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Aquaculture industry has emerged as a rapidly expanding sector, contributing significantly to the economic growth of Vietnam. However, it has been challenged with disease outbreaks caused by various bacterial pathogens and the rise of antibiotic resistance. The uses of Bacillus species and their antimicrobial substances have been known as a promising alternative to antibiotics. This study was conducted to investigate biological characteristics and inhibitory activity of strain VNUA122 obtained from the gastrointestinal tract of common carp (Cyprinus carpio). The agar well diffusion assay was utilized to determine inhibitory activity against bacterial pathogens and extracellular enzyme production of the strain. As a result, strain VNUA122 exhibited high antagonistic effect on various aquatic animal pathogens including Pseudomonas aeruginosa, Aeromonas hydrophila, Vibrio parahaemolyticus, Staphylococcus aureus and Escherichia coli, recording inhibition zones of 15.33, 10.00, 7.00, 16.33 and 6,33 mm, respectively. Moreover, this strain was capable of secreting a wide range of hydrolytic enzymes, including amylase, protease, cellulase and chitinase. Proteinase K treatment confirmed the proteinaceous nature of the VNUA122 antimicrobial compounds. Based on the morphological, biochemical features as well as 16S rRNA gene sequence analysis, strain VNUA122 was identified as a member of the genus Bacillus. Regarding culture conditions, this strain grew optimally at 30oC, salt concentration of 0-2% and pH6-pH8, lactose and beef extract were the most suitable nutrient sources for its growth. These data demonstrate that Bacillus sp. strain VNUA122 is a potential biocontrol agent in aquaculture.

This study aimed to characterize the major milk components (fat, protein, and lactose) and quantify the effects of selected biological and environmental factors on milk composition of HF cows raised in the North Central region of Vietnam. A total of 220,118 test-day milk records from 19,192 cows collected through the monthly milk recording program on three farms over three years (2023-2025) were analyzed using descriptive statistics and linear mixed models. Effects of month in milk, parity, birth origin of cows (imported US-born cows vs. Vietnam-born offspring of imported HF parents), calving year, calving season, month of the year, and farm were evaluated. The average contents of milk fat, protein, and lactose were 3.75%, 3.21%, and 4.99%, respectively. Milk fat and protein contents declined during early lactation, and increased from mid-lactation onward, whereas lactose showed a slight decline as lactation progressed. First-parity cows produced milk with the highest fat and lactose contents, while second-parity cows had the highest protein content. Imported HF cows exhibited slightly lower fat content, but higher lactose content than HF cows born in Vietnam, while protein content did not differ significantly between the two groups. Calving year, calving season, and time of year all affected milk quality, though the level of influence varied across different parameters. Even though the farms belonged to the same management system, differences among them were still recorded. These findings may contribute to improving milk quality through appropriate herd management, nutritional strategies, and heat stress mitigation under tropical conditions.

  Banana anthracnose caused by Colletotrichum species complexes compromises global banana supply chains, requiring broad-spectrum biocontrol solutions. Building on previously published complete genome sequences and baseline antagonistic profiles, this study characterizes the broad-spectrum antifungal activity of Streptomyces parvulus VNUA74 (S. parvulus VNUA74)  against five Colletotrichum spp. causing banana anthracnose in Vietnam (C. musae VP01, C. siamense HY01, C. karstii NA03, C. fructicola DL01, and C. gloeosporioides HN04). Dual-culture assays on potato dextrose agar (PDA) revealed that S. parvulus VNUA74 suppressed pathogen mycelial growth, with inhibition rates ranging from 57.67 ± 2,28% to 86.75 ± 3.78%. The crude cell-free filtrate (CFF) inhibited mycelial growth by 53.87% ± 3.04% to 70.24% ± 1.01% and suppressed conidial germination by 82.23% ± 0.85% to 90.02% ± 1.11%. Microscopic analysis verified that the filtrate induced severe localized swelling, shortened interseptal distances, and caused bulbous hyphal distortions across all target strains. Volatile organic compounds (VOCs) and in planta detached tissue assays were executed across all five pathogens. The volatile fraction exhibited marginal suppressive capacity, yielding a maximum mycelial inhibition of 36.30 ± 3.39%. In contrast, in planta assays on detached host tissues demonstrated that the crude CFF consistently protected host tissues against all five pathogens. Disease suppression spanning 83.40% to 96.59% in vegetative leaves at 3 days post-inoculation (dpi) and 74.08% to 93.70% in postharvest fruits at 7 dpi. This study establishes an empirical foundation for profiling target metabolites of S. parvulus VNUA74 for sustainable banana anthracnose management.

Despite growing emphasis on digital transformation in rural development, empirical evidence on gender disparities in digital understanding and adoption in Vietnam remains limited. This study examines gender-based differences and the determinants of digital technology adoption capacity among 195 rural households in Ninh Binh province. Using parametric and non-parametric tests alongside multiple linear regression models, the study identifies significant gender gaps, with women exhibiting lower levels of digital understanding and application use than men. Gender remains a significant predictor of both outcomes after controlling for socio-demographic and economic factors. Age negatively influences digital understanding and adoption, whereas education and income positively affect adoption capacity. Notably, digital understanding strongly predicts adoption, underscoring its mediating role in translating knowledge into usage. Ownership of internet-connected devices further supports digital engagement, while cooperative membership and digital information provision show no significant effects. The findings highlight the multidimensional nature of rural digital inequality and underscore the need for gender-responsive training, enhanced digital literacy initiatives, improved digital infrastructure access, and institutional reform to foster inclusive digital development in Vietnam.