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Light is an essential natural factor of fish growth and development. A light regime in indoor aquaculture is critical for sustainable fish production. This research aimed to investigate the effect of light intensity and photoperiod on the growth performance and stress response of Nile tilapia (Oreochromis niloticus), which is an important commercial species, in a recirculating aquaculture system (RAS). Fingerlings with an average weight of 5 ± 0.9 g were randomly assigned to nine 1.5 m3 tanks with 145 fish in each tank, cultured under different light intensities (1000, 2000, and 3000 lx) and photoperiods (12L:12D, 18L:6D, 24L:0D), and fed to apparent satiation twice a day for 160 days. The growth of tilapia subjected to 2000 lx was significantly better than that exposed to 1000 and 3000 lx (P 0.05). Light intensity and photoperiod manipulation did not cause a significant chronic stress response in tilapia. This study demonstrated that light intensity, especially at 2000 lx, and photoperiod manipulation could stimulate the growth of tilapia in the RAS and significantly affect economic profitability. This study also served as an important reference for tilapia indoor aquaculture.

Fish culture plays an important role in supplying high-quality proteins and omega-3 (n-3) long-chain polyunsaturated fatty acids. Aquaculture has been the fastest growing sector in agriculture. Fishmeal is an important component of commercial fish feeds, but ensuring a sustainable supply of fishmeal is in question. A good source of proteins in aquafeeds is insects. For the past 20 years, investigations have been carried out on insect meals as alternative sources for fishmeal. Thus far, the results on replacing fishmeal in feeding aquaculture species have been promising. However, some challenging issues including costs and scaling up of insect production remains. In this review, we aim to summarize the status of applying meals of eight insect species in formulated aquafeeds. We also discussed issues in replacing fishmeal in fish feeds with insect meals and listed some future research directions to make insect meals an important source of proteins for green, profitable and sustainable (GPS) aquaculture. It is certain that in the near future, large-scale insect farming and processing to produce insect meals as an ingredient of fish feeds will have positive impact on the sustainability and profitability of aquaculture.

The world wild fish stocks are being depleted in an ever-increasing speed. Aquaculture is the only way to ensure sufficient seafood for the world. Conventional aquaculture can be traced back to 4000 years in China and has been very successful in the past three decades. However, aquaculture has faced serious challenges, including only a few improved species, labour-intensiveness, environmental pollution, diseases and lack of traceability of products. Aquaculture needs disruptive technologies to increase fish production. Novel and disruptive technologies, including genome editing, artificial intelligence, offshore farming, recirculating aquaculture systems, alternative proteins and oils to replace fish meals and fish oils, oral vaccination, blockchain for marketing and internet of things, may provide solutions for sustainable and profitable aquaculture. This review briefly introduces these emerging and disruptive technologies to open up a forum for an in-depth discussion on how to integrate these technologies into aquaculture to improve its sustainability and profitability.

Like for other vertebrates, the fish microbiome is critical to the health of its host and has complex and dynamic interactions with the surrounding environment. Thus, the study of the fish microbiome can benefit from the new prospects gained by innovative biotechnological applications in human and other animals, that include manipulation of the associated microbial communities (to improve the health, productivity, and sustainability of fish production), in vitro gut simulators, synthetic microbial communities, and others. Here, we summarize the current state of knowledge on such biotechnological approaches to better understand and engineer the fish microbiome, as well as to advance our knowledge on host-microbes interactions. A particular focus is given to the most recent strategies for fish microbiome manipulation to improve fish health, food safety and environmental sustainability.

MDFRC item.Literature data are reviewed on the origin, distribution, economic benefits and impacts of common carp Cyprinus carpio L. in the Mediterranean region. Despite the ubiquity of domesticated and feral forms, wild populations of the genetically pure ancestor are still found in confined areas of Thrace and Northern Anatolia, and possibly in eastern parts of Greece. Introductions and translocations throughout the region from at least Roman times have been driven by a combination of historical, economic and cultural motives, which have contributed to the spread of the species into many freshwater systems. Although impacts have been either documented or suspected in most areas of distribution, and intervention by biomanipulation successfully implemented in some water bodies, there is a compelling need for more focused research in more vulnerable areas characterised by drier/warmer and overall more unpredictable climate conditions, which appear to favour successful common carp population dynamics. In contrast to large-scale (i.e. country-wide) control measures, likely to prove unfeasible because of the intrinsically high costs associated and/or loss of revenue from sport fishing and fisheries activities, localised (integrated) management actions, followed by post-intervention monitoring, are likely to benefit targeted water bodies for increased amenity and restoration value.

Bacterial diseases are the chief constraint in the aquculture industry. Among them Aeromonads causes majority of production loss in fresh water ornamental fish farming. Trend of application of probiotics in any aquaculture farm is being increasing to reduce the environmental degradation caused by chemical treatment methods. In this study, Aeromonas veronii was isolated from diseased koi carp and its virulency was re-confirmed with mortality rate of 73.33 % in koi carp. Susceptibility of A. veronii to commercial probiotic mixture of Bacillus species was proved by in vitro assay where zone of inhibition of 22.67 ± 0.6 mm diameter was observed at 108 CFU mL−1. Bacillus probiotic mixture at 108 CFU g−1 maintained the gut morphology with good goblet cell count against A. veronii infection in koi carp. Thus, severe production loss due to A. veronii in ornamental fish farms can be controlled by probiotic dietary supplementation.

Ginseng (Ge) is one of the most famous and precious consumed herbal medicines around the world. Ge plant roots have many advantages regarded as important in increasing fish production. Thus, the present study was conducted to investigate the possibility of using different levels (0.0, 100, and 200 mg/kg diet) of Ge as a reproductive enhancer agent for African catfish, Clarias gariepinus males. Results revealed that fish fed 200 mg Ge/kg diet significantly (P ˂ 0.05) increased growth performance, feed efficiency, gonado-somatic index, hematological parameters, serum follicle-stimulating hormone, total antioxidant capacity, sperm quality parameters, and ultrastructure of spermatozoa, as well as led to positively improved of the histological structure of the testes tissue compared to other treatments. Based on the obtained findings, it could be concluded that the effective use of dietary Ge at a level of 200 mg/kg as a promising reproductive agent for adult African catfish males consequently led to the sustainability of aquaculture for African catfish.

Water reuse in fish farming is a practice that has been spreading significantly, therefore requiring more efficient and vigorous treatment systems. The objective of this study was to evaluate the potential reuse of aquaculture wastewater after being treated in horizontal subsurface flow constructed wetlands (HSSF-CW). Three HSSF-CWs with dimensions of 1.0 m in width, 3.0 m in length, and 0.30 m in depth were evaluated. One HSSF-CW had stargrass (Cynodon nlemfuensis) cultivated; the other had cattail (Typha latifolia), and the third was used as a control, where there was no cultivation. The wastewater was provided from three Nile tilapia breeding tanks, which recirculated the entire system after going through the HSSF-CW. The following variables were determined every five days at the HSSF-CW influent and effluent: temperature, pH, turbidity, electrical conductivity, redox potential, dissolved oxygen, ammonium, and nitrate. The treatment in the HSSF-CW allowed the reuse of aquaculture wastewater as it provides water quality levels according to the recommendation for Nile tilapia breeding. Furthermore, the water quality parameters monitored in HSSF-CW effluent remained within limits established by CONAMA Resolution No. 357/2005 for aquaculture and fishing activity. Water reuse in fish farming is a practice that has been spreading significantly, therefore requiring more efficient and vigorous treatment systems. The objective of this study was to evaluate the potential reuse of aquaculture wastewater after being treated in horizontal subsurface flow constructed wetlands (HSSF-CW). Three HSSF-CWs with dimensions of 1.0 m in width, 3.0 m in length, and 0.30 m in depth were evaluated. One HSSF-CW had stargrass (Cynodon nlemfuensis) cultivated; the other had cattail (Typha latifolia), and the third was used as a control, where there was no cultivation. The wastewater was provided from three Nile tilapia breeding tanks, which recirculated the entire system after going through the HSSF-CW. The following variables were determined every five days at the HSSF-CW influent and effluent: temperature, pH, turbidity, electrical conductivity, redox potential, dissolved oxygen, ammonium, and nitrate. The treatment in the HSSF-CW allowed the reuse of aquaculture wastewater as it provides water quality levels according to the recommendation for Nile tilapia breeding. Furthermore, the water quality parameters monitored in HSSF-CW effluent remained within limits established by CONAMA Resolution No. 357/2005 for aquaculture and fishing activity.

Cardiac abnormalities may pose a threat to salmonid aquaculture due to their potential detrimental effect on fish health and welfare. The teleost heart is an extremely plastic organ with important morphological differences between wild and farmed fish that include ventricular shape, alignment of the bulbus arteriosus and epicardial fat deposition. However, little is known about how different factors and interactions among them may affect cardiac morphology of Atlantic salmon. To determine whether rearing temperature could induce cardiac malformations in large Tasmanian Atlantic salmon, we examined a range of cardiac morphology indicators and growth parameters in a population of 1-2 kg seawater salmon (n = 60 temperature-1 diet-1 ) exposed to control and elevated temperatures of 15 and 19°C, respectively, while fed one of two commercial feeds with different dietary energy levels. Most fish possessed conspicuous fat around the heart with a tendency towards a rounded ventricle and a more obtuse angle of the bulbus arteriosus. However, fish showed no significant differences in heart shape and bulbus alignment in relation to water temperature and dietary energy. These results suggest that cardiac morphology of large Atlantic salmon is unlikely to be affected by rearing temperature and dietary energy during the grow-out phase.

Catfish have become an important contributor to fish production in Indonesia. Catfish consumption in Indonesia always increases every year. To meet the demand for catfish consumption, it was carried out with an intensive aquaculture system. However, the high cost of feed has been identified as a significant constraint in catfish farming. Efforts to increase catfish growth are needed to reduce feed costs, one of the efforts is by probiotic supplementation through the feed. This study was carried out to determine the best dose of probiotic rabal dried addition to increasing catfish growth. The experiment used four treatments and three replications. Probiotic rabal dried doses: 0% of feed (A)/feed (control), 5% of feed (B), 10% of feed (C), and (D) 15% of were used as treatment. The feed was given ad-satiation with a frequency of feeding three times a day. Observations were made for 45 days. The results indicated that the B treatment of 5% of feed gave the best absolute weight growth and feed conversion ratio. While catfish fish survival rate was not significantly different on all treatments.

Fish farming is considered an important agricultural activity that is capable of ending nutritional deficiencies of the world and contributing to poverty reduction. Its proponents argue that aquaculture will meet the food security needs of millions of people in developing countries who will benefit from relatively inexpensive protein, while depleted capture fisheries are allowed to replenish. Egypt is Africa's leading aquaculture country, followed by Nigeria with similar production systems. The dominant species of fish cultured in Egypt and Nigeria are Tilapia and African catfish, respectively. The aquaculture industries in these two counties are very promising, as there is a presence of water bodies, some institutional commitment, and high demand for fish among others. Despite some gains made by the countries and the huge potential of the aquaculture sector, it is however bedeviled with constraints such as low technology adoption, inadequate supply of fingerlings, high cost of fish feed, etc. This work is an overview of the aquaculture sectors of Egypt and Nigeria, which includes the production systems, prospects, and potentials of the sector and the constraints that affect aquaculture.

The problem of sewage disposal has received great attention worldwide. The raw sewage contains a variety of high inorganic and organic matters that affect natural water environment. To mitigate such problem, sewage may be recycled through aquaculture practice. Sewage recycling in aquaculture enhances water productivity through nutrients input. Proper loading of sewage ensures viable aquaculture; otherwise, fish mortality occurs due to poor water quality. To optimize sewage application, two different experiments were conducted, each with four treatments. In both experiments, three fish species namely rohu (Labeo rohita Hamilton, 1822), mrigal (Cirrhinus mrigala Hamilton, 1822), and bata (Labeo bata Hamilton, 1822) were tested in triplicate in FRP (Fibre-Reinforced Plastic) tanks. Different sewage concentrations (0, 25%, 50% and 75%) used in first experiment were prepared by mixing freshwater, showing Biochemical Oxygen Demand (BOD) 2.0 ± 0.4 mg/L, 10.8 ± 1.4 mg/L, 19.6 ± 1.5 mg/L and 41.6 ± 2.58 mg/L, respectively. After 30 days rearing, results showed ≥75% fish survival in sewage concentrations up to 50% with BOD level 19.6 ± 1.5 mg/L. Less than 50% fish survived in 75% sewage concentration, with BOD level as 41.6 ± 2.58 mg/L. The second experiment was conducted for 90 days considering 50% sewage concentration as basal dose with BOD level as 19.6 mg/L as an acceptable limit for fish survival. Split doses of sewage were applied in T1, T2 and T3 treatments fortnightly, weekly and semi-weekly intervals, while single dose was used in C (control) treatment. Application of split doses resulted better hydro-biological changes, including nutrients recovery, in T1, T2 and T3 than that of single dose in control. Fish growth plotted with net primary productivity (NPP), phytoplankton and zooplankton densities exhibited positive correlations in T2 (12 doses) and T3 (24 doses), considered as optimal doses to ensure better water productivity for desirable fish production than sewage with single dose or limited doses (6 doses).

Aquaculture industry in Malaysia involves culture of many fish species of either fresh or brackish water origin and among the important fish species are Snakehead, Tilapia and Catfish. There is a substantial culture of these fish in Malaysia nowadays, though there are not one hundred percent native fish species but their presence in Malaysia is getting closer to over several decades and for almost a decade now, these species had been among the highest finfish produced in either fresh or brackish waters. As the global aquaculture production continue growing in order to meet up with ever increasing fish demand, especially as fish from capture has levelled off and makes an increase in aquaculture production as the only hope to meet the demand for fish, one of suggested ways in culturing them is by venturing into integrated fish farming. Integrated fish farming of different species is a practice which links together two or more normally separate farming systems, whereby the fish from different species become subsystems of a whole farming system. Although integrated fish farming may not be huge globally based on the available official statistical data but it is becoming important industry in Malaysia and neighboring countries. This review discussed briefly about the integrated fish farming of three commercially popular species (Snakehead, Tilapia and Catfish) in Malaysia and neighboring countries.

Aquaculture production has seen much increase in Nigeria in recent times due to the rise in fish farming occasioned by the availability of water and materials for setting up, the profit turn-over, increase in demand for fish, and the effort to curb the rising youth unemployment rate. However, this massive surge of interest in aquaculture and fish farming is accompanied by the challenge of pollution as the effluent from aquacultural settings gets discharged into nearby water bodies hence the need for remediation. Aquatic plants have been used to remediate polluted water bodies and possess many advantages over other methods. Therefore, this study aimed to investigate the effectiveness of Eichhornia crassipes in the clean-up of aquaculture effluent. Wastewater collected from a commercial fish pond in Benin City, Nigeria, were divided into two treatment groups. One group was diluted with an equal volume of distilled water (50%), and the other group consisted of 100% wastewater. Distilled water was used as a control (0%). The samples were treated with Eichhornia crassipes for 14 days, following which samples were collected for physicochemical analysis. The result showed that E. crassipes reduced significantly the pH from 7.44 to 5.98 and 7.28 to 6.10 in the 50% and 100% effluent samples, respectively. The removal efficiency of E. crassipes in the 100% effluent sample was 69% for phosphate, and 94% for nitrate. The study suggests that E. crassipes may be effective in improving the quality of aquaculture wastewater.

The growth and survival are considered as the crucial factors that should be taken into consideration in any aquaculture system. The experiment was aimed to evaluate the growth performance and subsequent survival rate of the rohu (Labeo rohita) and tilapia (Oreochromis niloticus). It is important to evaluate the growth responses in relation to Feed Conversion Ratio (FCR) and assessment of the total production of the culture unit. As per the recommended stocking density of 320 fishes/decimal in intensive aquaculture system 8 fry per tank was released to assess the growth performance, survival and production of both rohu (T1) and tilapia (T2). During experimental period, there were three replications for each treatment and feed was supplied at the rate of 12%, 8%, and 4% of the body weight of rohu and 20%, 15%, and 10% of the body weight of tilapia in 1st, 2nd and 3rd month for T1 and T2, respectively. The initial weight of individual tilapia was 7.52±1.81 gm and 14.75±0.19 gm for T1 and T2, respectively. The mean final weight was 44.01±4.03 g for T1 and 139.94±1.29 for T2. The weight gains of fish were 36.49±4.09 gm and 125.19±1.29 gm for T1 and T2, respectively. The mean percent weight gain of tilapia was higher in T2 (1715.05±0.00) than T1 (485.23±0.00). The Specific Growth Rates (SGR) of T1 and T2 were found 4.98±2.28 and 6.26 ±3.83, respectively. There was significant difference (p>0.05) in term of SGR between the treatments. Feed Conversion Ratio (FCR) in T1 and T2 were 2.86±0.14 and 2.23±0.18, respectively. Higher total production was obtained in T2 (1119.52 gm) than T1 (278.19 gm) with 100% survival in both the treatments. The water quality parameters for both of the species were within the suitable range. This study reveals a promising arena for fish culture in tank-based intensive aquaculture system as an efficient way of overcoming the scarcity of water and land. This culture system may be an excellent way of producing fish in a small parcel of land with securing the propitious production and expected outcomes within a limited period of time.

Skeletal deformities in cultured fish are known worldwide and it had affected the survival, growth and appearance of the fish which contribute to production loss. Clarias gariepinus is known as number one farmed fish in Malaysia. C. gariepinus also effected in these deformities especially in cultured species. The objectives of this study are to identify the skeletal deformities that occur in juvenile stages and to compare the bone structure between the normal and deformed fish. A total of 50 juveniles’ fish were collected from Aquaculture Extension and Community Centre Machang, Kelantan. The juvenile was measured before undergo staining process. The fish were starved for one day then fixed in 70% ethanol for two weeks. The fish were then stained with alizarin red S for cartilage and Alcian blue for bone. The specimens were photographed in order to observe the deformities. The data showed only 13.0% juveniles have skeletal deformities, 10.9% with lordosis and 2.2% scoliosis. The cause of the deformities may be due to the heterogenous growth but other factors might also contribute to the problem. As the conclusion, the skeletal deformities observed in juvenile C. gariepinus were detected with the whole-mount staining method ranged from size 7.3 and 26.0 cm in total length. This study shows there is heterogenous growth rearing at low percentage even from skilled farm. Further study should concentrate on hidden factors that affected the deformity rate and mineralization of the juvenile fish.

The Covid-19 pandemic has an impact in all fields, namely in terms of health, social, economic, and food. Reduced income or even job loss to cause a decrease in the ability to meet basic needs, namely family food needs. Corporate Social Responsibility (CSR) of Pertamina Corporation Integrated Terminal Jakarta initiated collaboration between community groups and various stakeholders through the integration of the budikdamber system and the development of processed product innovations done in Rawa Badak Selatan Village, Koja District, North Jakarta as the Area 1 Company's Ring. The development of processed innovation products is carried out together with the Bunda Koja group by carrying out all contain catfish product (ACE) activities. ACE's budikdamber activities are empowered by cultivating fish and vegetables in buckets carried out in several yards of residents of the Rawa Badak Selatan Village. This activity is expected to contribute to the community’s resilience in the face of pandemics by increasing knowledge and skills in developing mental systems and their processed products. The implementation of activities is carried out by training methods and the application of mentoring. The community generally feels helped because the process of making processed and ACE budikdamber is empowered to facilitate for the community to get nutritious food. This activity also has an impact on improving nutrition and socioeconomics of toddler parents, through training in nutritious catfish processed products, toddler mothers can learn to understand the importance of nutritious food for toddlers.

he purpose of this study is to describe specifically the related reality of traditional to digital trade: the adoption of social media in the trade of fish cultivation during the Pandemic in palangka raya city. Fish harvests and fish catches in the Kahayan river usually people sell them in the market and offer to the surrounding residents through traditional buying and selling, when the pandemic makes people turn to digital transactions. Digital media that is often used is Facebook and Whatsapp media as a promotional tool as well as a digital buying and selling tool conducted by fish farmers. This study uses qualitative method with phenomenological approach. Data is collected through three ways, namely observation, interview, and documentary studies. This research found that traditional to digital trade: the adoption of social media in the trade of fish cultivation during the Pandemic in palangka raya city, where social media is quite effective as a tool to develop income from sales on social media, especially in the trading activities of fish cultivation.Keywords: Transactions, digital transactions and fish farming products

The objective of this study was to evaluate biochemical parameters and histopathology of liver in Matrinxã (Brycon cephalus) and Pacu (Piaractus mesopotamicus) fish chronically exposed to dietary aflatoxins. Fish feed was artificially contaminated with aflatoxins and the treatments were: Control – feed without toxin; Treatment A – feed + 10 μg aflatoxin B1 (AFB1)/kg; Treatment B – feed + 20 μg AFB1/kg; and Treatment C – feed + 50 μg AFB1/kg. Matrinxã and Pacu juvenile fish were placed in tanks for 180 days. Five experimental units per treatment were monthly sampled and submitted to blood collection and removal of hepatic tissue. Thus, twenty blood and liver samples for each species were collected monthly, adding up to 240 samples analysed. To verify biochemical changes, analyses included total proteins, albumin, globulins, aspartate aminotransferase (AST) and alkaline phosphatase (ALP). The hepatic tissue was examined microscopically and the slides presenting histopathological changes were photo-documented. There was effect of treatment (P0.05) was observed in Pacu. A reduction (P1.

With the continuous expansion of aquaculture scale and density, contemporary aquaculture methods have been forced to overproduce resulting in the accelerated imbalance rate of water environment, the frequent occurrence of fish diseases, and the decline of aquatic product quality. Moreover, due to the fact that the average age profile of agricultural workers in many parts of the world are on the higher side, fishery production will face the dilemma of shortage of labor, and aquaculture methods are in urgent need of change. Modern information technology has gradually penetrated into various fields of agriculture, and the concept of intelligent fish farm has also begun to take shape. The intelligent fish farm tries to deal with the precise work of increasing oxygen, optimizing feeding, reducing disease incidences, and accurately harvesting through the idea of “replacing human with machine,” so as to liberate the manpower completely and realize the green and sustainable aquaculture. This paper reviews the application of fishery intelligent equipment, IoT, edge computing, 5G, and artificial intelligence algorithms in modern aquaculture, and analyzes the existing problems and future development prospects. Meanwhile, based on different business requirements, the design frameworks for key functional modules in the construction of intelligent fish farm are proposed.

The annual increase in Egyptian & Global fish production is mainly due to annual increase in fish production from aquaculture compared to natural fisheries during the study period (2000-2018), and also increasing the relative importance of fish production from aquaculture compared to natural fisheries since 2003 and 2013 in the world and Egypt, respectively. Fish Aquaculture patterns vary according to water types used in Aquaculture (freshwater, brackish water, salt water). in World, The freshwater aquaculture production is higher (60.1%) than the salt water aquaculture production (31.5%) and the brackish water (8.4%) respectively, but in Egypt, Fish that are cultured in fresh water (Tilapia, Catfishes, Carps, Bagrus spp, and Nile perch) contribute about 77.72% of the average fish production from aquaculture during the study period (2000-2018), which is estimated at about 648.8 thousand tons, while fish are farmed in brackish water, which are represented by the mullets family contributed about 18.77%, while the fish that are cultured in salt water (Seabream, Seabass, Meager, Shrimp, Eels, and Gropers) contribute very little due to the novelty of this type of aquaculture in Egypt, estimated about 3.51% Average fish production from aquaculture during the study period. Aquaculture in Egypt contributes about 80.7% of the total Egyptian fish production in 2018, which reflects its important role in filling the fish gap in Egypt. The most important determinants affecting aquaculture fish production in Egypt during the study period (2000-2018) are: (1) The average price per ton of cultured fish: increase in the average price per ton of farmed fish by 1% leads to an increase in the amount of annual aquaculture fish production about 1.3%, (2) the number of freshwater frys and fingerlings produced in private hatcheries: by increasing the number of freshwater frys and fingerlings produced in private hatcheries by 10%, leads to an increase in the amount of annual aquaculture fish production about 3.0%.

Sustainable development of fresh water (FW) aquaculture requires minimal environmental impact, by reducing the waste discharged into the surrounding waters. To assess the water quality status and impact of flow-through trout farming in the Louros river (NW Greece), a seasonal evaluation of the trout production in the river was performed. Seasonal samples of river water entering and discharged were obtained to monitor some water quality parameters. The parameters were temperature, pH, ammonium, phosphate, dissolved oxygen (DO), biochemical oxygen demand (BOD5), electrical conductivity (EC), total dissolved solids (TDS), total nitrogen (TN), and total phosphorus (TP) of flow-through trout farms alongside the river. All monitored parameters indicated minimal environmental impact of the fish farms; pH ranged from 7.57 to 8.03, TDS ranged from 151.43 to 242.56 mg/L, DO ranged from 6.28 to 9.16 mg O2/L, BOD ranged from 0 to 2 mg O2/L. As for the nutrients, mean values were below each limit set for freshwater systems. NH4-N ranged from 0 to 0.28 mg/L, and PO4-P ranged from 0.15 to 0.42 mg/L. Based on the comparison of water quality parameters in the outlets and on the Environmental Impacts and Environmental Quality Standards (EQS), it can be concluded that trout fish farms had no significant environmental impact on the river water quality during any of the tested seasons. All parameters presented strong increasing trends during spring and summer and low decreasing trends in autumn and winter. In conclusion, the results indicated minimal aquaculture impact on river Louros water quality.

Background: Uttar Pradesh is India’s most populous state having 1662 lakh population as per 2001 census, against 16.2% of India’s population with enough fisheries resources in the form of community ponds, tanks with dominance of rivers and man-made reservoirs. Five blocks (Koraon, Shankargarh, Karchhana, Handia, and Jasara) from Prayagraj were taken for study during the period of 1st December,2020 - 31st May,2021. Aim: To examine the fish production of different size of fish farm groups. Methodology: A study was conducted in the Prayagraj district of Uttar Pradesh. A total of 80 fish farmers were selected randomly from five blocks (Koraon, Shankargarh, Karchhana, Handia, and Jasara) and a pre-structured questionnaire was used to collect the data from the fish farmers. The fish farmers were classified into three categories on the basis of the size of pond area viz. small farmer: up to 0.125 ha., medium farmer: 0.125 ha to 0.250 ha., and large farmer: above 0.250 ha. Result: The Study showed that, various independent variables of production like fingerlings, manures, feeds, and labor were being analysed in accordance with their respective sample of fish ponds and it is concluded that all of the independent variables affected the fish production differently. Using Cobb Douglas production function, 73% variation in gross value return from explanatory variables was observed in first size-group. Effect of Improved variety fingerlings was negative and coefficient of elasticity for human labor was positive but both impacted fish production significantly. A variation of 41.6% in gross value return was observed from second size group. Human labor impacted fish production significantly and its coefficient of elasticity was positive. Further, 45.7% of variation in gross value return was in third size group. Human labor and manure both had a significant effect, and their coefficients of elasticity was positive and negative respectively. Coefficient of multiple determination was 76.6% indicating variation in gross value return from independent variable from all farm’s situations. Pond area and human labor variables had positive coefficient of elasticity but for improved fingerlings it was negative and all effected fish production significantly. Conclusion: It was concluded that there is a need to further engage the fish farmers in the fish production practices and provide them with sufficient inputs of production like fingerlings, manures, feeds, and labor so that the farmers can boost the fish production in the study area.

Skeletal abnormalities in farmed fish are one of the main problems that negatively affect the production enterprises in terms of economic, biological and animal health. Fish with skeletal deformities in hatcheries are considered as non-economic individuals and are therefore detected and removed manually from the production tanks, which is a time consuming and laborious work for the facilities. Since the formation of abnormalities in the skeletal structure of the fish during the early growth period cause reduced swimming ability or speed that prevent fish to compete during feeding. Further, since deformed fish has no market value, even the share of a small amount of feed among deformed fish will reduce the feed conversion for the market targeted individuals within the culture tank that in terms may increase the production cost per fish. Therefore, in culture conditions it is important to remove the deformed fish from the tank environment by quickly determining those fellows at the early stage of growth. The present study evaluates the effects of water velocity on swimming behavior of juvenile seabass (Dicentrarchus labrax) and provides a solution for a rapid identification -and mechanical removal of deformed fish from the culture environment by using swimming speed slowdown -and behavioral differences as an indicator of deformation.

Elopichthys bambusa is an economically important freshwater fish with high nutritional value. In this study, we compared domesticated and wild fish at the physiological, biochemical, histological, and molecular levels to better understand the changes that occur in farmed fish in order to provide ideas about how to optimize the artificial feed formulation used in aquaculture of this species. Water, ash, and crude protein contents did not differ significantly between the two groups. The methionine and glutamic acid contents were 20% and 13.4% higher in the domesticated group than that in the wild group, respectively. Twenty-three types of fatty acids were detected in the wild group compared to 11 in the domesticated group. The iron content in the domesticated group was higher than that in the wild group. The blood index values did not differ significantly between the two groups, except for alanine aminotransferase (ALT), total protein (TP), and globulin (GLO) contents. The ALT content in the wild group was significantly higher and the TP and GLO contents were significantly lower than those in the domesticated group. Histologically, significant differences in the numbers of folds, villi, and goblet cells were detected between the two groups. The expression of t1r1 and t1r3 in the intestines and gills of the domesticated group was significantly lower than that of the wild group. This study provides an important theoretical basis for the reproduction and breeding studies and the quality identification of domesticated Elopichthys bambusa. It will promote the development of large-scale farming of Elopichthys bambusa.

Arsenic-contaminated food including farmed fish is one of the main routes of human exposure. Fish farmed in contaminated environment accumulates arsenic in different tissues with great variability. Thus, it is utmost important to quantify the risk associated with different farmed fish species in arsenic-contaminated aquaculture systems. In the present study, arsenic content was measured in twelve fish species (Labeo rohita, L. catla, Cirrhinus mrigala, Oreochromis niloticus, O. mossambicus, Liza tade, Puntius javanicus, L. calbasu, Glossogobius giuris, Macrobrachium rosenbergii, Ctenopharyngodon idella, and Bellamya bengalensis (gastropod)) collected from arsenic-contaminated aquaculture systems. Among the studied finfishes, C. idella was found to accumulate the lowest amount of arsenic (

This study was primarily aimed at prospective role of agricultural extension in the field of fish farming in Rashed and Edko district in Behiera Governorate. The questionnaire was used in a personal interview to update the field data from the 200 research samples from the owners of community fish farms in Rashed and Edko district. The data were collected in more than one year, and statistical methods used percentages, frequency and relative distribution tables, arithmetic means, standard deviation, simple correlation coefficient, and multiple Step Wise regression coefficient using Spss program. The most important results were as follows: - 49.5% of researchers had a low overall level of knowledge, compared with 39,5% had an average overall level of knowledge, while 11% had a high overall level of knowledge. There is no doubt that the general level of knowledge of the researchers may affect the amount of production from these farms. - The most important problems facing the researchers are the high costs of establishing a fish farm, followed by the lack of physical capacity of the farmers. The low price of fish in marketing, the lack of an independent financial source to finance the fish farming process, frequent problems with taxation, high rent prices for fish land, unclear role of extension in the development and development of fish farms for the establishment of extension farms; The absence of the vital role of the Public Authority for the Development of Fish Resources, the failure to supply extension publications to farmers; Lack of inputs, difficulty in obtaining good crops, the appearance of many diseases in fish during breeding. water scarcity and lack of availability throughout the year, lack of water for fish farming. low feed quality, high feed price, low fish harvest, and finally no intensive farming systems in farming.

Access to credit is a major limitation for small-scale fish farmers in Bangladesh in pursuing their fish farming activities. One attempted remedy is that NGOs have created microcredit facilities to...

Tambaqui, a species native to the Amazon and Orinoco Basins and their tributaries, has a history marked by biological resilience that makes this species a model for studies focused on ecology, physiology, and fish farming. In addition, it is of economic interest, due to its favorable characteristics for production in farms and its unique flavor. As the tambaqui responds in a unique way to several environmental disturbances of natural origin, the species is often used in environmental studies. Some of these studies have been revisited in this review. We revised aspects related to its natural history, habitats and geographic distribution, physiological and biochemical adaptations, and zootechnical performance. The extraordinary adaptation of the tambaqui is the fast expansion of its lower lip when exposed to low oxygen availability that is improved simultaneously with other adjustments. The resilience of this species to significant alterations in water pH is also surprising, and is incomparable with that of other species, as only when it is exposed to pH 3.5, does the tambaqui begin to present physiological-biochemical disturbances. The analysis of the gene expression of tambaqui specimens under different experimental conditions has shed light on the adaptive mechanisms used by this unique Amazonian species. In this sense, this review sought to gather information regarding the tambaqui, and its many biological features employed to survive environmental challenges.

Several reports show that aquaculture is the fastest food-producing sector globally, contributing nearly half of global fish production from all sectors. However, there has been a steady decline in...

As aquaculture continues to grow and intensify, there is an increasing public concern over the welfare of farmed fish. Stress and production-related pathologies and repressed growth are examples of the challenges facing aquaculture, and their impacts could be minimised by effective identification of the early signs of impaired welfare. Many welfare monitoring methods have been recommended; however, continuous and reliable welfare monitoring in aquaculture is not yet widespread and commonplace. The aim of this scoping review was to present an overview of the most recent developments in fish welfare assessments with a specific focus on practical translation to the aquaculture industry. A keyword-based search was undertaken to identify peer-reviewed papers published between 2014 and 2020 in which a novel method with the potential to be used for the assessment of fish welfare in aquaculture was introduced. The results were sorted into two categories: non-invasive and invasive methods. All methods were assessed for their advantages and disadvantages, potential applicability to aquaculture. Invasive methods were also ranked on their degree of impact. It is concluded that increased interest into fish welfare, in combination with more intelligent modern technology, has resulted in the development of newer and more refined alternatives to traditional methods of welfare assessment such as behaviour monitoring by 2D cameras and plasma cortisol evaluation. Although, in many cases, more research is needed before these methods are suitable for widespread industry use, studies that focus on increasing the precision, automation and practical applicability of these methods are a promising avenue for future research.

Precision fish farming is an emerging concept in aquaculture research and industry, which combines new technologies and data processing methods to enable data-based decision making in fish farming. The concept is based on the automated monitoring of fish, infrastructure, and the environment ideally by contactless methods. The identification of individual fish of the same species within the cultivated group is critical for individualized treatment, biomass estimation and fish state determination. A few studies have shown that fish body patterns can be used for individual identification, but no system for the automation of this exists. We introduced a methodology for fully automatic Atlantic salmon (Salmo salar) individual identification according to the dot patterns on the skin. The method was tested for 328 individuals, with identification accuracy of 100%. We also studied the long-term stability of the patterns (aging) for individual identification over a period of 6 months. The identification accuracy was 100% for 30 fish (out of water images). The methodology can be adapted to any fish species with dot skin patterns. We proved that the methodology can be used as a non-invasive substitute for invasive fish tagging. The non-invasive fish identification opens new posiblities to maintain the fish individually and not as a fish school which is impossible with current invasive fish tagging.

AIM The aims of this study were to screen an antagonistic probiotic for the prevention and control of bacterial diseases in snakehead fish and to evaluate the antimicrobial activities, biosafety and biocontrol effect of the antagonistic strain. METHODS AND RESULTS In this study, the WLYS23 strain exhibiting the most effective antagonistic properties against several fish pathogens was selected from the intestine of healthy snakehead fish. The strain was identified as Bacillus velezensis based on morphological, physiological and biochemical characteristics, and phylogenetic analysis. This strain showed amylase, cellulase, protease and lipase activities according to extracellular enzyme activity assays. Moreover, the cell-free extract of the WLYS23 strain exhibited strong antibacterial activity, with MICs of ≤64 μg ml-1 for most fish pathogens. Additionally, the cell-free extract was heat and pH stable, and resistant to protease, whereas their antimicrobial activities were significantly influenced by metal ions at high concentration. The WLYS23 strain and its cell-free extract were safe for snakehead and zebrafish. The disease resistance of snakehead fish was significantly increased following administration of the WLYS23 strain and its cell-free extract respectively. The complete genome of the WLYS23 strain was sequenced and found to harbour seven gene clusters encoding secondary metabolites with antimicrobial activity. CONCLUSION The WLYS23 strain possesses great potential as a biocontrol agent, which can be commercially developed to improve disease control in freshwater aquaculture. SIGNIFICANCE AND IMPACT OF THE STUDY Snakehead fish are important commercially farmed fish worldwide. However, the bacterial diseases caused by Aeromonas sp. and Nocardia seriolae in farmed snakehead fish lead to huge economic losses. Safe, economical and efficient probiotics are limited to prevent and control these diseases. Here, we provide a promising biocontrol agent with antagonistic activity against bacterial diseases of snakehead.

Viable threats from waste-fed aquaculture have become a genuine subject of discussion presumably since the initiation of such fishery. An aquaculture-based sewage treatment system, blending fish as biological component was assessed in Bandipur, Titagarh, North 24 Parganas, West Bengal, India. The 5 MLD (million litres per day) system receiving domestic sewage flow comprised of anaerobic ponds (areas-0.7 ha, depths-2.5m), facultative ponds (areas-4.8 ha, depths-1.5m) and maturation ponds (areas-4.8 ha, depths-1m). The observation revealed substantial aptitude of the system for biological sewage treatment, with respect to reduction of ammonia nitrogen, BOD (Biological oxygen demand) and COD (Chemical Oxygen Demand). The TVC (Total Viable Count) and enteric bacterial counts were detected in higher numbers from water and fish. Some of the members customarily recovered in this study like Vibrio were established fish and human pathogens. Counts of faecal coliforms in fish culture ponds were found to outstrip the World Health Organization (WHO) standards of ≤103 faecal coliforms per 100 ml of water to be used in aquaculture. High concentrations of pathogenic bacteria were reported to be present in fish even at low numbers of indicatory bacteria. Estimated risk of bacteriological infection of fish for most of the times crossed the guide line proposed by international commission on the microbiological specification of foods (1995). Public health risks associated from fish and fishery products of Bandipur sewage fed farm clearly indicate infelicity of wastewater treatment along with inappropriateness of treated waste water to be reused in aquaculture.

Fish management systems have an important role in fish farming. One aspect of fish management is water quality which includes several things such as temperature, pH, oxygen levels and also feeding. So far, monitoring of water quality and feeding of fish has been done manually. This study aims to design a control-monitoring system for oxygen levels, pH, temperature and automatic feeding based on IoT. The reading data from the sensor and also the RTC will be forwarded by the microcontroller to the server to be displayed to the user. This system is automated with actuators in the form of aerators and motors, so that feeding and adding oxygen levels to the pond will be automatically carried out by the microcontroller. The results of this study indicate the system can work, temperature data, oxygen levels, pH can be monitored through the server and feeding can also be done.

The review considers probable ways to overcome the deficiency of eicosapentaenoic and docosahexaenoic acids in the human diet through the rational development of aquaculture. Currently, aquaculture is not a producer, but a consumer of polyunsaturated fatty acids, since it is based on feed, the main components of which are fishmeal and fish oil obtained from commercial catches. It is proposed to transform farmed fish from a consumer to producer of these polyunsaturated fatty acids. The source of production of eicosapentaenoic and docosahexaenoic acids in aquaculture can be their synthesis by fish from short-chain α-linolenic acid contained in the oil of terrestrial agricultural plants. Calculations of the threshold value of the content of eicosapentaenoic and docosahexaenoic acids in feed for salmon fish (Salmonidae) with partial replacement of fish oil with vegetable oil are presented. Another possible way to transform aquaculture into a producer of polyunsaturated fatty acids is to partially replace fishmeal in feed with flour from terrestrial invertebrates. Some species of insects and worms that are promising for aquaculture as objects for the production of feed meal are considered.

Aquaculture is the future bridging gap for the declining capture fisheries and currently the fish cage culture in Lake Victoria (Kenya) is on the increase according to the recent overview surveys of 2016-2017. To date, the majority of aquaculture practices have had few adverse effects on ecosystems. However, due to the potential positive and negative impacts, there are varied opinions on the actual social impacts and threats on the lake ecosystem. The fisher community perspectives on the nascent and growing technology on culture of Nile tilapia since it’s onset in 2005 were assessed using 4 selected sites. Both structured questionnaire and socio-economic activities along the fish landing beaches on Lake Victoria, Kenya were used, based on the presence of beach management units (BMUs), fishing and potential for cage activities; to assess the respondent’s perception on and attitudes towards new fish cage culture method. Few people are involved in cage culture activities, being a relatively new technology. Results from 78 randomly selected respondents from 4 sites of Ngore, Ragwe, Sindo and Nyandiwa beaches showed that fishing and fish trading were the main types of occupation. All the respondents have used and benefited from fish and fishery products for between 1 and 46 years, with a mean of 11 (±8) years. Among the notable positive impacts includes creation of employment opportunities throughout the fish value chain; and development of new and improved rural infrastructure, and road networks along the lake coastal zones. Potential impacts and advantages of cage farming over other fish culture methods are highlighted. From the preliminary socioeconomic surveys data and distribution of cages, valuable measures that management agencies should consider are outlined to support sustainable investment and development of cage culture in Lake Victoria.

Indicators of the condition factor, growth rate, and quality of the final products of cultivated objects are important parameters for the effective management of cold-water fish farming. These indicators are also used as a way to control the impact of environmental factors on fish, which requires constant research in the context of intensification of the aquaculture sector. The research is aimed at determining the condition factor and the amino acid composition of muscle tissues of Salmo trutta fario (Linnaeus, 1758), Oncorhynchus mykiss (Walbaum, 1792), and Salvelinus fontinalis (Mitchill, 1814) under the conditions of the western region of Ukraine. The results of the condition factor showed that S. fontinalis had the highest value with 1.52±0.0340, and O. mykiss and S. trutta showed the lowest value with 1.33±0.0361 and 1.26±0.0181, respectively. Food conversion ratios were similar for S. fontinalis and O. mykiss (1.0), whereas S. trutta showed higher values (1.4). The specific growth rate was highest in rainbow trout. The specific growth rate was higher for rainbow trout (1.4) compared to the brook trout (1.32) and brown trout (1.28). The maximum content of protein, total amino acids (TAA), total essential amino acids (TEAA) and nonessential amino acids (TNEAA) we registered in brook trout. The muscle tissue of the investigated fish species is a well-balanced source of the nutrition energy in terms of the ratio of total essential to total nonessential amino acids (TEAA:TNEAA ratio).

The present research was planned to assess the harmful effects of heavy metals as well as antioxidant alterations of Oreochromis niloticus collected from two polluted fish farms located in Abbassa and Manzala (areas A and B, respectively) in Egypt. They were compared with reference site in central laboratory for aquaculture researchers during the summer season, 2020. A total number of 75 fish collected from all sites was subjected to clinical, postmortem, and bacteriological examination. Water parameters, as well as heavy metals (arsenic, manganese, and nickel) in water, serum, and tissues (muscle, gills, and liver), were evaluated. In addition, antioxidant enzymes (SOD and CAT) and (MDA) were assessed in the serum of O. niloticus. Bacterial isolates, Aeromonas hydrophila, were identified in fish at both localities, and the recorded mortality rate was about 30% and 5% in areas A and B, respectively. The levels of As in water samples from both polluted areas were higher than the permissible limits. In addition, serum of O. niloticus showed a significant decrease in the concentrations of Ni in both polluted areas. In addition, a significant decrease in the mean levels of Ni and As was found in the gills and muscles of O. niloticus in both polluted areas. Moreover, a significant decrease in CAT, combined with a significant increase of SOD activities was observed in polluted area A.

The article presents the resource base of the internal reservoirs of the Russian Federation. The relevance of recreation in Russia is considered. The risks inherent in this area are presented. There are organizations that provide a range of services to people who are passionate about fishing. The advantages of opening a fish reservoir for fishing are considered. The project of organizing a recreation area on the territory of the agricultural center is calculated. Performance indicators of the service provided are presented.

The aquaculture industry's rapid growth to meet commercial demand can trigger an outbreak of infectious diseases due to high-density farming. Antibiotic overuse and misuse in fish farming and its global health consequences have led to searching for more natural alternatives such as medicinal plants. In this sense, garlic (Allium sativum) has different bioactive compounds with biological properties for animal health. Among them are the ajoene, alliin, and allicin, which confer biological properties such as growth promotion, antimicrobial, antiviral, antioxidant, and antiparasitic. Ways to use garlic in aquaculture include oil, fresh mash, aqueous extract, and garlic powder. The powder presentation is the most used in aquaculture; it is generally applied by oral administration, adding to the feed, and the dose used ranges from 0.05 to 40 g/kg of feed. Garlic has been used in the aquaculture of different species such as rainbow trout (Oncorhynchus mykiss), spotted grouper (Epinephelus coioides), catfish (Clarias gariepinus), tilapia (Oreochromis niloticus), guppy fish (Poecilia reticulata), goldfish (Carassius auratus), and barramundi (Lates calcarifer). In addition to its properties, garlic's usage became popular, thanks to its low cost, easy incorporation into food, and little environmental impact. Therefore, its application can be an effective solution to combat diseases, improve organisms' health using natural supplies, and as an alternative to antibiotics. This review reports and discusses plant-derived products' beneficial properties, emphasizing garlic and its usages in fish aquaculture.

Some common practices in aquaculture, ornamental trade and fish facilities may disturb the behavioural repertoire of fish and its natural adaptive value, reducing welfare and impairing fish production. Hence, it is necessary to understand fish behaviour, as well as the factors affecting it, to improve the quality of fish's life under artificial environment. Here, we reviewed the behaviour of the angelfish Pterophyllum scalare, an Amazonian cichlid used worldwide both as an ornamental fish and as a fish model in scientific research. We characterized social, reproductive and feeding behaviour, as well as the amazing cognitive ability of the angelfish. In addition, we reviewed the effects of environmental enrichment and suggested some important variables that need to be considered for rearing P. scalare. In this review, we show for the first time a synthesis on behaviour and a best practice overview to improve the welfare of angelfish as a target species. Nonetheless, most topics reviewed fit a broader set of fish species, particularly ornamental ones. This synthesis can therefore open a path for further behavioural research applied to the welfare of angelfish and bring insights to other fish species.

Nursery needs to be developed to strengthen the grouper as a superior commodity for the Seribu Islands Administrative District, Jakarta. This effort is carried out through the development of human resources (HR) and appropriate technology (AT), and hoped that the grouper nursery will become a new business unit in this district, where most of the area is sea. This activity aims to develop HR and AT for grouper nursery through training, piloting, and mentoring. This activity was carried out to 23 community members who are members of the three fish farmer groups. The training materials including the technical and management aspects of the grouper nursery. The piloting and mentoring of grouper nursery were carried out in parallel with the development of AT in the form of the application of garlic-meniran flour, and were carried out at the Sea Farming Center of PKSPL-IPB, Seribu Islands. The piloting includes preparing of cages, stocking of seeds, feeding, water quality and fish health management, sampling, harvesting, and post-harvest handling. The mentoring is carried out by serving participant visits to the center, interviews and meetings. After the training there was an increase in knowledge and skills of the participants, as well as the emergence of motivation to start a grouper nursery business. During the piloting and mentoring, the involvement and enthusiasm of the participants was relatively high and various aspects were discussed. The application of meniran-garlic flour in feeding on grouper nurseries can improve the feed conversion ratio, so that feed costs are more efficient. One of the participants has tried to run humpback grouper fish farming independently, and made a profit after two months of rearing.

The addition of natural reproduction of hydrobionts by the fish farming to provide a fishery resources and preserve the biological diversity of water ecosystems. Fish farming based on scientific recommendations in Russia according to federal legislation. The need to develop scientific recommendations has been related to the fact conditions of each water body determine the number of fish juveniles that can be provided with conditions for their growth. Currently, the term "maximum permissible volumes of release" (PDOV) used in regulatory documents governing the development of recommendations for fish farming. At the same time, the definition of this term is not given in the legislation, which implies its interpretation. The lack of explicit wording of the term makes it possible to use a variety of approaches and methods in the preparation of recommendations. Аs expected, the use of different methods gives different results. There is debate about the eligibility of applying different approaches when discussing the results, since each expert has a different view on the problem of determining the maximum permissible number for release. This situation indicates the need to approve unified methodological approaches to assessing the maximum permissible number of fish juveniles to release. It is necessary to supplement governing document with provisions in which, based on the availability and quality of available information on the reproduction conditions and the feed base of juvenile fish, existing methodological approaches to determining the maximum permissible number for release, various levels of information support can be distinguished to substantiate the maximum permissible number of fish juveniles.

Branch of Muhammadiyah Tegalboto Kidul is a forum for Muhammadiyah da'wah activities within the scope of the village level. Muhammadiyah's space for movement is not only in religious activities, but in social, economic and other fields. The activity program of the Muhammadiyah branch of Tegal Boto Kidul which has been running so far is only in the routine study of recitation and social movements such as compensation for the needy. Activities related to economic development in branch members in particular and the surrounding community have generally not been carried out much. The purpose of this community service is to provide education to the community as a solution to limited land owned but still able to carry out fish farming and vegetable and fruit farming activities. This service aims to optimize the narrow land with a fish farming system in small media, does not require large areas, is cheap, is easily available media and technology that can be carried out by all groups of society at large. This service is expected to be a solution to the problem of limited land for fish cultivation, especially in cities, the problem of decreasing the availability of aquaculture and the problem of the need for fish animal protein in the community. The implementation of this community activity has been carried out during pandemic Covid-19 in Tegalboto Village, Sumbersari District, Jember Regency, including counseling, education and training on “budidakmber”, measuring the quality of cultivated water, measuring the weight of catfish.