Son La heirloom chrysanthemum (Chrysanthemum sp.) is a woody ornamental plant with a bushy growth habit, possessing high ornamental and economic value, and is suitable for pot cultivation and bonsai shaping. However, conventional propagation methods for this cultivar are limited in terms of multiplication rate and plantlet quality. This study aimed to induce in vitro shoot proliferation and rooting of Son La heirloom chrysanthemum and to evaluate the potential replacement of agar with several inorganic materials during the rooting stage. The experiment was conducted on Murashige and Skoog (MS) medium supplemented with 30 g/L sucrose through two stages. In the shoot proliferation stage, stem segments were cultured on MS medium solidified with 8 g/L agar under four treatments: 6-benzylaminopurine (BAP) at 1.5 mg/L, potato extract 10% (w/v), carrot extract 10% (w/v), and coconut water 10% (v/v). After 42 days of culture, the medium supplemented with BAP at 1.5 mg/L produced the highest number of shoots and leaves (5.01 shoots per explant and 33.3 leaves per explant), whereas coconut water at 10% significantly enhanced shoot height (4.62 cm). In the rooting stage, in vitro stem segments were cultured on agar 8 g/L (control) and on inorganic substrates including red lava, black lava, masato, and perlite (30 g per vessel combined with 30 mL liquid MS medium supplemented with 1 mg/L IBA). After 42 days, perlite achieved a rooting percentage of 93%, comparable to agar, while producing significantly longer roots (8.45 cm). Overall, perlite shows strong potential as an alternative to agar in the in vitro rooting stage of Son La heirloom chrysanthemum, contributing to improved plantlet quality for production purposes.

The study aimed to evaluate the effects of different varieties on the growth, yield, and quality of kale grown on coconut coir substrate in net house conditions at Can Tho University. The experiment was arranged in a completely randomized design comprising five treatments associated with five kale varieties: (1) Rong Bien Xanh, (2) Rong Bien Tim, (3) Xoan Xanh, (4) Xoan Tim, and (5) Xoan Xanh Viet. Each treatment was replicated six times. The results showed significant differences among cultivars for growth attributes and production quality. The Xoan Xanh kale showed superior performance with a leaf length of 25 cm, a stem diameter of 14.7 mm, an average leaf weight of 11.2 g, a total leaf weight of 819 g/plant, and the highest vitamin C content at 39 mg/100 g. The Rong Bien Xanh kale had the highest number of leaves (84 leaves/plant) and the widest leaves (15.6 cm), yet it recorded the lowest vitamin C content (26 mg/100 g). Meanwhile, the Xoan Tim kale had the lowest yield, producing only 45.7 leaves/plant and a total leaf weight of 443 g/plant. The Xoan Xanh kale exhibited appropriateness in net house environments owing to its remarkable growth traits, substantial yield, and superior quality relative to the other varieties, making it advisable for commercial cultivation.

Poor evergreen broadleaf natural forests constitute an important component of tropical forest ecosystems, playing a critical role in maintaining biodiversity and providing a foundation for sustainable forest restoration. This study aimed to assess stand structure, natural regeneration characteristics, and tree species diversity of poor evergreen broadleaf natural forests on lowland hills in Ninh Dien, Hoa Hoi, and Phuoc Vinh communes, Tay Ninh Province, as a scientific basis for forest management and restoration. A total of 47 tree species belonging to 24 families were recorded, with Dipterocarpaceae as the dominant family; Fabaceae, Sapindaceae, Chrysobalanaceae, and Malvaceae also contributed substantially to the stand composition. Five species of ecological importance were identified, including Vatica odorata, Hopea ferrea, Nephelium chryseum, Parinari annamensis, and Dipterocarpus costatus. The mean stand density was 516 trees/ ha, with an average growing stock of 84.5 m³/ha. Diameter distribution exhibited a left-skewed unimodal pattern described by the Weibull function, while height distribution followed a normal distribution, indicating an intermediate post-disturbance recovery stage with a relatively simple stand structure. Natural regeneration was abundant, with a density of 4,288 individuals/ha, dominated by seed-origin regeneration and primarily composed of native species. Shannon-Wiener diversity and Pielou evenness indices indicated a relatively balanced species composition without absolute dominance. Based on these findings, the study proposes silvicultural measures, including assisted natural regeneration, enrichment planting with native species, and long-term monitoring of forest dynamics, contributing to the restoration and sustainable management of natural forests in the study area.

This study aimed to estimate genetic parameters for growth and survival traits in the Portuguese oyster (Crassostrea angulata) G1 breeding generation reared under monsoon tropical conditions at Long Son, Vung Tau. A total of 8,000 individuals from 80 families (44 full-sib and 36 half-sib) were evaluated for growth over 183 - 207 days. Genetic parameters were estimated using an individual linear mixed model implemented in ASReml 4.2. Heritability was moderate to high for growth traits (0.183 - 0.607) and moderate for survival (0.276). Strong positive genetic correlations (0.70 - 0.91) were observed among growth traits (body weight, shell height, shell length, and shell width), while weak negative correlations (-0.11 to -0.09; P > 0.05) were found between growth and survival. The mean estimated breeding value (EBV) of the selected group was 10.36 g for body weight, with selection responses of 19.83% for body weight and 35.27% for survival rate when traits were selected separately. These results demonstrate the clear potential for genetic improvement of Portuguese oyster traits under tropical monsoon conditions. The study also recommends expanding growth evaluations across multiple farming environments in southern Vietnam to estimate genotype × environment interactions, thereby supporting the development of a sustainable breeding program for C. angulata in the future.

This study evaluated the growth performance, survival rate, and prevalence of common diseases in two selectively bred strains of striped catfish (Pangasianodon hypophthalmus): a fast-growth strain (G4-TT) derived from a selective breeding program and a strain selected for resistance to Bacillary Necrosis of Pangasius (BNP) (G1-KB), in comparison with a commercial control strain. The three strains were co-cultured in 15-m³ cement tanks separated by mesh partitions, with three replicates. After 60 days of nursing, significant differences in body weight, total length, and survival rate were observed among the strains (P < 0.05). The G4-TT strain exhibited the highest growth performance and survival rate (5.34 g, 89.8 mm, and 43.6%, respectively), followed by the G1-KB disease-resistant strain (4.0 g, 83.2 mm, and 37.3%), whereas the commercial strain showed the lowest values (2.89 g, 75.7 mm, and 18.4%). All strains were infected with Trichodina spp. and Aeromonas spp., but only at mild levels, without clear clinical signs. The results indicate that during the early life stage (from fry to 60 days old), both selectively bred strains show higher growth performance and survival rates compared with the commercial strain.

The present study investigated the growth characteristics, feeding habits, and reproductive biology of the wild Siamese fighting fish population (Betta sp.) distributed in Duc Hue district, Long An province, Vietnam. The study was conducted over four months, covering August - September 2024 (rainy season) and March - April 2025 (dry season), with samples collected once per month. Results indicated that Betta sp. was found in all communes of the Duc Hue district except Dong Thanh town, where habitat alteration due to urbanization may have contributed to local population decline or disappearance. The length-weight relationship was established as W = 0.018 L2.587 (R2 = 0.878). The regression coefficient (b = 2.587) was lower than 3, indicating negative allometric growth, suggesting a faster increase in length than in body weight. The mean relative length of the gut (RLG) was 0.42 ± 0.01, confirming its carnivorous feeding habit. Feeding analysis showed active carnivorous behavior, with approximately 80 - 92% of specimens exhibiting stomach fullness levels of ≥ 2. Feeding intensity was significantly higher during the wet season (χ2 = 28.293, P = 0.005). Reproductive indices showed seasonal variation: mean gonadosomatic index (GSI) peaked during the wet season (females: 6.41 - 7.00%; males: 5.04 - 5.06%), indicating higher reproductive readiness in this period. Mean absolute fecundity (AFe) was estimated at 255 ± 29 eggs per female, and mean relative fecundity (RFe) was 531 ± 56 eggs per gram of female body weight. This study provides essential biological baseline data for the management and conservation of Betta sp. resources in the local area.

The objective of this study was to evaluate the effect of alkaline treated rice straw, combined with urea and quicklime powder, on the methane emission reduction in vitro in daily diets at the Center for Research and Technology Transfer, Nong Lam University, Ho Chi Minh City, Vietnam. The study was conducted using a single factor completely randomized design, with rice straw treatment as the experimental factor, including (1) a control diet currently applied at the farm containing untreated rice straw (UTRS) and (2) a treatment diet in which untreated rice straw was replaced with alkaline-treated rice straw (ATRS). The results showed that alkaline treatment improved the nutritional values (CP, NDF, ADF, GE, DE, and ME) of rice straw. The total volume of gases produced from the control diet was 215.50 mL per incubation bottle at 12 h and 415.00 mL per incubation bottle at 24 h, which were significantly higher than those from the experimental treatment (171.33 and 370.83 mL per incubation bottle, respectively) (P < 0.001). The volume of methane produced at 12 and 24 h in the UTRS (23.70 and 56.02 mL per incubation bottle, respectively) was significantly higher than that in the ATRS (16.28 and 41.46 mL per incubation bottle, respectively) (P < 0.001). The ratios and volume of methane produced per g of dry matter of feed at 12 and 24 h were also significantly lower in the ATRS (P < 0.001). In brief, alkalization of rice straw with urea and quicklime powder in the daily diets of cattle appears to improve the nutritional value and digestibility of rice straw, as well as reduce methane emissions in vitro, contributing to the development of a sustainable cattle industry in tropical regions.

This study investigated the effects of supplementing farm-used antibiotics (AB) and a Vietnamese herbal product (TMV) in the diets of Anh Dao ducks. A total of 1,200 one-day-old ducks were randomly allocated to four experimental groups with two factors: AB and TMV (group 1: No AB and 0 g TMV; group 2: No AB and 3 g TMV; group 3: With AB and 0 g TMV; group 4: With AB and 3 g TMV). Ducks were raised until 35 days of age. Results showed that survival rates were relatively high in all groups (> 97%). The weekly live body weight of ducks in groups receiving AB or TMV was significantly higher than that of group 1 (P < 0.001). Ducks in groups 3 and 4 also had higher live body weights than those in group 2 (P < 0.05). Additionally, there was an AB x TMV interaction for the live body weight (P < 0.001). Feed intake and body weight gain in groups 2, 3, and 4 were all higher than those in group 1, especially during weeks 3, 4, and 5 (P < 0.05). There were no significant differences in feed conversion ratio among groups (P > 0.05). At 35 days of age, AB, TMV, or their interaction did not affect the flock uniformity of Anh Dao ducks (P > 0.05). Briefly, dietary supplementation of AB and TMV, either individually or in combination, had positive effects on feed intake, growth rate, and live body weight in Anh Dao ducks.

Lumpy skin disease (LSD) is a significant infectious disease affecting cattle and buffaloes, causing substantial losses to the livestock industry. This study analyzed the progression of LSD outbreaks in Quang Binh province from 2021 to 2024 using epidemiological data and GIS (geographic information system) technology to assess disease distribution. Collected data were processed using Microsoft Excel 2019, descriptive statistical analysis was conducted with SPSS (IBM, 2020), and QGIS (an open-source Geographic Information System software) was employed for visualization to identify high-risk areas. The results indicated that LSD outbreaks varied across districts, with Quang Trach, Quang Ninh, and Tuyen Hoa identified as the highest-risk areas due to high livestock density. Quang Trach district and Ba Don town recorded a gradual decline in disease incidence from 2021 to 2024, attributed to effective control measures such as vaccination and strict disease management. Meanwhile, other locations, including Bo Trach, Le Thuy, and Dong Hoi, also reported cases, though they were not classified as high-risk areas. This study highlights the importance of applying QGIS technology in disease monitoring, aiding authorities in developing appropriate control strategies. The creation of risk maps based on livestock density and epidemiological data enhances the effectiveness of future LSD prevention and control efforts.

This study presents a green and sustainable route for synthesizing silver nanoparticles (AgNPs) using mangosteen peel extract, which served as both a reducing and a stabilizing agent. The synthesis process was optimized by investigating key parameters, including temperature, reaction time, AgNO₃ concentration, and the Ag+ solution-to-extract ratio. The formation of AgNPs was confirmed by UV-Vis spectroscopy, while XRD (X-ray diffraction), HR TEM (High-resolution transmission electron microscopy), and SAED (Selected area electron diffraction) analyses revealed that the nanoparticles were spherical, well-dispersed, crystalline face centered cubic structures with an average size of 16.2 ± 4.3 nm. The AgNPs exhibited exceptional catalytic activity in the sodium borohydride (NaBH₄) reduction of p-nitrophenol (PNP), achieving a conversion efficiency of > 95% within just 2 minutes. This catalytic reaction followed pseudo-first-order kinetics with a reaction rate constant (k = 0.815/min). Furthermore, the AgNPs demonstrated strong antibacterial activity against Escherichia coli and Salmonella typhi, evidenced by an inhibition zone of approximately 15 mm, a minimum inhibitory concentration (MIC) of 3.04 mg/L, and a minimum bactericidal concentration (MBC) of 6.08 mg/L. These findings not only highlight the potential of plant extracts for the green synthesis of AgNPs but also underscore the promising application of this nanomaterial in environmental remediation and biomedical fields.