Bangladesh Agricultural University

In aquatic ecosystems, the incidence of Vibrio spp. is rising continually due to changes in water parameters. The study was undertaken to assess the incidence of Vibrio spp. in shrimp farms relative to water parameters and to perform their molecular detection. Maintaining three replications of each sample, overall, 360 shrimp, 360 water, and 360 sediments were randomly collected from the experimental units of 30 ponds in Khulna and Satkhira districts in each of the rainy and winter seasons. Temperature, ammonium, nitrite, pH, iron, and salinity were measured from water samples. The groEL gene of Vibrio cholerae, and toxR, trh, and tdh genes of Vibrio parahaemolyticus were identified through real-time polymerase chain reaction assay. Shrimp showed the highest mean total Vibrio spp. count (9.39 ± 0.34 log CFU/mL) in the rainy season. In the rainy season, shrimp represented 42.5%, water 17.5%, and sediment 19.16% Vibrio spp., whereas in the winter season, these were 38.33%, 14.16%, and 15.83%, respectively. Temperature and pH were at the highest average levels in the rainy and winter seasons, respectively. There was no significant relation between the incidence of Vibrio spp. and water parameters, except ammonium in the winter season. Here, 48.02% (85/177) isolates were positive for V. cholerae, 51.97% (92/177) for V. parahaemolyticus, 15.21% (14/92) for the trh gene, and 6.52% (6/92) for the tdh gene. None of the relations between water parameters and trh-positive V. parahaemolyticus was significant, except pH in the rainy season. The occurrence of Vibrio spp. in shrimp farms should be a burning issue for sustainable production.

Achieving low-emission prawn farming requires precise quantification of in-pond greenhouse gas (GHG) emissions and strategies that reduce environmental costs without compromising productivity. Using an experimental setup, we analysed 5832 gas samples to determine the seasonal and diurnal dynamics of CO2, CH4, and N2O fluxes across non-aquaculture, prawn monoculture, prawn polyculture with either carp, plant, or snail, and an integrated multi-trophic aquaculture (IMTA). Non-aquaculture ponds emitted 46.33kg CO2e/ha/month, whereas polyculture ponds emitted 96.16kg CO2e/ha/month. IMTA delivered the highest biological yields, while reducing emission intensities by 40% and 20-25% compared to monoculture and polyculture, respectively. Monoculture showed the highest food and nutritional emission intensities and the largest economic footprint. Contrarily, IMTA achieved the highest revenue with the lowest economic footprint. A generalized additive model revealed that prawn biomass accounted for 74% of total emissions, while snail and water spinach substantially mitigated fluxes through waste utilization, nutrient recycling, carbon sequestration, and oxygenation. These advantages of IMTA illustrate its potential as a low-emission aquaculture approach that reconciles profitability with environmental stewardship.

Maize (Zea mays L.) is one of the major grain crops worldwide that is particularly vulnerable to waterlogging (WL) stress. Glutathione (GSH) and nitric oxide (NO) are known to protect plants from a variety of abiotic stresses; however, their potential for improving WL tolerance in maize remains unexplored. The present study examined the impact of exogenously applied GSH and NO on maize plants exposed to WL-stress. Our findings revealed that GSH + NO-treated waterlogged maize plants grew better and produced more biomass than only WL-stressed plants. The improved performance of GSH + NO-sprayed WL-stressed maize seedlings was supported by the increased root dry and fresh weight, shoot length, shoot dry and fresh weight, chlorophyll a, chlorophyll b, and carotenoid content. Exogenous GSH and NO treatments significantly enhanced the amounts of leaf proline, leaf soluble sugars, and total protein in maize seedlings, suggesting adaptive metabolic reprogramming under stress. The increased malondialdehyde (MDA) levels and accumulation of hydrogen peroxide (H2O2) in maize leaves and roots revealed that WL caused significant oxidative damage. Exogenous GSH, NO individually, and combinedly significantly decreased total H2O2 and MDA contents in both leaves and roots. Exogenous GSH and NO reduced oxidative stress by increasing peroxidase activity, ascorbic acid, and anthocyanin content in maize leaf and root tissues. Our findings emphasize the possible relevance of GSH and NO, simultaneously and individually, in enhancing adaptive mechanisms in maize seedlings for reducing WL-induced damage. Although the GSH + NO-mediated approach shows promise for mitigating WL-stress in maize under controlled conditions, further field-based investigations are required to validate its practical applicability.

Canine hepatocellular carcinoma (HCC) requires further molecular characterization to identify diagnostic and therapeutic targets, and to establish whether dogs with this condition can model the human disease. Accordingly, we aimed to identify differentially expressed genes (DEGs) in canine HCC and evaluate cross-species transcriptomic dysregulation in canine and human HCC. Liver tissue samples from three dogs with HCC and three healthy dogs were subjected to next-generation sequencing, followed by RT-qPCR validation. Identified DEGs were then targeted in bioinformatics analyses (pathway enrichment, protein-protein interaction network, and hub gene analyses) for molecular characterization and comparison with human HCC datasets. We identified 975 DEGs (upregulated: 604; and downregulated: 371). Extracellular matrix-receptor interaction, focal adhesion, cell adhesion molecule, PI3K/Akt signaling, and cytokine/chemokine-related pathways were enriched. C1R, APOC3, C1QA, APOA1, C1QB, ACTG1, C1QC, CRP, ANXA5, and ANXA2 were identified as hub genes. Canine and human HCCs share 118 DEGs, highlighting conserved alterations in metabolic pathways, PI3K-Akt signaling, focal adhesion, and PPAR signaling pathways. Based on human HCC data, SPP1, NQO1, RRM2, APOA1, APOC3, ALDOB, and IGF1 were identified as prognosticators indicating poor overall survival. This study presents the first cross-species transcriptomic analysis of canine HCC, revealing significant molecular resemblances to human HCC, indicating it may be a promising comparative model for studying tumor biology, drug responses, and novel therapeutic interventions.

ABSTRACT Most of the rivers and waterbodies in the Ganges–Brahmaputra–Meghna basin in Bangladesh are continually losing ecological integrity due to low water flow and reduced connectivity. This research combines quantitative hydrological indicators with local knowledge to identify basin‐specific barriers and guide adaptive river and ecosystem management. The analysis focused on hydrological aspects, including trends in extreme river stage values, environmental flow (e‐flow) stages, seasonal fluctuations, connectivity and the impacts of hydraulic structures, using daily river stage data from 19 gauging stations collected between 1998 and 2017, along with qualitative data gathered through the participatory rural appraisal approach. For the e‐flow analysis, the dataset was divided into two periods (1998–2007 and 2008–2017) and categorized into yearly low‐flow, high‐flow and intermediate‐flow seasons. Most rivers exhibited significant declining trends, with annual stage fluctuations ranging from 1.3 to 12.3 m. The Little Jamuna River showed the highest river stage declines of up to 25.5 cm/year. About 80% of rivers failed to maintain e‐flow thresholds, with flow deficits ranging from 5% to 80% of days, indicating increasing ecological stress. Smaller rivers experienced sharper dry‐season declines and weaker connectivity than major rivers, primarily due to intensive irrigation, reduced upstream inflow and localized sedimentation. Water levels in the tidal Meghna River showed a slight upward trend, possibly in response to climate change–induced sea‐level rise. The study emphasizes the need for ecosystem‐based planning, improved regulator operations, rainwater harvesting, regulated groundwater abstraction and the reconnection of rivers to adjacent wetlands to restore ecological integrity.