The decline of fisheries on the Madeira River,Brazil: The high cost of the hydroelectric dams in the Amazon Basin          下载免费PDF全文

Rangel E. Santos  Ricardo M. Pinto‐Coelho  Rogério Fonseca  Nadson R. Simões  Fabrício B. Zanchi 《Fisheries Management and Ecology》2018,25(5):380-391

Despite being considered beneficial by providing a clean and renewable source of energy, the construction of hydroelectric dams has extremely negative implications for Amazonian fisheries. This study investigated the impacts of the Santo Antônio and Jirau hydroelectric dams on the fishery stocks of the Madeira River. This investigation was based on fish catch data from the Z‐31 fishing colony, located in the municipality of Humaitá, in Amazonas State, Northern Brazil. Data were collected daily and provided information on the date of return from each trip, the fish species targeted, and the total catch (kg) between January 2002 and September 2017. The results indicated reductions of 39% in the mean annual catch and 34% in the mean monthly catches. These results highlight the high price paid by local fish communities for the development of hydroelectric power in the Amazon basin.  相似文献   

Loss of genetic variability in the captive stocks of tambaqui,Colossoma macropomum (Cuvier, 1818), at breeding centres in Brazil,and their divergence from wild populations          下载免费PDF全文

Jonas da Paz Aguiar  Paola Fabiana Fazzi Gomes  Igor Guerreiro Hamoy  Sidney Emanuel Batista dos Santos  Horacio Schneider  Iracilda Sampaio 《Aquaculture Research》2018,49(5):1914-1925

The loss of variability in farmed populations and the risks of interactions with wild populations support the need for the genetic monitoring of species farmed throughout the world. In Brazil, the tambaqui is the most widely farmed native fish species. Despite this, there are no data on the pedigree of the farmed stocks, and the potential for interactions with wild populations in the Amazon basin has raised concerns with regard to the genetic variability of these stocks. The present study analysed sequences of the mitochondrial Control Region and 12 microsatellites to characterize the genetic variability of seven historically important commercial tambaqui breeding centres located in four different regions of Brazil, and compared these sequences with those obtained from individuals collected from a wild population. High levels of genetic diversity were found in the wild population, whereas genetic diversity was reduced in both markers in most captive populations, except for the broodstock located near the Amazon River. High F_ST and D_EST indices were recorded between the wild population and most of the captive stocks analysed. The drastic reduction in genetic diversity found in most captive stocks and the difference between these stocks and the wild population may have been the result of the small size of the founding populations and the absence of breeding management. The renewal of the broodstocks and the application of breeding management techniques are recommended. In the Amazon region, in addition, the use of broodstocks that are genetically very different from local wild populations should be avoided.  相似文献   

The future of fish passage science,engineering, and practice          下载免费PDF全文

Ana T. Silva  Martyn C. Lucas  Theodore Castro‐Santos  Christos Katopodis  Lee J. Baumgartner  Jason D. Thiem  Kim Aarestrup  Paulo S. Pompeu  Gordon C. O'Brien  Douglas C. Braun  Nicholas J. Burnett  David Z. Zhu  Hans‐Petter Fjeldstad  Torbjørn Forseth  Nallamuthu Rajaratnam  John G. Williams  Steven J. Cooke 《Fish and Fisheries》2018,19(2):340-362

Much effort has been devoted to developing, constructing and refining fish passage facilities to enable target species to pass barriers on fluvial systems, and yet, fishway science, engineering and practice remain imperfect. In this review, 17 experts from different fish passage research fields (i.e., biology, ecology, physiology, ecohydraulics, engineering) and from different continents (i.e., North and South America, Europe, Africa, Australia) identified knowledge gaps and provided a roadmap for research priorities and technical developments. Once dominated by an engineering‐focused approach, fishway science today involves a wide range of disciplines from fish behaviour to socioeconomics to complex modelling of passage prioritization options in river networks. River barrier impacts on fish migration and dispersal are currently better understood than historically, but basic ecological knowledge underpinning the need for effective fish passage in many regions of the world, including in biodiversity hotspots (e.g., equatorial Africa, South‐East Asia), remains largely unknown. Designing efficient fishways, with minimal passage delay and post‐passage impacts, requires adaptive management and continued innovation. While the use of fishways in river restoration demands a transition towards fish passage at the community scale, advances in selective fishways are also needed to manage invasive fish colonization. Because of the erroneous view in some literature and communities of practice that fish passage is largely a proven technology, improved international collaboration, information sharing, method standardization and multidisciplinary training are needed. Further development of regional expertise is needed in South America, Asia and Africa where hydropower dams are currently being planned and constructed.  相似文献   

Description and molecular phylogeny of one new and one known needle nematode of the genus <Emphasis Type="Italic">Paralongidorus</Emphasis> (Nematoda: Longidoridae) from grapevine in Portugal using integrative approach     

Carlos Gutiérrez-Gutiérrez  Manuel Mota  Pablo Castillo  Margarida Teixeira Santos  Juan E. Palomares-Rius 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(1):155-172

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Soybean seed coat chitinase as a defense protein against the stored product pest Callosobruchus maculatus          下载免费PDF全文

Nadia CM Silva  Jamile G Conceição  Kayan Eudorico Ventury  Leonardo FR De Sá  Eduardo AG Oliveira  Izabela S Santos  Valdirene M Gomes  Monique N Costa  Andre TS Ferreira  Jonas Perales  Jose Xavier‐Filho  Kátia VS Fernandes  Antonia EA Oliveira 《Pest management science》2018,74(6):1449-1456

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Involvement of cholinergic and adenosinergic systems on the branchial immune response of experimentally infected silver catfish with Streptococcus agalactiae          下载免费PDF全文

M D Baldissera  C F Souza  P H Doleski  K L S Moreira  M L da Veiga  M I U M da Rocha  R C V Santos  B Baldisserotto 《Journal of fish diseases》2018,41(1):27-32

It has been recognized that the cholinergic and adenosinergic systems have an essential role in immune and inflammatory responses during bacterial fish pathogens, such as the enzymes acetylcholinesterase (AChE) and adenosine deaminase (ADA), which are responsible for catalysis of the anti‐inflammatory molecules acetylcholine (ACh) and adenosine (Ado) respectively. Thus, the aim of this study was to investigate the involvement of the cholinergic and adenosinergic systems on the immune response and inflammatory process in gills of experimentally infected Rhamdia quelen with Streptococcus agalactiae. Acetylcholinesterase activity decreased, while ACh levels increased in gills of infected animals compared to uninfected animals. On the other hand, a significant increase in ADA activity with a concomitant decrease in Ado levels was observed in infected animals compared to uninfected animals. Based on this evidence, we concluded that infection by S. agalactiae in silver catfish alters the cholinergic and adenosinergic systems, suggesting the involvement of AChE and ADA activities on immune and inflammatory responses, regulating the ACh and Ado levels. In summary, the downregulation of AChE activity exerts an anti‐inflammatory profile in an attempt to reduce or prevent the tissue damage, while the upregulation of ADA activity exerts a pro‐inflammatory profile, contributing to disease pathophysiology.  相似文献   

Aflatoxin B<Subscript>1</Subscript> (AFB<Subscript>1</Subscript>) reduces growth performance,physiological response,and disease resistance in Tra catfish (<Emphasis Type="Italic">Pangasius hypophthalmus</Emphasis>)     

Rui A. Gonçalves  Tu Do Cam  Nguyen Nhu Tri  Gonçalo A. Santos  Pedro Encarnação  Le Thanh Hung 《Aquaculture International》2018,26(3):921-936

Triplicate groups of one hundred Tra catfish (8 g?±?0.2) were fed seven test diets containing increasing levels of AFB₁ (0, 50, 100, 250, 500, and 1000 μg AFB₁ kg^?1). Additionally Mycofix® Secure was added at 1.5% to one diet containing 500 μg AFB₁ kg^?1. Results showed that Tra catfish are sensitive to AFB₁. Reduction in weight gain (P?<?0.05) was observed for fish fed 50 μg AFB₁ kg^?1 and declined further with increasing levels of AFB₁ in the diets. Fish fed diets contaminated with 500 and 1000 μg AFB₁ kg^?1 showed increased (P?>?0.05) hepatosomatic index (HIS), while an increase in adipose somatic index (ASI) was observed in fish fed 50 μg AFB₁ kg^?1 and above when compared to the control and Mycofix® diets. After 12 weeks, blood serum analysis revealed higher alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in fish fed the 50, 100, and 250 μg AFB₁ kg^?1 suggesting occurrence of liver damage. Disease resistance of fish exposed to Edwardsiella ictaluri was also compromised by the presence of AFB₁ in the feed and was directly related to the contamination level. Seven days after Edwardsiella ictaluri exposure, survival rates were 50, 41.7, 31.7, and 8.3% for fish fed control, 50, 100, and 250 μg AFB₁ kg^?1, respectively. This trial shows that AFB₁ at a level of 50 μg AFB₁ kg^?1 and above can affect fish performance and disease resistance. Application of an effective mycotoxin management in the feed seems to be useful to prevent the negative effects of AFB₁.  相似文献   

Cross‐effects of dietary probiotic supplementation and rearing temperature on growth performance,digestive enzyme activities,cumulative mortality and innate immune response in seabass (Dicentrarchus labrax)          下载免费PDF全文

L.F. Pereira  M.J. Peixoto  P. Carvalho  K. Sansuwan  G.A. Santos  J.F.M. Gonçalves  R.O.A. Ozório 《Aquaculture Nutrition》2018,24(1):453-460

Probiotic influence on fish immune response and digestive capacity is extensively discussed in aquaculture. In this experiment, a feeding trial was carried out for 100 days to evaluate the cross‐effects of probiotic supplementation and rearing temperature (17, 20 and 23°C) in juvenile seabass (Dicentrarchus labrax). The experimental diet was supplemented with a commercial probiotic blend (Biomin AquaStar Growout) at 3 g/kg diet (5.23 × 10⁸ CFU/kg diet), and tested against a non‐supplemented diet (control). Growth performance and innate immune responses were analysed at 70 and 100 days of feeding, whereas digestive enzyme activities were determined at 100 days of feeding. At the end of the feeding trial, fish were subjected to a handling stress and cumulative mortality was recorded. Digestive enzyme activities were influenced by temperature, with α‐amylase and lipase activities peaking at the higher temperature (23°C) and trypsin at the lower temperature (17°C). Immune parameters showed a significant temperature versus feeding duration effect, with complement system (ACH50) and peroxidase peaking at 70 and 100 days of feeding, respectively. Poststress cumulative mortality was higher at the lowest temperature (17°C), especially in fish fed the control diet. In conclusion, water temperature was the main variable affecting the studied parameters, whereas the dietary probiotic supplementation had influence on the chymotrypsin activity and survival rate in seabass reared at 17°C.  相似文献   

First feeding of diploid and triploid yellowtail tetra Astyanax altiparanae: An initial stage for application in laboratory studies          下载免费PDF全文

Rafaela Manchin Bertolini  José Augusto Senhorini  Nivaldo Ferreira do Nascimento  Matheus Pereira‐Santos  Laura Satiko Okada Nakaghi  Wellington Adriano Moreira Peres  Regiane Cristina da Silva  George Shigueki Yasui 《Aquaculture Research》2018,49(1):68-74

In this study, the aim was to establish a protocol for first feeding of diploid and triploid yellowtail tetra Astyanax altiparanae in laboratory conditions. The fry were fed with five different diets: (i) Artemia franciscana nauplii, (ii) plankton, (iii) dry food, (iv) Artemia franciscana nauplii + plankton, and (v) Artemia nauplii + plankton + dry food. Additionally, the growth and survival rates of diploid and triploid individuals were also evaluated. On day 10, the length of the fish between the treatments differed significantly (p = .0001) and ranged from 4.07 ± 0.06 mm (dry food) to 8.50 ± 0.64 mm (plankton + Artemia). The sizes of the fish increased with time, except for the fish fed with dry food. The survival rates were similar for the fish fed with the four diets and ranged from 80.7 ± 5.4% (dry food + plankton + Artemia to 92.0 ± 1.6% (plankton + Artemia), but differed from the fish fed with dry food (17.7 ± 5.8%, p = .0017). Diploids and triploids did not present differences on day 0 (p = .2252) and on day 10 (p = .4844) when the fish presented 6.77 ± 0.25 mm and 6.54 ± 0.15 mm respectively. Survival of diploids (87.3 ± 5.13%) and triploids (74.67 ± 2.30%) were also similar (p = .0285). These data are innovative and useful for establishing protocols for this species in both academic and applied sciences.  相似文献   

Lippia alba (Verbenaceae) hydrolate as sedative of tambaqui (Colossoma macropomum) juveniles in simulated transport conditions          下载免费PDF全文

Hugo Napoleão Pereira da Silva  Elen Monique de Oliveira Sousa  Janna Laely dos Santos Maia  Mônica Tatiane Lima Pinheiro  Soraia Valeria de Oliveira Coelho Lameirão  Rosa Helena Veras Mourão  José Guilherme Soares Maia  Bernardo Baldisserotto  Lenise Vargas Flores da Silva 《Aquaculture Research》2018,49(1):128-134

Lippia alba hydrolate (LAH) is produced as a secondary product in essential oil extraction. The objective of this study was to evaluate the use of LAH in a simulation of the transport of tambaqui (Colossoma macropomum) juveniles. A series of 17 hr simulations were performed using load densities of 30, 60 and 90 juveniles per L and four LAH concentrations of 0.4%, 1%, 2% and 5%, with a control of just water. Fish survival, temperature, dissolved oxygen, conductivity, pH, ammonia excretion, alkalinity water hardness and net Na⁺, K⁺, Cl^‐ fluxes, were all evaluated before and after the transport simulations. Mucous cell densities in the gills were also determined microscopically, post simulation. The results showed that addition of 5% LAH achieved better survival during the simulation than the water control. Dissolved oxygen was significantly lower with an increased load density. Also, conductivity, NH₄ excretion and net ionic fluxes (K⁺ and Cl^?) were lower with 5% LAH, although mainly where higher load densities were tested. Mucous cell density was lower in LAH concentrations of 2% and 5%, again with higher load densities. In view of these findings, it is suggested that 5% LAH is an effective sedative for use in the transport of tambaqui, mainly with high load densities. This work is the first study of LAH and highlights its potential applications in aquaculture management.  相似文献