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1.
Braz J Biol ; 83: e246333, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468517

RESUMO

Fish protein is serving as a source of nutrition for protein starving world. However, sustainable aquaculture products require inexpensive plant by-products due to finite sources of fish meal. Therefore, this study was conducted to examine nutrient utilization, growth performance and hematological indices of Cirrhinus mrigala fingerlings fed on Moringa oleifera leaf meal (MOLM) based diets. Fish were fed with six isonitrogenous and isoenergetic diets having MOLM as a substitute of fish meal (FM) at the levels of 0%, 10%, 20%, 30%, 40% and 50% for the period of 90 days. Fingerlings having initial weight 6.35±0.04g were reared in triplicate tanks at the stocking density of 15 and hand fed at the rate of 5% of total biomass twice regularly. Chromic oxide inclusion level was 1% in diets. After analysis, maximum growth performance and improved digestibility of nutrients were found in fish fed with diet at 10% replacement level as compared to fish fed on control diet and other test diets. Additionally, it was found that the red blood cells, white blood cells, hemoglobin and mean corpuscular hemoglobin concentration of fish showed a significantly (p<0.05) inverse correlation with the increase in MOLM. In present research, it was concluded that MOLM has good potential to be used as a FM substitute in C. mrigala diet with maximum effect at 10% showing positive hematological indices.


Assuntos
Cyprinidae , Moringa oleifera , Ração Animal/análise , Animais , Aquicultura , Dieta
2.
Braz J Biol ; 83: e248878, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468535

RESUMO

Biofloc technology is much highlighted these days because of its tremendous effects on aquaculture. Microbes were enriched on cheapest organic carbon source i. e., powdered banana peels and were incorporated in different aquaria rearing grass carp fingerlings under different C/N treatments (10:1, 15:1 and 20:1) and 10% water daily water exchange. The initial growth of fingerlings was recorded. The experiment was settled in triplicates for 60 days and run parallel to control group provided with commercial feed and daily water exchange. Its effect was evaluated by measuring the growth of fingerlings and water parameters of each aquarium. The average % gain in weight and length of fingerlings was obtained significantly highest (28.12 ± 0.30g and 17.29 ± 0.46cm respectively) in aquaria containing pure powdered banana peels with 10% water exchange and C/N ratio was adjusted at 20: 1 (T3) than other treatments and control. Ammonia and other water parameters were also under control in T3 than other experimental and control groups. By all counts, it was concluded that the highest C/N ratio in biofloc system had the potential to increment C. idella growth rate by reducing toxicity and could be used as fish meal substitute.


Assuntos
Aquicultura , Carpas , Amônia , Ração Animal/análise , Animais , Carbono
3.
J Hazard Mater ; 416: 125931, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492861

RESUMO

Contamination characteristics, equilibrium partitioning and risk assessment of phthalate esters (PAEs) were investigated in seawater, sediment and biological samples collected from the Xiangshan Bay area during an annual investigation between January and November 2019. PAE concentrations detected in the mariculture environment in surface seawater, sediment, and biological samples were 172-3365 ng/L, 190-2430 µg/kg (dry weight [dw]), and 820-4926 µg/kg (dw), respectively. The dominant congeners in different media included di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), and di(2-ethylhexyl) phthalate (DEHP). The inner bay and the bay mouth were the gathering area of PAEs and heavily influenced by the mariculture activities, river inputs, and anthropogenic activities. The bioaccumulation of PAEs demonstrated benthic feeding fishes with relatively high trophic levels concentrated high levels of phthalates. The mobility of PAEs in sediment-seawater showed that the transfer tendency of low-molecular weight species was from the sediment to the water, which was in contrast with those of high-molecular weight PAEs. DEHP, DiBP and DnBP had various degrees of ecological risks in the aquatic environment, whereas only the DiBP posed potential risks in sediments. The current assessment of carcinogenic and noncarcinogenic risks posed by fish consumption were within acceptable limits for humans.


Assuntos
Ésteres , Ácidos Ftálicos , Aquicultura , China , Dibutilftalato , Humanos , Ácidos Ftálicos/toxicidade , Plásticos/toxicidade , Medição de Risco
4.
Rev Sci Tech ; 40(2): 567-584, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34542092

RESUMO

Investments in animal health and Veterinary Services can have a measurable impact on the health of people and the environment. These investments require a baseline metric that describes the burden of animal health and welfare in order to justify and prioritise resource allocation and from which to measure the impact of interventions. This paper is part of a process of scientific enquiry in which problems are identified and solutions sought in an inclusive way. It poses the broad question: what should a system to measure the animal disease burden on society look like and what value would it add? Moreover, it aims to do this in such a way as to be accessible by a wide audience, who are encouraged to engage in this debate. Given that farmed animals, including those raised by poor smallholders, are an economic entity, this system should be based on economic principles. These poor farmers are negatively impacted by disparities in animal health technology, which can be addressed through a mixture of supply-led and demand-driven interventions, reinforcing the relevance of targeted financial support from government and non-governmental organisations. The Global Burden of Animal Diseases (GBADs) Programme will glean existing data to measure animal health losses within carefully characterised production systems. Consistent and transparent attribution of animal health losses will enable meaningful comparisons of the animal disease burden to be made between diseases, production systems and countries, and will show how it is apportioned by people's socio-economic status and gender. The GBADs Programme will produce a cloud-based knowledge engine and data portal, through which users will access burden metrics and associated visualisations, support for decisionmaking in the form of future animal health scenarios, and the outputs of wider economic modelling. The vision of GBADs, strengthening the food system for the benefit of society and the environment, is an example of One Health thinking in action.


Assuntos
Doenças dos Animais , Saúde Única , Doenças dos Animais/epidemiologia , Animais , Aquicultura , Gado
5.
Animal ; 15(9): 100317, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34340140

RESUMO

Mosaicism is frequently observed in aquaculture practices, and it adversely affects the production as well as the restoration programme of the sturgeon. The purpose of the present study was the induction of 2n/3n mosaic in sterlet, Acipenser ruthenus L., and compare their embryonic and larval development with diploid control sterlet. Microsatellite DNA loci genotyping was conducted for the identification of the genotypes and parentage analysis. Embryonic development was monitored in experimental groups at every 24 h interval. Identification of individual stages of embryonic development was recorded based on a 36-degree scale of development. Additionally, the BW and body length (LT) of experimental fishes were taken during 110 days of the rearing period. The Fulton's condition coefficient (F), length-weight parameters, and specific growth rate (SGR) coefficient were calculated. The analysis of embryonic development of the 2n/3n mosaic and the diploid control group did not show differences. However, higher mortality (88%) was observed in 2n/3n mosaic groups in comparison to the diploid control groups (55%). BW and body length of 2n/3n mosaic sterlet were slightly lower than the diploid control sterlet, but the differences were not statistically significant. F analysis did not confirm a lower growth performance of the fishes in the 2n/3n mosaic group. Microsatellite DNA loci genotyping confirmed both the incidence of polyspermy and retention of the second polar body. This paper presents the first report on embryonic development and growth performance of 2n/3n mosaic sturgeons.


Assuntos
Aquicultura , Peixes , Animais , Desenvolvimento Embrionário , Repetições de Microssatélites
6.
Int J Mol Sci ; 22(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34360628

RESUMO

Macroalgae are the source of many harmful allelopathic compounds, which are synthesized as a defense strategy against competitors and herbivores. Therefore, it can be predicted that certain species reduce aquaculture performance. Herein, the allelopathic ability of 123 different taxa of green, red, and brown algae have been summarized based on literature reports. Research on macroalgae and their allelopathic effects on other animal organisms was conducted primarily in Australia, Mexico, and the United States. Nevertheless, there are also several scientific reports in this field from South America and Asia; the study areas in the latter continents coincide with areas where aquaculture is highly developed and widely practiced. Therefore, the allelopathic activity of macroalgae on coexisting animals is an issue that is worth careful investigation. In this work, we characterize the distribution of allelopathic macroalgae and compare them with aquaculture locations, describe the methods for the study of macroalgal allelopathy, present the taxonomic position of allelopathic macroalgae and their impact on coexisting aquatic competitors (Cnidaria) and herbivores (Annelida, Echinodermata, Arthropoda, Mollusca, and Chordata), and compile information on allelopathic compounds produced by different macroalgae species. This work gathers the current knowledge on the phenomenon of macroalgal allelopathy and their allelochemicals affecting aquatic animal (competitors and predators) worldwide and it provides future research directions for this topic.


Assuntos
Alelopatia , Aquicultura , Invertebrados , Defesa das Plantas contra Herbivoria , Alga Marinha/metabolismo , Animais , Herbivoria , Alga Marinha/genética
7.
Viruses ; 13(7)2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34372583

RESUMO

The present study was intended to screen the wild crustaceans for co-infection with Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV) and White Spot Syndrome Virus (WSSV) in Andaman and Nicobar Archipelago, India. We screened a total of 607 shrimp and 110 crab samples using a specific polymerase chain reaction, and out of them, 82 shrimps (13.5%) and 5 (4.5%) crabs were found positive for co-infection of IHHNV and WSSV. A higher rate of co-infection was observed in Penaeus monodon and Scylla serrata than other shrimp and crab species. The nucleotide sequences of IHHNV and WSSV obtained from crab in this present study exhibited very high sequence identity with their counterparts retrieved from various countries. Histopathological analysis of the infected shrimp gill sections further confirmed the eosinophilic intra-nuclear cowdry type A inclusion bodies and basophilic intra-nuclear inclusion bodies characteristics of IHHNV and WSSV infections, respectively. The present study serves as the first report on co-infection of WSSV and IHHNV in Andaman and Nicobar Archipelago, India and accentuates the critical need for continuous monitoring of wild crustaceans and appropriate biosecurity measures for brackishwater aquaculture.


Assuntos
Braquiúros/virologia , Coinfecção/epidemiologia , Penaeidae/virologia , Animais , Animais Selvagens/virologia , Aquicultura/métodos , Densovirinae/genética , Densovirinae/patogenicidade , Índia , Reação em Cadeia da Polimerase/métodos , Vírus da Síndrome da Mancha Branca 1/genética , Vírus da Síndrome da Mancha Branca 1/patogenicidade
8.
Artigo em Inglês | MEDLINE | ID: mdl-34351256

RESUMO

Four Gram-stain-negative, catalase- and oxidase-positive, rod-shaped and motile strains (Y26, Y57T, ZJ14WT and RP18W) were isolated from mariculture fishponds in PR China. Comparisons based on 16S rRNA gene sequences showed that strains Y26 and Y57T share 16S rRNA gene sequence similarities in the range of 95.1-98.5 % with species of the genus Bowmanella, and strains ZJ14WT and RP18W share 16S rRNA gene sequence similarities in the range of 96.7 -98.8 % with species of the genus Amphritea, respectively. The genome sizes of strains Y26, Y57T, ZJ14WT and RP18W were about 4.85, 5.40, 4.70 and 4.70 Mbp with 49.5, 51.7, 51.2 and 51.3 mol% G+C content, respectively. The calculated pairwise OrthoANIu values among strains Y26, Y57T and species of the genus Bowmanella were in the range of 72.6-83.1 %, but the value between strains Y26 and Y57T was 96.2 %. The pairwise OrthoANIu values among strains ZJ14WT, RP18W and other species of the genus Amphritea were all less than 93.9 %, but the value between strains ZJ14WT and RP18W was 99.3 %. Q-8 was the major respiratory quinone of strains Y26, Y57T, ZJ14WT and RP18W, and the major fatty acids of these strains were all C16 : 1 ω7c, C16 : 0 and C18 : 1 ω7c. The predominant polar lipids of strains Y26 and Y57T included phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylinositol, but strains ZJ14WT and RP18W only contained phosphatidylethanolamine and phosphatidylglycerol. Combining phenotypic, biochemical and genotypic characteristics, strains Y26 and Y57T should belong to the same species and represent a novel member of the genus Bowmanella, and strains ZJ14WT and RP18W should belong to the same species and represent a novel member of the genus Amphritea, for which the names Bowmanella yangjiangensis sp. nov. (type strain Y57T=GDMCC 1.2180T=KCTC 82439T) and Amphritea pacifica sp. nov. (type strain ZJ14WT=GDMCC 1.2203T=KCTC 82438T) are proposed.


Assuntos
Alteromonadaceae/classificação , Aquicultura , Filogenia , Lagoas/microbiologia , Alteromonadaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Arch Virol ; 166(10): 2763-2778, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34342747

RESUMO

White spot syndrome virus (WSSV) is a significant threat to the aquaculture sector, causing mortality among crabs and shrimps. Currently available diagnostic tests for WSSV are not rapid or cost-effective, and a new detection method is therefore needed. This study demonstrates the development of a biosensor by functionalization of magnetosomes with VP28-specific antibodies to detect WSSV in seafood. The magnetosomes (1 and 2 mg/ml) were conjugated with VP28 antibody (0.025-10 ng/µl), as confirmed by spectroscopy. The magnetosome-antibody conjugate was used to detect the VP28 antigen. The binding of antigen to the magnetosome-antibody complex resulted in a change in absorbance. The magnetosome-antibody-antigen complex was then concentrated and brought near a screen-printed carbon electrode by applying an external magnetic field, and the antigen concentration was determined using impedance measurements. The VP28 antigen (0.025 ng/µl) bound more efficiently to the magnetosome-VP28 antibody complex (0.025 ng/µl) than to the VP28 antibody (0.1 ng/µl) alone. The same assay was repeated to detect the VP28 antigen (0.01 ng/µl) in WSSV-infected seafood samples using the magnetosome-VP28 antibody complex (0.025 ng/µl). The WSSV in the seafood sample was also drawn toward the electrode due to the action of magnetosomes controlled by the external magnetic field and detected using impedance measurement. The presence of WSSV in seafood samples was verified by Western blot and RT-PCR. Cross-reactivity assays with other viruses confirmed the specificity of the magnetosome-based biosensor. The results indicate that the use of the magnetosome-based biosensor is a sensitive, specific, and rapid way to detect WSSV in seafood samples.


Assuntos
Técnicas Biossensoriais/veterinária , Magnetossomos , Alimentos Marinhos/virologia , Vírus da Síndrome da Mancha Branca 1/isolamento & purificação , Animais , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Aquicultura , Reações Cruzadas , Espectroscopia Dielétrica , Ensaio de Imunoadsorção Enzimática , Microbiologia de Alimentos , Magnetossomos/química , Magnetossomos/imunologia , Penaeidae/virologia , Reprodutibilidade dos Testes , Proteínas do Envelope Viral/análise , Proteínas do Envelope Viral/imunologia , Vírus da Síndrome da Mancha Branca 1/imunologia
11.
Microb Pathog ; 159: 105123, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34364977

RESUMO

Aeromonas veronii is a comorbid pathogen that can infect humans, and animals including various aquatic organisms. In recent years, an increasing number of cases of A. veronii infection has been reported, indicating serious risks. This bacterium not only threatens public health and safety but also causes considerable economic loss in the aquaculture industry. Currently, some understanding of the pathogenic mechanism of A. veronii has been obtained. In this study, we first constructed the A. veronii TH0426 fis gene deletion strain Δfis and the complementation strain C-fis through homologous recombination technology. The results showed that the adhesion and invasion ability of the Δfis strain towards Epithelioma papulosum cyprini (EPC) cells and the cytotoxicity were 3.8-fold and 1.38-fold lower, respectively, than those of the wild-type strain. In the zebrafish infection model, the lethality of the deleted strain is 3-fold that of the wild strain. In addition, the bacterial load of the deletion strain Δfis in crucian carp was significantly lower than the wild-type strain, and the load decreased with time. In summary, deletion of the fis gene led to a decrease in the virulence of A. veronii. Our research results showed that the deletion of the fis gene significantly reduces the virulence and adhesion ability of A. veronii TH0426. Therefore, the fis gene plays a vital role in the pathogenesis of A. veronii TH0426. This preliminary study of the function of the fis gene in A. veronii will help researchers further understand the pathogenic mechanism of A. veronii.


Assuntos
Aeromonas , Carpas , Infecções por Bactérias Gram-Negativas , Aeromonas/genética , Aeromonas veronii/genética , Animais , Aquicultura , Infecções por Bactérias Gram-Negativas/veterinária , Humanos , Virulência , Peixe-Zebra
12.
Sci Total Environ ; 795: 148846, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34247068

RESUMO

Marine heatwaves (MHWs) are impacting marine biodiversity, including fisheries and aquaculture. However, it is largely unknown which species will be able to endure MHWs and at what price. Here, we applied elevated temperature (2 °C above ambient) and two different heatwave scenarios to adults of the economically important Sydney rock oyster (SRO, Saccostrea glomerata), and evaluated the impact on nutritional properties, gene expression profiles and immune health indicators. We found that elevated temperature (23 °C) and a variable heatwave (VHW) during winter caused some significant differences in the micronutrient and trace elements levels in oyster flesh. There was an increase of lead under VHW and a decrease in chromium, barium and aluminium under elevated temperature. Conversely, gene expression profiles and other physiological parameters, including flesh protein, fatty acid profiles and hemocyte numbers, were not affected by MHWs. These results indicate that adult SRO are reasonably resilient, and should continue to provide high-quality seafood, under near-future ocean warming and moderate heatwave scenarios.


Assuntos
Ostreidae , Animais , Aquicultura , Pesqueiros , Estações do Ano
14.
Artigo em Inglês | MEDLINE | ID: mdl-34292144

RESUMO

Two Gram-stain-negative, catalase-positive, oxidase-negative, rod-shaped, non-flagellated, non-spore-forming and non-motile strains (YJ13CT and H41T) were isolated from a mariculture fishpond in PR China. Comparisons based on 16S rRNA gene sequences indicated that YJ13CT and H41T shared 16S rRNA gene sequences similarities between 92.6 and 99.2 % with species of the genus Algoriphagus. YJ13CT only shared 93.8 % 16S rRNA gene sequence similarity with H41T. The reconstructed phylogenetic and phylogenomic trees indicated that YJ13CT and H41T clustered closely with species of the genus Algoriphagus. The calculated pairwise orthologous average nucleotide identity with usearch (OrthoANIu) values between strains YJ13CT and H41T and other related strains were all less than 79.5 %. The OrthoANIu value between YJ13CT and H41T was only 69.9 %. MK-7 was the predominant respiratory quinone of YJ13CT and H41T and their major cellular fatty acids contained iso-C15 : 0, C16 : 1 ω7c and C17 : 1 ω9c. The polar lipids profiles of YJ13CT and H41T consisted of phosphatidylethanolamine and several kinds of unidentified lipids. Combining the above descriptions, strains YJ13CT and H41T represent two distinct novel species of the genus Algoriphagus, for which the names Algoriphagus pacificus sp. nov. (type strain YJ13CT=GDMCC 1.2178T=KCTC 82450T) and Algoriphagus oliviformis sp. nov. (type strain H41T=GDMCC 1.2179T=KCTC 82451T) are proposed.


Assuntos
Aquicultura , Bacteroidetes/classificação , Filogenia , Lagoas/microbiologia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
15.
Chemosphere ; 281: 130796, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289641

RESUMO

This paper describes the fabrication, modification, and evaluation of the performance of thin-film composite (TFC) forward osmosis (FO) membranes for lab-scale aquaculture wastewater recovery using various fumed silica (SiO2) nanoparticles. The active polyamide (PA) layers of these membranes were novelly modified using different types of pretreated SiO2 nanoparticles [virgin SiO2, dried SiO2, and 3-aminopropyltriethoxysilane (APTES)-modified SiO2] and concentrations (0.05, 0,1, 0,2, and 0.4 wt%) to improve the membrane hydrophilicity with minimum particle agglomeration. Results show that the APTES-SiO2 modified membrane had the highest water flux and selectivity, followed by the dried-SiO2 modified membrane. The APTES coupling agent notably reduced the SiO2 aggregation on the membrane surface and improved membrane hydrophilicity. Consequently, high permeate flux and an acceptable reverse solute flux were observed. The optimal SiO2 concentration for PA modification was 0.1 wt% for all the nanoparticle types. The virgin and APTES-SiO2 modified membranes were used for aquaculture wastewater recovery. The water recovery rate reached 47% in 84 h when using the APTES-SiO2 modified membrane, while it reached only 26% in 108 h when using the virgin membrane. With a suitable design of the filtration apparatus and choice of draw solution (DS), the prepared novel TFC-FO membrane containing APTES-modified SiO2 can be used for recycling aquaculture wastewater into the DS, which can then be reused for other purposes.


Assuntos
Nanopartículas , Purificação da Água , Aquicultura , Membranas Artificiais , Osmose , Dióxido de Silício , Águas Residuárias
16.
Fish Physiol Biochem ; 47(4): 1243-1255, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34226986

RESUMO

The effects of stocking density on growth performance, serum biochemistry, digestive enzymes, immune response, and muscle quality of largemouth bass (Micropterus salmoides) reared in nine in-pond raceway systems (IPRS, 22.0 m × 5.0 m × 2.0 m) were studied. M. salmoides with initial an body weight of 8.25 ± 0.51 g and body length of 6.99 ± 0.44 cm were reared at an initial stocking density of 90.91 ind./m3 (low stocking density, LSD), 113.63 ind./m3 (middle stocking density, MSD), and 136.36 ind./m3 (high stocking density, HSD) with triplication. After 300 days of culture, MSD recorded the highest final body weight, weight gain, specific growth rate, and yield, but the food conversion ratio in MSD was the lowest. The viscerosomatic index in LSD was significantly higher than other groups. The fish serum reared at HSD showed significantly lower total protein, higher total cholesterol, triglyceride, total bilirubin, glucose content, alanine transaminase, and aspartate transaminase activity. Significantly lower intestinal amylase, lipase, trypsin activities, hepatic superoxide dismutase (SOD) and catalase (CAT) activities, and higher malondialdehyde content were detected in HSD compared to others. The content of crude lipid, saturated fatty acid decreased, and total essential amino acid, delicious amino acid, and polyunsaturated fatty acid increased in muscle with stocking density increase. No significant difference was observed in muscle texture. Profitability analysis indicated the benefit-to-cost ratio varied between 1.10 and 1.68, of which MSD was significantly higher than others. The optimal stocking density for M. salmoides should be 113.63 ind./m3 in an IPRS farm.


Assuntos
Aquicultura/métodos , Bass , Alanina Transaminase/sangue , Aminoácidos/metabolismo , Amilases/metabolismo , Animais , Aspartato Aminotransferases/sangue , Bass/sangue , Bass/crescimento & desenvolvimento , Bass/imunologia , Bass/metabolismo , Catalase/metabolismo , Ácidos Graxos/metabolismo , Proteínas de Peixes/sangue , Imunidade , Intestinos/enzimologia , Lipase/metabolismo , Fígado/metabolismo , Músculos/química , Esteróis/sangue , Superóxido Dismutase/metabolismo , Triglicerídeos/sangue , Tripsina/metabolismo
17.
Bioresour Technol ; 338: 125529, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34265592

RESUMO

Removal of nitrogenous and phosphorus compounds from aquaculture wastewater by green microalgae (Tetraselmis sp.) was investigated using a novel method of algal cell immobilization. Immobilized microalgae removed nitrogenous and phosphorous compounds efficiently from aquaculture wastewater. Results showed that Tetraselmis beads reduced significantly (p < 0.05) the total ammonia nitrogen, nitrite nitrogen and soluble reactive phosphorous concentration (0.08; 0.10 and 0.17 mg/L, respectively) from the initial concentration of 7.7, 3.1 and 2.0 mg/L respectively within 48 h compared to other treatments. Removal rate of total ammonia nitrogen, nitrite nitrogen and soluble reactive phosphorous were 99.2, 99.2 and 94.3% respectively, for the artificial wastewater within 24 h. For the shrimp pond wastewater, total ammonia nitrogen, nitrite nitrogen and soluble reactive phosphorous were reduced 98.9, 97.7 and 91.1% respectively within 48 h. It is concluded that Tetraselmis sp. beads is an effective means to reduce nitrogen and phosphorus levels in aquaculture wastewater.


Assuntos
Microalgas , Compostos de Fósforo , Aquicultura , Biomassa , Nitrogênio/análise , Fósforo , Águas Residuárias
18.
Sensors (Basel) ; 21(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209710

RESUMO

Red tides caused by Margalefidinium polykrikoides occur continuously along the southern coast of Korea, where there are many aquaculture cages, and therefore, prompt monitoring of bloom water is required to prevent considerable damage. Satellite-based ocean-color sensors are widely used for detecting red tide blooms, but their low spatial resolution restricts coastal observations. Contrarily, terrestrial sensors with a high spatial resolution are good candidate sensors, despite the lack of spectral resolution and bands for red tide detection. In this study, we developed a U-Net deep learning model for detecting M. polykrikoides blooms along the southern coast of Korea from PlanetScope imagery with a high spatial resolution of 3 m. The U-Net model was trained with four different datasets that were constructed with randomly or non-randomly chosen patches consisting of different ratios of red tide and non-red tide pixels. The qualitative and quantitative assessments of the conventional red tide index (RTI) and four U-Net models suggest that the U-Net model, which was trained with a dataset of non-randomly chosen patches including non-red tide patches, outperformed RTI in terms of sensitivity, precision, and F-measure level, accounting for an increase of 19.84%, 44.84%, and 28.52%, respectively. The M. polykrikoides map derived from U-Net provides the most reasonable red tide patterns in all water areas. Combining high spatial resolution images and deep learning approaches represents a good solution for the monitoring of red tides over coastal regions.


Assuntos
Dinoflagelados , Proliferação Nociva de Algas , Aquicultura , República da Coreia
19.
Braz J Biol ; 83: e244480, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259780

RESUMO

The objective of this study was to evaluate the properties of garlic as a growth promoter in larvae of angelfish Pterophyllum scalare and its benefits during transport of juveniles of this species. The experiment was conducted in recirculation aquaculture system, consisting of 20 tanks of 40 L equipped with independent water input and output. We used 1,400 larvae distributed among five treatments, with four repetitions, which totaled 20 experimental units. The treatments were 0, 50, 100, 200, and 400 mg of garlic extract per kilo of feed. The results showed that the inclusion of levels of garlic extract in the feed did not significantly effect the fish's development or their transport. Neither did the inclusion of levels of garlic extract affect the survival of the larvae during the trial period. New research with extracts of higher dosages should be performed to elucidate the effect of garlic extract as a growth promoter.


Assuntos
Ciclídeos , Alho , Animais , Aquicultura , Larva , Extratos Vegetais/farmacologia
20.
Dis Aquat Organ ; 145: 165-172, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34263731

RESUMO

Meagre Argyrosomus regius is a potential candidate for Mediterranean aquaculture diversification, although several health issues still represent important bottlenecks for its sustainable production, including systemic granulomatosis (SG). To evaluate the SG progression in meagre during a 10 mo period of cage ongrowing, a histopathological investigation was carried out on 108 meagre fed 3 different diets (commercial pellets, hydrated commercial pellets and defrosted sardines). Histological sections of the gills and visceral organs were examined and lesions referable to SG scored from 1-3 according to the severity of the granulomatosis. The kidney and liver were the most affected organs, showing the highest percentage of positivity for granulomas and severity of lesions along the whole observation period. Using a statistical mixed model (GLMM) followed by odds ratio analysis, an effect of diet and temperature was found: the severity of liver and digestive tract SG scores decreased in the Cage 3 group (defrosted sardines) and with increasing temperature (p < 0.05, negative estimates, odds ratio <1). These observations, in accordance with the literature, suggest that SG in meagre could be related to nutritional-metabolic factors with the possible influence of environmental factors such as temperature.


Assuntos
Perciformes , Animais , Aquicultura , Dieta/veterinária , Brânquias , Fígado
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