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Aquaculture is a rapidly expanding sector that contributes significantly to the global food supply, with Asia accounting for 90% of production and India being the second largest aquaculture fish producer. Probiotics are used in aquaculture techniques because of the need for aquatic organism development, higher disease resistance, and feed efficiency. Several potential probiotics have been shown to produce antimicrobial substances that inhibit the growth of harmful microbes and preserve intestinal microecological equilibrium by allowing them to stick to stomach surfaces, thus impairing pathogenic growth. Aquaculture has benefited various industries, pharmaceuticals, and global food security in recent decades. Nevertheless, the stress conditions that aquatic creatures experience in aquaculture cause fish to become less resilient to illness and weaken their immune systems. Therefore, impacts local people's socioeconomic conditions and economic progress in many nations. Several approaches, including conventional practices, artificial chemicals, and antibiotics, have been used to control disease in the aquaculture sector. Hence, alternative techniques are far more important to keep the microbial ecosystem in aquaculture systems healthy. This review presents the current understanding of probiotic use in aquaculture as a healthy alternative for fish and biological control agents in aquaculture and to find out its future direction for research. [ABSTRACT FROM AUTHOR]

Ghosh, S.; Anju, P.; Pattanayak, R., and Sahu, N.C., 2024. Fisheries and aquaculture in wetland ecosystems: A review of benefits, risks, and future prospects in India. Journal of Coastal Research, 40(3), 598–612. Charlotte (North Carolina), ISSN 0749-0208. Globally, wetland ecosystems are vital for supporting biodiversity and provide numerous ecosystem services, with fisheries playing a pivotal role. Wetlands are essential nurseries for fish, supporting fisheries that contribute significantly to food security and livelihoods. Wetlands offer a consistent supply of water, which can be well utilized for fisheries and aquaculture. Groundwater recharge from wetlands is crucial for irrigation, drinking water, and other uses. Additionally, wetlands control water movement, aiding in the reduction of floods and droughts. They also serve as carbon sinks and play a crucial role in mitigating climate change. However, wetlands face multiple risks, including habitat destruction due to urbanization and agricultural expansion, water pollution, overfishing, and invasive species. Climate change exacerbates these threats, altering wetland habitats and fish behavior. Sustainable wetland fisheries management is essential to mitigate these risks, emphasizing the need for community-based approaches, habitat restoration, and the development of resilient fish populations. The future prospects of wetland fisheries lie in integrated conservation strategies that balance the ecological significance of wetlands with the socioeconomic benefits to humans. Incorporating traditional ecological knowledge, scientific research, and policy interventions will be key to safeguarding these ecosystems and ensuring sustainable fisheries and aquaculture. In the context of the expanding fisheries and aquaculture industries, this study addresses the significance, risks, and future prospects of wetlands in India. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the antibiotic resistance, underlying mechanisms, antibiotic residues, and virulence genes involved in 32 multi-drug-resistant Klebsiella pneumoniae isolates from freshwater fishes in Andhra Pradesh, India. Antibiogram studies revealed that all isolates were multi-drug-resistant, harbored tetA (96.8%), tetC (59.3%), tetD (71.9%), nfsA (59.3%), nfsB (53.1%), sul2 (68.7%), qnrC (43.7%), qnrD (50%), blaSHV (75%), blaTEM (68.7%), and blaCTX-M (93.7%) genes. Multiple antibiotic resistance index was calculated as 0.54. Sixteen isolates were confirmed to be hyper-virulent and harbored magA and rmpA genes. In total, 46.9, 31.2, and 21.9% of the isolates were categorized as strong, moderate, or weak biofilm formers, respectively. All isolates possessed an active efflux pump and harbored acrA, acrB, acrAB, and tolC genes in 94% of the isolates, followed by mdtK (56.2%). Porins such as ompK35 and ompK36 were detected in 59.3 and 62.5% of the isolates, respectively. Virulence genes fimH-1, mrkD, and entB were present in 84.3, 81.2, 87.5% of the isolates, respectively. These findings imply a potential threat that multi-drug-resistant bacterial pathogens could transmit to surrounding environments and humans through contaminated water and the aquaculture food chain. [ABSTRACT FROM AUTHOR]

The Satellite Symposium on Natural Farming, held on 24th February during the 13th Indian Fisheries and Aquaculture Forum (13th IFAF) from 23 to 25 February, 2024, convened notable figures in the field, including Shri Parshottam Rupala ji, Union Cabinet Minister, Fisheries, Animal Husbandry, and Dairying (Govt. of India), and Dr. Himanshu Pathak, DG ICAR and Secretary DARE (Govt of India), and other esteemed delegates. This symposium focused on the purpose and achievements of natural farming within aquaculture, fisheries, and soil and water conservation. Natural farming was highlighted as a sustainable solution to industry challenges, surpassing conventional practices. By integrating agroecology, traditional knowledge, and modern science, natural farming minimizes environmental impact and promotes healthy aquatic ecosystems. The event featured keynote speakers and panelists who shared valuable insights, fostering a rich exchange of knowledge. The symposium emphasized natural farming's alignment with global sustainability goals by reducing reliance on synthetic inputs, lowering carbon emissions, and promoting social inclusivity. However, addressing challenges such as knowledge gaps, policy limitations, and market complexities requires collaborative efforts. As the demand for seafood rises, natural farming emerges as a promising alternative, particularly for small-scale producers and resource-constrained regions, contributing to a sustainable blue economy. Opportunities in natural farming are abundant, especially in the context of aquaculture and related sectors. Adopting natural farming practices opens doors to improved productivity, cost-efficiency, and environmental sustainability. Small-scale farmers, in particular, stand to benefit from reduced input costs and enhanced market opportunities. Additionally, natural farming fosters biodiversity and ecosystem resilience, providing long-term benefits for communities reliant on aquatic resources. The 13th IFAF underscored the importance of embracing natural farming for a resilient, equitable, and sustainable future in aquaculture and related communities. This symposium highlighted ongoing efforts to promote natural farming practices, showcasing its potential to revolutionize the industry and foster greater environmental stewardship. [ABSTRACT FROM AUTHOR]

The aim of the present study was to develop a multi‐criteria decision support system to find out possible aquaculture sites available in Nagapattinam district of Tamil Nadu, India. This study focuses on identifying possible aquaculture sites available in Nagapattinam district using remote sensing and GIS approaches. A geographical model has been developed to choose the probable aquaculture sites. The remote sensing and geographic information system techniques were applied to study the decisive parameters that play a vital role in the site suitability for aquaculture purposes. The chosen decisive parameters viz., normalized difference vegetation index, digital elevation model, soil type, normalized difference water index, land use land cover area and land surface temperature were subjected to the development of decision support system. Moreover, four different multi‐criteria decision support techniques viz., weighted overlay, analytical hierarchy process, fuzzy classified analytical hierarchy process and fuzzy classified weighted overlay were applied in the present study. The results obtained from the study rendered that the weighted overlay and the analytical hierarchy process outperforms the fuzzy classified models. The suitability ratio of analytical hierarchy process and weighted overlay methods were found to be 12.7 and 12.4 respectively. A total of 25 locations were selected and mapped in the Nagapattinam region and their accuracy was checked. The analytical hierarchy process results were obtained with an accuracy of 84%. Hence, the analytical hierarchy process provided better results than the weighted overlay technique. The study rendered that the area of 7.22% is highly suitable for aquaculture. These findings are essential for the development of sustainable aquaculture, assisting stakeholders in selecting suitable aquaculture sites that maximize productivity while minimizing environmental degradation. [ABSTRACT FROM AUTHOR]

Utilization of fruit peel wastes to grow thraustochytrids for nutritional enrichment of wastes will lower environmental and economic costs associated with feedstock specific for aquaculture industries. In this study, high-carbohydrate content agricultural wastes, such as orange, pineapple, banana, and mausambi fruit peels were enriched with essential fatty acids producing thraustochytrids Aurantiochytrium sp. ATCC276. Characterizations of fruit peels revealed the presence of high carbohydrate content (9–16%) and reducing sugars essential for the growth of thraustochytrids. Optimization for lipid production of Aurantiochytrium sp. ATCC276 was carried out using response surface methodology (RSM) in combination with different concentrations of fruit peels in solid-state fermentation (SSF) conditions. Fruit peels composed of SSF experiments were designed using a central composite design. Aurantiochytrium sp. ATCC276 cells efficiently utilized the sugar components of fruit peels for their growth and lipid accumulation. Different SSF composites made of fruit peels were significantly enriched with fatty acids of Aurantiochytrium sp. ATCC276 cells. Culturing Aurantiochytrium sp. ATCC276 cells with these waste materials demonstrated distinct responses towards lipid accumulation at different compositions. The optimized SSF composite consists of 9.91 g 100 mL−1 orange, 5 g 100 mL−1 mausambi, 4.12 g 100 mL−1 pineapple, and 8.01 g 100 mL−1 banana peels and was enriched with 8.37% of Aurantiochytrium sp. ATCC276-derived lipids. This study expands the benefits and bioprocessing potential of essential fatty acids producing Aurantiochytrium sp. ATCC276 along with fruit peel wastes which a frontier in circular bioeconomy and valorizing waste for usage. [ABSTRACT FROM AUTHOR]

The blue economy, encompassing sustainable utilization of coastal and oceanic resources, has gained global significance in the context of the developing discourse on economic growth and environmental conservation in ocean-based economies. This article delves into the multifaceted realm of India's fisheries and coastal aquaculture sectors, exploring their status, challenges and prospects through the lens of the 'blue growth' narrative. Various enabling factors, such as technological advancements, governance improvements, market and policy incentives, and investment strategies are discussed that can catalyse a smooth transition of India's marine capture fisheries and aquaculture to align with the blue developmental agenda. [ABSTRACT FROM AUTHOR]

Penaeid shrimp are economically important marine crustaceans that include species such as the black tiger shrimp, whiteleg shrimp, Atlantic white shrimp, and Indian white shrimp. Shrimp aquaculture has become a significant contributor to the fisheries industry, particularly in Asia where India is the world's second-largest producer of whiteleg shrimp. However, disease outbreaks and breeding problems remain major obstacles to the sustainable growth of shrimp aquaculture, resulting in decreased revenues and inefficient output for shrimp farmers. Recent studies have shown that the gut microbiome plays a crucial role in shrimp development and health. Next-generation sequencing technologies have contributed significantly to the metagenomic resources of crustaceans, enabling functional investigation of the gut microbiome and providing insights into the precise role of this bacterial ecosystem in shrimp diseases and development. This review summarizes the microbial diversity in the gastrointestinal tract of penaeid shrimps and how they impact the health and development of the organism. [ABSTRACT FROM AUTHOR]

The emergence of microorganisms with resistance toward antibiotics has been widely recognized as a growing hazard to public health. Here, we report the whole genome sequence of Klebsiella pneumoniae strain THK, which was isolated from an aquaculture farm in Kerala, India. Standard disc diffusion and strip methods were used for antibiotic susceptibility testing and minimum inhibitory concentration detection. The isolate showed high level of resistance against beta-lactam, aminoglycosides, fluoroquinolones, macrolides, tetracyclines, chloramphenicol, sulfonamides, and cephalosporin class of antibiotics, but were sensitive to carbapenem and polymyxins. The whole genome sequence analysis revealed that the final assembly of THK strain consisted of 30 contigs of 5, 199,186 bp including four plasmid sequences plasmid_690 (1 contig), plasmid_710 (9 contigs), plasmid_1222 (6 contigs), and plasmid_1528 (1 contig). Sequence analysis revealed that the isolate has a number of genes encoding for antibiotic resistance and virulence. The findings indicated that antibiotics present in aquatic environments at sub-inhibitory concentrations increase the selection pressure affecting the cell function of even normal aquatic microorganisms to change the genetic expression of virulence factors or acquire resistance genes through various transfer mechanisms. This strain would be of significant interest for thorough comparative genomic study, given the known vast diversity of pathogenic and antibiotic resistance potentials. [ABSTRACT FROM AUTHOR]

The paper uses illustrations from rural India and Bangladesh to develop a critical analysis of practices and experiences of poverty often overlooked in development policies. It challenges the principle measurement, calculative rationality and static representation in anti-poverty interventions that present poverty as a 'problem' to be resolved. It draws on poststructuralist ideas to express poverty differently and shift from problem-solving to problematisation. Drawing on the concept of 'rhizome' it highlights the connectivity, heterogeneity and multiplicity of poverty. Examples from interviews and photo diaries illustrate manifold poverty as a combination of heterogeneous activities, objects and affects that complicate development ethics and challenge the logic of reason in existing policies. The paper explores improvisation, experimentation, hope and repetition as mechanisms for critically evaluating aquaculture-led development and attending to overlooked objects, uncertain outcomes and untold stories of disadvantage. [ABSTRACT FROM AUTHOR]

Aeromonas hydrophila, a natural inhabitant of aquatic environments is known to become pathogenic in fish under favourable conditions. It has also been reported to cause infections in humans and animals. The prevalence, virulence-associated genes, and antimicrobial resistance of 57 A. hydrophila isolates from freshwater fish farms in Andhra Pradesh, India, were studied. The isolates showed resistance to trimethoprim (35.9%), co-trimoxazole (21.1%), oxytetracycline (19.3%), doxycycline (17.5%), and enrofloxacin (8.93%), but were completely sensitive to ciprofloxacin. The majority of the A. hydrophila isolates were strong (33%), moderate (50%), and weak (17%) biofilm formers, playing roles in virulence and colonization in hosts. The virulence gene distribution in representative A. hydrophila isolates was very high for enolase (enol, 96.4%), followed by flagellin (fla, 94.7%), cytotonic enterotoxins (alt, 91.2%), cytotoxic enterotoxins (act, 84.2%), lipase (lip, 77.1%), serine protease (ahp, 54.3%), aerolysin (aerA, 50.8%), and elastase (ahyB, 43.8%), respectively. 80% of the isolates carried a maximum of four virulence genes, whereas none carried the DNAase (exu) or haemolysin (hly) genes. Hemolytic assays on blood agar demonstrated that 70% of the isolates were β-haemolytic. The findings of the study will help to create awareness among aquaculturists of the potential risk of the spread of isolates and the virulence-associated genes across other sectors and the need to adopt best management practices in aquaculture. [ABSTRACT FROM AUTHOR]

Since the natural resources have been over-utilized, aquaculture has emerged as the food industry with the highest rate of growth worldwide and established itself as a source of high-quality protein. India is second in the world in terms of fish resource culture. The Indian economy depends heavily on the fishing industry for possibilities on how the rural and poor might make a living. Omnipotent bacteria are present in water as microflora and may play a significant role in harming the fish farming sector. The future growth of aquaculture depends on early illness detection and the development of effective vaccinations. From water samples taken in the Meja Regions of Uttar Pradesh, the current research sought to isolate and maybe identify bacteria with the potential for growth. Materials and Techniques 20 different ponds’ worth of water samples. The samples that were gathered were located and examined. Using the agar plate technique, the bacterial load in the samples was assessed for the potential indicator species. According to a preliminary investigation, the majority of the water samples included potential Vibrio cholerae, E. coli, S. thyphimurium. In the chosen fishponds, other bacteria such as Staphylococcus, Micrococcus and E. coli were also found. It was discovered that the ponds were severely polluted with harmful microorganisms, particularly bacteria that pose a significant danger to fish kept in captivity. [ABSTRACT FROM AUTHOR]

Soil salinization is a widespread phenomenon leading to land degradation, particularly in regions with brackish inland aquaculture ponds. However, because of the high geographical and temporal fluctuation, monitoring vast areas provides substantial challenges. This study uses remote sensing data and machine learning techniques to predict soil salinity. Four linear models, namely linear regression, least absolute shrinkage and selection operator (LASSO), ridge, and elastic net regression, and three boosting algorithms, namely XGB regressor, LightGBM, and CatBoost regressor, were used to predict soil salinity. Cross-validation was performed by splitting the data into 30% for model testing and 70% for model training. Multiple metrics such as determination coefficient (R2), root mean square error (RMSE), mean square error (MSE), and mean absolute error (MAE) were used to compare the performances of these algorithms. By comparison, the CatBoost regressor model performed better than the other models in both testing (MAE = 0.42, MSE = 0.28, RMSE = 0.53, R2 = 0.92) and training (MAE = 0.49, MSE = 0.36, RMSE = 0.60, R2 = 0.90) phases. Hence, the CatBoost regressor model was recommended for monitoring soil salinity in India's massive inland aquaculture zone. [ABSTRACT FROM AUTHOR]

Coastal aquaculture is an important economic activity in India dominated majorly by shrimp culture, which involves a range of interconnected processes that are challenging to analyse and optimise without a systematic approach. System dynamics modelling is a useful tool for understanding and predicting the behavior of complex coastal aquaculture systems. here, we review the status of dynamic simulation modelling works undertaken in aquaculture, which can provide directives for various researchers working on developing simulation models for shrimp aquaculture. There is a need to assess the impact of dynamic forces on the animals during the culture period which could be addressed through these models. System dynamic models assist decision-makers to augment potential measures for aquaculture-related problems under different possible scenarios. System dynamic models developed in aquaculture were related to feeding, water quality parameters, nitrogen dynamics, growth, etc. The strengths and limitations of software packages used in developing the simulation models are discussed. Considering the economic potential of shrimp aquaculture, it is important to develop an integrated dynamic model for predicting all the sub-processes of shrimp aquaculture. [ABSTRACT FROM AUTHOR]

Fish, crab, prawns and other seafood are among the animal-derived foods that are regarded as the safest in contemporary world in terms of enhancing food security. Globally, aquaculture is growing rapidly. India has a big impact on aquaculture due to its proximity to water. In the dynamic context of aquaculture ponds, the interactions between water quality factors are complicated. For instance, unbalanced temperature and pH conditions may make ammonia more dangerous. In poor quality water, fish do eat, but the calories are changed to promote health rather than development. When the water is of high quality, animals can defend themselves most effectively. In this paper, the proposed model monitors and controls fish growth, detection of aquatic animal illnesses and Water Quality Index (WQI). Automated aquaculture employing Arduino and image enhancement techniques are used mainly to spot fish infections. Additionally, management of aqua system is employed to generate high-quality aqua food for customers. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of controlling turbidity, dissolved oxygen, ammonium‐ion concentration, and water‐temperature to maintain the desired water quality in an intensive aquaculture plant. The research is carried out to fit into the present scenario of intensive aquaculture in India. The plant model along with uncertain parameters are derived using physical laws and the data acquired from an aquaculture pond in Assam, India. A pre‐compensated multi‐variable quantitative feedback theory (QFT)‐based fully populated robust matrix controller is proposed to mitigate the control challenge. A novel method is used to design the pre‐compensator to enhance the diagonal dominance of plant transfer function matrix. The desired robust stability, reference tracking, and sensitivity specifications are fulfilled by the proposed QFT‐based robust controller despite the parametric uncertainty. The effectiveness of the proposed method is validated through numerical simulation. A comparative study against a H∞$$ {H}_{\infty } $$ controller shows that the proposed controller strategy gives a satisfactory performance compared to it. [ABSTRACT FROM AUTHOR]

Circular bio‐economy of biogenic resources designates the plunging use of such resources, adopting a systemically formatted pathway towards sustainable economic development. Aquaculture has been perceived to play a pivotal role in supplying protein and mineral rich organic food to a growing human population. The exponential growth of aquaculture sector during the last four decades has established itself in a fundamental way to supply the global need of valuable animal protein. However, the on‐going production strategies may likely be proved unsustainable if the present level of exploitation and resource use continues. Emphasis only on augmenting productivity and yield with insufficient and/or inefficient pollution control measures, and water quality clean‐ups, direct discharge of effluents in the open ambient environment from aquaculture production systems have manifested in variable degrees of pollution particularly in the open water bodies; thereby causing significant impairment of these ecosystems. The paper discusses the various techniques of bioprocessing in re‐circulatory aquaculture system, aquaponics, biofloc technology, waste water aquaculture and circular enclosure culture for inland water bodies to recycle the waste generated from fisheries and aquaculture and converting the same to fish flesh, at the same time reducing the impact on environment. The study also highlights the potential attributes and benefits of circular bio‐economy, discusses recent advances and updates the current status of knowledge base for future research planning towards sustainability. Rationality perspectives of the system design with regards to simplicity, energy efficiency and budget in attaining circularity emerged as pertinent factors in bio‐circularity in resource use in aquaculture. [ABSTRACT FROM AUTHOR]

Aquatic environment can act as reservoir and disseminator of antimicrobial resistance and resistant pathogens. Novel high-risk carbapenem resistant E. coli (CREC) are continuously emerging worldwide; however, the occurrence of CREC in freshwater aquaculture environment is largely unexplored. To fill this gap, large scale sampling of freshwater pond sites and retail fish markets was done between Oct 2020 and Oct 2021 to investigate the CREC contamination in fish. The frequency of CREC contamination in the freshwater fish was 6.99% (95% CI: 3.78–10.20%). All the isolates were MDR and harbored carbapenemase encoding gene, blaNDM-5 along with other antimicrobial resistance genes (ARGs), blaTEM (64.7%), blaCTX-M-15 (35.3%), blaOXA-1 (5.9%), tet(A) (100%), sul1 (94.1%), qnrS (82.3%), cat1 (35.3%), and cat2 (23.5%). The isolates belonged to phylogroup C and showed low virulence gene profile. ERIC-PCR grouped the isolates into five clusters (I-V). The isolates of clusters I, II, and III were identified as ST167 (76.4%) and of cluster IV as ST361 (17.6%). This is the first report documenting the contamination of NDM-5 producing E. coli ST167 and ST361 of clinical/livestock lineage in freshwater fish from India. The blaNDM-5 was significantly associated with ARGs, tet(A), and sul1; and plasmid replicons, IncF, IncI1, and IncP, signifying the presence of blaNDM-5 and associated ARGs on these transferable plasmids. These findings were validated by the successful conjugal transfer of blaNDM-5 and associated ARGs into non-CREC strain (J53). Our study highlights the ability of CREC to disseminate antimicrobial resistance which has health implications and environmental concerns. [ABSTRACT FROM AUTHOR]

Infectious disease happens to be one of the major constraints in aquaculture and responsible for huge losses to livelihoods worldwide. In the present study, a gram-negative bacterium responsible for mortality in Cirrhinus mrigala cultured in a farm located in Kamrup (rural) district, Assam, India, with previous records of mortality was identified. This bacterium was isolated and identified as Aeromonas veronii based on colony morphology, biochemical characteristics and 16S rRNA and rpo B gene sequencing. The naturally infected fish showed signs of skin lesions and red spots on body surface, and associated with mortality. Its virulence potential was confirmed by experimental challenge and analysis of Aeromonas specific virulence factors like aerolysin, hemolysin and enterotoxin. Experimental challenge with concentration of 106 and 107 CFU bacterial suspension resulted in 73.33 and 86.67% mortality rate, respectively in healthy C. mrigala fish within 120 h post injection. Histopathological analysis revealed gross pathological changes including liver, kidneys and gills. The isolate was found to be sensitive to multiple antibiotics but resistant to ampicillin, penicillin and erythromycin. This study might be the first report of Aeromonas veronii infection in the Indian major carp, C. mrigala. [ABSTRACT FROM AUTHOR]

Tilapia is a widely cultured species native to Africa; these fish are prolific breeders and constitute an economically important fish species supplying higher-quality protein. To meet the global food demand and achieve the UN's Sustainable Developmental Goals (SDG), the aquaculture industry has conceived of productive solutions with the potential for adaptability, palatability, and profitability. Tilapia may play a vital role with respect to the possibility for sustainability in the nutrition and aquaculture sectors. India contributes to the promotion of aquacultural practices through a structural framework focused on agricultural, environmental, geographical, and socio-economic factors that provide opportunities for tilapia farming. Globally, the Indian aquaculture sector is currently the second largest in terms of aquacultural production but is moving toward different species that meet SDG and facilitate international marketing opportunities. The farming of aquacultural species with innovative technology constitutes an efficient use of resources. Productive research on feeding, disease management, construction, and layout helps overcome the challenges faced in aquaculture. These focused and sustained factors of the aquaculture industry offer a latent contribution to global food security. This review reports on the state of the art, the challenges regarding tilapia aquaculture in India, and the Indian government's schemes, missions, subsidies, projects and funding related to tilapia production. [ABSTRACT FROM AUTHOR]

Aims This study investigated the tetracycline resistance potential of heterotrophic bacteria isolated from twenty-four freshwater fin-fish culture ponds in Andhra Pradesh, India. Methods and results A total of 261 tetracycline resistant bacteria (tetR) were recovered from pond water, pond sediment, fish gills, fish intestine, and fish feed. Bacteria with high tetracycline resistance (tetHR) (n  = 30) that were resistant to tetracycline concentrations above 128  μg mL−1 were predominantly Lactococcus garvieae followed by Enterobacter spp. Lactococcus lactis, Enterobacter hormaechei, Staphylococcus arlettae, Streptococcus lutetiensis, Staphylococcus spp. Brevundimonas faecalis, Exiguobacterium profundum, Lysinibacillus spp. Stutzerimonas stutzeri, Enterobacter cloacae , and Lactococcus taiwanensis. Resistance to 1024 μg mL−1 of tetracycline was observed in L. garvieae, S. arlettae, Enterobacter spp. B. faecalis. Tet(A) (67%) was the predominant resistance gene in tetHR followed by tet(L), tet(S), tet(K) , and tet(M). At similar concentrations of exposure, tetracycline procured at the farm level (69.5% potency) exhibited lower inhibition against tetHR bacteria compared to pure tetracycline (99% potency). The tetHR bacteria showed higher cross-resistance to furazolidone (100%) followed by co-trimoxazole (47.5%) and enrofloxacin (11%). Conclusions The maximum threshold of tetracycline resistance at 1024 μg mL−1 was observed in S. arlettae, Enterobacter spp. B. faecalis , and L. garvieae and tet(A) was the major determinant found in this study. [ABSTRACT FROM AUTHOR]

Marine products have remained a consistent and leading foreign exchange earner to India for a long time. This study analyses the status and trend in marine products export from India and sketches the way ahead. Augmenting exports without hampering domestic nutritional security calls for enhancing domestic fish production through science-based culture practices, promoting value addition, improving quality assurance systems and effecting enabling policy changes. [ABSTRACT FROM AUTHOR]

This paper examines the drivers and impacts of degradation of agricultural land in a village in a South Indian coastal delta. Drawing on insights from political economy and political ecology scholarship, it argues that there is a dialectical relation between land degradation and social inequalities, i.e. the biophysical degeneration of land is not only caused by human and environmental factors but it also generates social contradictions which further intensify both land degradation and social inequalities. The paper demonstrates, firstly, that coastal land degradation has been generated in the form of soil salinity through a confluence of the inherent environmental vulnerabilities of the region, forces of commoditization (especially those associated with shrimp aquaculture), existing social hierarchies and state policy. Secondly, it shows that social groups differentiated by caste, class and gender have experienced these changes differently. A small, relatively well-off section of the locally dominant caste landowners has benefitted from shifting from paddy to shrimp aquaculture, which is leading to a further increase in salinisation. Others have to bear the brunt of decreasing productivity of land for crop cultivation, leading them to abandon or reduce cultivation and increase dependence on non-agricultural sources of income, especially through male outmigration. Women's burden of work has increased while their capacity to earn wage-income has declined. Without any concerted state effort to either restore the land or to alleviate the widespread agrarian distress, land degradation has developed into a continuously evolving downward spiral, but one where there will still be some winners and many losers. [ABSTRACT FROM AUTHOR]

The butter catfish, Ompok bimaculatus, belonging to the silurid family, is widely regarded as an important food fish for aquaculture diversification in India. Furthermore, the species poses a threat due to habitat degradation and other anthropogenic factors, and has been categorised as "near threatened", therefore, its culture promotion is warranted. To establish a successful breeding programme, a precise understanding of the life history, and biology (reproductive/feeding) of the fish will assist hatchery managers and researchers. Studies in these areas have been undertaken by several groups over the years, but without much coherence, the data are still fragmented. Few attempts on the culture attributes of this catfish have been performed under both mono- and polyculture systems to bring about parallel promotion through aquaculture in a larger part of the subcontinent. Highlighting this, we have tried to analyse and present a consolidated account of the morphological characteristics, feeding habits, reproductive biology, early developmental ontogeny, and culture potentials of O. bimaculatus in India. This review was also prompted by the paucity of information on the cultural aspects of the species. Additionally, based on the reported studies, future directions and perspectives of the culture promotion of the species are proffered to ensure future research initiatives. [ABSTRACT FROM AUTHOR]

The aquaculture expansion has made significant contributions to global food security, socio-economic development and, if implemented sustainably, can help preserve stable coastal environments. This study explicitly details the rapid expansion of largescale aquaculture growth across the Kolleru and Upputeru regions of South India. We developed a novel classification method for automated extraction of aquaculture ponds in the Kolleru zone using the Canny Edge-Otsu algorithm to segment and extract the ponds applied to SAR-VV images in Google Earth Engine. This approach enables the area estimation of dense aquaculture ponds are essential for monitoring and management purposes. The results indicated that this method could effectively map the aquaculture ponds and the overall accuracy achieved in 2020 for the Kolleru and Upputeru areas by 90.6% and 95.7%, respectively. The aquaculture maps of this study can help government organizations, resource managers, stakeholders, and decision-makers understand the dynamics and plan sustainable measures in this area. [ABSTRACT FROM AUTHOR]

The present study depicts the disease incidences in the aqua farms of Moyna, West Bengal, India, during 2018-2020 and aqua-drugs used by farmers to combat diseases. A total of 132 fish disease incidences were reported, among which parasitic diseases were the most common (53.03%) followed by bacterial diseases (27.27%), diseases due to poor nutrition and environmental fluctuations (10.61%), and fungal diseases (9.09%), respectively. Out of the 53.03% parasitic disease incidences reported, Argulus (22.86%), Dactylogyrus (17.14%), Gyrodactylus (10.00%), Myxospores (10.00%), Lernaea (8.57%), Ichthyophthirius (5.71%) and Trichodina (4.29%) were the major disease-causing parasites. Among bacteria, Pseudomonas spp. and Aeromonas spp. were the most dominant genera encountered in diseased fish. Labeo catla was the most susceptible fish species followed by Labeo rohita, and Cirrhinus mrigala. Seasonal influence in disease occurrence was noticed. Monsoon and winter were favorable seasons for disease outbreaks. The influence of water quality parameters like hardness, pH, ammonia, total dissolved solids of water, and total organic carbon of sediment had a significant correlation with parasite abundance. Farmers of Moyna were observed to use a wide range of chemicals and aqua-drugs to control diseases and related problems. The majority of the fish farms of Moyna were found using feed additives and supplements (32.00%) followed by sanitizers and disinfectants (24.00%), probiotics (17.00%), anti-parasitic drugs (11.00%), antibiotics (8.00%), and other chemicals (20.00%). Lime (calcium carbonate) and zeolite along with sodium chloride, potassium permanganate, formalin, and calcium hypochlorite were extensively used as disinfectants in Moyna. Farmers being unaware of the adverse consequences of using chemicals and aqua-medicines are fully dependent on private aquaculture consultants for time-to-time advice, which may have augmented their indiscriminate use. Initiative for implementation of better management practices by creating awareness among farmers and adopting strict aquaculture policy guidelines might improve the scenario. [ABSTRACT FROM AUTHOR]

Viral diseases arising in farmed fish are an ongoing challenge to the aquaculture industry, causing severe mortality and economic losses. Recently, there has been a spike in the incidence of a viral disease caused by Tilapia Parvovirus (TiPV) inflicts irreparable damage, and large-scale fish kills in the farmed tilapia species. We investigated a case of disease outbreak and severe mortality in cage and wetland farms of tilapia in West Bengal and Odisha, India. The symptomatic fish showed clinical signs, including hemorrhage, discoloration, ulcer, and redness in the body surfaces. Further analysis revealed that Tilapia Parvovirus was associated (validated by PCR, phylogenetic analysis, and cell line assay) with the infection and mortality of tilapia. The virus was detected in gill, heart, spleen, liver, and kidney samples collected from apparently healthy (asymptomatic) and symptomatic tilapia samples from cage and wetland farms. At the same time, negative results were found in the brain and skin tissue samples. The histological analysis revealed that TiPV induces severe damage invariably in almost all studied tissue, including the liver, kidney, spleen, gill, heart, and brain of tilapia samples. The viral quantification analysis showed that the viral genome was higher in the liver, spleen, and heart than in the tilapia samples' gill, kidney, or brain tissue. Furthermore, the study indicated that TiPV infection has a significant effect on the health of tilapia. The tilapia exhibited an immune reactivity toward TiPV infection (upregulation of chemokine receptors, CRs and interleukin 1β, IL-1β), the majority of the studied immune genes (interleukin 8, IL-8; Toll-like receptors 7, TLR7; tumour necrosis factor α, TNF-α; major histocompatibility complex II, MHC II and nuclear factor kappa B, NF-kB) were significantly downregulated in the kidney, spleen and liver tissue samples of symptomatic tilapia. Further, the in vivo challenge assay confirms that the isolated TiPV is a novel parvovirus pathogen that causes massive mortality in tilapia. The lessons learned from the first cellular and molecular description associated with TiPV epidemiology from wetland and cage farms of tilapia could be critical to developing the current state of the tilapia farming industry. Additionally, a holistic approach is needed to develop management measures to control the virulence and risk factors of TiPV., Competing Interests: Competing interests The authors declare no competing interests. Institutional review board statement All experiments were performed according to the approved animal utilization protocol approved by the Institutional Animal Ethics Committee, ICAR-CIFRI, Kolkata, India for the experimental setup. All procedures were made with maximal efforts to minimize fish suffering., (© 2024. The Author(s).)

The increasing trend of antimicrobial resistance (AMR) pathogens in aquaculture makes it is imperative to find control measures for AMR pathogens causing high economic losses in aquaculture. In the present study, a multidrug resistance (MDR) Aeromonas hydrophila bacterium was isolated from kidney samples of diseased carp originating from a fish farm in Awankot, Rupnagar, Punjab, India. Moribund-infected fish exhibited large irregular hemorrhages on the external body surfaces, exophthalmia and fin-rot-like lesions. Phenotypic characterization using Rimler-Shotts (RS) media showed characteristic yellow color colonies and beta hemolysis on sheep blood agar. Genotyping using species-specific primers for the rpoB and gyrB genes characterized the isolate as A. hydrophila. The Multiple Antibiotic Resistance (MAR) index analysis showed that the isolated A. hydrophila had an MAR score of 0.29 signifying its resistance to more than three antibiotics, which underscores the need of finding treatment methods for MDR A. hydrophila isolates causing disease in aquaculture. Bacteriophages are considered a better eco-friendly alternative to antibiotics because of their inherent properties of not causing drug residues and resistance. Of the 13 phages tested, the Aeromonas veronii phage designated as AVP3, initially isolated against Aeromonas veronii, showed lytic activity against the MDR A. hydrophila isolated from diseased carp in this study. In addition, it also showed the lytic activity against Aeromonas spp. And A. caviae indicating that it had lytic properties against a wide host range within the Aeromonas species. This finding points to the potential efficacy of bacteriophages in mitigating pathogenic infections in aquaculture., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Understanding the efficacy of antimicrobials against pathogens from clinical samples is critical for their responsible use. The manuscript presents in vitro efficacy and antimicrobial resistance (AMR) genes in seven species of fish pathogens from the disease outbreaks of Indian aquaculture against oxytetracycline, florfenicol, oxolinic acid, and enrofloxacin. In vitro efficacy was evaluated by minimum inhibitory concentration and minimum bactericidal concentration. The gene-specific PCR screened AMR genes against quinolones (qnrA, qnrB, and qnrS) and tetracyclines (tetM, tetS, tetA, tetC, tetB, tetD, tetE, tetH, tetJ, tetG, and tetY). The results showed that Aeromonas veronii (45%) showed the maximum resistance phenotype, followed by Streptococcus agalactiae (40%), Photobacterium damselae (15%), Vibrio parahaemolyticus (10%), and Vibrio vulnificus (5%). There was no resistance among Vibrio harveyi and Vibrio alginolyticus against the tested antimicrobials. The positive association between tetA, tetB, tetC, tetM, or a combination of these genes to oxytetracycline resistance and qnrS to quinolone resistance indicated their potential in surveillance studies. The prevalence of resistance phenotypes (16.43%) and evaluated AMR genes (2.65%) against aquaculture antimicrobials was low. The resistance phenotype pattern abundance was 0.143. All the isolates showed susceptibility to florfenicol. The results help with the appropriate drug selection against each species in aquaculture practices., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Objective: Despite generating huge employment opportunities and profitable business, fishing is considered a dangerous occupation due to challenging weather conditions and exposure to unhealthy occupational factors and lifestyles, which contribute to various health issues. However, few studies have examined the health status of shrimp cultivators. Consequently, this study aims to estimate the age group-wise burden of non-communicable diseases (NCDs) among shrimp cultivators., Methods: Simple random sampling was employed for collecting data. The sample size was 357 shrimp cultivators. Disability-adjusted life years (DALY) and relative risk (RR) methods were used to measure the burden of NCDs among shrimp cultivators. This study reported the burden of NCDs per 100,000 shrimp cultivators., Results: The top five prevalence of NCDs per 100,000 shrimp cultivators were mental disorders (85,434), musculoskeletal diseases (26,325), digestive diseases (9,803), diabetes (5,882), and cardiovascular diseases (4,481). DALY per 100,000 shrimp cultivators was 33,407.59, while at the national level, it was 24,775.99 per 100,000 people across all age groups. The RR of NCDs among shrimp cultivators in terms of DALY was 1.35, indicating a 0.35 times higher burden of NCDs among shrimp cultivators than at the national level. The largest RR of NCDs was found among shrimp cultivators aged 15-49 years (1.85), followed by 50-69 years (1.09). The highest percentage changes in the burden of NCDs among shrimp cultivators, resulting from changes in the methods of estimating DALY, was observed in the age group of 70 years and above (-48.36%) followed by 15-49 years (-46.08%) and 50-69 years (-40.33%) when compared to the baseline method of estimating DALY without utilizing age weightage and discount rate., Conclusions: Focus should be given to improving the lifestyle and occupational factors of shrimp cultivators to mitigate the burden of NCDs.

Co-infection of Lactococcus garvieae and Aeromonas hydrophila, has been confirmed from diseased Nile Tilapia (Oreochromis niloticus), Chithralada strain cultured in a freshwater rearing pond of Alappuzha district of Kerala, India. The aetiological agents behind the disease outbreak were bacteriologically proven and confirmed by 16SrRNA sequencing and phylogenetic analysis. PCR detection of the virulent genes, showed existence of adhesin and hemolysin in L. garvieae and aerolysin in A. hydrophila strain obtained. To fulfil Koch's postulates, challenge experiments were conducted and median lethal dose (LD 50 ) of L. garvieae and A. hydrophila was calculated as 1 × 10 5.91 CFU per mL and 1 × 10 5.2 CFU per mL respectively. Histopathologically, eyes, spleen, and kidney were the predominantly infected organs by L. garvieae and A. hydrophila. Out of the 13 antibiotics tested to check antibiotic susceptibility, L. garvieae showed resistance to almost 7 antibiotics tested, with a resistance to Ciprofloxacin while A. hydrophila was found resistant to Streptomycin and Erythromycin. Understanding the complex interaction between Gram-positive and Gram-negative bacteria in the disease process and pathogenesis in fish host will contribute to efficient treatment strategies. As a preliminary investigation into this complex interaction, the present study is aimed at phenotypic and genotypic characterization, pathogenicity evaluation, and antibiotic susceptibility of the co-infecting pathogens in a diseased sample of freshwater-farmed Nile tilapia., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

The paper adopts the conventional data envelopment analysis (DEA) and bootstrap procedure to analyze the technical efficiency, while tobit regression is applied to identify the factors affecting efficiencies of exotic fish polyculture in Jammu and Kashmir (India). According to the statistical analysis of the variables utilized, there was a lot of variability in the inputs being used by the farmers, with the most variation being in the lime input. The DEA estimated technical efficiency for the sample farms in Jammu and Kashmir is 0.9771 and 0.9741, respectively, with least technical inefficiency of 3%. The bias-corrected (bootstrapped) technical efficiencies found were slightly lower than the ones estimated by conventional DEA. Mean allocative and cost efficiencies for sample farms in the Jammu region were 92% and 75%, respectively, and 84% and 74%, respectively, for farmers in the Kashmir region. Farming experience, age, and education have favorable impacts on technical efficiency of farmers in the state, but family size showed negative impacts. Efficiency improvement will eventually lead to increase in the production providing better scope for marketed surplus. More fisheries extension is suggested for expanding the exotic fish culture in the state making the enterprise a more profitable venture. [ABSTRACT FROM AUTHOR]

The Sundarbans, major marshy land, and brackish water ecosystem of the West Bengal were inhabited by many species of fishes which were the main dependants of the people living there. The present investigation was conducted using a questionnaire survey, participatory rural appraisal, key informant interviews, and focus group discussion and to assess the present state of production of major cultivable species of Sundarbans like mullet, shrimp, tilapia, mud-crabs, giant prawn and Asian seabass. A socioeconomic and technical survey of 45 trained and 45 traditional practitioners of aquaculture were conducted from May 2017 – April 2018. This study and appraisal intended to compare the socioeconomic relationship between traditional fish farmers and trained aquaculturists in Indian Sundarbans. The modern farmers usually practice the farming systems like Jayantirohu cultivation, white shrimp cultivation, genetically improved farmed tilapia, crabs fattening and crab culture; periphyton based giant prawn cultivation and Asian seabass culture with forage feeding with bait fishes. The trained farmers were enriched with much knowledge and information gained from various training, which the traditional farmers were lacking. It was found average benefit-cost ratio for traditional farming and modern farming system of 1:1.89 for traditional fish farmers and 1:3.13 for trained farmers. It was helping the modern practitioners to earn more profit to suffice their family needs as well as they were now accomplishing more safety, security measures for their family, investing more in their aquaculture practices. The yield of fish culture was affected by pond conditions, family labor engagement, and resource endowment of the fisher family. Linkage with formal financial institutions, subsidized input support from the fishery department, and investment in human resource development of farmers might be some point of intervention to boost fish culture in the coastal zone of West Bengal, India. [ABSTRACT FROM AUTHOR]

China's hegemony in global fish production remains unquestioned. This paper tries to analyze the trend in the production of fish production in India and China giving emphasis to aquaculture fish production. In aqua production in the 2000s, India appears to have made a turnaround compared to the position of China. In the 2010s, India registered a growth rate of 78 percent almost the same as in the 2000s while China's decadal growth rate went down to a little over 50 percent. The variation difference in the growth trend of total fisheries production in India has been much more pronounced compared to that of China. The difference in variation of the growth has also been discernible in the Aquaculture production as well. While China's long-term growth has been steadier and steeper during the period under the study, India has shown relatively much-pronounced volatility, particularly in the second half of the 1990s and the first half of the 2000s. But in the later part of the 2010s, the volatility in the growth trend in respect of aqua production in India seems to have disappeared. [ABSTRACT FROM AUTHOR]

Ministry of Fisheries, Animal Husbandry and Dairying, Government of India, has recently rolled out its flagship scheme 'Pradhan Mantri Matsya Sampada Yojana (PMMSY)', aimed at ambitious expansion of the domestic seaweed sector. Consequently, it gave emphasis on diverting the focus from a monoculture of Kappaphycus alvarezii to other candidate species, Gracilaria dura—which yields high quality agar—is an ideal example. Furthermore, currently agar requirement for the country is 400 tonnes year−1 and 4,000 tonnes dry of feedstock is needed to cater to this demand. With this backdrop, commercial farming of G. dura has been initiated along the northern west coast of India. We interviewed 20 households from two coastal villages, namely, Simar and Rajpara to document their socio-demographic profiling and computing livelihood asset index. The total literacy rate of Simar was found to be 25% and Rajpara was 20%, with population of 7445 and 12,000 respectively. Demographic analysis revealed equal gender participation; a higher proportion of seaweed growers (30%) were under the age group of 21–30 years; 15% exclusively dealt with seaweed farming (while others relied on additional livelihood source); spending from earning had positive implications on various aspects, namely, household food security, improving their purchasing power to meet daily requirements (50%), education to their children (30%); followed by savings (10%) and medical and other expenditure (10%). The 'human asset index' was found to be 0.487, while the 'natural asset index' was 0.376; the 'physical asset index' was 0.69; the 'financial asset index' was 0.205; the 'social asset index' (SAI) was 0.557, while the 'total livelihood asset index' was 2.315. To the best of our knowledge, asset indicators have been first time recorded for seaweed farmers from anywhere in the word for longitudinal analysis. The data will be useful to researchers and policy-makers for household welfare dynamics studies. [ABSTRACT FROM AUTHOR]

Cobia (Rachycentron canadum) is a marine fish of high economic value that grows at a fast rate. However, intensive fish farming has led to disease outbreaks in cobia cultures, which is highly costly to the industry. The impact of infectious diseases on cobia production has led to the inappropriate and increased use of chemicals and antibiotics, which negatively affects the environment and human health and promotes the spread of drug-resistant pathogens. Hence, prophylactic measurements, such as the use of immunomodulators, are required to improve the health of cultured animals against pathogens. In this study, we examined the effects of Sarcodia suiae water extract (SSWE) in cobia in vitro and in vivo. We found that treatment with SSWE could significantly increase the expression of cytokines (e.g., IL-1β , IL-6 , IL-10 , IL-12 , and TNF-α) and chemokines (e.g., IL-8) in primary cultured head kidney leukocytes. Intraperitoneal injection of SSWE (20 μg/g body weight) promoted higher expression of IL-6 , IL-8 , IL-10 , IL-12 , chemokines (e.g., CC1), and antibodies (e.g., IgT) in head kidney and spleen tissues of the fish compared with other dose levels. Additionally, we describe for the second time (only after India) of the isolation of Photobacterium damselae subsp. damselae (Phdd) from a deadly epizootic in cage-farmed cobia. An intraperitoneal inoculation of SSWE before Phdd challenge showed that SSWE treatment could delay the onset of mortality of cobia. Finally, fish that received SSWE intraperitoneally before infection with Phdd exhibited elevated expression of Th1-type cytokines, namely, IL-8 , IL-12 , TNF-α , and IFN-γ. At the same time, the expression of Th2-related factors (such as IL-10 in the head kidney, and IgM and IgT in the spleen) were lower for the fish that received SSWE instead of PBS before the Phdd challenge. The results indicate that SSWE treatment facilitates the induction of Th1-type cytokines in cobia to fight against Phdd infection and has the potential to be used as an immunostimulant and vaccine adjuvant for fish. [ABSTRACT FROM AUTHOR]

In shrimp farming, disease is a serious concern that affects production globally. Enterocytozoon hepatopenaei (EHP) was rarely found till 2009 in the black tiger shrimp Penaeus monodon. But EHP infection became more widespread during mid-2010 in Asia and affected the most common cultured shrimp species Penaeus vannamei. Enterocytozoon hepatopenaei (EHP) affects the hepatopancreas of the shrimp and causes Hepatopancreatic Microsporidiosis (HPM). HPM is a disease that delayed host growth and development. HPM is more difficult to manage than other infectious disease due to a lack of sufficient knowledge about its reservoirs and mode of transmission. This study summarized the life cycle of EHP spore and the molecular approaches used by them as an obligate intracellular parasite. It also analyzes existing and novel approaches for the diagnosis, as the majority of the present work on EHP concentrates on that area. We outline the current understanding of EHP infection and transmission dynamics, as well as currently recommended, feasible control strategies being used to restrict its harmful influence on shrimp farming. We also highlight the critical knowledge gaps that must be addressed immediately. [ABSTRACT FROM AUTHOR]

Healthy oceans and seas are essential to our existence. They cover 70 percent of our planet and we rely on them for food, energy and water. Yet, we have managed to do tremendous damage to these precious resources. We must protect them by eliminating pollution and overfishing and immediately start to responsibly manage and protect all marine life around the world. Everyone is responsible for to make sure that we meet the Global Goals. Following 10 targets to create action to conserve and sustainably use the oceans, such as (1) Reduce Marin Pollution, (2) Protect & Restore Ecosystem, (3) Reduce ocean Acidification, (4) Sustainable Fishing, (5) Conserve coastal & Marin areas, (6) End subsidies contributing to overfishing, (7) Increase the Economic benefits from sustainable use of Marin Resources, (8) Increase scientific knowledge, Research & Technology for Ocean Health, ((9) Support Small Scale Fisheries, (10) Implement & Enforce International Sea Law. SDG, is commonly popular as Global Goals, build on the success of the Millennium Development Goals (MDGs) and aim to go further to end all forms of poverty. India is fully committed to follow. India has made steady progress towards achieving the United Nations' Sustainable Development Goals (SDGs) in areas of health, energy, and infrastructure, as per NITI Aayog's latest SDG India Index. Overall objective of this paper to understand this interesting subject, role of UN and how India is responsibly responding to maintain sustainability in this sector. [ABSTRACT FROM AUTHOR]

Spanning across Bangladesh and India, the Sundarban Delta consists of over a thousand islands, the majority of which are protected. These islands are important for the rich biodiversity and unique species found here. However, these islands are also at the forefront of climate change due to the impact of rising sea levels and extreme weather events. Therefore, we analyzed the long-term transformations in the land use land cover (LULC) between 1999 and 2020. We used a variety of geostatistical methods, including optimized hot spots cold spots and join count statistics, to examine the spatial patterns of changes in LULC across the study area. The results of our analysis revealed substantial changes in the spatial patterns of mangroves and pond aquaculture. The changes revealed a distinct north-south demarcation in spatial patterns, in the form of clustering of mangroves in the uninhabited islands located in the south and pond aquaculture clustered in the northern inhabited islands. The loss of area under mangroves was concentrated in the southern edges of the islands, which were most exposed to erosion in the open ocean. Nevertheless, we observed an increase in the area under mangroves in some of the northern riverine islands (17 km 2 ). In the case of pond aquaculture, it was mostly concentrated in inhabited islands in the north. Most of the expansions were concentrated in the Indian part of the delta (631 km 2 ). It is noteworthy that because of effective conservation measures, there was very limited overlap between mangroves and pond aquaculture, denoting the conversion of agricultural land to pond aquaculture instead of mangroves. Thus, the results of our study revealed the importance of local level conservation policies and anthropogenic activities, such as deforestation and local level disturbance like over-extraction of water and pollution, on the changing patterns of LULC across this unique, fragile ecosystem. Future studies may incorporate a finer resolution time series of LULC changes over time and space to enable more detailed analysis., (© 2024. The Author(s).)

Coastal wetland ecosystems make an important contribution to the global carbon pool, yet their extent is declining due to aquaculture-related land use changes. We conducted an extensive investigation into the carbon stock and area coverage of macrophytes in a tropical coastal Ramsar wetland, Kolleru in Andhra Pradesh, India. A total of 72 quadrats of size 1 × 1 m 2 were laid in the wetland, 19 species of macrophytes were collected and analyzed for carbon content using a CNHS analyzer. To assess changes in the wetland macrophytes, Normalized Difference Vegetation Index (NDVI) was estimated using Landsat time series data from 1975 to 2023. The importance value index (IVI) of macrophytes scored highest for the Ipomoea aquatica (41.4) and the lowest for Ottelia alismoides (1.9). Non-metric multidimensional scaling (NMDS) significantly (r = 0.1905, p = 0.0361) revealed a clear separation of macrophytes in ordination space. ANOVA indicated highly significant (p < 0.0001) variations in the carbon content of aboveground and belowground components of macrophytes. Among the different macrophytes, the highest carbon content was found in Phragmites karka (0.6 g. g -1 ) and the lowest was recorded in Utricularia stellaris (0.2 g. g -1 ). On an average, emergents in the Kolleru wetland sequester 1525 ± 181 g C m -2  yr -1 , rooted floating species sequester 858 ± 101 g C m -2  yr -1 , submerged macrophytes sequester 480 ± 60 g C m -2  yr -1 , and free-floating macrophytes sequester 221 ± 90 g C m -2  yr -1 . Land cover mapping revealed a decrease in spread of aquatic vegetation from 225.2 km 2 in 1975 to 100.6 km 2 in 2023. Although macrophytes are vital carbon sinks, the wetland conversion into fishponds has resulted in a loss of 55.3 % of carbon storage. Therefore, immediate restoration of macrophyte cover is vital for the proper functioning of carbon sequestration and mitigation of climate change impacts., Competing Interests: Declaration of competing interest The author declares that there is no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Reovirus designated as Mud crab reovirus (MCRV) is associated with the mass mortalities of mud crabs resulting in significant economic loss to crab and shrimp-mud crab polyculture farmers in the Nagayalanka, Krishna district, Andhra Pradesh. The 100 % chronic mass mortalities have been attributed to the outbreak of Mud crab reovirus (MCRV) in the polyculture farms. The moribund crabs showed autotomy, discoloration of carapace, loss of appetite, slow movement and loose gills. Histopathological observations of the infected mud crabs showed an atrophied hepatopancreas, complete degeneration of tissues along with viral inclusions in hepatopancreas, gills and muscles. Further analysis using Transmission electron microscopy (TEM), showed that the viral particles had a diameter of 70 nm and exhibited a non-enveloped, icosahedral shape arranged in a crystalline manner. The virus mainly infects the connective tissue of hepatopancreas, gills, muscle and develops in the cytoplasm. RT-PCR reconfirmed the presence of reovirus in the hepatopancreas of spontaneously infected mud crab Scylla serrata. The current study shows the importance of monitoring the MCRV prevalence in polyculture farms to minimize its spread and precautionary measures can be taken by screening the brooders from the crab hatchery and stocking of wild crabs without screening should be avoided in order to prevent MCRV outbreak., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The concept of "state fishes of India" highlights the importance and significance of the prioritized fish species distributed across various states within the country. This review article systematically documents the current status of state fishes from various perspectives, identifies the prevailing knowledge gaps, and also highlights the issues and strategic plans essential for the conservation and sustainable utilization of these valuable genetic resources. A total of 8357 publications were checked for the consolidated information on state fish species, and the appropriate items were selected under eight categories: biology, physiology and nutrition, aquaculture, habitat and environmental parameters, genetics and biotechnology, harvest and postharvest, fish health management, and others. The synthesized information was used to present the current status of research and development on state fish species. The knowledge gaps that are to be addressed are also depicted under the perspectives of fisheries management and conservation aquaculture. Based on the findings, strategic plans for the targeted conservation programmes are proposed and discussed under various in situ and ex situ conservation measures. Further, the departmental processes involved in the declaration, the importance of stakeholder involvement, namely, local communities and policymakers, in fostering effective conservation measures, and planning for utilization of these valuable fish genetic resources are also indicated., (© 2024 Fisheries Society of the British Isles.)

Numerous fresh and saline-water tropical aquaculture ponds that often can be significant sources super-saturation of CO2 towards the atmosphere are gradually increasing throughout the world. The role of salinity in regulating the chlorophyll-a and dissolved pCO2 in a freshwater aquaculture pond, situated in East Kolkata Wetlands, Eastern India, was tested using a microcosm conducted during summer (April-May) and winter (December–January) months. The effects of enhanced salinity to microcosm sets of 5, 10 and 15 ppt were monitored for nine consecutive days. pH, dissolved oxygen (DO), pCO2(water), chlorophyll-a, and gross primary productivity (GPP) were measured in-situ and every day during the entire microcosm. Enhanced salinity was hypothesised to alter the pCO2(water) and chl-a dynamics of this system significantly. Increasing salinity to 5 ppt would enhance the photosynthetic potential of the existing primary producers and reduce the pCO2(water) significantly, thus boosting the CO2 sink strength. This enhanced CO2 sink strength, accompanied with increased GPP and DO, was also observed in 10 ppt, only during summer; however, low temperature was found to abate the photosynthetic response during winter. Finally, in 15 ppt treatments, drastic chlorophyll-a reduction and extreme CO2 super-saturation showed the existing phytoplankton community cannot cope with such high salinity. [ABSTRACT FROM AUTHOR]

Water is essential for all living organisms in the universe. Chemicals can cause contamination in groundwater near aquacultural activity areas. Keeping in view the hectic aquacultural activity in surrounding locations of Akividu town in West Godavari District of AP, India, it is proposed to assess the chemical and microbial contamination of waters to suggest remedial measures to protect the quality of water for safeguarding the health of the public residing in the nearby habitations who consume these waters for drinking purposes. 16 Groundwater samples were collected and analyzed for assessing the physicochemical parameters viz., pH, Electrical conductivity (EC), Total Dissolved solids (TDS), Total hardness (TH), Total Alkalinity (TA), Na+, K+, Calcium, Magnesium, Chloride, Sulphate, Nitrate and Phosphate, Irrigation parameters like %Na, SAR, KR RSC, and microbial analysis. The study results revealed that the samples were contaminated chemically and also with pathogenic bacteria like Pseudomonas, Citrobacter freundii and Escherichia coli which can cause water-borne diseases. Further, a health survey was carried out to verify the adverse effects to be caused by the chemical and microbial contamination of water on people’s health. The health survey results indicated the sufferings of the people who consume this water for drinking and domestic purposes. The waters are to be treated accordingly to control the chemical and bacterial contamination by using the available treatment methodologies before considering them for drinking purposes. [ABSTRACT FROM AUTHOR]

Bacterial community structure is one of the essential components of aquaculture dynamics and plays an important role in maintaining wetland health. The present work is an effort to study the structure of bacterial communities in the world's largest sewage-fed fish farms, the East Kolkata Wetlands (EKWs), along with their predicted functional metabolic pathways and correlation with environmental variables. Sequencing data analysis revealed the abundance of genera such as Arcobacter (0–50%), Pseudomonas (0–15%), Sulfurospirillum (0–9%), Cloacibacterium (0–6%), hgcI clade (7–29%), C39 (0–9%), V6 (3–36%), Fluiivicola (1–6%) and Cyanobium (3–8%) in the EKWs. Further, water quality analysis of three treatment groups, i.e. Sewage, Sewage F-1 and Sewage F-2, revealed that dissolved oxygen (DO), biochemical oxygen demand (BOD) and chemical oxygen demand (COD) differed significantly and violated the standard prescribed norms (Central Pollution Control Board, CPCB, New Delhi) for fishery propagation and irrigation in India. Further, the correlation matrix analysis between the abundance of bacterial genera and environmental variables indicated that DO, BOD and COD were mainly responsible for bacterial community structure and their proliferation in the EKWs. Our results indicated that the abundance of genera such as Arcobacter, Pseudomonas, Sulfurospirillum and Cloacibacterium has an inverse relationship with BOD and COD. Our observations based on the bacterial community structure and deteriorated water quality indicate the ineffective functioning and poor management of this man-made constructed wetland. [ABSTRACT FROM AUTHOR]

This study was undertaken to evaluate the prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae in selected shrimp aquaculture farms (n = 37) in Kerala, South India and to characterize the isolates using molecular tools. Overall, a low prevalence of ESBL-producers was found in the farms, most likely due to the reduced antibiotic usage in the shrimp farming sector. Out of the 261 samples (77 shrimp and 92 each of water and sediment), 14 (5.4%) tested positive for ESBL- E. coli or ESBL- K. pneumoniae. A total of 32 ESBL- E. coli and 15 ESBL- K. pneumoniae were recovered from these samples. All ESBL isolates were cefotaxime-resistant with minimal inhibitory concentration (MIC) ≥32 μg/ml. Of all isolates, 9 (28.1%) E. coli and 13 (86.7%) K. pneumoniae showed simultaneous resistance to tetracycline, ciprofloxacin, and trimethoprim-sulfamethoxazole. PCR analysis identified CTX-M group 1 (bla CTX–M–15 ) as the predominant ESBL genotype in both E. coli (23, 71.9%) and K. pneumoniae (15, 100%). Other beta-lactamase genes detected were as follows: bla TEM and bla SHV (11 K. pneumoniae), bla CTX–M group 9 (9 E. coli), and bla CMY–2 (2 E. coli). Further screening for AMR genes identified tetA and tetB (13, 40.6%), sul1 (11, 34.4%), sul2 (9, 28.1%), catA and cmlA (11, 34.4%), qepA and aac(6 ′)-Ib-cr (9, 28.1%) and strAB and aadA1 (2, 6.3%) in E. coli , and qnrB (13, 86.7%), qnrS (3, 20%), oqxB (13, 86.7%), tetA (13, 86.7%), and sul2 (13, 86.7%) in K. pneumoniae isolates. Phylogenetic groups identified among E. coli isolates included B1 (4, 12.5%), B2 (6, 18.8%), C (10, 31.3%), D (3, 9.4%), and E (9, 28.1%). PCR-based replicon typing (PBRT) showed the predominance of IncFIA and IncFIB plasmids in E. coli ; however, in K. pneumoniae , the major replicon type detected was IncHI1. Invariably, all isolates of K. pneumoniae harbored virulence-associated genes viz., iutA , entB , and mrkD. Epidemiological typing by pulsed-field gel electrophoresis (PFGE) revealed that E. coli isolates recovered from different farms were genetically unrelated, whereas isolates of K. pneumoniae showed considerable genetic relatedness. In conclusion, our findings provide evidence that shrimp aquaculture environments can act as reservoirs of multi-drug resistant E. coli and K. pneumoniae. [ABSTRACT FROM AUTHOR]

Aquaculture is one of the important globally growing industries. It serves as an important food source of protein for human beings. With the expanding demand for the fish and their products it has become extremely important to improve the aquaculture practices. Aquaculture in India has witnessed huge mortalities caused by bacteria, viruses, fungi, nematodes etc. Aquatic weeds plants are harmful for aquaculture in many ways. Present study is aimed to overcome the disease caused by Aeromonas hydrophila (fish pathogenic bacteria) through feed supplementation of two aquatic weed plants (Azolla pinnata and Ceratophyllum demersum). The fish were divided into 6 groups: experimental groups (fish fed on supplementary feed at 5% and 2.5% concentration for individual plant and challenged with bacteria), positive control (fish fed on non-supplemented feed and challenged with bacteria) and negative control (fish fed on non-supplementary feed and not challenged with bacteria). It was observed that supplemented feed enhanced both cell mediated and humoral immunity in fish. Therefore, we advocate that feed formulated with incorporation of Azolla pinnata and Ceratophyllum demersum leaf powder at 5% and 2.5% could be used to prevent disease caused by A. hydrophila or can be used to enhance fish health by boosting its immune system. The results of this study also showed an improved digestibility in fish fed on supplemented feed. [Display omitted] • Use of Azolla pinnata and Ceratophyllum demersum in feed can reduce costs. • Improved health response to challenges with Aeromonas hydrophila. • Enhancement of both adaptive & cell mediated immunity. • Improved digestibility in fish fed on supplemented feed. [ABSTRACT FROM AUTHOR]

Shrimp aquaculture in India is synonymous with coastal aquaculture. Like other agricultural activities, it appropriates a wide range of environmental goods and services, and is vulnerable to impacts of climate change as the cultured animals are sensitive to various kinds of biotic and abiotic stressors. Climate change affects the shrimp aquaculture directly by extreme weather events and seasonal variations, and indirectly alter the primary and secondary productivity, structure and composition of the ecosystems or by influencing the availability of fishmeal, fish oil and other goods and services required for aquaculture farmers. The perceptions of farmers on the impacts of climate change on shrimp aquaculture in inland and coastal areas of Krishna District, Andhra Pradesh are discussed. Cyclone and flood were perceived by all the farmers, whereas irregular season, high temperature, heavy rain and drought were perceived by 79, 89, 91 and 5 % of farmers, respectively. Environmental, biological, and economic impacts of climate change drivers on aquaculture indicated 20 to 30 % loss due to seasonal variations and 50 to 100% loss due to extremely heavy rainfall, flood and cyclones. The economic risk rating was high with flood followed by the cyclone and the magnitude was more in coastal areas compared to inland areas. There is no universally applicable list of adaptation measures and need to be evaluated for individual aquaculture systems. Autonomous and planned adaptation measures to be implemented by farmers, researchers and policymakers are discussed for climate-resilient aquaculture. Planned adaptive measures are either at the primary level or non-existence, hence policy initiatives are required to formulate planned adaptive measures to enhance the adaptive capacity of the farmers. [ABSTRACT FROM AUTHOR]