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The extensive type of fish farming by utilizing wastewater into fish pond is a inimitable illustration of aquaculture thorough resource recycling in East Kolkata Wetland, Ramsar site in India. The current study exposed the pressure of urban effluence and poor management of use wastewater in the Ramsar site. The current paper lean-tos some lights over the quality of different water parameters and heavy-metal concentration of chromium content at EKW and their effects on prevalence of infection in fishes cultured at EKW area. Grounded on the recent study, it can be assumed that pollution level is increasing day by day at alarming rate, hence affecting the fish health severely in recent times. The incremental changes and proper management practice through pretreatment of sewage water, proper sanitation can easily solve some problems related to the pollution and fish health, may increase the fish production. Proper management practice can also reduce the probabilities of contamination of cultured aquatic organisms with perilous heavy-metals such as Chromium (Cr.) thus can also reduce the health hazards of the population of peri-urban Kolkata. [ABSTRACT FROM AUTHOR]

The current study investigated the effects of oyster mushroom Pleurotus florida, powder on mucus bactericidal activity of Catfish, Clarias batrachus fingerlings. The fingerlings were fed with diets containing 0 (control), 5, 10, 15, and 20 g of oyster mushroom powder in basal diets abis floating magur fish feed for 7 weeks. Mucus samples were collected after the 7 th week and checked for their effect on different strains of disease-causing bacteria Staphylococcus aureus, Streptococcus inane and Aeromonas hydrophila. The results of this study showed that feeding catfish with an oyster mushroom powder diet significantly stimulated bactericidal activity against different strains of bacteria in a dose and time-dependent manner. [ABSTRACT FROM AUTHOR]

This study evaluated the fillet quality parameters and the fatty acid profile of Nile tilapia subjected to transport with essential oil of Ocimum basilicum and eugenol. Fish was distributed in five treatments: N: non-transported; C: transported with water only; A: water + ethanol; E: water + eugenol; and M: water + O. basilicum. The anesthetics prevented the decrease of the fillet pH. The colorimetry a* (red) was higher for the fish fillets transported with ethanol. The water loss due to dripping was higher in fish transported in water + ethanol. The water loss due to thawing was lower in the nontransported fish fillets. The non-transported fish fillets presented a higher margaric acid content. In general, the fatty acid profile was not altered in its composition, showing that the use of eugenol and O. basilicum essential oil did not change the final quality of the fillet. [ABSTRACT FROM AUTHOR]

Lactoferrin is a mammalian cationic iron‐binding glycoprotein of the innate immune system that belongs to the transferrin family of proteins. Present in colostrum, milk and tears, and exhibiting a wide range of biological properties in vitro and in vivo, lactoferrin is a nutraceutical component used as a food supplement for humans. Evidence from veterinary medicine and animal production suggests the potential use of lactoferrin as a microbicide, microbiostatic, microbiota modulator or immunostimulant. Bovine lactoferrin is the most common type of lactoferrin in animal production research, because it is more easily produced and sold all over the world. Administering bovine lactoferrin to dairy cattle, chickens and pigs causes several physiological changes that may affect immune system behaviour, microbiota status and iron homeostasis. This could increase resistance to pathogens and, in some cases, improve growth performance. The present review analyses the in vitro and in vivo effects of bovine lactoferrin on fish species for human consumption. Although there is no consensus on how bovine lactoferrin can modify the physiology of fish in vivo, the results of in vitro assays suggest a similar molecular mechanism to that previously described in mammals. [ABSTRACT FROM AUTHOR]

A12-week experiment was conducted to evaluate the influences of thiamine ongrowth performance, and intestinal mitochondrial biogenesis and function of Megalobramaamblycephala fed a high-carbohydrate (HC) diet. Fish (24·73 (sem 0·45) g) were randomly assigned to one of four diets: two carbohydrate (CHO) levels (30 and 45 %) and two thiamine levels (0 and 1·5 mg/kg). HC diets significantly decreased DGC, GRMBW, FIMBW, intestinal activities of amylase, lipase, Na+, K+-ATPase, CK, complexes I, III and IV, intestinal ML, number of mitochondrial per field, ΔΨm, the P-AMPK: T-AMPK ratio, PGC-1β protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1β, mitochondrial transcription factor A, Opa-1, ND-1 and COX-1 and 2, while the opposite was true for ATP, AMP and reactive oxygen species, and the transcriptions of dynamin-related protein-1, fission-1 and mitochondrial fission factor. Dietarythiamine concentrations significantly increased DGC, GRMBW, intestinal activities of amylase, Na+, K+-ATPase, CK, complexes I and IV, intestinal ML, number of mitochondrial per field, ΔΨm, the P-AMPK:T-AMPK ratio, PGC-1β protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1β, Opa-1, ND-1, COX-1 and 2, SGLT-1 and GLUT-2. Furthermore, a significant interaction between dietary CHO and thiamine was observed in DGC, GRMBW, intestinal activities of amylase, CK, complexes I and IV, ΔΨm, the AMP:ATP ratio, the P-AMPK:T-AMPK ratio, PGC-1β protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1β, Opa-1, COX-1 and 2, SGLT-1 and GLUT-2. Overall, thiamine supplementation improved growth performance, and intestinal mitochondrial biogenesis and function of M. amblycephala fed HC diets. [ABSTRACT FROM AUTHOR]

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in captivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stock, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratus from the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean heterozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0.141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo Verde, Juína, and Nova Mutum. The Deviation in the Hardy-Weinberg equilibrium was observed in most of the loci in the three populations. Considering the genetic differentiation, it is concluded that the three populations are very close genetically, which requires introduction of new genetic material in the stocks to enrich them genetically for a later reproductive program. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the effects of resveratrol on the redox balance, cholesterol homeostasis and bile acid metabolism of Megalobrama amblycephala offered a high-carbohydrate diet. Fish (35.0 ± 0.15 g) were fed four diets including one control diet (32% nitrogen-free extract), one high-carbohydrate diet (45% nitrogen-free extract, HC), and the HC diet supplemented with different levels (0.04%, HCR1; 0.08%, HCR2) of resveratrol for 12 weeks. The HC diet-induced redox imbalance is characterized by increased MDA content and decreased T-SOD and CAT activities in the liver. Resveratrol attenuated this by up-regulating the transcription of Cu/Zn-sod, and increasing the activities of T-SOD, CAT, and GPX. The HC diet enhanced the cholesterol synthesis, but decreased the bile acid synthesis via up-regulating both hmgcr and acat2, and down-regulating cyp7a1, thus resulting in excessive cholesterol accumulation. Resveratrol supplement decreased cholesterol synthesis, and increased cholesterol uptake in the liver by down-regulating both hmgcr and acat2, and up-regulating ldlr. It also increased bile acid synthesis and biliary excretion by up-regulating cyp7a1, and down-regulating mrp2, oatp1, and oatp4 in the hindgut, thereby decreasing cholesterol accumulation. In conclusion, resveratrol improves the cholesterol homeostasis of Megalobrama amblycephala fed a high-carbohydrate diet by modulating the redox response and bile acid metabolism.

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in captivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stock, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratus from the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean heterozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0.141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo Verde, Juína, and Nova Mutum. The Deviation in the Hardy-Weinberg equilibrium was observed in most of the loci in the three populations. Considering the genetic differentiation, it is concluded that the three populations are very close genetically, which requires introduction of new genetic material in the stocks to enrich them genetically for a later reproductive program.

It is estimated that vibriosis account for about half of the economic losses in Asian fish culture. Consequently, the prevention and control of vibriosis is one of the priority research topics in the field of Asian fish culture disease. Relevant measures have been proposed to control some Vibrios that pose a threat to Asian fish culture, but there are currently only a few effective vaccines available to combat these Vibrios. The purpose of our review is to sum up the main prevention methods and the latest control strategies of seven Vibrio species that cause great harm to Asian aquaculture, including Vibrio harveyi, Vibrio vulnificus, Vibrio parahaemolyticus, Vibrio mimicus, Vibrio anguillarum, Vibrio alginolyticus and Vibrio cholerae. Strategies such as antibiotics, probiotics, bacteriophages, antimicrobials from plants and other natural sources, as well as vaccines, are compared and discussed here. We expect this review will provide some new views and recommendations for the future better prevention and control of vibriosis in Asian fish culture.

The present study was conducted to evaluate the utilization of both pelleted feed (PF) and extruded feed (EF) by blunt snout bream Megalobrama amblycephala based on growth performance, stress responses, innate immunity and disease resistance. Both the PF and EF were prepared with the same formula. Fish were divided randomly into 2 groups, including one fed the PF continuously and one offered the EF continuously. The whole feeding trial lasted 8 weeks, after which fish were subjected to Aeromonas hydrophila infection. The results showed that the feed intake, feed conversion ratio, hepatic total superoxide dismutase activity and glutathione content, plasma complement 3 and complement 4 levels as well as myeloperoxidase activity of the EF group were all significantly lower than those of the PF group, while the opposite was true for the condition factor, the viscera index, the abdominal fat percentage, nitrogen and energy retention, hepatic malondialdehyde content, plasma levels of cortisol, glucose, lactate, total protein and globulin as well as the activities of plasma alanine aminotransferase and aspartate aminotransferase. In addition, the EF group also obtained relatively low activities of hepatic glutathione peroxidase and plasma acid phosphatase as well as high cumulative mortality rates at 24–96 h after Aeromonas hydrophila challenge. Furthermore, the feed cost of culturing this species with EF is lower than that with PF. These findings indicated that compared with PF, EF could increase the feed utilization and economic benefits of blunt snout bream, but reduce its anti‐stress ability, non‐specific immunity, A. hydrophila resistance and feed cost. [ABSTRACT FROM AUTHOR]

Maclura tinctoria is a tree species native from Brazil and rich in phenolic compounds. Since plant antibacterial activity is highly associated with phenolic compound concentration, we aim to evaluate the in vitro antimicrobial activity of different extracts against fish pathogenic bacteria. In addition, some phenolic compounds have central depressant effects and can be useful in aquaculture due to possible sedative and/or anesthetic effects. Four M. tinctoria extracts were extracted separately with ethanol; leaves (LE), bark (BE), heartwood (HE), and the sapwood (SE). In vitro antimicrobial activity was tested against Aeromonas strains at concentrations of 6400 to 3.125 μg/mL. The sedative effect was evaluated for 24 h with 30 and 100 mg/L concentrations. Chemical composition was analyzed by HPLC-DAD-MS. The HE extract had the best MIC (400 μg/mL) and MBC (800 μg/mL) compared to the LE, BE, and SE extracts. LE extract induced deep sedation and the BE, SE, and HE extracts induced light sedation. Additionally, BE, SE, and HE induced a normal behavior without side effects. Polyphenolic compounds with antimicrobial activity and sedative effects were identified mainly in HE. Thus, HE extract is safe and can be used as a sedative for silver catfish. [ABSTRACT FROM AUTHOR]

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Although the application of treated wastewater in irrigation is a common practice in Jordan, there are no studies on its use in fish culture. In this study, physical, chemical and biological characteristics of an artificial lake containing mixture of treated wastewater and rainwater were assessed to examine whether the nutrient loading is sufficient for fish culture. The study also evaluated the suitability of the lake's water quality for irrigation after fish farming. The study was conducted in outdoor tanks fed with water from the artificial lake and stocked with three types of fish (Tilapia, Carp and Koi). The diversity of phytoplankton communities in the lake's produces natural food for Carp and Koi and promotes their growth with maximum per cent survival of 89% and 56% respectively. In addition, remarkable improvement in all water quality parameters after fish culture was observed. [ABSTRACT FROM AUTHOR]

The production and application of biochar has become increasingly popular in the past 10 years. Biochar has similar characteristics to charcoal and activated charcoal: they are all pyrogenic carbonaceous matter derived from organic carbon-rich materials and produced by pyrolysis. Studies related to the incorporation of biochar in animal feed are limited. This review summarizes major studies related to the use of biochar as a feed additive for ruminants (cattle and goats), pigs, poultry (chickens and ducks) and fish. Documented positive responses to biochar supplementation include improved growth performance, blood profiles, egg yield, ability to resist pathogens including gut pathogenic bacteria and a reduction of methane production by ruminant animals. In addition, the high sorption capacity of biochar efficiently aids the removal of pollutants and toxins from animals' bodies as well as from farm environments. It is expected that there will be increasing use of biochar in animal farming. The potential use of biochar in the medical and human health sectors should also be explored. [ABSTRACT FROM AUTHOR]

The effect of silkworm-derived polysaccharide silkrose on fish ectoparasites was investigated. When juvenile yellowtail (Seriola quinqueradiata) fed diets containing silkrose were artificially infected with Benedenia seriolae, a fish ectoparasite, the numbers of parasitized B. seriolae were significantly lower compared to that in fish in the control group without silkrose treatment. Furthermore, when juvenile yellowtails were severely infected with B. seriolae, no mortality was observed in the silkrose-treated group, compared to more than 60% in the control group. In field studies carried out at a fish farm with yellowtail and white trevally (Pseudocaranx dentex), oral treatment with silkrose significantly reduced B. seriolae parasitism in yellowtail and Caligus longipedis and Neobenedenia girellae parasitism in white trevally. Silkrose treatment also reduced blood levels of cortisol, a stress hormone in both species. The changes in gene expression in the epidermis of yellowtail by silkrose treatment were also investigated, showing that the expression of various genes, including factors involved in immunity, stress response, and wound healing, was changed by the treatment. These findings indicate that silkworm-derived silkrose effectively prevents infection by external parasites in yellowtail and white trevally.

Sub Saharan African (SSA) population which is expected to reach 1,998 million in 2050, is undergoing a demographic transition with an average annual growth rate of 3.7% and an increase in the agricultural population of 1.9%. During the same period, aggregate agricultural food production increased only 2.6%. Meeting food needs should therefore be achieved by improving the labor productivity of farmers in SSA. In rural and peri-urban SSA, most of the people are smallholder farmers and are resource limited. They live on agriculture and to address the various challenges they face and to increase productivity, several strategies have been developed in the search for a model of agricultural development that is more equitable, more ecological and more socially viable. The adoption of integrated agriculture aquaculture system (IAA) fits in this framework. The IAA system has been adapted to SSA from Asia based on its achievements. The adoption of IAA is particularly positive for farmers in topographical conditions allowing a variety of activities within the farm including a fish pond. These variants of IAA system are various forms of adaptation to agricultural practices of each tropical region. During its application in SSA, IAA system has presented advantages as well as disadvantages but especially its opens to future opportunity for significant improvement. This paper reviews the evolution of this integrated system since its adoption in SSA and elucidates the strengths, constraints and future opportunity of this system.

In aquaculture, constructed wetland (CW) has recently attracted attention for use in effluent purification due to its low running costs, high efficiency and convenient operation,. However, less data are available regarding the long-term efficiency of farm-scale CW for cleaning effluents from inland freshwater fish farms. This study investigated the effectiveness of CW for the removal of nutrients, organic matter, phytoplankton, heavy metals and microbial contaminants in effluents from a blunt snout bream (Megalobrama amblycephala) farm during 2013–2018. In the study, we built a farm-scale vertical subsurface flow CW which connected with a fish pond, and its performance was evaluated during the later stage of fish farming. The results show that CW improved the water quality of the fish culture substantially. This system was effective in the removal of nutrients, with a removal rate of 21.43–47.19% for total phosphorus (TP), 17.66–53.54% for total nitrogen (TN), 32.85–53.36% for NH4+-N, 33.01–53.28% NH3-N, 30.32–56.01% for NO3−-N and 42.75–63.85% for NO2−-N. Meanwhile, the chlorophyll a (Chla) concentration was significantly reduced when the farming water flowed through the CW, with a 49.69–62.01% reduction during 2013–2018. However, the CW system only had a modest effect on the chemical oxygen demand (COD) in the aquaculture effluents. Furthermore, concentrations of copper (Cu) and lead (Pb) were reduced by 39.85% and 55.91%, respectively. A microbial contaminants test showed that the counts of total coliform (TC) and fecal coliform (FC) were reduced by 55.93% and 48.35%, respectively. In addition, the fish in the CW-connected pond showed better growth performance than those in the control pond. These results indicate that CW can effectively reduce the loads of nutrients, phytoplankton, metals, and microbial contaminants in effluents, and improve the water quality of fish ponds. Therefore, the application of CW in intensive fish culture systems may provide an advantageous alternative for achieving environmental sustainability.

Domestication of new candidate species remains a long and difficult process often resulting in unfruitful attempts. Early steps in most domestication programmes often consider species as a unity, disregarding a part of the biodiversity: the wild intraspecific geographic differentiation. Yet, this differentiation can shape local specificities, which could lead to different domestication predisposition or socio‐economic attractiveness between populations. Therefore, considering this population‐specific potential could facilitate domestication and subsequent production of new candidate species. Here, we propose a three‐step integrative approach to standardise and facilitate new domestication attempts by taking advantage of wild geographic differentiation. Step 1 consists of classifying the wild biodiversity to identify prospective units (i.e. groups of differentiated allopatric populations). Step 2 allows comparing performances of these units in standardised conditions (i.e. rearing system) through a multifunction and multi‐trait assessment. Finally, step 3 highlights units with higher aquaculture potentials through the calculation of an aquaculture potential score. This approach, here applied to fish culture for human consumption, also aims at being extended to other taxa (e.g. crustaceans, molluscs) and other production goals. [ABSTRACT FROM AUTHOR]

Integrated agri-aquaculture systems (IAAS) have been studied as an option for fish production in communities with limited resources. Likewise, the use of periphyton has recently become a viable alternative for its contribution of low-cost natural food. The effect of periphyton use on the productive yield of a hybrid cachama and bocachico polyculture in IAAS, was studied in the Jimaín Indigenous community, Colombia. For this experiment, 1.5 hybrid cachama and 1.5 bocachico fingerlings/m2 were stocked with average weights of 0.49 ± 0.14 g and 1.83 ± 1.61 g, respectively, in six 90 m2 land ponds; three of these ponds had wooden dowels (three dowels/m2) for periphyton fixation. The growth evaluation lasted 135 days. The treatments (WS: with substrate and WOS: without substrates) received a supplementary diet, adjusted as a percentage of the biomass with biweekly adjustment, twice a day. Biometrics were performed every two weeks. The productive data by species and for the polyculture were evaluated using an ANOVA with a general linear model (p <0.05). Weight (g) and standard length (cm) data by species were evaluated using a mixed model of repeated measures. No substrate effects were found on the productive parameters analyzed for each species as well as for the polyculture. A significant interaction was observed for bocachico weight on day 90 (WS: 74.7 and WOS: 47.1). According to the obtained results, optimizing the use of periphyton and the management of native species polyculture requires further studies. [ABSTRACT FROM AUTHOR]

A six month feeding experiment was conducted to compare between different diets and its effect on growth performance of an indigenous carp Bangana dero. A total of 360 uniform B. dero (average weight 4.9±0.02 g) were cultured in twelve circular fibreglass tanks @ 15 fish per tank (90 W X 64 H cm.). The fishes were fed by two commercial feeds (T1, T2), formulate feed (T3) and control feed (T4) in triplicates with 4% of body weight twice a day. Fish were maintained in well aerated water system. Analysis of variance showed that the growth performance in T1 was significantly higher than other groups (p<0.05). The formulate diet also had uniform growth rate with significant positive effects on Specific Growth Rate (SGR) and final biomass gain. The present study reveals that there is potential effect of commercial and formulated fish feed on growth performances of this target species. [ABSTRACT FROM AUTHOR]

Dissolved oxygen (DO) as one of the most fundamental parameters of water quality plays a vital role in aquatic life. This study was conducted to predict DO, biological oxygen demand (BOD), and chemical oxygen demand (COD) in an intensive rainbow trout rearing system with different biomass (B). The multilayer perceptron (MLP) and the radial basis function (RBF) neural networks were employed for evaluating the impacts of food parameters (crude protein (CP), consumed feed (CF)), fish parameters (different values of B, and weight gain (WG)), and water quality parameters including temperature (T) and flow rate (Q) on variation of DO, BOD, and COD concentrations. This study's results showed that although both MLP and RBF neural networks are capable to estimate DO, BOD, and COD concentrations, RBF neural network showed better performance compared to MLP neural network. The results of sensitivity analysis indicated that the parameter CF has the highest effect on DO concentration estimation. Independent variables CF, CP, WG, and B showed the highest to the lowest rank of impacts on BOD estimation, respectively. The results also illustrated a decreasing trend of the effects on the estimation error of COD changes simulation by all independent variables, including B, T, WG, CF, CP, and Q, respectively. RBF neural network based on better stability and generalization ability with average root mean square error (RMSE) and mean absolute percentage error (MAPE) values of less than 0.12 and 3% was superior to MLP in DO, BOD, and COD concentration prediction. Moreover, CF was identified as the most effective factor in estima12tion process. Based on the present study results, there are direct relationships between DO, BOD, and COD concentrations and water quality parameters, fish parameters, and food parameters. Food parameters relative to fish and water quality parameters imposed the greatest effects. Improvement in feeding process such as application of intelligence feeding methods and change in fish diet and feeding time can considerably reduce losses in production system. [ABSTRACT FROM AUTHOR]

The study made an evaluation to the effects of saltwater intrution in the Shatt Al-Arab river on the fish culture activites. Data reveals noticeable increase of investment in fresh water carp fish culture during the years 2009, 2010 and the next years. The documents of Basrah Agriculture Directerate indicated that 48 earthern ponds of an area nearly 3778 Acres were licensed and furthermore, nearly 380 floating fish cage farms were licensed about 26120 m2 area which represents the actual worked 1277 cages. However, the approved number of given licensed farms were 514 farms with at least 16 cages to each farm, which potentially can be invested a water area nearly 98688 m², calculated to a cage of 4 x 3 x 2 (m²) dimentions. The total estimated production of earthern ponds was 3778–4723 t. annually, and that of floating cages farms was 3266–7800 t. annually. The total financial income of fish production in Basra proviance is estimated to be about 26133–35883 billion Iraqi dinar and more than 3000 persons were involved in the sector of fishculture and fisheries. The acute successive increases of salinity that Shatt Al-Arab river experienced, particularly during 2018 were caused large fish mortality and many fish farms were closed and have had very negative effects on the fish sector in Basrah proviance. [ABSTRACT FROM AUTHOR]