The requirement for high-quality seafood is a global challenge in today’s world due to climate change and natural resource limitations.Internet of Things(IoT)based Modern fish farming systems can significantly optimi...The requirement for high-quality seafood is a global challenge in today’s world due to climate change and natural resource limitations.Internet of Things(IoT)based Modern fish farming systems can significantly optimize seafood production by minimizing resource utilization and improving healthy fish production.This objective requires intensive monitoring,prediction,and control by optimizing leading factors that impact fish growth,including temperature,the potential of hydrogen(pH),water level,and feeding rate.This paper proposes the IoT based predictive optimization approach for efficient control and energy utilization in smart fish farming.The proposed fish farm control mechanism has a predictive optimization to deal with water quality control and efficient energy consumption problems.Fish farm indoor and outdoor values are applied to predict the water quality parameters,whereas a novel objective function is proposed to achieve an optimal fish growth environment based on predicted parameters.Fuzzy logic control is utilized to calculate control parameters for IoT actuators based on predictive optimal water quality parameters by minimizing energy consumption.To evaluate the efficiency of the proposed system,the overall approach has been deployed to the fish tank as a case study,and a number of experiments have been carried out.The results show that the predictive optimization module allowed the water quality parameters to be maintained at the optimal level with nearly 30%of energy efficiency at the maximum actuator control rate compared with other control levels.展开更多
It is not understood well that how the effects of land use and fish farming on the contents of alkali metals (Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</...It is not understood well that how the effects of land use and fish farming on the contents of alkali metals (Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup>) in small water bodies of pond and reservoir ecosystems at the watershed scale. In this study, the concentrations of Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup> in water bodies were measured for 103 ponds and reservoirs used as fish farming or surrounded by different agricultural land use types in the subtropical hilly watershed of Jinjing (105 km<sup>2</sup>), China. The two important environmental factors of fishing farming and agricultural land use influenced the spatial variation the contents of alkali metals. The ponds and reservoirs in residential area had significantly higher concentrations of Ca<sup>2+</sup> and Na<sup>+</sup> than those with other land use types, reflecting the influence of domestic wastewater. Compared with those of natural ponds with non-fish farming, no significant increase of alkali metal contents occurred in fish farming ponds, due to the regular cleaning of ponds by farmers. However, the effect of fish culture on alkali metal contents was still supported indirectly by the fact that the alkali metal contents significantly correlated with nitrate contents in fish farming ponds and but high related with that of DIP in natural ponds. The suitability assessment for irrigation on the pond water indicated that almost all of ponds were suitable for irrigation except some ponds surrounded by residential area and tea plantation. Generally, our results demonstrated that fish farming and agricultural land use affected the contents of alkali metals in ponds and reservoirs. The agricultural water irrigation would be with caution from the ponds with tea plantation and residential area in the subtropical hilly watershed.展开更多
The study was carried out in Matiranga Upazila,Bandarban district,which is considered one of Bangladesh’s major hill tract regions.The study aimed to identify present farming conditions,prospects,and problems and sui...The study was carried out in Matiranga Upazila,Bandarban district,which is considered one of Bangladesh’s major hill tract regions.The study aimed to identify present farming conditions,prospects,and problems and suitable solutions to the problems of fish farming.Different participatory rapid appraisal tools such as focus group discussion,field visits,and farmers’interviews were used to collect relevant fish farming information in the study area.The polyculture method was the most practised aquaculture method.Among the selected farms,eleven fish species were identified as culture species.The transportation cost for seeds purchased from remote areas was high(11%of total seed cost).The average transportation-related mortality of fish fry and fingerlings was 7.2%and 2.8%.Feed cost was found as the major cost(58.4%)in aquaculture.Costs and revenue for fish production per decimal varied from BDT 311 to 3528 and BDT 23 to 1268.Utilization of vacant lake,youth and women engagement,integrated aquaculture,the desire of people to engage in aquaculture,and available human resources were found as significant prospects.The major problems identified were lack of hatchery,high feed cost,lack of stakeholder linkage,lack of capital for fish farming,and lack of proper knowledge,guidelines,and consultancy for fish culture.A community-based aquaculture model was proposed to overcome the present challenges and problems in the study area.The model may help to expand aquaculture and thus improve the livelihood and socio-economic status of the people of the hilly areas of Bangladesh.展开更多
This study aims to evaluate and compare the fertilizing effects of fish-breeding water and river water combined or not with composted poultry manure on the growth and production of okra and lettuce crops. Thus, a samp...This study aims to evaluate and compare the fertilizing effects of fish-breeding water and river water combined or not with composted poultry manure on the growth and production of okra and lettuce crops. Thus, a sample of 2000 Nile tilapia Oreochromis niloticus fry and a sample of 100 Cobb 500 strain chicks were reared and monitored for six months and fifteen days. Poultry manure and fish-breeding water were then collected and used to fertilize and water okra and lettuce crops. Two systems were used for the crops (okra and lettuce) tested in an elementary plot design with replicates for each treatment (T1: fish-breeding water alone;T2: river water alone;T3: fish-breeding water combined with manure;T4: river water combined with manure). Morphometric parameters and phenological traits of okra and lettuce crops as well as the total harvest weight and production yield were evaluated and compared between treatments. The results reveal better growth and higher yields (0.67 kg/m<sup>2</sup> vs. 0.45 kg/m<sup>2</sup>) of okra crops that received treatment T1 compared to T2. The best growth and yields of lettuce were obtained with treatments T3 (3.34 kg/m<sup>2</sup>) and T1 (1.89 kg/m<sup>2</sup>) compared to T4 (1.23 kg/m<sup>2</sup>) and T2 (1.20 kg/m<sup>2</sup>). These results show that fish-breeding water combined with poultry manure can boost okra and lettuce production and would be a real asset to stimulate local agricultural development. Thus, the adoption of such an agro-ecological approach integrating fish farming and animal husbandry could increase local production and provide food of good nutritional quality.展开更多
Inland fishing predominates in the Kedougou region, which has no coastline. This type of fishing does not yet meet the local population’s demand for fish products. In response to this concern, a Community Agricultura...Inland fishing predominates in the Kedougou region, which has no coastline. This type of fishing does not yet meet the local population’s demand for fish products. In response to this concern, a Community Agricultural Estate housing an integrated fish farm was set up in the commune of Bandafassi, in the village of Itato. Since its creation, this production unit has been faced with the problem of sourcing high-quality, low-cost, monosex male Oreochromis niloticus fry. In order to overcome this constraint, the present research focuses on the contribution of Garcinia kola to the productivity and economic profitability of the Itato farm. The aim of the research is to assess fish production in the experimental set-up and the production costs of tilapia in a controlled environment. The comparative study of the various production factors shows disparities only in the input factor, where scenarios 2 and 3 use additional products. These are 17-α-methytestosterone for scenario 2 and Garcinia kola for scenario 3. These products significantly interfere with fish production, with a fairly high mortality rate for scenario 2 (25% for two production cycles/ cohort2 (B5, B6, B7 and B8) treated with 17-α-methytestosterone). As for scenarios 1 and 3, mortalities are 5% with or without recourse to additional products (G. kola). In addition, average fish production for the three (03) scenarios is estimated at 28687.5 kg/2 cycles. It varies from one scenario to another, i.e. 30937.5 kg/2 cycles for scenarios 1 and 3 and 24187.5 kg/2 cycles for scenario 2. It is therefore higher in scenarios 1 and 3 than in scenario 2. This difference is due to the fairly large losses of individuals in scenario 2. Furthermore, the analysis of the profit and loss accounts for tilapia production varies from one scenario to another depending on the type of farm: 476 Franc CFA for scenario 1, 610 Franc CFA for scenario 2 and 472 Franc CFA for scenario 3 (F CFA = franc of the French Colonies of Africa). The Average operating income for all the fish farming units is 34,726,142 Franc CFA. The highest (41,638,075 Franc CFA) and lowest (29,281,075 Franc CFA) ERs were observed in scenarios 3 and 2 respectively. It was 33,259,275 Franc CFA for scenario 1. The difference between the NERs of the three scenarios is more or less significant in terms of results. The operating result (OR) is positive in all 3 scenarios in our study. However, the scenario 3 system generates a higher rate of return (the ratio between an income and the capital employed to obtain that income) (74%) than that generated by the scenario 1 system (69%). As for the scenario 2 system, it generates a lower financial return than the two previous systems (67%). Above all, this work made it possible to construct an approach that would make it possible to answer such a question by relying successively on various methods: a typology, according to the production factors involved in the operation of the Community Agricultural Estate fish farm.展开更多
Peri-urban fish farms with limited access to open natural water bodies draw fresh water from urban water supply and dug wells,which is unreliable and costly.Reuse of fish pond effluent is also limited by high ammonia ...Peri-urban fish farms with limited access to open natural water bodies draw fresh water from urban water supply and dug wells,which is unreliable and costly.Reuse of fish pond effluent is also limited by high ammonia concentration(>0.3 mg/L)that renders water toxic and is stressful to fish.Despite the existence of several fish effluent treatment methods,not all may be appropriate for a particular location.This review article therefore examines the various fish effluent treatment methods to aid selection of the most suitable one(s)for peri-urban areas.The key parameters considered in their comparison were:initial,operational and maintenance costs;ammonia removal efficiency;energy consumption and land requirement.The effluent treatment methods are both conventional and non-conventional.Despite a slight higher treatment efficiency and less space requirement by conventional methods,they mainly require reliable power supply for continuous running,highly skilled labor for operation and maintenance leading to high operational costs.In addition,their investment costs are higher than non-conventional methods,hence not widely applied in developing countries and majority have broken down.On the other hand,non-conventional methods such as constructed wetlands are widely in use for treating effluent mainly due to their cost effectiveness and no or little energy requirement.Constructed wetlands were found most suitable bio-filtration system for treating fish effluent because they are cost effective,require less skilled labor and still have better effluent treatment though space required is slightly more.Vegetables(lettuce,collards,etc.)have potential to grow in constructed wetlands thus form vegetable-based bio-filtration units which serve not only as bio-filters but also provide additional sources of nutrition and income.This review indicated limited information on the appropriate size and performance of vegetable-based bio-filtration unit utilizing indigenous vegetables and recommended further research to explore the idea.展开更多
In captive conditions, most neotropical migratory species do not have the necessary incentive to complete gonadal maturation and spawning, which require induction techniques, usually with the use of hormones. Numerous...In captive conditions, most neotropical migratory species do not have the necessary incentive to complete gonadal maturation and spawning, which require induction techniques, usually with the use of hormones. Numerous studies have therefore focused on finding an effective hormonal treatment to induce reproduction for each species. A standard treatment was successfully developed for most of these species, which consists of two doses of Carp Pituitary Extract (CPE), totaling 5.5 mgCPE/kg of fish. However, the best strategy for the subsequent fertilization of gametes is still unclear. This study was conducted with five species of commercial interest that do not reproduce naturally in captivity: pacu Piaractus mesopotamicus, piracanjuba Brycon orbignyanus, curimbatá Prochilodus lineatus, dourado Salminus brasiliensis and piau?u Leporinus macrocephalus. Ninety-nine broodstocks were used, consisting of males and females of the five species to compare two techniques for spawning and fertilization: extrusion followed by the dry method and natural spawning. All fish were induced with two hormone doses, i.e., 0.5 and 5.0 mgCPE/kg, and were subjected to one of the two types of fertilization. The results were compared using the fertilization rate, number of oocytes produced, relative fecundity and the broodstocks' survival rate on days following spawning. All species responded positively to spawning for extrusion, and only S. brasiliensis did not spawn through the natural spawning method. The natural spawning technique provided a higher fertilization rate of eggs and a greater broodstock survival rate (P S. brasiliensis. It was concluded that the natural spawning technique can increase the production of viable eggs and reduce the mortality of species during breeding, except for S. brasiliensis.展开更多
Since amateur fishing in fishponds has been on the increase in Brazil, there is a great concern on the microbiological quality of fish. One hundred and thirty-eight samples were collected during the dry and rainy peri...Since amateur fishing in fishponds has been on the increase in Brazil, there is a great concern on the microbiological quality of fish. One hundred and thirty-eight samples were collected during the dry and rainy periods in ten fish farms. Aeromonas spp. counts and tests for sensitiveness to antimicrobials were performed, coupled to the physical and chemical analyses of water. Tests revealed that 70% of samples were contaminated by Aeromonas spp., with water averaging 2.92 Log CFU/100 mL during the rainy period and 3.16 Log CFU/100 mL during the dry one. Fish contaminated by Aeromonas spp. averaged 2.58 Log CFU/100 mL during the rainy period and 3.53 Log CFU/100 mL during the dry one. Aeromonas spp. samples were multi-resistant to 2 or 8 antimicrobials in 62.5% of the samples. Ampicillin was the antimicrobial with the highest resistance percentage rate. Results showed that fish bred in amateur fish farms constituted a health risk for the population.展开更多
This study focuses on the analysis of seasonal dynamics of physicochemical parameters(pH and Eh)and organic matter content in the sediments accumulated within the impact zone of the cage trout farm(Lake Ladoga,Russia)...This study focuses on the analysis of seasonal dynamics of physicochemical parameters(pH and Eh)and organic matter content in the sediments accumulated within the impact zone of the cage trout farm(Lake Ladoga,Russia).The Ladoga is the largest lake in Europe and there are more than 20 fish farms located in the northern part of the waterbody.The geochemical research is necessary for predicting the negative impact of the polluted sediments on both the cage fish and the aquatic ecosystem.The sampling was conducted during various seasons of the year(February,June,August,October)which were characterized by the different fish feeding regimes.The sediment cores were collected at 7 points,including the cage and reference sites(150 m and 600 m far from the farm).The results showed that the accumulation of organic material released from the studied fish farms was local and the wastes did not enter the sediments at the control sites.Furthermore,the accumulated organic layer can be compacted and partially mineralized during winter period.Nevertheless,strongly reducing conditions in sediments occur due to the accumulation of organic material and low rate of water exchange within the studied bay.Therefore,there is a potential risk of formation of toxic gases and release of accumulated nutrients and metals from sediments to water.It can have a negative impact on benthic and nekton organisms,in particular cage fish.展开更多
Ecological stoichiometry of nitrogen and phosphorus is an important indicator to characterize the nitrogen and phosphorus trophic status in aquatic ecosystems. The study of the spatio-temporal patterns of nitrogen and...Ecological stoichiometry of nitrogen and phosphorus is an important indicator to characterize the nitrogen and phosphorus trophic status in aquatic ecosystems. The study of the spatio-temporal patterns of nitrogen and phosphorus stoichiometry is beneficial to the nitrogen and phosphorus pollution management in pond ecosystems. In this study, 18 groups (36 in total) of typical cascade ponds were selected as long-term observations to investigate the spatial distribution patterns of nitrogen and phosphorus component ratios (ratio of total nitrogen to phosphorus: TN:TP, ratio of dissolved nitrogen to phosphorus: TDN:TDP, ratio of particulate nitrogen to phosphorus: PN:PP) in water bodies in the tropical agricultural watershed of Jinjing. The results showed that the average values of TN:TP and TDN:TDP in the upstream ponds were 26.4 and 53.4, respectively, and were more than those in the downstream (22.95 and 48.1, respectively). In contrast, the PN:PP (13.78) in the upstream was significantly lower than that of the downstream (30.39). Furthermore, the factors of rainfall, agricultural land use and fish farming influenced the spatio-temporal variability of the N:P ratios. The ratios of TN:TP and TDN:TDP were higher in the wet season and lower in the dry season. Agricultural land use and fish farming reduced the ratios of the above three nitrogen and phosphorus components in cascade ponds in the study area. Our results show that strengthening agricultural land pollution control and aquaculture management could help to improve water quality of pond ecosystems in the study area.展开更多
In this paper,we analyze the dynamical behavior of fish farm model related to Atangana-Baleanu derivative of arbitrary order.The rnodel is constituted with the group of non-linear differential equations having nutrien...In this paper,we analyze the dynamical behavior of fish farm model related to Atangana-Baleanu derivative of arbitrary order.The rnodel is constituted with the group of non-linear differential equations having nutrients,fish and mussel.We have included discrete kind gestational delay of fish.The solution of fish farm model is determined by employing homotopy analysis transforms method(HATM).Existence of and uniqueness of solution are studied through Picard-Lindelof approach.The influence of order of new non-integer order derivative on nutrients,fish and mussel is discussed.The complete study reveals that the outer food supplies manage the behavior of the model.Moreover,to show the outcomes of the study,some numerical results are demonstrated through graphs.展开更多
Aquaculture provides significant contributions to household food security,as the capture of wild fish from lakes,dams,and oceans do not meet the current demand for animal protein in Tanzania.Sustainable aquaculture re...Aquaculture provides significant contributions to household food security,as the capture of wild fish from lakes,dams,and oceans do not meet the current demand for animal protein in Tanzania.Sustainable aquaculture requires well-established regulatory systems and extension services for good pond management practices and maintaining fish health by fish farmers.Fish farming is practiced widely in Tanzania,from small-to large-scale ponds and these farming systems are moving from extensive normal operations(low input demand)to intensive farming(high input demand).However,the industry is largely still operating at a subsistence level with low production.Bacterial infections have been occurring in these fish farms and will continue to be an issue of concern into the future.This review highlights the current challenges,successes,and prospects towards a sustainable aquaculture industry in Tanzania,including:limited extension services mirroring the limited knowledge by farmers regarding pond management practices;the inadequacy of funds to carry out fish disease research or implement a surveillance system;little expertise in fish disease diagnosis and treatment;and poor management options.To minimize disease outbreaks and optimize production in the future,we suggest a strengthening of extension services,augmented with on-farm knowledge transfer.Emphasis should be on pond management practices and fish disease management;the creation of a well-functioning fish disease surveillance system;and strengthening collaborative research on aquaculture between the government research institutions and academia.Establishing small cooperative fish farmer groups within the Aquaculture Association of Tanzania(AAT)for easy access to information is also recommended.展开更多
In Amazonia,small-oriented family businesses or communities cultivate freshwater organisms as a source of income.Although effective management is fundamental for optimizing cultivated stocks,Amazonian aquaculture beli...In Amazonia,small-oriented family businesses or communities cultivate freshwater organisms as a source of income.Although effective management is fundamental for optimizing cultivated stocks,Amazonian aquaculture belittles the importance of genetic diversity,relying primarily on phenotypical characteristics during breeders’selection.To provide a“proof of concept”built on the premise that implementing modern technologies is crucial to optimizing fish stocks in rural Amazonian fish farms,we conducted a pilot study assessing genetic diversity on cultivated Piaractus brachypomus from Caquet´a,Colombia.We used mitochondrial control region(CR)sequences to evaluate heterogeneity.Our data revealed low genetic diversity and suggested that most sampled individuals probably originated from a single maternal lineage.Haplotype diversification resulted from discrete point mutations not associated with geographical location.Polymorphisms accumulate in non-conserved CR regions,yet the most divergent haplotypes display mutations in conserved CR sequences with roles in mitochondrial metabolisms and proliferation.Overall,our results indicate a need in the local industry to design breeding strategies to enhance diversity to avoid deleterious effects caused by inbreeding and domestication.展开更多
The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production a...The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production and developmental sectors.However,intensification demands increased inputs,such as fish and feed per unit culture area and,therefore,increased waste generation from the aquaculture production systems.The impact of waste products from aquaculture has increased public concern and threatens the sustainability of aquaculture practices.The need for increasing the production of aquaculture products cannot be overemphasized and,therefore,there is a need to develop culture systems that will increase fish production with efficient waste management in order to limit environmental degradation resulting from aquaculture wastes and ensure its sustainability.This paper reviewed various aspects of waste production from aquaculture,their sources,components,and methods of management,in different culture systems,primarily discussing waste production from feed,chemicals,and pathogens.We aimed to establish the sources of wastes,their contents,and potential harms to both the fish culture and the environment.Suggestions for managing wastes in different culture systems were made to ensure an improved and sustainable aquaculture production.展开更多
Objective:To determine the prevalence,mean intensity,and abundance of monogenean parasites in Clarias gariepinus(C.gariepinus)from two selected fish farms in Calabar,Cross River State,Nigeria.Methods:Eighty specimens ...Objective:To determine the prevalence,mean intensity,and abundance of monogenean parasites in Clarias gariepinus(C.gariepinus)from two selected fish farms in Calabar,Cross River State,Nigeria.Methods:Eighty specimens of C.gariepinus from the two farms(40 each)were necropsied for parasitological analysis.Skin,gill and fin biopsies were prepared from each specimen following standard methods for microscopic analysis.Parasitological indices including dominance(D),prevalence,mean intensity and abundance were calculated according to standard formulae.Data were analyzed using the Fisher's exact test.Results:C.gariepinus from the two farms were infested with a total of ninety individuals of monogenean parasites belonging to three species including Macrogyrodactylus clarii(M.clarii),Gyrodactylus sp.and Dactylogyrus sp.D index showed that the three monogenean species were eudominant(D-value>10%).Gyrodactylus sp.was more abundant(46)followed by Dactylogyrus sp.(23)while M.clarii was the lowest(21).Prevalence,meaning intensity and abundance of monogenean parasites in the two farms,varied insignificantly higher(P>0.05).Prevalence in both farms were higher in female C.gariepinus than that in male.Monogenean parasites exhibited organ specificity as M.clarii and Dactylogyrus sp.were recovered from the gills while Gyrodactylus sp.colonized the skin and fin.Conclusions:High abundance of these parasites may lead to poor growth performance and high mortality in C.gariepinus,leading to huge monetary loss and low profit margin by increasing production cost due to the cost of treatments.展开更多
基金funded by the Ministry of Science,ICT CMC,202327(2019M3F2A1073387)this work was supported by the Institute for Information&communications Technology Promotion(IITP)(NO.2022-0-00980,Cooperative Intelligence Framework of Scene Perception for Autonomous IoT Device).
文摘The requirement for high-quality seafood is a global challenge in today’s world due to climate change and natural resource limitations.Internet of Things(IoT)based Modern fish farming systems can significantly optimize seafood production by minimizing resource utilization and improving healthy fish production.This objective requires intensive monitoring,prediction,and control by optimizing leading factors that impact fish growth,including temperature,the potential of hydrogen(pH),water level,and feeding rate.This paper proposes the IoT based predictive optimization approach for efficient control and energy utilization in smart fish farming.The proposed fish farm control mechanism has a predictive optimization to deal with water quality control and efficient energy consumption problems.Fish farm indoor and outdoor values are applied to predict the water quality parameters,whereas a novel objective function is proposed to achieve an optimal fish growth environment based on predicted parameters.Fuzzy logic control is utilized to calculate control parameters for IoT actuators based on predictive optimal water quality parameters by minimizing energy consumption.To evaluate the efficiency of the proposed system,the overall approach has been deployed to the fish tank as a case study,and a number of experiments have been carried out.The results show that the predictive optimization module allowed the water quality parameters to be maintained at the optimal level with nearly 30%of energy efficiency at the maximum actuator control rate compared with other control levels.
文摘It is not understood well that how the effects of land use and fish farming on the contents of alkali metals (Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup>) in small water bodies of pond and reservoir ecosystems at the watershed scale. In this study, the concentrations of Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup> in water bodies were measured for 103 ponds and reservoirs used as fish farming or surrounded by different agricultural land use types in the subtropical hilly watershed of Jinjing (105 km<sup>2</sup>), China. The two important environmental factors of fishing farming and agricultural land use influenced the spatial variation the contents of alkali metals. The ponds and reservoirs in residential area had significantly higher concentrations of Ca<sup>2+</sup> and Na<sup>+</sup> than those with other land use types, reflecting the influence of domestic wastewater. Compared with those of natural ponds with non-fish farming, no significant increase of alkali metal contents occurred in fish farming ponds, due to the regular cleaning of ponds by farmers. However, the effect of fish culture on alkali metal contents was still supported indirectly by the fact that the alkali metal contents significantly correlated with nitrate contents in fish farming ponds and but high related with that of DIP in natural ponds. The suitability assessment for irrigation on the pond water indicated that almost all of ponds were suitable for irrigation except some ponds surrounded by residential area and tea plantation. Generally, our results demonstrated that fish farming and agricultural land use affected the contents of alkali metals in ponds and reservoirs. The agricultural water irrigation would be with caution from the ponds with tea plantation and residential area in the subtropical hilly watershed.
文摘The study was carried out in Matiranga Upazila,Bandarban district,which is considered one of Bangladesh’s major hill tract regions.The study aimed to identify present farming conditions,prospects,and problems and suitable solutions to the problems of fish farming.Different participatory rapid appraisal tools such as focus group discussion,field visits,and farmers’interviews were used to collect relevant fish farming information in the study area.The polyculture method was the most practised aquaculture method.Among the selected farms,eleven fish species were identified as culture species.The transportation cost for seeds purchased from remote areas was high(11%of total seed cost).The average transportation-related mortality of fish fry and fingerlings was 7.2%and 2.8%.Feed cost was found as the major cost(58.4%)in aquaculture.Costs and revenue for fish production per decimal varied from BDT 311 to 3528 and BDT 23 to 1268.Utilization of vacant lake,youth and women engagement,integrated aquaculture,the desire of people to engage in aquaculture,and available human resources were found as significant prospects.The major problems identified were lack of hatchery,high feed cost,lack of stakeholder linkage,lack of capital for fish farming,and lack of proper knowledge,guidelines,and consultancy for fish culture.A community-based aquaculture model was proposed to overcome the present challenges and problems in the study area.The model may help to expand aquaculture and thus improve the livelihood and socio-economic status of the people of the hilly areas of Bangladesh.
文摘This study aims to evaluate and compare the fertilizing effects of fish-breeding water and river water combined or not with composted poultry manure on the growth and production of okra and lettuce crops. Thus, a sample of 2000 Nile tilapia Oreochromis niloticus fry and a sample of 100 Cobb 500 strain chicks were reared and monitored for six months and fifteen days. Poultry manure and fish-breeding water were then collected and used to fertilize and water okra and lettuce crops. Two systems were used for the crops (okra and lettuce) tested in an elementary plot design with replicates for each treatment (T1: fish-breeding water alone;T2: river water alone;T3: fish-breeding water combined with manure;T4: river water combined with manure). Morphometric parameters and phenological traits of okra and lettuce crops as well as the total harvest weight and production yield were evaluated and compared between treatments. The results reveal better growth and higher yields (0.67 kg/m<sup>2</sup> vs. 0.45 kg/m<sup>2</sup>) of okra crops that received treatment T1 compared to T2. The best growth and yields of lettuce were obtained with treatments T3 (3.34 kg/m<sup>2</sup>) and T1 (1.89 kg/m<sup>2</sup>) compared to T4 (1.23 kg/m<sup>2</sup>) and T2 (1.20 kg/m<sup>2</sup>). These results show that fish-breeding water combined with poultry manure can boost okra and lettuce production and would be a real asset to stimulate local agricultural development. Thus, the adoption of such an agro-ecological approach integrating fish farming and animal husbandry could increase local production and provide food of good nutritional quality.
文摘Inland fishing predominates in the Kedougou region, which has no coastline. This type of fishing does not yet meet the local population’s demand for fish products. In response to this concern, a Community Agricultural Estate housing an integrated fish farm was set up in the commune of Bandafassi, in the village of Itato. Since its creation, this production unit has been faced with the problem of sourcing high-quality, low-cost, monosex male Oreochromis niloticus fry. In order to overcome this constraint, the present research focuses on the contribution of Garcinia kola to the productivity and economic profitability of the Itato farm. The aim of the research is to assess fish production in the experimental set-up and the production costs of tilapia in a controlled environment. The comparative study of the various production factors shows disparities only in the input factor, where scenarios 2 and 3 use additional products. These are 17-α-methytestosterone for scenario 2 and Garcinia kola for scenario 3. These products significantly interfere with fish production, with a fairly high mortality rate for scenario 2 (25% for two production cycles/ cohort2 (B5, B6, B7 and B8) treated with 17-α-methytestosterone). As for scenarios 1 and 3, mortalities are 5% with or without recourse to additional products (G. kola). In addition, average fish production for the three (03) scenarios is estimated at 28687.5 kg/2 cycles. It varies from one scenario to another, i.e. 30937.5 kg/2 cycles for scenarios 1 and 3 and 24187.5 kg/2 cycles for scenario 2. It is therefore higher in scenarios 1 and 3 than in scenario 2. This difference is due to the fairly large losses of individuals in scenario 2. Furthermore, the analysis of the profit and loss accounts for tilapia production varies from one scenario to another depending on the type of farm: 476 Franc CFA for scenario 1, 610 Franc CFA for scenario 2 and 472 Franc CFA for scenario 3 (F CFA = franc of the French Colonies of Africa). The Average operating income for all the fish farming units is 34,726,142 Franc CFA. The highest (41,638,075 Franc CFA) and lowest (29,281,075 Franc CFA) ERs were observed in scenarios 3 and 2 respectively. It was 33,259,275 Franc CFA for scenario 1. The difference between the NERs of the three scenarios is more or less significant in terms of results. The operating result (OR) is positive in all 3 scenarios in our study. However, the scenario 3 system generates a higher rate of return (the ratio between an income and the capital employed to obtain that income) (74%) than that generated by the scenario 1 system (69%). As for the scenario 2 system, it generates a lower financial return than the two previous systems (67%). Above all, this work made it possible to construct an approach that would make it possible to answer such a question by relying successively on various methods: a typology, according to the production factors involved in the operation of the Community Agricultural Estate fish farm.
文摘Peri-urban fish farms with limited access to open natural water bodies draw fresh water from urban water supply and dug wells,which is unreliable and costly.Reuse of fish pond effluent is also limited by high ammonia concentration(>0.3 mg/L)that renders water toxic and is stressful to fish.Despite the existence of several fish effluent treatment methods,not all may be appropriate for a particular location.This review article therefore examines the various fish effluent treatment methods to aid selection of the most suitable one(s)for peri-urban areas.The key parameters considered in their comparison were:initial,operational and maintenance costs;ammonia removal efficiency;energy consumption and land requirement.The effluent treatment methods are both conventional and non-conventional.Despite a slight higher treatment efficiency and less space requirement by conventional methods,they mainly require reliable power supply for continuous running,highly skilled labor for operation and maintenance leading to high operational costs.In addition,their investment costs are higher than non-conventional methods,hence not widely applied in developing countries and majority have broken down.On the other hand,non-conventional methods such as constructed wetlands are widely in use for treating effluent mainly due to their cost effectiveness and no or little energy requirement.Constructed wetlands were found most suitable bio-filtration system for treating fish effluent because they are cost effective,require less skilled labor and still have better effluent treatment though space required is slightly more.Vegetables(lettuce,collards,etc.)have potential to grow in constructed wetlands thus form vegetable-based bio-filtration units which serve not only as bio-filters but also provide additional sources of nutrition and income.This review indicated limited information on the appropriate size and performance of vegetable-based bio-filtration unit utilizing indigenous vegetables and recommended further research to explore the idea.
文摘In captive conditions, most neotropical migratory species do not have the necessary incentive to complete gonadal maturation and spawning, which require induction techniques, usually with the use of hormones. Numerous studies have therefore focused on finding an effective hormonal treatment to induce reproduction for each species. A standard treatment was successfully developed for most of these species, which consists of two doses of Carp Pituitary Extract (CPE), totaling 5.5 mgCPE/kg of fish. However, the best strategy for the subsequent fertilization of gametes is still unclear. This study was conducted with five species of commercial interest that do not reproduce naturally in captivity: pacu Piaractus mesopotamicus, piracanjuba Brycon orbignyanus, curimbatá Prochilodus lineatus, dourado Salminus brasiliensis and piau?u Leporinus macrocephalus. Ninety-nine broodstocks were used, consisting of males and females of the five species to compare two techniques for spawning and fertilization: extrusion followed by the dry method and natural spawning. All fish were induced with two hormone doses, i.e., 0.5 and 5.0 mgCPE/kg, and were subjected to one of the two types of fertilization. The results were compared using the fertilization rate, number of oocytes produced, relative fecundity and the broodstocks' survival rate on days following spawning. All species responded positively to spawning for extrusion, and only S. brasiliensis did not spawn through the natural spawning method. The natural spawning technique provided a higher fertilization rate of eggs and a greater broodstock survival rate (P S. brasiliensis. It was concluded that the natural spawning technique can increase the production of viable eggs and reduce the mortality of species during breeding, except for S. brasiliensis.
基金thank CAPES for the award of scholarship to the auhor
文摘Since amateur fishing in fishponds has been on the increase in Brazil, there is a great concern on the microbiological quality of fish. One hundred and thirty-eight samples were collected during the dry and rainy periods in ten fish farms. Aeromonas spp. counts and tests for sensitiveness to antimicrobials were performed, coupled to the physical and chemical analyses of water. Tests revealed that 70% of samples were contaminated by Aeromonas spp., with water averaging 2.92 Log CFU/100 mL during the rainy period and 3.16 Log CFU/100 mL during the dry one. Fish contaminated by Aeromonas spp. averaged 2.58 Log CFU/100 mL during the rainy period and 3.53 Log CFU/100 mL during the dry one. Aeromonas spp. samples were multi-resistant to 2 or 8 antimicrobials in 62.5% of the samples. Ampicillin was the antimicrobial with the highest resistance percentage rate. Results showed that fish bred in amateur fish farms constituted a health risk for the population.
基金The research was carried out under Governmental Order to the Institute of Limnology RAS(subject no.FMNG-2019-0003,“Development of integrated methods for studying and evaluating the characteristics of solid particles at nanoscale size in water bodies with different levels of anthropogenic impact”).
文摘This study focuses on the analysis of seasonal dynamics of physicochemical parameters(pH and Eh)and organic matter content in the sediments accumulated within the impact zone of the cage trout farm(Lake Ladoga,Russia).The Ladoga is the largest lake in Europe and there are more than 20 fish farms located in the northern part of the waterbody.The geochemical research is necessary for predicting the negative impact of the polluted sediments on both the cage fish and the aquatic ecosystem.The sampling was conducted during various seasons of the year(February,June,August,October)which were characterized by the different fish feeding regimes.The sediment cores were collected at 7 points,including the cage and reference sites(150 m and 600 m far from the farm).The results showed that the accumulation of organic material released from the studied fish farms was local and the wastes did not enter the sediments at the control sites.Furthermore,the accumulated organic layer can be compacted and partially mineralized during winter period.Nevertheless,strongly reducing conditions in sediments occur due to the accumulation of organic material and low rate of water exchange within the studied bay.Therefore,there is a potential risk of formation of toxic gases and release of accumulated nutrients and metals from sediments to water.It can have a negative impact on benthic and nekton organisms,in particular cage fish.
文摘Ecological stoichiometry of nitrogen and phosphorus is an important indicator to characterize the nitrogen and phosphorus trophic status in aquatic ecosystems. The study of the spatio-temporal patterns of nitrogen and phosphorus stoichiometry is beneficial to the nitrogen and phosphorus pollution management in pond ecosystems. In this study, 18 groups (36 in total) of typical cascade ponds were selected as long-term observations to investigate the spatial distribution patterns of nitrogen and phosphorus component ratios (ratio of total nitrogen to phosphorus: TN:TP, ratio of dissolved nitrogen to phosphorus: TDN:TDP, ratio of particulate nitrogen to phosphorus: PN:PP) in water bodies in the tropical agricultural watershed of Jinjing. The results showed that the average values of TN:TP and TDN:TDP in the upstream ponds were 26.4 and 53.4, respectively, and were more than those in the downstream (22.95 and 48.1, respectively). In contrast, the PN:PP (13.78) in the upstream was significantly lower than that of the downstream (30.39). Furthermore, the factors of rainfall, agricultural land use and fish farming influenced the spatio-temporal variability of the N:P ratios. The ratios of TN:TP and TDN:TDP were higher in the wet season and lower in the dry season. Agricultural land use and fish farming reduced the ratios of the above three nitrogen and phosphorus components in cascade ponds in the study area. Our results show that strengthening agricultural land pollution control and aquaculture management could help to improve water quality of pond ecosystems in the study area.
文摘In this paper,we analyze the dynamical behavior of fish farm model related to Atangana-Baleanu derivative of arbitrary order.The rnodel is constituted with the group of non-linear differential equations having nutrients,fish and mussel.We have included discrete kind gestational delay of fish.The solution of fish farm model is determined by employing homotopy analysis transforms method(HATM).Existence of and uniqueness of solution are studied through Picard-Lindelof approach.The influence of order of new non-integer order derivative on nutrients,fish and mussel is discussed.The complete study reveals that the outer food supplies manage the behavior of the model.Moreover,to show the outcomes of the study,some numerical results are demonstrated through graphs.
基金This work was supported by the African Development Bank(AFDB)capacity building initiatives through Nelson Mandela African Institution of Science and Technology.
文摘Aquaculture provides significant contributions to household food security,as the capture of wild fish from lakes,dams,and oceans do not meet the current demand for animal protein in Tanzania.Sustainable aquaculture requires well-established regulatory systems and extension services for good pond management practices and maintaining fish health by fish farmers.Fish farming is practiced widely in Tanzania,from small-to large-scale ponds and these farming systems are moving from extensive normal operations(low input demand)to intensive farming(high input demand).However,the industry is largely still operating at a subsistence level with low production.Bacterial infections have been occurring in these fish farms and will continue to be an issue of concern into the future.This review highlights the current challenges,successes,and prospects towards a sustainable aquaculture industry in Tanzania,including:limited extension services mirroring the limited knowledge by farmers regarding pond management practices;the inadequacy of funds to carry out fish disease research or implement a surveillance system;little expertise in fish disease diagnosis and treatment;and poor management options.To minimize disease outbreaks and optimize production in the future,we suggest a strengthening of extension services,augmented with on-farm knowledge transfer.Emphasis should be on pond management practices and fish disease management;the creation of a well-functioning fish disease surveillance system;and strengthening collaborative research on aquaculture between the government research institutions and academia.Establishing small cooperative fish farmer groups within the Aquaculture Association of Tanzania(AAT)for easy access to information is also recommended.
文摘In Amazonia,small-oriented family businesses or communities cultivate freshwater organisms as a source of income.Although effective management is fundamental for optimizing cultivated stocks,Amazonian aquaculture belittles the importance of genetic diversity,relying primarily on phenotypical characteristics during breeders’selection.To provide a“proof of concept”built on the premise that implementing modern technologies is crucial to optimizing fish stocks in rural Amazonian fish farms,we conducted a pilot study assessing genetic diversity on cultivated Piaractus brachypomus from Caquet´a,Colombia.We used mitochondrial control region(CR)sequences to evaluate heterogeneity.Our data revealed low genetic diversity and suggested that most sampled individuals probably originated from a single maternal lineage.Haplotype diversification resulted from discrete point mutations not associated with geographical location.Polymorphisms accumulate in non-conserved CR regions,yet the most divergent haplotypes display mutations in conserved CR sequences with roles in mitochondrial metabolisms and proliferation.Overall,our results indicate a need in the local industry to design breeding strategies to enhance diversity to avoid deleterious effects caused by inbreeding and domestication.
文摘The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production and developmental sectors.However,intensification demands increased inputs,such as fish and feed per unit culture area and,therefore,increased waste generation from the aquaculture production systems.The impact of waste products from aquaculture has increased public concern and threatens the sustainability of aquaculture practices.The need for increasing the production of aquaculture products cannot be overemphasized and,therefore,there is a need to develop culture systems that will increase fish production with efficient waste management in order to limit environmental degradation resulting from aquaculture wastes and ensure its sustainability.This paper reviewed various aspects of waste production from aquaculture,their sources,components,and methods of management,in different culture systems,primarily discussing waste production from feed,chemicals,and pathogens.We aimed to establish the sources of wastes,their contents,and potential harms to both the fish culture and the environment.Suggestions for managing wastes in different culture systems were made to ensure an improved and sustainable aquaculture production.
文摘Objective:To determine the prevalence,mean intensity,and abundance of monogenean parasites in Clarias gariepinus(C.gariepinus)from two selected fish farms in Calabar,Cross River State,Nigeria.Methods:Eighty specimens of C.gariepinus from the two farms(40 each)were necropsied for parasitological analysis.Skin,gill and fin biopsies were prepared from each specimen following standard methods for microscopic analysis.Parasitological indices including dominance(D),prevalence,mean intensity and abundance were calculated according to standard formulae.Data were analyzed using the Fisher's exact test.Results:C.gariepinus from the two farms were infested with a total of ninety individuals of monogenean parasites belonging to three species including Macrogyrodactylus clarii(M.clarii),Gyrodactylus sp.and Dactylogyrus sp.D index showed that the three monogenean species were eudominant(D-value>10%).Gyrodactylus sp.was more abundant(46)followed by Dactylogyrus sp.(23)while M.clarii was the lowest(21).Prevalence,meaning intensity and abundance of monogenean parasites in the two farms,varied insignificantly higher(P>0.05).Prevalence in both farms were higher in female C.gariepinus than that in male.Monogenean parasites exhibited organ specificity as M.clarii and Dactylogyrus sp.were recovered from the gills while Gyrodactylus sp.colonized the skin and fin.Conclusions:High abundance of these parasites may lead to poor growth performance and high mortality in C.gariepinus,leading to huge monetary loss and low profit margin by increasing production cost due to the cost of treatments.
