This study aims to investigate the effect of bovine leukemia virus encoded microRNAs(BLV-miRNAs)on lactoperoxidase(LPO)in bovine mammary epithelial cells(BMECs).Firstly,the LPO content in the milk of BLV-positive cows,categorized by different viral loads,was quanti-fied by enzyme-linked immunosorbent assay(ELISA).Subsequently,BMECs were cultured in vitro and infected with(1 MOI)full-length BLV and BLV lacking miRNAs(BLV-ΔmiRNAs).Va-rious analytical techniques,including fluorescent quantitative PCR and ELISA,were used to assess LPO expression levels in different BMEC cohorts.Ten BLV-miRNAs were computationally predic-ted to target LPO using software tools such as StarMir.Based on these predictions,transfections of BLV-miRNAs were carried out and preliminary verification of their effects on target genes were performed.The results showed that compared to that of BLV-negative counterparts,the LPO levels in the milk of BLV-positive cows,stratified by high and low viral load,decreased by 8.73％and 9.68％,respectively.Invitro experiments further corroborated these trends,revealing a significant increase(P＜0.05)in LPO expression within BMECs following the deletion of BLV-miRNAs compared to the group infected with full-length BLV-infected group.Computational target site pre-dictions implicated BLV-miR-B1-5p,B3-3p,and B4-5p in the collective regulation of the LPO gene.Transfection of BLV-miR-B1-5p into BMECs resulted in a significant downregulation of LPO gene expression(P＜0.05),with the effect intensifying proportionally with the transfection dose.Simi-larly,the transfection of BLV-miR-B4-3p into BMECs significantly reduced LPO gene expression(P＜0.05)without showing a dose-dependent behavior.In conclusion,this research indicates that BLV-miRNAs can suppress LPO expression in BMECs.

Objective To compare the efficiency of multiple etiological techniques for detection of Schistosoma japonicum infections in wild mice, so as to provide technical supports to assessment of schistosomiasis transmission risk. Methods Wild mice were captured with baited traps at night in Oncomelania hupensis snail-infested settings in schistosomiasis-endemic foci of Anhui Province from October to November, 2022. S. japonicum infections were detected in wild mice using microscopy of mouse liver tissues, microscopy of mouse mesenteric tissues, microscopy of mouse liver tissue homogenates, miracidial hatching test of mouse liver tissue homogenates, Kato-Katz technique and miracidial hatching test of mouse stool samples alone and in combinations. Identification of S. japonicum eggs or miracidia by any of these six assays was defined as an infection. The sensitivity of six assays alone or in combinations was compared for detection of S. japonicum infections in wild mice. Results A total of 1 703 wild mice were captured, with 366 wild mice detected positive for S. japonicum (21.49%). There were significant differences in the prevalence of S. japonicum infections in wild mice by six assays (Q = 529.33, P < 0.001) and in the sensitivity of six assays for detection of S. japonicum infections in wild mice (χ² = 527.78, P < 0.001). In addition, the combination of microscopy of mouse liver tissues and mesenteric tissues, combination of microscopy of mouse liver tissues and liver tissue homogenates and combination of microscopy of mouse liver tissues, microscopy of mesenteric tissues, microscopy of liver tissue homogenates and Kato-Katz technique showed 86.61%, 87.16% and 97.27% sensitivities for detection of S. japonicum infections in wild mice, respectively. Conclusions Diverse etiological assays show various efficiencies for detection of S. japonicum infections in wild mice. Combination of microscopy of mouse liver tissues and microscopy of mesenteric tissues, and combination of microscopy of mouse liver tissues and microscopy of liver tissue homogenates are potential approaches for field detection of S. japonicum infections in wild mice.