Fea's muntjac (Muntiacus feae) is a critically conserved species in Thailand, with fewer than 3 captive breeding pairs, while the closely related red muntjac remains widespread. Red muntjac was recently reclassified into northern (M. vaginalis) and southern (M. muntjak) lineages, though their genomic distinctions are unresolved. This study aimed to generate a high-quality Fea's muntjac reference genome using hybrid sequencing and examine its relationships with other mammals, as well as southern red muntjac and northern red muntjac genomes available in NCBI. Genome-wide single nucleotide polymorphism (SNP) analysis via RADseq was used to assess population structure, genetic purity, and inbreeding among Fea's muntjac and red muntjac in Thailand. The Fea's muntjac genome measured 2.47 Gb and contained 26 901 protein-coding genes. Phylogenetic analyses suggested Fea's muntjac diverged earlier than expected, coinciding with climatic and geological shifts. Comparative genomics revealed expansions in olfactory and spermatogenesis-related gene families, suggesting adaptive evolution. Admixture analysis identified 1 Fea's muntjac-red muntjac F1 hybrid. Captive Fea's muntjacs showed high inbreeding, reflecting their restricted founder base, whereas red muntjacs exhibited greater diversity. All Thai red muntjacs belonged to northern red muntjac, and all southern red muntjac reference genomes closely resembled northern red muntjac. These findings provide essential genomic insights into Fea's muntjac and red muntjac, supporting conservation strategies and the long-term genetic management of these species.
Marek's disease virus (MDV) causes lymphomas and neurological disorders in chickens. Although vaccination largely controls outbreaks, highly virulent strains continue to emerge. The major MDV-encoded oncoprotein is Meq, functions as a transcription factor. Amino acid polymorphisms in Meq have been reported to influence virulence. Despite routine vaccination, MD still occurs sporadically in Japan. Japanese isolates harbour characteristic Meq polymorphisms, but their impact on MDV virulence remains unclear. We investigated the transcriptional regulation by Meq from Japanese isolates and evaluated the pathogenicity of recombinant MDV (rMDV) encoding Meq from the Japanese isolate Nr-c1. Nr-c1-Meq exhibited reduced transrepression and transactivation on viral gene promoters. An rMDV encoding Nr-c1-Meq (vNr-c1-Meq) induced lower mortality and tumourigenicity than an rMDV encoding Meq from the parental very virulent RB-1B strain (vRB-1B). vNr-c1-Meq did not cause visceral tumours or neurological disorders but resulted in distinct clinical signs, including open-mouth breathing. In lymphoid tissues from vNr-c1-Meq-infected chickens, a lower proportion of CD4+ T cells, the targets of MDV transformation, and lower viral loads were observed than those in vRB-1B-infected chickens. Histopathological examination revealed increased lymphocyte infiltration in bronchus-associated lymphoid tissues (BALT) in the vNr-c1-Meq group. Additionally, flow cytometric analysis showed elevated γδ T-cell proportions, which positively correlated with IFN-γ expression in vNr-c1-Meq-infected chickens and were linked to BALT hyperplasia. In comparison to the vRB-1B, vNr-c1-Meq infection resulted in attenuated disease progression and altered clinical signs. These findings suggest that Meq polymorphisms not only influence MD virulence but also clinical presentation.
The mammary circulatory system supports mammary growth and lactation by supplying oxygen and nutrients. Insulin-like growth factor 1 (IGF1) is essential for mammary gland development, yet its involvement in angiogenic regulation remains unclear. This study investigated whether IGF1 stimulates vascular endothelial growth factor (VEGF) production in mammary epithelial cells and explored the underlying signaling pathways. IGF1 increased VEGF mRNA expression in a bovine mammary epithelial cell line and in HC11 cells, and enhanced VEGF promoter activity and secretion in HC11 cells in a dose-dependent manner. Conditioned medium from IGF1-stimulated HC11 cells promoted tube formation in HUVECs, which was attenuated by a VEGFR inhibitor. IGF1 rapidly induced ERK1/2 and Akt phosphorylation, and inhibitors of these pathways suppressed VEGF secretion. These findings suggest that IGF1 upregulates VEGF via the MEK-ERK1/2 and PI3K-Akt pathways, thereby promoting mammary angiogenesis and contributing to mammary gland development and lactation efficiency.
Bovine adenovirus type 10 (BAdV-10) was isolated for the first time in Japan from a calf with severe hemorrhagic diarrhea at a farm in Gifu Prefecture. Histopathologically, lesions were mainly in the colon, with pseudomembrane formation accompanied by extensive fibrosis and viral inclusion bodies in the nuclei of vascular endothelial cells. The isolated virus showed cytopathic effect in bovine testicular cells and was genetically confirmed to be BAdV-10. Although the BAdV-10 gene was not detected in the rectal stools of cohabiting calves, an increase in antibody titers was observed. Involvement of BAdV-10 in lesion formation was suspected, but extensive fibrosis was not reported overseas. Further investigation is needed to clarify the prevalence and epidemiological significance of BAdV-10 in Japan.
