Tropical aquaculture systems require sustainable feed alternatives to address rising ingredient costs and utilize locally available agricultural residues. This study evaluated the effects of replacing rice polish with fermented maize leaf meal (MLM) on growth performance, blood parameters, and body composition of grass carp (Ctenopharyngodon idella). Six iso-nitrogenous diets (30

This study investigated the immunomodulatory effects of dietary pineapple peel powder (PPP) supplementation in Labeo rohita fingerlings (15.2 ± 0.3 g) through a 60 d feeding trial followed by a 15 d Aeromonas veronii infection challenge. Processing 1 kg of pineapple fruit generates approximately 30-35% waste, primarily peels, containing bioactive compounds including bromelain enzyme. Using a completely randomized design, 300 fingerlings were distributed into 5 treatment groups in triplicate: Control (0%), T1 (2%), T2 (4%), T3 (6%), and T4 (8%) PPP supplementation. Immunological, haematological, biochemical, and antioxidant parameters were assessed at 0, 15, 30, and 60 d, with bacterial challenge conducted on Day 61 and post-infection (PI) sampling at 7 and 15 d PI. Fish fed 6% PPP (T3) exhibited significantly enhanced immunological parameters, with serum lysozyme activity reaching 185.6 ± 8.4 unit ml-1 compared to 112.3 ± 5.7 unit ml-1 in control. Significant improvements occurred in haematological indices (red blood cells, white blood cells, hemoglobin, hematocrit), serum proteins (total protein, albumin, globulin), and antioxidant enzyme activities (superoxide dismutase, catalase, glutathione peroxidase). Following A. veronii challenge (1×107 CFU ml-1; 0.1 ml fish-1), T3 demonstrated the highest survival rate (82.5 ± 3.4%) compared to control (45.6 ± 2.7%). Growth performance also improved significantly, with specific growth rate (2.84 ± 0.12% vs. 2.15 ± 0.09% d-1) and feed conversion ratio (1.42 ± 0.06 vs. 1.85 ± 0.08) both enhanced in T3 compared to control. These results demonstrate that 6% PPP supplementation optimally enhances immunophysiological parameters, disease resistance, and growth performance in L. rohita, highlighting its potential as a natural immunostimulant in sustainable aquaculture health management.

Background Motile Aeromonas Septicaemia (MAS) is a common bacterial fish disease caused by opportunistic microorganisms Aeromonas hydrophila, posing a threat to aquatic and terrestrial animals, including humans. The standard treatment for MAS has been antibiotics, but their use has raised concerns due to potential harm to the host's environment and water quality. In response, researchers are increasingly turning to phage therapy as a promising alternative. Bacteriophage (phage), a virus that infects and replicates within bacteria, offers a targeted approach to controlling bacterial growth. In the present study, the Aeromonas phage GomatiRiver_11 was isolated from various water bodies in Tripura, India. This marked the first time this phage had been identified. The phage's complete genome sequence was determined to be 167,776 base pairs containing 289 Open Reading Frames (ORFs). Phylogenetic analysis revealed its close relation to Aeromonas phage SW69-9 (KY290958.1). Based on the ICTV 2022 taxonomy update, it was confirmed that the phage belongs to the class Caudoviricetes based on tailed bacterial viruses with icosahedral capsids. The newfound understanding of Aeromonas phage GomatiRiver_11 holds significant promise for phage therapy against MAS in fish species infected with A. hydrophila found in water bodies. By harnessing the phage's targeting abilities toward A. hydrophila, researchers can aim to develop effective and eco-friendly approaches to combat this bacterial diseases and safeguard aquatic ecosystems by diminishing the rise of antimicrobial resistance.

This study examined length-weight relationships and condition factors of the endemic dwarf snakehead Channa lipor from its type locality in Meghalaya, India. Seventy-six specimens were collected using non-invasive hand netting from the Umraling River during a twelve-month survey (May 2019–April 2020). Morphometric measurements were recorded using digital instruments, and data analysis employed logarithmic transformation and linear regression modeling. Specimens ranged 4.9–11.6 cm in total length and 1.09–13.39 g in weight. Analysis revealed negative allometric growth (W = 0.011233L2.920, r2 = 0.962, p < 0.001). Mean condition factors were: Fulton’s K = 0.956 ± 0.110, relative Kn = 1.007 ± 0.113, and modified Km = 1.131 ± 0.127. Specimens in the 6–8 cm size class exhibited optimal condition values, indicating healthy population status in this hill stream environment.

Saprolegniasis in fish, caused by oomycete water molds of the genus Saprolegnia, poses a significant threat to aquaculture operations, particularly in cold-water environments that favour the proliferation of these opportunistic pathogens. This study evaluated the therapeutic efficacy of formalin bath treatments against Saprolegnia infections in Puntius gonionotus, an emerging aquaculture species, under the mid-hill conditions of Umiam, Meghalaya. Experimental infection was established by cohabiting partially infected fish with moribund conspecifics and inducing dermal abrasion to achieve uniform, full-body infection. Fully infected fish were then subjected to formalin immersion at 0 ppm (control), 50 ppm, 100 ppm, and 150 ppm for 30 or 60 seconds, administered on alternate days over five days to allow recovery between treatments and minimize chemical stress. Infection severity was scored on a standardised scale encompassing clinical signs, behavioural changes, integumentary lesions, ocular pathology, mucus depletion, and anorexia. Two-way analysis of variance revealed significant main effects of formalin dose and treatment duration, as well as their interaction, on infection intensity reduction. The highest dose of 150 ppm applied for 60 seconds produced the greatest reduction in infection severity (83.3%). These findings support formalin chemotherapy as an effective disease management intervention for hill aquaculture operations.

This study evaluated the potential of paddy-fish integration in Tripura, focusing on three districts: South Tripura, West Tripura, and Gomati. Using a comparative design with control (rice monoculture, n = 30) and treatment (paddy-fish integration, n = 30) plots, we collected data from 60 farms over a 3-year period (2020-2022) through stratified random sampling. Farm surveys, field measurements, and soil analysis were employed to assess productivity, yields, economic viability, and soil quality impacts. The size of paddy plots ranged from 500 to 2000 m², with farmers cultivating air-breathing fish and small indigenous species. Statistical analysis revealed that paddy-fish integration significantly increased paddy yields by 14.3% and produced an additional 350±75 kg ha-1 of fish, resulting in a 69.5% to 107.2% higher benefit-cost ratio (2.27±0.32 vs. 1.20±0.05) compared to rice monoculture. Both rotational and concurrent farming systems showed economic viability, with the rotational system demonstrating slightly higher individual yields. Soil fertility parameters, including organic carbon, available NPK, and pH, improved significantly in integrated systems (p<0.05). This research confirms that paddy-fish integration is an economically viable and environmentally sustainable farming system for Tripura, offering significant productivity gains and improved farmer incomes while enhancing soil health for long-term agricultural sustainability.

The ornamental fish industry faces challenges in enhancing fish coloration and health while simultaneously addressing the growing concern of agricultural waste management. This study investigates the potential of fruit and vegetable peels as feed additives for improving coloration, immune-related parameters, and growth in Banded gourami (Trichogaster fasciata), with potential for waste valorization in the food production chain. Over a 12-week feeding trial, the effects of banana peel (BP), apple peel (AP), carrot peel (CP), and beetroot peel (BRP) supplements at 5

This study evaluated three feeding strategies in composite fish culture (CFC) systems in tribal villages of Tripura to enhance aquaculture productivity. Fifteen farmer ponds (0.08 ha each) were utilized with three treatments in five replicates: conventional feed (CF: rice polish and mustard oil cake 1:1), floating pelleted feed (FPF), and combination feeding (COM: CF and FPF). Indian major carps were stocked at 10,000 fingerlings/ha with species composition of Catla catla (40%), Labeo rohita (30%), and Cirrhinus mrigala (30%). Feeding rates were progressively reduced from 5% of fish biomass in initial two months to 1% in final two months over a 10-month culture period. Fish production was significantly higher (P<0.05) in COM treatment (4.2±0.12 MT/ha) followed by FPF (3.8±0.08 MT/ha) and CF (3.2±0.06 MT/ha). Feed conversion ratio was most efficient in COM (2.1±0.05) compared to FPF (2.4±0.06) and CF (3.1±0.08). Economic analysis revealed highest net profit in COM treatment (₹4,49,000±18,750 per hectare) with benefit-cost ratio of 2.6±0.07. The combination feeding strategy demonstrated superior performance by optimizing feed utilization efficiency while maintaining cost-effectiveness. These findings suggest that alternating feeding regimen can significantly enhance fish productivity in tribal aquaculture systems, providing a sustainable approach for livelihood improvement in northeastern India.

This study evaluated an integrated multi-trophic aquaculture (IMTA) system involving common carp (Cyprinus carpio), freshwater mussels (Lamellidens marginalis), and water lily (Nymphaea nouchali) over a 90-day period in outdoor cement tanks (1 m × 1 m × 1 m = 1 m³ each). Growth performance, physiological responses, ecosystem services, and system efficiency were compared across four treatments: carp monoculture as the control (T1), carp with mussels (T2), carp with water lily (T3), and the full IMTA system (T4). The full IMTA system demonstrated superior performance with significantly higher specific growth rate (2.87 ± 0.12

This study investigated seasonal variations in thenutritional composition of Notopterus notopterus, apotential species for aquaculture diversification inIndia. Samples were collected across four seasons in Tripura, India, and analyzed for proximate composition and mineral content. Significant seasonal variations were observed in protein, lipid, ash, moisture content, and mineral composition (p<0.05). Protein content peaked during the pre-monsoon season (18.2±0.3%), while the highest lipid content was observed in winter (8.5±0.2%). Calcium and phosphorus levels were highest during the monsoon season (890±18 mg/100g and 320±7 mg/100g, respectively). The results indicate that N. notopterus can be marketed as a high-quality protein source with significant micronutrient content, particularly during the pre-monsoon and monsoon seasons. These findings have implications for consumer choice, market positioning, and addressing food security in the region, emphasizing N. notopterus’ potential for sustainable aquaculture diversification and its suitability for small-scale farmers as both a nutritional resource and a complementary species to income-generating crops.

The oomycete water mold Saprolegnia parasitica poses a considerable threat to the global aquaculture industry, leading to substantial economic losses. This study aimed to investigate the effects of experimental S. parasitica challenge on key immunological, biochemical, and hematological parameters, as well as disease resistance, in fingerlings of Labeo rohita, an important freshwater carp species farmed across Southeast Asia. The study used a strain of S. parasitica isolated from L. rohita to challenge healthy juveniles (10.2 ± 2.1g) through different infection routes such as injection, cohabitation, and immersion exposure. Analyses of blood parameters on days 15, 30, and 45 post-infection revealed significant changes (P≤0.05), including increased blood glucose, decreased serum protein, albumin, and lysozyme activity, and variable serum bactericidal activity in infected fish. Infected fish also showed reduced hemoglobin concentration and erythrocyte counts compared to uninfected controls, leading to a mortality rate of about 55 % by day 45 post-infection. These findings suggest that S. parasitica infection can impair immune function in L. rohita fingerlings, potentially hindering the growth of the aquaculture industry reliant on this species. Future research should focus on identifying genetic and environmental factors influencing disease susceptibility, evaluating preventive and therapeutic measures, and exploring associated histopathology.

Forest-dependent communities in India, particularly in the Northeast region, face significant socio-economic challenges while possessing vast untapped aquatic resources. This study investigated the environmental sustainability of varying stocking densities (5–20 fish/m3) of Indian major carp Catla catla in eco-friendly bamboo cages within a forest water body in Tripura, Northeast India, intending to develop low-cost aquaculture solutions for forest dwellers. Water quality parameters, stress biomarkers, and ecosystem responses were monitored over 6 months. Results demonstrated optimal environmental and economic sustainability at 15 fish/m3, maintaining acceptable water quality (DO 5.6 ± 0.6 mg/L, ammonia-N 0.28 ± 0.04 mg/L) while maximizing production efficiency (survival 86.8 ± 2.1

AbstractThe study aimed to evaluate the effectiveness of feed-based aquaculture (FBA) in enhancing fish productivity in an adivasi village in Tripura, Northeast India, under the Schedule Tribe Component (STC). Six ponds managed by farmers, each measuring 0.08 ha and 1-1.5 m in depth, were utilized to compare two types of feed: floating feed (FF) and conventional feed (CF), made from a 1:1 mixture of rice bran and mustard oil cake, with community participation. The ponds were stocked with Catla (40%), Rohu (30%), and Mrigal (30%) at a stocking density of 10,000 fish per hectare. Fish were fed daily at 2 per cent of their biomass. Over six months study period, monthly monitoring of water quality parameters showed no significant fluctuations. At the end of the study, fish growth assessment revealed that Catla and Rohu exhibited better weight gain (P=0.05) with FF, while Mrigal performed better (P=0.05) with CF. FF also resulted in higher fish survival rates and improved feed conversion ratios (P=0.05). Total fish production was significantly higher (P=0.05) with FF (4052 kg/ha) compared to CF (3520 kg/ha), indicating the profitability of FBA with FF. The study concluded that FBA, whether using FF or CF, can enhance fish productivity. FF is highly recommended for increased production in adivasi villages. The participatory approach used in the study facilitated community mobilization and empowerment. Further participatory technology assessment and adoption are recommended for sustainable aquaculture development in underprivileged areas.

This study evaluated white turmeric (Curcuma zedoaria) as a sustainable feed additive alternative to common turmeric (C. longa) for enhancing disease resistance in Labeo rohita against Argulus siamensis infection. Juvenile L. rohita (15.8 ± 1.9 g) were divided into four treatment groups (n = 60 per group): (1) Control (commercial feed), (2) common turmeric-supplemented feed (1% w/w), (3) white turmeric-supplemented feed (1% w/w), and (4) combined turmeric-supplemented feed (0.5% common +0.5% white turmeric). Fish were fed experimental diets for 45 days before challenge with A. siamensis (10 parasites/fish), followed by 15 days of post-challenge monitoring (total experimental period: 60 days). Samples were collected on days 0, 15, 30, and 45 of the feeding phase, and on days 7 and 15 of the post-challenge phase. Results showed that turmeric supplementation significantly enhanced growth performance, haematological parameters (RBC, haemoglobin, haematocrit), immunological responses (lysozyme, respiratory burst, complement activities), and antioxidant status (SOD, CAT, MDA) compared to control. Post-challenge, turmeric-supplemented groups exhibited reduced parasite load and higher survival rates (Combined: 92%, common turmeric: 85%, White turmeric: 82%, Control: 68%). While common turmeric performed slightly better than white turmeric when used alone, the combined treatment showed superior efficacy in all parameters measured. These findings suggest that combining both turmeric species provides optimal benefits, while white turmeric can serve as a partial substitute for common turmeric in fish feed formulations when resource sustainability is a priority, thus helping to reduce competition with human food resources.

This study investigated common carp cage culture at four stocking densities (20, 40, 60, and 80 fish/m3) in a forest water body in Tripura, Northeast India, from June to November 2020. Twelve 1m3 cages with iron netting were arranged in a completely randomized design with three replicates per treatment. Results showed that 60 fish/m3 provided optimal balance between production and ecosystem health, yielding maximum biomass (12.2 ± 0.8 kg/cage) with 92.6

Wetland ecosystems are vital for global carbon sequestration, yet floating biomass formations (phumdi) remain understudied despite their unique ecological characteristics. This research presents the first comprehensive comparative analysis of carbon sequestration across three wetland types in Manipur, Northeast India: Pumlen Pat (open wetland, 8697.13 ha), Lamphel Pat (closed urban wetland, 587.8 ha), and Zaimeng Pat (closed hilly wetland, 4.42 ha). The 2-year study (2022–2023) employed seasonal sampling across 26 stations using standardized quadrat-based harvest methods, separating above-water and below-water biomass components. Carbon quantification utilized TIC-TOC analysis of oven-dried samples and included dissolved carbon measurements in water columns. Results revealed significant variations in carbon storage capacity, with Pumlen Pat showing the highest total carbon storage (14.94 ± 5.73 Mg C/ha), followed by Lamphel Pat (5.24 ± 1.83 Mg C/ha) and Zaimeng Pat (4.06 ± 1.59 Mg C/ha). Total biomass accumulation followed similar patterns, with Pumlen Pat recording 515.99 ± 25.78 g/m2. Strong positive correlations emerged between carbon storage and water depth (r = 0.604, p < 0.001) and rainfall (r = 0.782, p < 0.001), while dissolved oxygen showed a negative correlation (r = − 0.608, p < 0.01). The calculated CO₂ equivalent storage was 476,861.90 ± 49,982.22 Mg in Pumlen Pat, 11,303.86 ± 1075.58 Mg in Lamphel Pat, and 65.86 ± 7.06 Mg in Zaimeng Pat. These findings underscore the importance of maintaining hydrological integrity and protecting larger wetland systems for optimal carbon sequestration while providing critical data for global carbon modeling efforts and informing international wetland conservation strategies.

This study investigated the effects of tank shape (circular, square, rectangular) and background color (blue, black, white) on the growth performance, immune response, and cannibalistic behavior of Ompok bimaculatus in a 12-week trial. Nine treatment combinations were tested in triplicate using a 3 x 3 factorial design. Growth parameters, immune indicators, and cannibalism rates were assessed. Results showed that circular tanks with black backgrounds yielded the best outcomes, with the highest weight gain (58.7 f 2.3 g), lowest feed conversion ratio (1.42 f 0.05), and superior immune responses, including the highest total leukocyte count (3.8 x 10 degrees f 0.2 x 10 degrees cells/mm3) and respiratory burst activity (0.58 f 0.03 OD540nm). Importantly, circular tanks with black backgrounds also exhibited the lowest incidence of cannibalism (2.3 f 0.5 %) compared to other treatments. The interaction between tank shape and color was significant for most parameters, indicating that the effect of background color varied depending on tank geometry. Analyses revealed that circular tanks provided more uniform water flow and light distribution, while black backgrounds reduced stress-related behaviors. This study highlights the importance of optimizing tank design to enhance growth, immunity, and mitigate cannibalism in O. bimaculatus aquaculture, which is crucial for improving productivity and sustainability of this endangered catfish species.

This study investigated the nutritional potential of Zanthoxylum acanthopodium seed supplementation in enhancing growth, immunity, and disease resistance of Neolissochilus hexagonolepis (chocolate mahseer) against Saprolegnia parasitica infection. Juvenile fish (10.5 ± 0.3 g) were randomly distributed into 12 tanks representing four treatment groups in triplicate: control (basal diet) and three experimental groups fed diets supplemented with 0.5%, 1% or 2% Z. acanthopodium seed powder. The experiment comprised a 60-day feeding trial with sampling conducted at Days 0, 15, 30 and 60, followed by a 14-day pathogen challenge with sampling at Says 7 and 14 post-challenge. Data were analyzed using one-way ANOVA with Tukey's post hoc test and Kaplan-Meier survival analysis. Nutritional analysis revealed Z. acanthopodium seeds contained significant bioactive compounds including alkaloids (3.45 ± 0.28 mg/g), flavonoids (2.87 ± 0.19 mg/g), and terpenoids (4.12 ± 0.31 mg/g). The 1% supplementation level demonstrated optimal effects, significantly enhancing lysozyme activity (65.2% higher, p < 0.05), respiratory burst activity (84.2% higher, p < 0.05) and serum immunoglobulin levels (72.3% higher, p < 0.05) compared to control. Growth performance showed highest weight gain (241.0 ± 9.4%, p < 0.05) and specific growth rate (2.0 ± 0.1%/day, p < 0.05) in this group. Following S. parasitica challenge, the 1% group exhibited superior disease resistance with 86.67 ± 3.3% survival compared to 58.33 ± 4.4% in control (p < 0.05), while sham-challenged fish maintained 100% survival across all treatments. Molecular analysis confirmed significantly lower fungal loads in treated groups, with 1% treatment showing minimum fungal DNA copies (1.5 × 106 copies/mg tissue) versus control (4.8 × 106 copies/mg tissue, p < 0.05). These results establish Z. acanthopodium seed's efficacy as a sustainable nutritional supplement for improving fish health and productivity while reducing synthetic antimicrobial dependency in aquaculture.

This study investigated the effects of dietary Aloe vera supplementation on stress mitigation and recovery in transported Labeo rohita fingerlings using a completely randomized design with four treatment groups (0