The energetic costs of being in stressful conditions require the involvement of hormones associated with metabolic support, which may also influence immune function. The present work aimed to explore the links between tryptophan nutrition and metabolic responses in European seabass (Dicentrarchus labrax) held under space-confined conditions, and subsequently submitted to an immune challenge. To study that, two dietary treatments were evaluated, i.
View Article and Find Full Text PDFVaccination is an effective, cost-efficient method to preventing disease outbreaks. However, vaccine procedures can induce adverse reactions due to stress, increasing plasma cortisol in the short term. In this context, tryptophan may prove to be fundamental as it has been demonstrated to have various desirable neuroendocrine attributes in different fish species.
View Article and Find Full Text PDFWhere teleost fish are concerned, studies in tryptophan immunomodulation generally point to immunosuppressive properties, thus presenting a potential anti-inflammatory dietary strategy. The goal of the present work was to evaluate the effects of tryptophan dietary supplementation on immune and neuroendocrine responses of the European seabass, , undergoing chronic inflammation. Juvenile European seabass were intraperitoneally injected with either Freund's Incomplete Adjuvant (FIA, inflamed group) or a saline solution (control group).
View Article and Find Full Text PDFImmune nutrition is currently used to enhance fish health by incorporating functional ingredients into aquafeeds. This study aimed to investigate the connections between tryptophan nutrition and the network that regulates the communication pathways between neuroendocrine and immune systems in European seabass (Dicentrarchus labrax). When tryptophan was supplemented in the diet of unstressed fish, it induced changes in the hypothalamic-pituitary-interrenal axis response to stress.
View Article and Find Full Text PDFTurbot aquaculture production is an important economic activity in several countries around the world; nonetheless, the incidence of diseases, such furunculosis, caused by the etiological agent subsp. , is responsible for important losses to this industry worldwide. Given this perspective, this study aimed to evaluate early immune responses in turbot ( L.
View Article and Find Full Text PDFThe present work aimed to study the role of dietary tryptophan supplementation in modulating the European seabass () immune condition during stressful rearing conditions (i.e., 15 days exposure to high density), as well as the immune response to acute inflammation after intraperitoneal injection of a bacterial pathogen.
View Article and Find Full Text PDFStress-inducing husbandry and rearing conditions, bacterial infections or parasitic diseases may all lead to chronic inflammation. The immune response will then channel energy away from growth, reproduction and other important physiological processes, to fuel immune-related metabolic responses. The present study aims to unravel the mechanisms and contribute with new information on the molecular, cellular and humoral parameters of European seabass () undergoing chronic inflammation that can be used as health indicators for application in fish health management.
View Article and Find Full Text PDFAquaculture has been challenged to find alternative ingredients to develop innovative feed formulations that foster a sustainable future growth. Given the most recent trends in fish feed formulation on the use of alternative protein sources to decrease the dependency of fishmeal, it is fundamental to evaluate the implications of this new paradigm for fish health and welfare. This work intends to comprehensively review the impacts of alternative and novel dietary protein sources on fish gut microbiota and health, stress and immune responses, disease resistance, and antioxidant capacity.
View Article and Find Full Text PDFIn fish, as observed in mammals, any stressful event affects the immune system to a larger or shorter extent. The neuroendocrine-immune axis is a bi-directional network of mobile compounds and their receptors that are shared between both systems (neuroendocrine and immune) and that regulate their respective responses. However, how and to what extent immunity modulates the neuroendocrine system is not yet fully elucidated.
View Article and Find Full Text PDFCurrently, aquaculture production of rainbow trout () is a multibillion dollar industry; nevertheless, the development of this sector has not been exempt from pitfalls related to the recurrent presence of pathogens of bacterial origin. This is the case of , the etiologic agent of the infectious pathology known as Enteric Red Mouth Disease (ERM), causing serious economic losses that can be as high as 30-70% of production. Although several studies have been performed regarding pathogen features and virulence factors, more information is needed about the host defense mechanism activation after infection.
View Article and Find Full Text PDFSeveral amino acids (AA) are known to regulate key metabolic pathways that are crucial for immune responses. In particular, arginine (ARG) appears to have important roles regarding immune modulation since it is required for macrophage responses and lymphocyte development. Moreover, citrulline (CIT) is a precursor of arginine, and it was reported as an alternative to ARG for improving macrophage function in mammals.
View Article and Find Full Text PDFThe present study was designed to determine the modulatory effects of arginine and citrulline dietary supplementation on the immune condition and inflammatory response of European seabass, Dicentrarchus labrax. Four diets were manufactured: a control diet (CTRL) was formulated to meet the indispensable amino acids profile established for seabass. Based on this formulation, three other diets were supplemented with l-arginine at two different levels (0.
View Article and Find Full Text PDFIncreasing water CO, aquatic hypercapnia, leads to higher physiological pCO levels in fish, resulting in an acidosis and compensatory acid-base regulatory response. Senegalese sole is currently farmed in super-intensive recirculating water systems where significant accumulation of CO in the water may occur. Moreover, anthropogenic releases of CO into the atmosphere are linked to ocean acidification.
View Article and Find Full Text PDFEuropean aquaculture is an industry with a high sustainability profile contributing to the supply of safe seafood. However, several diseases can affect farmed fish and it is imperative to find alternatives for chemotherapeutic treatments when disease outbreaks occur. Maintenance of health through nutrition is well-establish in modern animal farming, and amino acids (AA) are promising candidates as functional additives to improve fish health.
View Article and Find Full Text PDFHigh rearing densities are typical conditions of both inland and onshore intensive aquaculture units. Despite obvious drawbacks, this strategy is nonetheless used to increase production profits. Such conditions inflict stress on fish, reducing their ability to cope with disease, bringing producers to adopt therapeutic strategies.
View Article and Find Full Text PDFMethionine presents a pivotal role in the regulation of many cellular events with crucial impact on the immune system, such as in processes involved in the control of inflammation and polyamines synthesis. Accordingly, the present study aimed to assess the modulatory effects of dietary methionine on the European seabass () immune status, inflammatory response and disease resistance to subsp. piscicida ().
View Article and Find Full Text PDFSenegalese sole Solea senegalensis is currently farmed in recirculation aquaculture systems that often involve water re-oxygenation, which in turn may cause acute or prolonged hyperoxia exposures. In order to understand the impact of acute hyperoxia on the fish immune system and peripheral tissues such as gills and gut, Senegalese sole juveniles (30.05 ± 1.
View Article and Find Full Text PDFTeleost innate immune system is a most developed and powerful system in which fish highly rely throughout their lives. Conditions in aquaculture farms are particularly prone to disease, thus, health and welfare ensuring strategies are an urgent call to which nutrition is gradually becoming a most regarded achievement tool. This study intended to evaluate different amino acids' effect on immune-related mechanisms as well as their potential as enhancers of European seabass, Dicentrarchus labrax, leucocyte functioning.
View Article and Find Full Text PDFMethionine and tryptophan appear to be fundamental in specific cellular pathways involved in the immune response mechanisms, including stimulation of T-regulatory cells by tryptophan metabolites or pro-inflammatory effects upon methionine supplementation. Thus, the aim of this study was to evaluate the immunomodulatory effect of these amino acids on the inflammatory and neuroendocrine responses in juveniles of European seabass, . To achieve this, goal fish were fed for 14 days methionine and tryptophan-supplemented diets (MET and TRP, respectively, 2× dietary requirement level) or a control diet meeting the amino acids requirement levels (CTRL).
View Article and Find Full Text PDFInclusion of prebiotics in aqua feeds, though a costly strategy, has increased as a means to improve growth. Still, its effects on health improvement are not fully disclosed. Regarding their immunestimulatory properties, research has focused on carbohydrates such as fructooligosaccharides and xylooligosaccharides demonstrating their modulatory effects on immune defences in higher vertebrates but few studies have been done on their impact on fish immunity.
View Article and Find Full Text PDFInfectious diseases and fish feeds management are probably the major expenses in the aquaculture business. Hence, it is a priority to define sustainable strategies which simultaneously avoid therapeutic procedures and reinforce fish immunity. Currently, one preferred approach is the use of immunostimulants which can be supplemented to the fish diets.
View Article and Find Full Text PDFAmino acids regulate key metabolic pathways important to immune responses and their nutritional supply may increase synthesis of immune-related proteins. The present study aimed to evaluate the effects of dietary supplementation of tryptophan and methionine on European seabass (Dicentrarchus labrax) cellular and humoral status. The immunomodulatory effects of tryptophan and methionine during an inflammatory insult was also evaluated after intraperitoneal injection with inactivated Photobacterium damselae subsp.
View Article and Find Full Text PDFThe present study aimed to evaluate the effects of two purified antinutrients, soy saponins and phytosterols, in an important species for Mediterranean aquaculture. For this purpose, gilthead seabream (Sparus aurata) were fed six experimental diets containing two levels of those antinutrients, alone or in combination, and a control diet, to apparent visual satiation under controlled conditions. Blood and head-kidney were collected at 7, 15 and 48 days following first feeding in order to assess immune parameters and the expression of immune-related genes.
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