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1.
Aquat Toxicol ; 222: 105453, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32112997

RESUMO

Anti-parasitic drugs used in the aquaculture industry are discharged to the sea after treatment of salmon. In this study, the effects of azamethiphos (AZA) in the Salmosan® formulation and deltamethrin (DEL) in the Alpha Max® formulation, have been assessed in Northern shrimp larvae (Pandalus borealis) when administered both separately and in combination. The exposure concentrations were 100 ng/L for AZA and 2 ng/L for DEL, each representing a 1000-fold dilution of the prescribed concentrations for salmon. These two chemicals were combined at these concentrations to give a third treatment (AZA + DEL). When larvae were exposed for two hours on the first, second and third days post hatch (dph), significantly increased mortality and reduced swimming activity were observed for larvae from the DEL and combined AZA + DEL treatments 4 dph, though not in larvae from the AZA treatment. A single pulse exposure, delivered on the first day post hatch, caused similar effects on mortality and swimming activity 4 dph as the three-pulse exposure. Mortality was driven by the presence of DEL in both experiments, with no amplification or reduction of effects observed when DEL and AZA were combined. Larvae were observed for 13 days following the single pulse exposure, with food limitation introduced as an additional stressor on day 4. In the DEL and AZA + DEL treatments mortality continued to increase regardless of food level, with no larvae completing development to stage II. The overriding toxicity of DEL masked any potential effects the reduced food ration may have exerted. Swimming activity was lower for AZA treated larvae than Control larvae 13 dph, when both groups were fed daily, though no other significant changes to mortality, development to stage II, feeding rate or gene expression were observed. Food limited Control and AZA larvae had lower swimming activity and feeding rate than daily fed Control larvae, with expression of pyruvate kinase and myosin genes also downregulated. However, there was no negative effect on survival or successful development to stage II in these treatments. In addition, mesencephalic astrocyte-derived neurotropic factor was downregulated in food limited Control larvae when compared with the daily fed Controls. Results from this study together with reported estimates of dispersion plume concentrations of discharged pesticides indicate that toxic concentrations of deltamethrin could reach shrimp larvae several kilometers from a treated salmon farm.


Assuntos
Ração Animal , Aquicultura/métodos , Larva/efeitos dos fármacos , Pandalidae/efeitos dos fármacos , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Nitrilos/toxicidade , Organotiofosfatos/toxicidade , Piretrinas/toxicidade , Salmão/crescimento & desenvolvimento
2.
PLoS One ; 15(2): e0223813, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32109243

RESUMO

Cholesterol metabolism is greatly affected in fish fed plant-based diet. The regulation of cholesterol metabolism is mediated by both transcriptional factors such as sterol regulatory element-binding proteins (SREBPs) and liver X receptors (LXRs), and posttranscriptional factors including miRNAs. In mammals, SREBP-2 and LXRα are involved in the transcriptional regulation of cholesterol synthesis and elimination, respectively. In mammals, miR-33a is reported to directly target genes involved in cholesterol catabolism. The present study aims to investigate the regulation of cholesterol metabolism by SREBP-2 and LXRα and miR-33a in rainbow trout using in vivo and in vitro approaches. In vivo, juvenile rainbow trout of ~72 g initial body weight were fed a total plant-based diet (V) or a marine diet (M) containing fishmeal and fish oil. In vitro, primary cell culture hepatocytes were stimulated by graded concentrations of 25-hydroxycholesterol (25-HC). The hepatic expression of cholesterol synthetic genes, srebp-2 and miR-33a as well as miR-33a level in plasma were increased in fish fed the plant-based diet, reversely, their expression in hepatocytes were inhibited with the increasing 25-HC in vitro. However, lxrα was not affected neither in vivo nor in vitro. Our results suggest that SREBP-2 and miR-33a synergistically enhance the expression of cholesterol synthetic genes but do not support the involvement of LXRα in the regulation of cholesterol elimination. As plasma level of miR-33a appears as potential indicator of cholesterol synthetic capacities, this study also highlights circulating miRNAs as promising noninvasive biomarker in aquaculture.


Assuntos
Colesterol/metabolismo , Receptores X do Fígado/fisiologia , MicroRNAs/fisiologia , Oncorhynchus mykiss/metabolismo , Receptores Acoplados a Proteínas-G/fisiologia , Animais , Aquicultura/métodos , Células Cultivadas , Hepatócitos/metabolismo , Metabolismo dos Lipídeos
3.
Chemosphere ; 247: 125821, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31972484

RESUMO

Water quality has significant impacts on the health and immune responses of aquaculture species. This study aimed to analyse and compare the effects of two biological filters namely, gravel and, Bio-Ball with a recently developed filter called Water-cleanser on regulation of water quality parameters, health and immune response of marron reared in plastic tanks for 60 days. Results showed that addition of Bio-Ball significantly (P < 0.05) reduced the concentration of ammonia, nitrate and phosphate while Water-cleanser showed the ability to reduce ammonia and nitrate from water in aquaculture tanks. Although the biological filters had no significant effect on marron growth but inclusion of Bio-Ball and Water-cleanser positively influenced the biochemical composition of tail muscle and some haemolymph parameters of marron. The next generation sequence data demonstrated higher bacterial diversity in the hindgut of marron with Water-cleanser, followed by Bio-Ball and gravel, respectively. In addition, the predicted metabolic pathways revealed a significantly higher bacterial activity and gene function correlated to metabolism and biosynthesis of protein, energy and secondary metabolites in Bio-Ball and Water-cleanser. Bio-Ball and Water-cleanser were also associated with up-regulation of innate immune responsive genes of marron gut. Overall, Bio-Ball and Water-cleanser proved to have higher water remediation and immune response modulation capabilities, and therefore could be used as preferred filters for growth of beneficial bacteria in crayfish culture.


Assuntos
Aquicultura/métodos , Astacoidea/microbiologia , Filtração/métodos , Microbioma Gastrointestinal , Nível de Saúde , Imunidade , Qualidade da Água , Animais , Biodiversidade , Filtração/normas , Água Doce , Hemolinfa , Imunidade/genética
4.
PLoS One ; 15(1): e0227106, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951624

RESUMO

Identifying strategies to maintain seafood supply is central to global food supply. China is the world's largest producer of seafood and has used a variety of production methods in the ocean including domestic capture fisheries, aquaculture (both freshwater and marine), stock enhancement, artificial reef building, and distant water fisheries. Here we survey the outcomes of China's marine seafood production strategies, with particular attention paid to the associated costs, benefits, and risks. Benefits identified include high production, low management costs, and high employment, but significant costs and risks were also identified. For example, a majority of fish in China's catches are one year-old, ecosystem and catch composition has changed relative to the past, wild and farmed stocks can interact both negatively and positively, distant water fisheries are a potential source of conflict, and disease has caused crashes in mariculture farms. Reforming China's wild capture fisheries management toward strategies used by developed nations would continue to shift the burden of production to aquaculture and could have negative social impacts due to differences in fishing fleet size and behavior, ecosystem structure, and markets. Consequently, China may need to develop novel management methods in reform efforts, rather than rely on examples from other large seafood producing countries. Improved accounting of production from fisheries and aquaculture, harmonization and centralization of historical data sets and systematic scientific surveys would improve the knowledge base for planning and evaluating future reform.


Assuntos
Aquicultura/normas , Custos e Análise de Custo , Alimentos Marinhos/normas , Aquicultura/economia , Aquicultura/métodos , China , Conservação dos Recursos Naturais , Alimentos Marinhos/economia
5.
PLoS One ; 15(1): e0227812, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31971955

RESUMO

Sustainability standards are used to assure improved environmental performance in the aquaculture sector. But standard setters face limitations in including a broad range of producers with different capabilities, which in turn reduces their scope and impact. Drawing on Sen's capability approach, we introduce a novel way to assess the extent to which sustainability standards can support the capability of farmers to make prescribed improvements to their production practices. In doing so, we compare four shrimp aquaculture standards (Aquaculture Stewardship Council, Global Aquaculture Alliance, Southeast Asian Shrimp Aquaculture Improvement Protocol and the Thai Agricultural Standard) based on an analysis of what we label the 'prescribed capitals' and 'bundle of capitals' that underpin the compliance capability of producers. The results show that standards narrowly prescribe standards requiring human capital, while there is potential for prescribing a wider bundle of social, financial and physical capitals that can allow more flexible standard compliance. The findings raise the prospect of redesigning sustainability standards to support a broader diversity of producer capabilities and, in turn, increase their overall impact.


Assuntos
Aquicultura/métodos , Pesqueiros , Animais , Aquicultura/economia , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Decápodes/crescimento & desenvolvimento , Ecossistema , Pesqueiros/economia , Humanos , Frutos do Mar/provisão & distribução
6.
Sci Total Environ ; 704: 135266, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31831234

RESUMO

The present study aimed to formulate diets using soybean dreg to replace part of fish meal (30% and 60%) and to incorporate dietary supplement to the diets with papain to promote fish growth and decrease total cost of feed formulations for gold-lined seabream (Rhabdosargus sarba). In Experiment 1, papain was used to supplement feeds containing soybean dreg to replace part of the fish meal. In Experiment 2, bromelain and a microalgae supplement were used to supplement feeds containing soybean substitutes as a replacement of the fish meal. Results from Experiment 1 indicated that the growth performance of fish fed diets with up to 60% replacement of fishmeal with soybean residues predigested with papain were not significantly different (p > 0.05) from the control (a formula developed by Agriculture, Fisheries and Conservation Department (AFCD), which contained 49.4% fishmeal, 45.2% raw trashfish, 4.9% alpha starch and 0.5% vitamin premix). It indicated that plant protein predigested with a small amount of enzyme supplement (e.g. papain) can be used to replace fish meal in traditional fish diets, and the cost could subsequebtly be reduced. In Experiment 2, the diets containing bromelain, soybean dreg pre-digested with bromelain and supplemented with microalgae resulted in significantly better growth performance than other diet groups. Results from the present study suggested that predigesting soybean dreg with enzymes could replace up to 60% fishmeal in the moist pellets while achieving economic benefits.


Assuntos
Ração Animal , Aquicultura/métodos , Dourada , Soja , Animais , Fabaceae , Perciformes
7.
Sci Total Environ ; 701: 134794, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31715479

RESUMO

Multiple lines of evidence, ranging from time series field observations to climate change stimulation experiments demonstrate the negative effects of global warming and ocean acidification (OA) on bivalve molluscs. The impact of global warming on bivalve aquaculture has recently been reviewed. However, the impact of OA on bivalve aquaculture has received relatively less attention. Although there are many reports on the effects of OA on bivalves, this information is poorly organized and the connection between OA and bivalve aquaculture is unclear. Therefore, understanding the potential impact of acidification on ecosystems and bivalve aquaculture is of prime importance. Here, we provide a comprehensive scientific review of the impact of OA on bivalves and propose mitigation measures for future bivalve farming. This information will help to establish aquaculture and fisheries management plans to be implemented in commercial fisheries and nature conservation. In general, scientific evidence suggests that OA threatens bivalves by diminishing the availability of carbonate minerals, which may adversely affect the development of early life stages, calcification, growth, byssus attachment and survival of bivalves. The Integrated multi-trophic aquaculture (IMTA) approach is a useful method in slowing the effects of climate change, thereby providing longer adaptation period for bivalves to changing ocean conditions. However, for certain regions that experience intense OA effects or for certain bivalve species that have much longer generational time, IMTA alone may not be sufficient to protect bivalves from the adverse effects of climate change. Therefore, it is highly recommended to combine IMTA and genetic breeding methods to facilitate transgenerational acclimation or evolution processes to enhance the climate resilience of bivalves.


Assuntos
Aquicultura/métodos , Bivalves , Animais , Aquecimento Global , Concentração de Íons de Hidrogênio , Oceanos e Mares , Água do Mar/química
8.
Arch Virol ; 165(2): 387-396, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31865470

RESUMO

A pathogen of significance in the aquaculture sector, the Gram-negative marine bacterium Vibrio parahaemolyticus causes gastroenteritis associated with consumption of improperly prepared seafood. This bacterium can be controlled using lytic bacteriophages as an alternative to antibiotics. Ï•VP-1 is a lytic phage of V. parahaemolyticus that was isolated from an aquafarm water sample with the aim of assessing its potential as a bio-control agent and determining its physicochemical properties and genomic sequence. Morphological analysis by transmission electron microscopy and phylogenetic analysis based on the large terminase subunit gene showed that this phage belongs to the family Myoviridae. It could infect multiple-drug-resistant (MDR) V. parahaemolyticus and V. alginolyticus strains of mangrove and seafood origin. With a maximum adsorption time of 30 min, ϕVP-1 has a short latent period of 10 min with burst size of 44 particles/cell. Whole-genome sequencing was done using the Illumina platform, and annotation was done using GeneMarkS and Prodigal. The 150,764bp genome with an overall G+C content of 41.84% had 203 putative protein-encoding open reading frames, one tRNA gene, and 66 predicted promoters. A number of putative DNA replication and regulation, DNA packaging and structure, and host lysis genes were identified. Comparison of the ϕVP-1 genome sequence to those of known Vibrio phages indicated little discernible DNA sequence similarity, suggesting that ϕVP-1 is a novel Vibrio phage. Sequence analysis revealed the presence of 64 potential ORFs with a T4-like genomic organization. In silico analysis suggested an obligate lytic life cycle and showed the absence of lysogeny or virulence genes. The complete sequence of Ï•VP-1 was annotated and deposited in the GenBank database (accession no. MH363700). The genetic features of this novel phage suggest that it might be applicable for phage therapy against pathogenic strains of V. parahaemolyticus.


Assuntos
Bacteriófagos/genética , Resistência a Múltiplos Medicamentos/genética , Genoma Viral/genética , Myoviridae/genética , Vibrio parahaemolyticus/virologia , Aquicultura/métodos , Composição de Bases/genética , Biofilmes , Genômica/métodos , Fases de Leitura Aberta/genética , Terapia por Fagos/métodos , Filogenia
9.
Sensors (Basel) ; 19(24)2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31847169

RESUMO

A sensing configuration for the real-time monitoring, detection, and quantification of dissolved carbon dioxide (dCO2) was developed for aquaculture and other applications in freshwater and saline water. A chemical sensing membrane, based on a colorimetric indicator, is combined with multimode optical fiber and a dual wavelength light-emitting diode (LED) to measure the dCO2-induced absorbance changes in a self-referenced ratiometric scheme. The detection and processing were achieved with an embeded solution having a mini spectrometer and microcontroller. For optrode calibration, chemical standard solutions using sodium carbonate in acid media were used. Preliminary results in a laboratory environment showed sensitivity for small added amounts of CO2 (0.25 mg·L-1). Accuracy and response time were not affected by the type of solution, while precision was affected by salinity. Calibration in freshwater showed a limit of detection (LOD) and a limit of quantification (LOQ) of 1.23 and 1.87 mg·L-1, respectively. Results in saline water (2.5%) showed a LOD and LOQ of 1.05 and 1.16 mg·L-1, respectively. Generally, performance was improved when moving from fresh to saline water. Studies on the dynamics of dissolved CO2 in a recirculating shallow raceway system (SRS+RAS) prototype showed higher precision than the tested commercial sensor. The new sensor is a compact and robust device, and unlike other sensors used in aquaculture, stirring is not required for correct and fast detection. Tests performed showed that this new sensor has a fast accurate detection as well as a strong potential for assessing dCO2 dynamics in aquaculture applications.


Assuntos
Aquicultura/métodos , Dióxido de Carbono/análise , Águas Salinas/análise , Colorimetria , Monitoramento Ambiental/métodos , Fibras Ópticas
10.
PLoS One ; 14(12): e0218360, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31887112

RESUMO

Microbial ingredients such as Candida utilis yeast are known to be functional protein sources with immunomodulating effects whereas soybean meal causes soybean meal-induced enteritis in the distal intestine of Atlantic salmon (Salmo salar L.). Inflammatory or immunomodulatory stimuli at the local level in the intestine may alter the plasma proteome profile of Atlantic salmon. These deviations can be helpful indicators for fish health and, therefore potential tools in the diagnosis of fish diseases. The present work aimed to identify local intestinal tissue responses and changes in plasma protein profiles of Atlantic salmon fed inactive dry Candida utilis yeast biomass, soybean meal, or combination of soybean meal based diet with various inclusion levels of Candida utilis. A fishmeal based diet was used as control diet. Inclusion of Candida utilis yeast to a fishmeal based diet did not alter the morphology, immune cell population or gene expression of the distal intestine. Lower levels of Candida utilis combined with soybean meal modulated immune cell populations in the distal intestine and reduced the severity of soybean meal-induced enteritis, while higher inclusion levels of Candida utilis were less effective. Changes in the plasma proteomic profile revealed differences between the diets but did not indicate any specific proteins that could be a marker for health or disease. The results suggest that Candida utilis does not alter intestinal morphology or induce major changes in plasma proteome, and thus could be a high-quality alternative protein source with potential functional properties in diets for Atlantic salmon.


Assuntos
Ração Animal/microbiologia , Candida/crescimento & desenvolvimento , Salmo salar/crescimento & desenvolvimento , Ração Animal/análise , Criação de Animais Domésticos/métodos , Animais , Aquicultura/métodos , Dieta , Expressão Gênica , Intestinos/fisiologia , Proteínas , Proteoma/metabolismo , Proteômica , Soja
11.
Rev Sci Tech ; 38(2): 615-628, 2019 Sep.
Artigo em Inglês, Francês, Francês | MEDLINE | ID: mdl-31866672

RESUMO

Successful selective breeding programmes have been under way in aquacultural species for many decades. Gains in growth rate as high as 900% have been reported. Programmes selecting for resistance and/or tolerance of specific pathogens have had similar success. However, no more than 10-20% of global aquaculture production is sourced from well-documented breeding programmes. Direct selection for resistance and/or tolerance in biosecure breeding programmes is difficult when classical breeding methods are used. Genomic selection is widely expected to become the most effective mode of selection against pathogens in fish and shellfish. In this paper, the authors explore the possible negative effects of genetic improvement programmes, especially those that stem from interactions between genetics and other components of the aquaculture production system, particularly disease. The main focus is the interaction between selective breeding and biosecurity. They suggest that a self-amplifying feedback loop can be created when biosecurity regulation causes a progressive reduction in genetic diversity and an increase in inbreeding, especially in smallholder hatcheries and farms in developing countries. The resulting inbreeding depression causes increased susceptibility to disease, which in turn increases the frequency and severity of epizootics. Greater losses due to disease again increase regulatory pressures and the cycle begins once more. This 'biosecurity-agro-economic-genetic' feedback loop is analogous to an 'extinction vortex' in wild populations. The authors believe that the loop can be broken by biosecure, aquacultural, genetic exchange networks, modelled on existing breed associations for terrestrial domestic animals. Such networks would constitute a global aquacultural gene pool, with enhanced environmental resilience, long-term capacity for adaptation and minimal inbreeding depression. However, such networks will also require innovative new pathogen management procedures, documentation and regulations to facilitate the exchange of broodstock and seed while still maintaining effective biosecurity.


Assuntos
Aquicultura/métodos , Cruzamento/métodos , Domesticação , Animais , Aquicultura/normas , Cruzamento/normas , Variação Genética , Endogamia , Modelos Genéticos , Densidade Demográfica
12.
Bull Environ Contam Toxicol ; 103(6): 814-821, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606772

RESUMO

To understand the toxic mechanism of ammonia and identify effective biomarkers on the oxidative stress for the fish Carassius auratus red var., acute and chronic toxicity tests were conducted. The 96-h LC50 of total ammonia nitrogen (TAN) for C. auratus was 135.4 mg L-1, the corresponding unionized ammonia (NH3) concentration was 1.5 mg L-1. The activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione-peroxidase (GSH-Px) and glutathione (GSH) showed an increase with a subsequent falling, while the malondialdehyde (MDA) increased during the chronic test. The SOD, MDA, and GSH could be effective biomarkers to evaluate the TAN oxidative stress, the maximum acceptable toxicant concentration (MATC) was 11.3 mg L-1 for TAN. To our knowledge, this is the first study to propose biomarkers to evaluate potential environmental risk and establish a risk threshold for TAN in C. auratus.


Assuntos
Amônia/toxicidade , Aquicultura/métodos , Monitoramento Ambiental/métodos , Carpa Dourada/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , China , Relação Dose-Resposta a Droga , Carpa Dourada/metabolismo , Dose Letal Mediana , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Urbanização
13.
Ecotoxicol Environ Saf ; 186: 109752, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31605954

RESUMO

Tilapias are cultured globally and are rising in acceptance as the most important freshwater aquaculture species. Monitoring of serum biomarkers is a promising tool in aquaculture to screen the health status as they are virtuous indicators of extreme stress and organ dysfunction in fish. The present study examined the serum biomarkers of oxytetracycline (OTC)-dosed Nile tilapia Oreochromis niloticus at 0, 80 and 800 mg/kg biomass/day, i.e., 0X, 1X, and 10X the approved dose (X = 80 mg OTC/kg biomass/day) for 10 consecutive days. The fish biomass and levels of serum glucose, aspartate aminotransferase, alanine aminotransferase, creatinine and C-reactive protein (CRP) were determined at scheduled intervals. A significant dose-dependent reduction in fish biomass during the OTC-dosing (5.84%) and post-OTC dosing (8.16%) periods was observed. All the serum biomarkers of Nile tilapia increased significantly on day 10 OTC-dosing. Though their levels reduced significantly, normalcy was not achieved even after 42 days of cessation of OTC-dosing, except CRP. The CRP reached the normal level on day 25 post-OTC dosing in the 1X group. The results, thus, demonstrated that the oral OTC-dosing influences the physiological state of apparently healthy Nile tilapia in a dose-dependent manner. These changes were, however, reversible upon discontinuation of OTC-dosing. The set of data observed on growth reduction and elevated serum biomarker levels even after 42 days of cessation of OTC-dosing, thus, raises questions on the utility of oral OTC-dosing.


Assuntos
Ração Animal , Antibacterianos/efeitos adversos , Aquicultura/métodos , Ciclídeos/fisiologia , Dieta , Oxitetraciclina/efeitos adversos , Estresse Fisiológico/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Biomassa , Glicemia/metabolismo , Proteína C-Reativa/metabolismo , Ciclídeos/sangue , Ciclídeos/crescimento & desenvolvimento , Creatina/sangue , Humanos , Índia , Alimentos Marinhos , Tilápia
14.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1595-1600, set.-out. 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038643

RESUMO

O objetivo deste trabalho foi determinar a digestibilidade do farelo de palmiste (Elaeis guineensis) para o tambaqui (Colossoma macropomum), em duas classes de peso: 1 (210 alevinos de 4,45±1,18g) e 2 (54 juvenis de 115,91±4,01g). Os coeficientes de digestibilidade aparente (CDA) da matéria seca, proteína bruta e energia bruta do farelo de palmiste foram avaliados pela metodologia de substituição da dieta referência, utilizando-se 0,1% de óxido crômico como indicador externo. Os dados foram analisados pelo teste t de Student, a 5% de probabilidade. Os CDAs da matéria seca, proteína bruta e energia bruta do ingrediente foram iguais (P>0,05) nas classes de peso avaliadas. Os CDAs observados nas classes 1 e 2, respectivamente, foram: matéria seca (17,52% e 20,75%), proteína bruta (62,83% e 63,75%) e energia bruta (14,16% e 22,43%). A capacidade do tambaqui para digerir os nutrientes do farelo de palmiste não foi influenciada pelo peso corporal, e o aproveitamento satisfatório da proteína (63,29%) faz desse ingrediente uma potencial fonte alternativa de proteína em dietas para a espécie.(AU)


The objective of this work was to determine the digestibility of palm kernel meal (Elaeis guineensis) in tambaqui (Colossoma macropomum), in two weight classes: 1 (210 fingerlings of 4.45±1.18g) and 2 (54 juveniles of 115.91±4.01g). The apparent digestibility coefficients (ADC) of dry matter, crude protein and crude energy of the palm kernel meal were evaluated by the substitution of the reference diet methodology, using 0.1% chromic oxide as an external indicator. Data were analyzed by Student's t-test at 5% probability. The dry matter, crude protein and crude energy ADCs of the ingredient were the same (P> 0.05) in the weight classes evaluated. The ADCs observed in classes 1 and 2, respectively, were: dry matter (17.52% and 20.75%), crude protein (62.83% and 63.75%) and crude energy (14.16% and 22.43%). The ability of tambaqui to digest the nutrients of palm kernel meal was not influenced by body weight, and satisfactory protein utilization (63.29%) makes this ingredient a potential alternative source of protein in diets for the species.(AU)


Assuntos
Elaeis guineensis , Aquicultura/métodos , Characidae/crescimento & desenvolvimento , Resíduos de Alimentos , Ração Animal/análise
15.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1601-1608, set.-out. 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038644

RESUMO

Com o presente estudo, objetivou-se avaliar o tempo de fornecimento de náuplios de artêmia e o período de transição alimentar para pós-larvas de acará-severo (Heros severus). Foram utilizadas 450 pós-larvas de acará-severo, distribuídas em 45 aquários, em delineamento inteiramente ao acaso, em esquema fatorial 3x5, com três repetições. Foram avaliados três períodos de fornecimento de náuplios de artêmia: zero, cinco e 10 dias. Além disso, foram testados cinco períodos de transição alimentar: um, dois, três, quatro e cinco dias, quando os animais receberam alimentação conjunta de náuplios de artêmia e dieta farelada. Ao final do experimento, os peixes foram contados, pesados e fotografados, para avaliação do desempenho produtivo e das variáveis morfométricas. Para todos os parâmetros avaliados, não foi constatada interação entre o tempo de fornecimento de artêmia e o período de transição alimentar. Os animais alimentados por 10 dias com náuplios de artêmia apresentaram os melhores resultados de desempenho e as maiores variáveis morfométricas. Os peixes que receberam alimentação conjunta por três dias apresentaram desenvolvimento satisfatório. Dessa forma, recomendam-se 10 dias de fornecimento de náuplios de artêmia e três dias de transição alimentar, antes de se iniciar o fornecimento exclusivo de dieta inerte para pós-larvas de acará-severo.(AU)


The aim of this study was to evaluate the supply time of artemia and the period of food transition to post-larvae of severum (Heros severus). A total of 450 post-larvae of severum were distributed in 45 aquaria, in a completely randomized design, in a 3x5 factorial scheme, with three replicates. Three feeding periods with artemia nauplii were evaluated: zero, five, and ten days. In addition, five feeding transitions were tested: one, two, three, four and five days, when the animals received joint feeding of artemia nauplii and dry diet. At the end of the experiment the fish were counted, weighed and photographed, to evaluate the productive performance and the morphometric variables. For all parameters evaluated, no interaction between the time of artemia supply and the feeding transition period was observed. Animals fed for 10 days with artemia nauplii showed the best performance results and the highest morphometric variables. The fish that received joint feeding for three days presented satisfactory development. Thus, 10 days of artemia nauplii supply and three days of feeding transition is recommended before starting the exclusive supply of diet inert to post-larvae of severum.(AU)


Assuntos
Animais , Artemia , Aquicultura/métodos , Ciclídeos/crescimento & desenvolvimento , Dieta/veterinária , Larva/crescimento & desenvolvimento
16.
Fish Shellfish Immunol ; 94: 697-704, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561027

RESUMO

The employment of traditional bait and medicament in freshwater aquaculture causes the frequent occurrence of environmental pollution and disease. Effluent collected after Rhodopseudomonas capsulatus-mediated wastewater treatment could be re-utilized as microbial feeds, medicament, and aquaculture water to culture Tilapia mossambica. Therefore, a novel integrated system of wastewater treatment using effluent containing R. capsulatus that improves yield, increases disease resistance, and enhances the quality of aquaculture water for Tilapia mossambica culture was proposed and investigated. Tilapia mossambica can grow well in effluent containing R. capsulatus (ER). The survival rate, yield, and whole body composition of the ER group were all increased compared to the control group (CK). The biochemical (B vitamin) and other substances in the effluent of R. capsulatus enhanced the activity of AKP, ACP, phagocytic, SOD and CAT by upregulating the expression of AKP, ACP, SOD and CAT genes. Theoretical analysis showed that biochemical molecules regulate the expression of these gene and enzyme activities by acting as a signal that stimulates the active center. Moreover, biochemical molecules present in R. capsulatus enhanced the activity of the mTOR and NF-kB signaling pathways. Furthermore, R. capsulatus inhibited Aeromonas hydrophila that increases resistance against fish disease. Meanwhile, R. capsulatus in the effluent also improved the aquaculture water quality. This technology would save the aquaculture water, reduce water pollution and wastewater discharge, and increase the output and disease resistance of Tilapia mossambica, simultaneously.


Assuntos
Aquicultura/métodos , Doenças dos Peixes/imunologia , Rhodobacter capsulatus/química , Tilápia/imunologia , Eliminação de Resíduos Líquidos/métodos , Aeromonas hydrophila/fisiologia , Animais , Resistência à Doença/genética , Regulação da Expressão Gênica/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , NF-kappa B/genética , Distribuição Aleatória , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/genética , Águas Residuárias/microbiologia
17.
J Fish Dis ; 42(11): 1573-1586, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31506962

RESUMO

The aims of the present study were to describe the salmon lice (Lepeophtheirus salmonis Krøyer, 1837) situation in an intensive salmon production area in mid-Norway and to consider implications of changing practices of how salmon lice infestation can be controlled. The results in this study suggest that there are steps that can be carried out to keep salmon lice under control even during years when the temperature facilitates a quick salmon lice development. The present work indicates that the use of cleaner fish can delay the time it takes adult female lice to reach 0.1 per salmon in the beginning of a production cycle. It suggests that the timing of cleaner fish deployment into salmon cages can influence its effectiveness in controlling salmon lice. It also gives caution to letting salmon lice develop unchecked, even at levels far below the current lice limit, because of the difficulties to control salmon lice when the external infection pressure is too high. This study took place during a rapid change in delousing methods, in an area with coordinated salmon production. Despite its exploratory nature, this study offers insights into the salmon lice fluctuations in relation to efforts aimed at controlling it.


Assuntos
Aquicultura/métodos , Copépodes/fisiologia , Ectoparasitoses/veterinária , Doenças dos Peixes/prevenção & controle , Salmo salar , Animais , Ectoparasitoses/parasitologia , Ectoparasitoses/prevenção & controle , Doenças dos Peixes/parasitologia , Noruega
18.
Sci Total Environ ; 694: 133664, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31398646

RESUMO

Inorganic­nitrogen removal is essential for the sustainable operation of aquaculture industry and also influences the health of aquatic animals, which may be accomplished by utilizing biofloc technology. In this paper, we studied the use of three different carbon sources 1) longan seed powder (LP), 2) Poly(ß-hydroxybutyrate-ß-hydroxyvalerate) (PHBV) and 3) synthesized PHBV and LP (PHBVL) in biofloc systems for 90days to investigate the nitrogen dynamics and gut microbiota of Nile tilapia (Oreochromis niloticus). The PHBVL and PHBV groups had higher total inorganic­nitrogen removal efficiencies (70.99±19.45% and 63.54±19.44%) than the LP group (35.02±11.21%), which had an accumulation of nitrate. Meanwhile, the biofloc in PHBVL and PHBV group generally had a higher amino acid composition, particularly for methionine and lysine, but was not reflected in the tilapia muscle. High-throughput sequencing indicated that the different carbohydrates shaped different bacterial community compositions in the fish gut after exposure in the three environments for 90-day. These differences, which resulted in different gut digestive enzyme activities (amylase, lipase and trypsin), and growth performance, which the food conversion ratio in the PHBVL group was lower than LP and PHBV group, the final body weight in PHBVL group was average 4.33% and 3.65% bigger than in LP and PHBV group. Network analysis revealed that the keystone taxa (90.33%) were Proteobacteria, Chloroflexi, Actinobacteria, Planctomycetes, Verrucomicrobia and Bacteroidetes, which relative abundance varied in the fish gut in the three groups. The experiment verified the feasibility and advantage to use biodegradable polymers (BDPs) as carbohydrates for biofloc systems.


Assuntos
Ciclídeos/microbiologia , Poliésteres/química , Animais , Aquicultura/métodos , Biodegradação Ambiental , Microbioma Gastrointestinal , Nitrogênio , Ciclo do Nitrogênio
19.
Fish Shellfish Immunol ; 93: 631-640, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377431

RESUMO

Fish aquaculture is the world's fastest growing food production industry and infectious diseases are a major limiting factor. Vaccination is the most appropriate method for controlling infectious diseases and a key reason for the success of salmonid cultivation and has reduced the use of antibiotics. The development of fish vaccines requires the use of a great number of experimental animals that are challenged with virulent pathogens. In vitro cell culture systems have the potential to replace in vivo pathogen exposure for initial screening and testing of novel vaccine candidates/preparations, and for batch potency and safety tests. PBL contain major immune cells that enable the detection of both innate and adaptive immune responses in vitro. Fish PBL can be easily prepared using a hypotonic method and is the only way to obtain large numbers of immune cells non-lethally. Distinct gene expression profiles of innate and adaptive immunity have been observed between bacterins prepared from different bacterial species, as well as from different strains or culturing conditions of the same bacterial species. Distinct immune pathways are activated by pathogens or vaccines in vivo that can be detected in PBL in vitro. Immune gene expression in PBL after stimulation with vaccine candidates may shed light on the immune pathways involved that lead to vaccine-mediated protection. This study suggests that PBL are a suitable platform for initial screening of vaccine candidates, for evaluation of vaccine-induced immune responses, and a cheap alternative for potency testing to reduce animal use in aquaculture vaccine development.


Assuntos
Aquicultura/métodos , Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Expressão Gênica/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/imunologia , Aeromonas salmonicida/imunologia , Animais , Vacinas Bacterianas/administração & dosagem , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Técnicas In Vitro/métodos , Leucócitos/imunologia , Yersinia ruckeri/imunologia
20.
Mar Pollut Bull ; 146: 399-407, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426174

RESUMO

Finfish cage culture is the most predominant form of mariculture. The rapid expansion of fish cage culture systems has raised concerns about their environmental impact, such as nutrient release. In this study, for the first time, we estimated the release of nitrogen (N) and phosphorus (P) from fish cage culture in Daya Bay, southern China, by constructing N and P budget models based on a mass balance principle. In addition, the contribution and importance of nutrients from fish culture and other nutrient sources, including submarine groundwater discharge, benthic sediments, local rivers, and atmospheric deposition were assessed. The annual amount of N and P released from fish cage culture was 205.6 metric tons (hereafter tons) of N and 39.2 tons of P, including 142.7 tons of dissolved inorganic nitrogen (DIN) and 15.1 tons of dissolved inorganic phosphorus (DIP). Among the analyzed nutrient sources, the contributions of DIN and DIP from fish culture were 7.0% and 2.7%, respectively. For cages consuming conventional trash fish, 142 kg of N and 26 kg of P were released into the environment per ton of fish products, much higher than the values (72 kg N and 17.3 kg P) for cages using formulated feed. In fish culture, the dissolved nutrients were more N rich, but the particulate nutrients were more P rich. The ratio of cage-derived N and P was 21.1, higher than the ratio of coastal seawater (27.1), indicating that cage culture may also impact the local nutrient forms around farming regions. Oyster cultivation and harvest removed 126.3 tons of N and 35.1 tons of P from of the bay. Replacing trash fish with formulated feed and co-culturing of nutrient extractive species (e.g., bivalves, macroalgae) and deposit-feeding species (e.g., sea cucumber) in fish culture zones can be efficient nutrient mitigation strategies.


Assuntos
Aquicultura/métodos , Peixes , Nitrogênio/análise , Fósforo/análise , Ração Animal , Animais , Baías , China , Recuperação e Remediação Ambiental/métodos , Nutrientes , Ostreidae , Rios , Água do Mar/química , Poluentes Químicos da Água/análise
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