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1.
Abstract— Hydrogen peroxide is being evaluated for its potential as a therapeutic compound for a variety of external disease organisms of fish. The value of hydrogen peroxide as a therapeutic compound for use in walleye Stizustedion vitreum culture has been questioned due to the high sensitivity (i.e., high mortality) of walleyes to this compound. We conducted bioassays and histopathological studies to determine if exposure of walleye to hydrogen peroxide bath treatments would result in increased tolerance to subsequent exposure. Test fish exhibited increased tolerance to hydrogen peroxide after initial exposures. This phenomenon of increased tolerance of walleyes to hydrogen peroxide may be of value in the development of management strategies for the successful treatment of fish diseases.  相似文献   

2.
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3.
Recent research has revealed surprisingly important connections between animals’ microbiome and social behaviour. Social interactions can affect the composition and function of the microbiome; conversely, the microbiome affects social communication by influencing the hosts’ central nervous system and peripheral chemical communication. These discoveries set the stage for novel research focusing on the evolution and physiology of animal social behaviour in relation to microbial transmission strategies. Here, we discuss the emerging roles of teleost fish models and their potential for advancing research fields, linked to sociality and microbial regulation. We argue that fish models, such as the zebrafish (Danio rerio, Cyprinidae), sticklebacks (?Gasterosteidae), guppies (Poeciliidae) and cleaner–client dyads (e.g., obligate cleaner fish from the Labridae and Gobiidae families and their visiting clientele), will provide valuable insights into the roles of microbiome in shaping social behaviour and vice versa, while also being of direct relevance to the food and ornamental fish trades. The diversity of fish behaviour warrants more interdisciplinary research, including microbiome studies, which should have a strong ecological (field‐derived) approach, together with laboratory‐based cognitive and neurobiological experimentation. The implications of such integrated approaches may be of translational relevance, opening new avenues for future investigation using fish models.  相似文献   

4.
The present review presents data on fish requirement for B vitamins and describes their mechanism of action. Both general deficiency symptoms such as reduced growth and appetite, and more specific deficiency signs, for example abnormal swimming activity due to thiamine deficiency, are included. The rationale is to elucidate the need to establish B vitamin recommendations for fish fed practical diets where the major part consists of plant ingredients. Most requirement studies referred to were performed with semi‐purified diets with relatively low growth rate compared to the growth potential of the fish obtained with practical diets. Further, when giving salmon a plant‐based diet (70% plant ingredients), substantial lowered growth was obtained even when the diet was added vitamins according to the newest established requirements. New recommendations for B vitamin addition in plant‐based diets are therefore urgent. Few requirement studies exist and often with lack of dose–response data. For riboflavin and biotin, this review includes a meta‐analysis to support earlier requirement estimates. Too few data existed on the others to perform any meta‐analyses that made sense. Based on literature data, meta‐analyses, new experiments utilizing dose–response designs and identification of metabolic biomarkers, this review suggests new B vitamin recommendations for fish fed plant‐based diets.  相似文献   

5.
As increasing amounts of novel raw materials are used in aquafeed production, it is important to measure their quality against existing ingredients and their effects upon production strategies. A first step to achieving this goal begins with an improved understanding of the underlying growth potential of each farmed species across a range of dietary ingredients and farming practices. Species‐specific physiological limitations and metabolic effects of both single chemicals and complex chemical matrixes are factors to be considered in producing robust fish and a healthy aquaculture sector. The industry must also consider ethical, environmental and economic issues and optimize feed management practices. This review summarizes current knowledge on European sea bass (Dicentrarchus labrax) nutritional requirements, presents current feed management practices for this species, gives insights on a secure framework for using plant ingredients in exchange for traditional marine raw materials and outlines its growth potential through a meta‐analysis of the best‐performance results available in peer‐reviewed scientific publications for this species. As the best‐performing fish were mostly those fed high fish meal fish oil control diets, the summarized results have the potential to be used as a quality control for benchmarking future scientific research in this fish species.  相似文献   

6.
Fish can be the recipients of numerous injuries that are potentially deleterious to aquacultural production performance and welfare. This review will employ a systematic approach that classifies injuries in relation to specific anatomical areas of the fish and will evaluate the effects of injury upon production and welfare. The selected areas include the (1) mouth, (2) eye, (3) epidermis and (4) fins. These areas cover a large number of external anatomical features that can be injured during aquacultural procedures and husbandry practices. In particular, these injuries can be diagnosed on live fish, in a farm environment. For each anatomical feature, this review addresses (a) its structure and function and (b) defines key injuries that can affect the fish from a production and a welfare perspective. Particular attention is then given to (c) defining known and potential aquacultural risk factors before (d) identifying and outlining potential short- and long-term farming practices and mitigation strategies to reduce the incidence and prevalence of these injuries. The review then concludes with an analysis of potential synergies between risk factors the type of injury, in addition to identifying potential synergies in mitigation strategies. The paper covers both aquaculture and capture-based aquaculture.  相似文献   

7.
Salmonid fish viruses, such as infectious haematopoietic necrosis virus (IHNV), are responsible for serious losses in the rainbow trout and salmon‐farming industries, and they have been the subject of intense research in the field of aquaculture. Thus, the aim of this work is to study the antiviral effect of milk‐derived proteins as bovine caseins or casein‐derived peptides at different stages during the course of IHNV infection. The results indicate that the 3‐h fraction of casein and αS2‐casein hydrolysates reduced the yield of infectious IHNV in a dose‐dependent manner and impaired the production of IHNV‐specific antigens. Hydrolysates of total casein and αS2‐casein target the initial and later stages of viral infection, as demonstrated by the reduction in the infective titre observed throughout multiple stages and cycles. In vivo, more than 50% protection was observed in the casein‐treated fish, and the kidney sections exhibited none of the histopathological characteristics of IHNV infection. The active fractions from casein were identified, as well as one of the individual IHNV‐inhibiting peptides. Further studies will be required to determine which other peptides possess this activity. These findings provide a basis for future investigations on the efficacy of these compounds in treating other viral diseases in farmed fish and to elucidate the underlying molecular mechanisms of action. However, the present results provide convincing evidence in support of a role for several milk casein fractions as suitable candidates to prevent and treat some fish viral infections.  相似文献   

8.
It has been demonstrated that large quantities of ammonia may be released into the water of a fish pond following the collapse of an algal bloom. Some blue-green algae are thought to release toxins. This paper puts forward another explanation for this occurrence. A review of the disease known as Infectious Dropsy of Carp (IDC) based on the findings of this paper shows it to be caused by ammonia. Various methods to counteract this disease are described. Particular emphasis is placed on the policy concerning the addition of fertilizers. It is shown that dense blooms of nitrogen-fixing algae can be controlled by manipulation of the nitrogen: phosphorus balance of ponds. Determination of the aetiology of carp dropsy will probably lead to a better understanding of other diseases of fish which are manifested by similar symptoms. The disease of trout known as Viral Haemorrhagic Septicaemia (VHS) is discussed in this context. For clarification it is proposed that infectious dropsy of carp be renamed Environmental Ammonotelic Syndrome (EAS).  相似文献   

9.
Over the years, aquaculture has shown increasing development in terms of production. However, due to intensive farming practices, infectious diseases represent the main problem in fish farms, causing heavy economic losses. The use of antibiotics for controlling diseases is widely criticized for its negative impact, including selection of antibiotic‐resistant bacterial strains, immunosuppression, environmental pollution and accumulation of chemical residues in fish tissues. On the other hand, though vaccination is the most effective prophylactic method of preventing disease outbreaks, the development of effective formulations is often hindered by high production costs and the antigenic heterogeneity of the microbial strains. Recently, there has been increased interest in the possibility of using medicinal herbs as immunostimulants, capable of enhancing immune responses and disease resistance of cultured fish. Plant‐derived products seem to represent a promising source of bioactive molecules, being at the same time readily available, inexpensive and biocompatible. The aim of this article is to provide an overview of recent research dealing with the use of medicinal plants in aquaculture. Special attention is given to the information about the effects of plant extracts/products on fish growth, haematological profiles, immune responses and resistance to infectious diseases.  相似文献   

10.
In many countries, infectious diseases are a considerable threat to aquaculture. The pathogenicity of micro‐organisms that infect aquaculture systems is closely related to the release of virulence factors and the formation of biofilms, both of which are regulated by quorum sensing (QS). Thus, QS disruption is a potential strategy for preventing disease in aquaculture systems. QS inhibitors (QSIs) not only inhibit the expression of virulence‐associated genes but also attenuate the virulence of aquaculture pathogens. In this review, we discuss QS systems in important aquaculture pathogens and focus on the relationship between QS mechanisms and bacterial virulence in aquaculture. We further elucidate QS disruption strategies for targeting aquaculture pathogens. Four main types of QSIs that target aquaculture pathogens are discussed based on their mechanisms of action.  相似文献   

11.
Originally developed to assess the relative abundance of ≥1+ fishes in large rivers, point abundance sampling by electrofishing (PASE) was adapted for 0+ fishes in the mid‐1980s. Being both economical and widely applicable, PASE for 0+ fish has become a commonly used sampling approach in Europe, but its use for estimating 0+ fish density and species richness has attracted particular concern because of size and species selectivity. As such, this review is both timely and necessary. It summarizes the development of PASE and evaluates its various applications: studies of 0+ fish community composition, relative abundance and density, species richness (S), population size structure, larval and juvenile growth dynamics, microhabitat use, diel dynamics of species–species and species–microhabitat interactions, and the analysis of data emanating from PASE databases. The use and potential misuse of replicate sampling in estimates of S are examined, with PASE data from various European rivers re‐analysed to assess geographical patterns in 0+ fish S. Comparisons of PASE and other approaches for estimating 0+ fish density and species richness have all demonstrated PASE to be cost‐effective and relatively reliable, but sampling accuracy and precision do decrease as fishes enter the juvenile period of development.  相似文献   

12.
Abstract Although neutral molecular markers have long been important tools for describing genetic variation in threatened fish species, many of the most critical questions in conservation relate more to quantitative genetic variation than to neutral markers. Quantitative genetic studies are typically expensive and time-consuming to conduct, especially in some of the long-lived vertebrates of conservation concern. The present review of recent literature in fish conservation genetics examines the traditional role of molecular studies in describing conservation units and providing indirect inference about local adaptation and adaptive potential. Of special interest are approaches that use a combination of molecular and quantitative genetic methods. Such studies are likely to provide important new insights into many conservation-related problems. The review also explores how increasing interest in non-neutral molecular markers is contributing to our understanding of the geographic scale and evolutionary importance of local adaptation in threatened populations. It is increasingly clear that advanced genetic technologies for the exploration of neutral and non-neutral molecular variation are leading to a fundamental shift in the way complex phenotypic traits are studied. This new synthesis of methods will have dramatic implications for fish conservation genetics and biology in general.  相似文献   

13.
Oxidative stress results from an imbalance between the production of reactive oxygen species and the antioxidants defences, in favour of the former. In recent years, the association between oxidative processes, environmental change and life histories has received much attention. However, most studies have focused on avian and mammalian taxonomic groups, with less attention given to fish, despite their ecological and socio‐economic relevance. Here we present a review of the extrinsic and intrinsic factors that influence oxidative processes in fish, using a comparative and evolutionary approach. We demonstrate that oxidative stress plays a key role in shaping fish's responses to environmental change as well as life history strategies. We focus on representative examples to compare and contrast how levels of oxidative stress respond to changes in temperature, salinity and oxygen availability. Furthermore, we describe how emerging threats (i.e. pollution) affect oxidative stress parameters in fish. Oxidative stress indicators are increasingly being used as biomarkers to understand the mechanisms of various human‐induced stressors, but also to understand the physiological consequences of how animals are distributed in space and time and influenced by different life stages. Despite the expansion of the field of ecological oxidative stress, we are only beginning to understand the complex ways in which oxidative stress may interact with both extrinsic and intrinsic factors in fish. We conclude with a research agenda for oxidative research on fish and note that there is need for further research particularly in the area of life history strategies and ecological implications of oxidative status, as this type of research has the potential to help us understand patterns and dynamics relevant to fish conservation.  相似文献   

14.
Dredging can have significant impacts on aquatic environments, but the direct effects on fish have not been critically evaluated. Here, a meta‐analysis following a conservative approach is used to understand how dredging‐related stressors, including suspended sediment, contaminated sediment, hydraulic entrainment and underwater noise, directly influence the effect size and the response elicited in fish across all aquatic ecosystems and all life‐history stages. This is followed by an in‐depth review summarizing the effects of each dredging‐related stressor on fish. Across all dredging‐related stressors, studies that reported fish mortality had significantly higher effect sizes than those that describe physiological responses, although indicators of dredge impacts should endeavour to detect effects before excessive mortality occurs. Studies examining the effects of contaminated sediment also had significantly higher effect sizes than studies on clean sediment alone or noise, suggesting additive or synergistic impacts from dredging‐related stressors. The early life stages such as eggs and larvae were most likely to suffer lethal impacts, while behavioural effects were more likely to occur in adult catadromous fishes. Both suspended sediment concentration and duration of exposure greatly influenced the type of fish response observed, with both higher concentrations and longer exposure durations associated with fish mortality. The review highlights the need for in situ studies on the effects of dredging on fish which consider the interactive effects of multiple dredging‐related stressors and their impact on sensitive species of ecological and fisheries value. This information will improve the management of dredging projects and ultimately minimize their impacts on fish.  相似文献   

15.
Little research has been done in optimizing the nitrogenous fraction of the fish diets in order to minimize welfare problems. The purpose of this review is to give an overview on how amino acid (AA) metabolism may be affected when fish are under stress and the possible effects on fish welfare when sub-optimal dietary nitrogen formulations are used to feed fish. In addition, it intends to evaluate the current possibilities, and future prospects, of using improved dietary nitrogen formulations to help fish coping with predictable stressful periods. Both metabolomic and genomic evidence show that stressful husbandry conditions affect AA metabolism in fish and may bring an increase in the requirement of indispensable AA. Supplementation in arginine and leucine, but also eventually in lysine, methionine, threonine and glutamine, may have an important role in enhancing the innate immune system. Tryptophan, as precursor for serotonin, modulates aggressive behaviour and feed intake in fish. Bioactive peptides may bring important advances in immunocompetence, disease control and other aspects of welfare of cultured fish. Fishmeal replacement may reduce immune competence, and the full nutritional potential of plant-protein ingredients is attained only after the removal or inactivation of some antinutritional factors. This review shows that AA metabolism is affected when fish are under stress, and this together with sub-optimal dietary nitrogen formulations may affect fish welfare. Furthermore, improved dietary nitrogen formulations may help fish coping with predictable stressful events.  相似文献   

16.
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17.
集约化养殖条件下鱼类营养代谢性疾病频发,如何防治是目前亟待解决的问题。寻找导致营养代谢性疾病的关键基因,并研究其功能及作用机制是目前研究的热点。高通量测序技术为研究者提供了海量的基因信息,如何有效的挖掘、分析和存储数据并用于疾病的防治显得尤为重要。目前,鱼类营养代谢性疾病相关基因数据库的开发和利用仍处于研究初期。为了合理高效地利用现有的组学数据信息,本研究系统地调研了鱼类代谢性疾病相关数据库,明晰了NCBI数据库中265种鱼类的基因组大小和64种鱼类的染色体数目,获取了Ensembl数据库中17个目58种鱼类的基因组数据,收集了KEGG数据库中41种鱼类的糖类、脂类和蛋白质代谢相关基因。本文可为鱼类营养代谢性疾病基因数据库的研发提供数据支撑,并为鱼类营养代谢性疾病的治疗和预防奠定坚实的基础。  相似文献   

18.

Globally, aquaculture has faced serious economic problems due to bacterial, viral, and various other infectious diseases of different origins. Even though such diseases are being detected and simultaneously treated with several therapeutic and prophylactic methods, the broad-spectrum activity of vaccines plays a vital role as a preventive measure in aquaculture. However, treatments like use of antibiotics and probiotics seem to be less effective when new mutant strains develop and disease causing pathogens become resistant to commonly used antibiotics. Therefore, vaccines developed by using recent advanced molecular techniques can be considered as an effective way of treating disease causing pathogens in aquatic organisms. The present review emphasizes on the current advances in technology and future outlook with reference to different types of vaccines used in the aquaculture industries. Beginning with traditional killed/inactivated and live attenuated vaccines, this work culminates in the review of modern new generation ones including recombinant, synthetic peptides, mucosal and DNA, subunit, nanoparticle-based and plant-based edible vaccines, reverse vaccinology, and monovalent and polyvalent vaccines.

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19.
Recreational angling has been implicated in population declines of some marine and freshwater fish, but this activity is rarely considered as a threat or even halted when endangered species are targeted. Indeed, in some cases, anglers are drawn to fish for rare or endangered species. Conservation‐oriented behaviours such as catch‐and‐release are often practiced voluntarily due to the ethics of anglers, yet even in these cases, some fishing mortality occurs. Nonetheless, there are many indirect conservation benefits associated with recreational angling. Here, we present a series of case‐studies and consider whether catch‐and‐release angling for endangered fish is a conservation problem or a conservation action. If recreational angling activities contribute to population‐level consequences that are contrary to recovery strategies, then angling for endangered species would seem to be a poor option. However, as revealed by several case‐studies, there is much evidence that anglers are vocal and effective proponents of fish and habitat conservation, and for endangered species, they are often the only voice when other stakeholders are not engaged. Anglers may contribute directly to conservation actions via user fees (e.g. licences), philanthropic donations or by volunteering in research, education and restoration activities. However, it is important to quantify post‐release mortality as well as understand the full suite of factors influencing a given population or species to know the potential risks. A risk assessment approach outlined in the paper may be used by managers to determine when the benefits of angling for endangered species outweigh the risks.  相似文献   

20.
Adoption of the ecosystem approach to fisheries management relies on recognition of the link between fish and other components of the ecosystem, namely their physical and biological habitat. However, identifying the habitat requirements of marine fishes and hence determining their distribution in space and time is scientifically complex. We analysed the methodologies and findings of research on temperate, demersal fish habitat requirements to highlight the main developments in this field and to identify potential shortfalls. Many studies were undertaken over large spatial scales (≥100s km2) and these generally correlated abundances of fish to abiotic variables. Biological variables were accounted for less often. Small spatial scale (≤m2), experimental studies were comparatively sparse and commonly focused on biotic variables. Whilst the number of studies focusing on abiotic variables increased with increasing spatial scale, the proportion of studies finding significant relationships between habitat and fish distribution remained constant. This mismatch indicates there is no justification for the tendency to analyse abiotic habitat variables at large spatial scales. Innovative modelling techniques and habitat mapping technologies are developing rapidly, providing new insights at the larger spatial scales. However, there is a clear need for a reduction in study scale, or increase in resolution additional to the integration of biotic variables. We argue that development of sound predictive science in the field of demersal fish habitat determination is reliant on a change in focus along these lines. This is especially important if spatial management strategies, such as Marine Protected Areas (MPA) or No Take Zones (NTZ), are to be used in future ecosystem‐based approaches to fisheries management.  相似文献   

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