and variation of microbial communities associated with three tick species, which are known vectors for various pathogens affecting both wildlife and humans. We employed high-throughput sequencing techniques to characterize the microbial diversity and conducted statistical analyses to assess the correlation between the presence of specific pathogens and the overall microbial community structure. Pathogen screening revealed an overall positivity rate of 51.9% for Anaplasma and 44.6% for spotted fever group rickettsia (SFGR). Among the three tick species (Dermacentor silvarum, Haemaphysalis concinna, and Haemaphysalis japonica) analyzed, D. silvarum (the predominant species) exhibited the highest pathogen prevalence. The results indicate significant variation in microbial diversity between tick samples, with the presence of Anaplasma and SFGR associated with distinct changes in the microbial community composition. These findings underscore the complex interactions between ticks and their microbial inhabitants, enriching our understanding of tick-borne diseases.

Background: The unique eco-geographical patterns and climatic conditions of the China-Tumen River border region, combined with frequent cross-border tourism and trade activities, collectively establish this area as a recognized hotspot for tick-borne disease outbreaks. However, critical knowledge gaps persist regarding the eco-epidemiology of emerging tick-borne viruses and the distribution of their potential reservoir hosts within this trinational ecosystem spanning China, North Korea, and Russia. Methods: We collected a total of 2,004 ticks from the study area, along with blood samples obtained from 42 sheep and 45 cattle. Following viral metagenomic analysis of the ticks, dual verification of target pathogens in all samples was performed using qRT-PCR and RT-PCR assays. Phylogenetic trees were constructed and nucleotide sequences were analyzed to delineate relationships between the obtained virus strains and reference sequences. Results: Viral metagenomics identified three viruses in ticks: Dabieshan tick virus (DBTV), Songling virus (SGLV), and Yanggou tick virus (YGTV). PCR analysis detected DBTV exclusively in Hunchun ticks (minimum infection rates, MIR:4.73%) and YGTV in Antu specimens (MIR:0.97%). Conversely, SGLV was detected in ticks from all four regions, with MIR of 1.68% (Helong), 0.74% (Hunchun), 1.61% (Antu), and 4.79% (Longjing). Concurrently, SGLV was detected in 19 sheep blood samples from Longjing, yielding a positivity rate of 45.24%, while YGTV was identified in 13 cattle blood samples from Antu, with a positivity rate of 28.89%. Phylogenetically, the DBTV strain clustered with previously reported DBTV and Yongjia tick virus 1 isolates. Sheep-derived SGLV strains shared close evolutionary ties with tick-borne SGLV, whereas YGTV from cattle and ticks formed a distinct cluster with Russian strains but diverged into two branches from Chinese variants, suggesting evolutionary instability. Conclusion: These findings address critical knowledge gaps in the transmission dynamics and genetic diversity of emerging arboviruses while providing vital insights for developing cross-border surveillance strategies with significant public health implications.

The complete mitochondrial genome of Dermanyssus gallinae isolated from China is reported for the first time in this study. Its entire mitogenome is 16, 184 bp in length, contained 13 protein-coding genes, 2 ribosomal RNA genes, 21 transfer RNA genes, and 1 non-coding region. The phylogenetic analysis by maximum likelihood method show that D. gallinae isolated from China is in the same clade with the genus of Psoroptes. This is the first complete mitochondrial genome of D. gallinae.

The complete mitochondrial genome of Amblyomma testudinarium is reported for the first time in this study. Its entire mitogenome is 14,760 bp in length, contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 2 non-coding regions. The phylogenetic analysis by Bayesian inference method show that A. testudinarium and the others of genus Amblyomma are in the same clade, indicating that A. testudinarium belongs to the genus Amblyomma.

Bovine coronavirus (BCoV) is an important viral agent associated with neonatal calf diarrhea (NCD), winter dysentery, and bovine respiratory disease, contributing to economic losses in cattle production worldwide. To date, BCoV sequence data from Yanbian, Northeast China, are limited in public datasets. In this study, we report the first successful isolation of a BCoV strain (BCoV‐YBYJ) from a diarrheic calf in Yanbian using MDBK cells and characterize its replication in vitro and describe exploratory colon and lung findings following high‐dose oral exposure in a murine model. The isolate replicated efficiently in MDBK cells. In mice, viral RNA was detected in the colon and lung with mild‐to‐moderate histological changes under high‐dose exposure (nonnatural host). Phylogenetic analysis based on partial ORF1a, S, and M sequences showed that BCoV‐YBYJ clustered with contemporary Chinese isolates within the available reference set, supporting regional genetic relatedness based on partial loci. In parallel, three SYBR Green I‐based RT‐qPCR assays targeting BCoV, bovine rotavirus (BRV), and bovine parvovirus (BPV) were established and analytically validated. These assays demonstrated satisfactory analytical sensitivity, specificity, and reproducibility within the validated dynamic range, and BCoV RNA was detected in 70% (140/200) of targeted diarrheic calf specimens ( n = 200). This study provides a Yanbian BCoV isolate and analytically validated RT‐qPCR assays to support differential detection and surveillance of major viral agents associated with calf diarrhea. Because these were targeted submissions from diarrheic calves, this proportion is reported descriptively and should not be interpreted as population prevalence. The BRV and BPV assays underwent analytical validation only and require further clinical evaluation before routine diagnostic application.