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[ES] Los estudios sobre nutrición lipídica en piscicultura marina se han centrado en el suministro de ácidos grasos esenciales (AGE) en niveles altos para cumplir con los requisitos de supervivencia, crecimiento y desarrollo de los peces. Sin embargo, los ácidos grasos poliinsaturados de cadena muy larga (VLC-PUFA, más de 24 C) prácticamente no han sido explorados en el escenario de la acuicultura. Los VLC-PUFA, aunque presentes en muy poca cantidad, podrían ser fundamentales para el correcto desarrollo y funcionalidad de tejidos como la retina, el cerebro o las gónadas. El objetivo de este trabajo es contrastar a nivel interespecífico el patrón de expresión de los genes que codifican para las enzimas limitantes durante el proceso de biosíntesis de LC-PUFA (Elovl5, Fads2) y VLC-PUFA (Elovl4a, Elovl4b) analizando su regulación nutricional en postlarvas de S.aurata y S.senegalensis. Este proceso se ha estudiado en respuesta a una situación variable de biodisponibilidad de LC-PUFA, mediante el uso de micro-piensos inertes en cuya composición se ha variado el porcentaje de aceite de pescado (FO) en 33, 50 y 100%. Los resultados obtenidos proporcionan una visión integral de la regulación nutricional de estos genes en respuesta al contenido en aceite de pescado presente en la dieta. Todo ello, teniendo en cuenta las particularidades existentes en el mecanismo biosintético de PUFA asociado a cada especie. Además se resaltan las diferencias de expresión en función del tejido analizado., [EN] Studies on lipid nutrition in marine fish farming have focused on supplying essential fatty acids (EFA) at high levels to meet requirements for survival, growth and development of fish. However, very long chain polyunsaturated fatty acids (VLC-PUFA, more than 24 C) have been practically unexplored within the aquaculture scenario. VLC-PUFA, although present in very little amount, could be pivotal for the correct development and functionality of tissues like retina, brain and gonads. The aim of this work is to contrast the interspecific expression pattern of the genes encoding for the limiting enzymes in the biosynthesis of LC-PUFA (Elovl5, Fads2) and VLC-PUFA (Elovl4a, Elovl4b), analyzing their nutritional regulation, in postlarvae of S. aurata and S. senegalensis. This process is assessed in response to a variable situation of bioavailability of LC-PUFA, through the use of inert micro-feeds with different content (33, 50 and 100 %) of fish oil (FO). The results provide an integral vision of the nutritional regulation of these genes in response to the FO content present in the diet, depending on the particular PUFA biosynthetic mechanism of each species. Moreover, the differences as a function of the analyzed tissue are revealed.

Elongation of very long-chain fatty acids 4 (Elovl4) is a critical enzyme in the biosynthesis of long-chain and very long-chain polyunsaturated fatty acids (LC- and VLC-PUFAs) in animals. So far, very little is known about the molecular function of Elovl4 in biosynthetic process, especially in fish. In this study, two elovl4 paralogs (elovl4b1 and elovl4b2) were successfully cloned from rainbow trout (Oncorhynchus mykiss). The full-length cDNAs of elovl4b1 and elovl4b2 were shown to comprise 1896 bp and 2227 bp, respectively, and both contained 921 bp open reading frames (ORFs), encoded 306 amino acids in high homology. Heterologous expression in yeast showed that rainbow trout Elovl4b1 and Elovl4b2 proteins are able to effectively convert C18-22 polyunsaturated fatty acids (PUFAs) to the polyenoic products up to C32 or C36. Especially, compared with Elovl4b2, Elovl4b1 had much higher efficiency for converting 20:5n-3 and 22:5n-3 to 24:5n-3. Tissue distribution analysis revealed that rainbow trout elovl4b were widely transcribed in various tissues with the highest level in eye, brain and gill. Feeding experiment was conducted with three groups of rainbow trout fed diets with either fish oil (FO) or 100% of the FO replaced by soybean oil (SO) and linseeds oil (LO). Compared to fish fed the diet with FO, elovl4b was significantly up-regulated in the liver of fish fed the diet with SO and in the entire intestine of fish fed the diet with LO, which suggested that elovl4b expression is regulated by dietary lipid sources. These results may contribute to better understand the LC-PUFAs and VLC-PUFAs biosynthetic pathway and the regulation mechanism in rainbow trout.

The regulation of lipogenesis and lipolysis mechanisms related to consumption of lipid has not been studied in swimming crab. The aims of present study were to evaluate the effects of dietary lipid levels on growth, enzymes activities, and expression of genes of lipid metabolism in hepatopancreas of juvenile swimming crab. Three isonitrogenous diets were formulated to contain crude lipid levels at 5.8 %, 9.9 % and 15.1 %, respectively. Crabs fed the diet containing 15.1 % lipid had significantly lower weight gain, specific growth rate and survival, and higher feed conversion ratio than those fed the 5.8 % and 9.9 % lipid diets. Crabs fed 5.8 % lipid had lower malondialdehyde concentrations in the hemolymph and hepatopancreas than those fed the other diets. Highest glutathione peroxidase in hemolymph and superoxide dismutase in hepatopancreas were observed in crabs fed 5.8 % lipid. The lowest fatty acid synthase and glucose 6-phosphate dehydrogenase activities in hepatopancreas were observed in crabs fed 15.1 % lipid, whereas crabs fed 5.8 % lipid had lower carnitine palmitoyltransferase-1 activity than those fed the other diets. Crabs fed 15.1 % lipid showed lower hepatopancreas expression of genes involved in LC-PUFA biosynthesis, lipoprotein clearance, fatty acid uptake, fatty acid oxidation, lipid anabolism and lipid catabolism than those fed the other diets, whereas expression of some genes of lipoprotein assembly and fatty acid oxidation were up-regulated compared with crabs fed 5.8 % lipid. Overall, high dietary lipid level can inhibit growth, reduce feed utilization and reduce antioxidant enzyme activities. Moreover, dietary lipid influenced enzyme activities and gene expression involved in lipid metabolism of juvenile swimming crab.

This work brings together the view of different specialists in the areas of larviculture, physiology, ecology, nutrition and animal health, regarding how to deal with the aquaculture farming of species with complex life cycles in a multidisciplinary way, using as models the octopus and the muricid C. concholepas, with the aim of reducing the gap between the experimental and the industrial culture of species that are relevant for the diversification of aquaculture, particularly in Chile. Although these species are similar in their difficulty to reach the terminal planktonic phase prior to juvenile, they differ in the bottlenecks they have to overcome to reach it. Relevant aspects of study to achieve juvenile production from early life stages rearing, whether for repopulation or for ongrowing, are as follows: (i) Replacement or supplementation of live diets with inert diets to achieve significant survival values over the first stages of life. (ii) Physiological approaches to establish cultivation conditions evaluating the individual responses to several rearing conditions, specially the interaction between temperature, dissolved oxygen and acidity. Studies of urgent character due to the global warming scenario. (iii) Genomic studies associated with the effect of ontogenetic development, environment, health and nutrition on gene expression to understand, in an integrated way, the key processes for the development and growth of immature stages. (iv) Studies on the control of reproduction, the quality control of the ova, the genetic structure of reproductive populations and the characterization of diseases are also necessary to achieve efficient hatchery technologies.

Octopus vulgaris rearing/production presents several problems, mainly during the first stages, from eggs incubation to paralarvae rearing. In the last years, several research groups have been doing an effort to produce O. vulgaris in aquaculture focused on larval rearing phase, in order to solve these bottlenecks. In this sense, the present study aims to analyse the effect of different temperatures on common octopus embryonic development from one single female brood; as well as, larval viability and biomarkers of growth, physiological stress, antioxidant defences and neuronal activity (RNA/DNA, HSP70, GST and AChE, respectively). O. vulgaris eggs were incubated from stage XV to hatchlings at 19ºC and 22ºC, and then were maintained at room temperature (22±1ºC) for 14 days. Survival, specific growth rate, biomass and dry weight were measured over time. Samples from 0 and 14 days were taken in order to analyse biomarkers individually. Only HSP70 was analysed using a pool of 7-8 paralarvae. The results showed differences between temperatures in terms of survival and specific growth rate. RNA/DNA ratios and GST (0 and 14 days), and HSP70 (0, 7 and 14 days) showed differences between ages at different temperatures. No significant differences were found in AChE activity between groups (age and temperatures). The results point out at the RNA/DNA ratio, GST and HSP70 as sensitive biomarkers for growth, thermal stress and antioxidant defences in paralarvae. However, growth and temperature did not alter the neurotransmission system of the paralarvae.

[ES] El proyecto se compone de dos volúmenes residenciales diferentes, uno de tipología lineal en forma de “L” de altura variable y el otro con tipología de edificación aislada tipo torre. Situado en Benicalap, València. El objetivo principal consiste en el estudio y supervisión del seguimiento de obra del edificio de tipología de edificación aislada que cuenta con planta baja más 12 alturas. Se estudiará el contenido del proyecto si cumple CTE, control y análisis de cumplimiento de calidad de materiales y de ejecución de unidades constructivas. Además, se hará estudio y seguimiento de plan y estudio en materia de seguridad y salud y, por último, en materia de asunto económico, se analizarán posibles desviaciones de precios entre lo que se tenía programado y lo que finalmente se ha ejecutado en obra., [CA] El projecte es compon de dos volums residencials diferents, un de tipologia lineal en forma de "L" d'alçada variable i l'altre amb tipologia d'edificació aïllada tipus torre. Situat a Benicalap, València. L'objectiu principal consisteix en l'estudi i supervisió de seguiment d'obra de l'edifici de tipologia d'edificació aïllada que compta amb planta baixa més 12 altures. S'estudiarà el contingut del projecte si compleix CTE, control i anàlisi de compliment de qualitat de materials i d'execució d'unitats constructives. A més, es farà estudi i seguiment de pla i estudi en matèria de seguretat i salut i, finalment, en matèria d'assumpte econòmic, s'analitza possibles desviacions de preus entre el que es tenia programat i el que finalment s'ha executat en obra., [EN] The project is made up of two different residential volumes, one of a linear type in the shape of an "L" of variable height and the other with an isolated tower-type building. Located in Benicalap, Valencia. The main objective consists of the study and supervision of the monitoring of the work of the building of the type of isolated building that has a ground floor plus 12 floors. The content of the project will be studied if it complies with CTE, control and analysis of compliance with the quality of materials and execution of construction units. In addition, there will be a study and monitoring of the plan and study on health and safety and, finally, on economic matters, possible price deviations between what was scheduled and what has finally been executed on site will be analyzed.

Este proyecto tiene como objetivo diseñar un aplicativo móvil para el registro y control de datos de pacientes diabéticos, que permita a los pacientes llevar un control ordenado de cada uno de los datos que debe tener en cuenta al momento de tratar su enfermedad, con ello tener un mejor estilo de vida y mejor estado de salud. Al momento del diagnóstico a pacientes con diabetes son muchos los aspectos para tener en cuenta el cuidado de su peso, alimentación, actividad física, niveles de azúcar en la sangre, control en el consumo de medicamentos y todo esto por lo invasiva que puede ser la enfermedad ya que ataca varios órganos del cuerpo como: ojos, piel, riñones, problemas cardiovasculares. Todo ello junto puede ocasionar que las personas se atemoricen y llegue a pensar que esto le impedirá tener un estilo de vida normal. En general, la diabetes es una enfermedad que requiere de bastante atención pero que los cuidados oportunos pueden hacer que la persona tenga una vida saludable y con el control de cada uno de los datos que le permitirá al usuario tener manejo de su enfermedad. Dada esa premisa, se analizan los aspectos técnicos desde la ingeniería de sistemas, que permiten diseñar una aplicación con un alcance determinado para el registro y control de los datos para tener en cuenta por un paciente diabético en el tratamiento de su enfermedad. Para realizar una correcta introducción a los temas de interés del presente proyecto se abordan los conceptos principales con los que se puede comprender de mejor manera el objeto del caso de estudio. De igual manera se definen las soluciones implementadas en la actualidad a nivel global y local en cuanto al uso de la tecnología orientada a la salud. Para cumplir con el objetivo ya trazado se comprende el marco teórico que enmarca el desarrollo del proyecto seguido de la realización de análisis de la enfermedad, levantamiento de requerimientos funcionales y no funcionales, aspectos técnicos que permiten realizar una correcta

The thesis is devoted to the analysis of elliptic PDEs and related problems. It is mainly focused on the study of qualitative and regularity properties of solutions to integro-differential equations. The study of such equations has attracted much attention recently since they arise naturally in different areas when dealing with processes where long range interaction phenomena appear. The canonical example of integro-differential operators is the fractional Laplacian, which is translation, rotation, and scale invariant. The thesis is divided into three parts. Part I concerns the study of uniqueness and regularity properties of solutions to integro-differential linear problems. First, we prove, by following a nonlocal Liouville-type method, the uniqueness of solutions in the one-dimensional case, in the presence of a positive solution or of an odd solution vanishing only at zero. As an application, we deduce the nondegeneracy of layer solutions (bounded and monotone solutions) to semilinear problems of Allen-Cahn type. Next, we establish the first boundary regularity result for the Neumann problem associated to the fractional Laplacian. We prove that weak solutions are Hölder continuous up to the boundary by developing a delicate Moser iteration with logarithmic corrections on the boundary. We also establish a Neumann Liouville-type theorem in a half-space, which is used together with a blow-up argument to show higher regularity of solutions. Part II of the thesis is focused on the study of the saddle-shaped solution to the integro-differential Allen-Cahn equation. These solutions, whose zero level set is the Simons cone, are expected to be the simplest minimizer which is not one-dimensional to the local and nonlocal Allen-Cahn equation in high enough dimensions. It plays, thus, the same role as the Simons cone in the theory of minimal surfaces. First, we study the saddle-shaped solution for the fractional problem by using the extension problem. We establish its uniqu, La tesis está dedicada al análisis de EDPs elípticas y problemas relacionados. Se centra principalmente en el estudio de propiedades cualitativas y de regularidad de soluciones de ecuaciones integro-diferenciales. El estudio de estas ecuaciones ha recibido mucho interés en los últimos tiempos, ya que aparecen de forma natural en diferentes áreas cuando se tratan fenómenos que involucran interacciones de largo alcance. El operador integro-diferencial canónico es el laplaciano fraccionario, que es invariante por traslaciones, rotaciones y cambios de escala. La tesis se divide en tres partes. La primera trata el estudio de propiedades de unicidad y regularidad para soluciones de problemas lineales integro-diferenciales. En primer lugar, probamos, siguiendo un método no local de tipo Liouville, la unicidad de soluciones en el caso unidimensional, en presencia de una solución positiva o de una solución impar que se anula solo en el origen. Como aplicación, deducimos la no degeneración de soluciones 'layer' (soluciones acotadas y monótonas) de problemas semilineales de tipo Allen-Cahn. A continuación, establecemos el primer resultado de regularidad en la frontera para el problema de Neumann asociado al laplaciano fraccionario. Demostramos que las soluciones débiles son Hölder continuas hasta el borde mediante una delicada iteración de Moser con correcciones logarítmicas en la frontera. También establecemos un teorema de tipo Liouville con condiciones de Neumann en un semiespacio, que se usa junto con un argumento de 'blow-up' para demostrar regularidad de orden superior para las soluciones. La parte II de la tesis se centra en el estudio de la solución de tipo silla para la ecuación integro-diferencial de Allen-Cahn. Se espera que estas soluciones, cuyo conjunto de nivel cero es el cono de Simons, sean el minimizante más simple que no unidimensional para la ecuación local y no local de Allen-Cahn en dimensiones suficientemente altas. Juegan, por tanto, el mismo papel que, Postprint (published version)

Final, Resolved

Containment laboratories constitute a fundamental basis for the detection and study of infectious agents and represent an essential tool in the face of emerging and re-emerging diseases that increasingly threaten public health with greater risk. It is necessary to strengthen the management and maintaining these containment laboratories, but under the premise of sustainability in each region or geographic location, and this sustainability must be based not only on the infrastructure level but also on the human potential in its continuous training. Is discussed the importance of containment laboratories as the basis of the epidemiological surveillance system to obtain information for the design of strategies and necessary actions to prevent, mitigate, responding and activating recovery and resilience in the face of any adverse event of a biological nature. of a natural or man-made nature that may affect public health. At the same time, it is intended to raise awareness of the sustainability of the containment system of these laboratories, and thus strengthen their mission and vision, ensuring the well-being of the worker in these areas, the community and the environment, and the guarantee of support at the public health level., Los laboratorios de contención constituyen una base fundamental para la detección y el estudio de agentes infecciosos y representan una herramienta imprescindible ante enfermedades emergentes y reemergentes que cada vez amenazan con mayor riesgo la salud pública. Se hace necesario fortalecer la gestión tanto de obtención como de mantenimiento de estos laboratorios de contención, pero bajo la premisa de sostenibilidad en cada región o localidad geográfica, y esa sostenibilidad debe estar basada no sólo a nivel de infraestructura sino también del potencial humano en su capacitación continua, como un componente fundamental de dichos laboratorios. Se discute la importancia de los laboratorios de contención como base del sistema de vigilancia epidemiológica para obtener información para el diseño de estrategias y actuaciones necesarias con el objetivo de prevenir, mitigar, dar respuesta y accionar la recuperación y resiliencia ante todo evento adverso de naturaleza biológica de índole natural o antrópico que pueda afectar a la salud pública. Paralelamente, se pretende concientizar en la sostenibilidad del sistema de contención de estos laboratorios, y así afianzar su misión y visión, asegurando el bienestar del trabajador de esas áreas, de la comunidad y del ambiente, y la garantía de apoyo a nivel de salud pública.

Despite the recent progresses in the development of inert diets, the rearing of early life stages of aquatic organisms still depends on the use of live feeds. Within live feeds, Artemia sp. and rotifer (Brachionus plicatilis) are widely used in the rearing of marine larvae due to their high availability and acceptance by a large number of species. Nonetheless, both live preys naturally possess low content of long-chain polyunsaturated fatty acids (LC-PUFA) such as 20:5n-3 (EPA), and 22:6n-3 (DHA), which are essential fatty acids (EFA) for proper development of marine fish larvae. In this respect, enrichment of live preys is used to tailor its lipid composition towards the nutritional needs of marine larvae. To improve the design of live prey enrichment protocols, it is advisable to unveil the metabolic fate of fatty acids (FA) during the enrichment process. Therefore, the aim of the present study was to determine the in vivo capability of Artemia sp. metanauplii and rotifers to incorporate and transform unsaturated FA.

Natural transformation is one of the main mechanisms for horizontal gene transfer (HGT) that takes place in bacteria. This allows them to acquire new genetic information, contributing to the spread of antibiotic resistance, metabolic pathways, as well as the emergence of new pathogens. Hence, it is essential to gain basic knowledge of these mechanisms to combat the antibiotic resistance one of the greatest human health challenges. Furthermore, bacteria are constantly subjected to different types of DNA damage, that arise as a consequence of both internal and external factors. Since maintaining the integrity of the genome is essential for cell survival, bacteria cells have developed several mechanisms to prevent, tolerate and repair the damage. LrpC, Hbsu and Rok are Nucleoid Associated Proteins (NAPs) of Bacillus subtilis that bind DNA, facilitating its compaction and structure. Our aim in this work is to see how these proteins are involved in natural transformation and DNA repair mechanisms. What it is shown, is that inactivation of these proteins increases the efficiency of intraspecies chromosomal transformation, and to a lesser extent the efficiency of plasmid transformation. This suggests that these proteins have mainly a structural function. They are naturally associated with DNA, hindering the transformation process. On the other hand, it was found that when B. subtilis cells were exposed to different DNA damage-inducing agents (MMS, 4NQO and MMC), cell survival for Hbsu inactivation mutants (hbsu4755) was decreased compared to the wt. Therefore, it has been shown that Hbsu contributes to the repair or reactivation of the replication fork, that stops in the face of induced damage, favoring cell survival. However, it was also seen that it does not contribute to the repair of fork collapse (damage induced by MMC), despite reactivating the fork when stalled by damage introduced by MMC or 4NQO. Finally, a search for other possible NAPs was carried out, with the a

Los ácidos grasos de cadena muy larga (VLC-FA; >C24), aunque presentes en pequeñas cantidades, juegan un importante papel para el correcto desarrollo y funcionalidad de los tejidos neurales en vertebrados, especialmente durante su desarrollo temprano. Sin embargo, a pesar de su aparente importancia, los estudios sobre estos compuestos en peces son escasos. La biosíntesis de los VLC-FA se lleva a cabo mediante las denominadas proteínas de elongación de los ácidos grasos de cadena muy larga 4 (Elovl4) y, en consecuencia, la dotación y la función de estas enzimas determinan la capacidad endógena que una determinada especie tiene para satisfacer las demandas fisiológicas de VLC-FA, especialmente durante su desarrollo temprano. Además, esta producción endógena de los ácidos grasos poliinsaturados de cadena muy larga (VLC-PUFA) es dependiente de los sustratos. Así, para su biosíntesis se requiere de ácidos grasos más cortos, es decir ácidos grasos poliinsaturados de cadena larga (LC-PUFA; C20-24) que actúen como precursores, los cuales son incorporados principalmente a través de la dieta. Teniendo esto en mente, el presente trabajo de investigación tuvo como objetivos caracterizar los genes elovl4 en dorada (Sparus aurata) y en lenguado senegalés (Solea senegalensis), determinar la función de sus correspondientes proteínas codificadas, así como analizar el patrón de expresión tisular de elovl4. Además, se ha investigado la regulación nutricional de los genes implicados en la biosíntesis de VLC-PUFA (elovl4a, elovl4b) y LC-PUFA (fads2, elovl5) durante las primeras etapas del ciclo de vida de ambas especies (larvas y poslarvas), mediante el uso de dietas adaptadas a cada etapa del desarrollo. Los resultados confirmaron que ambas especies de peces poseen dos genes elovl4 distintos, denominados elovl4a y elovl4b según su homología con sus ortólogos de pez cebra. Asimismo, los ensayos funcionales de sus correspondientes proteínas, llevados a cabo en levaduras, indicaron que ta

Marine invertebrates in general and polychaetes in particular, are attracting a great deal of attention as promising candidates for their use as alternative ingredients for aquaculture. Polychaetes are good sources of long-chain (C20-24) polyunsaturated fatty acids (LC-PUFA), especially the so-called ¿omega-3¿ (¿3 or n-3) eicosapentaenoic acid (EPA, 20:5n-3) and, to a lesser extent, docosahexaenoic acid (DHA, 22:6n-3). Their nutritional value, along with their detritivorous feeding habits enabling their culture on sidestreams from agri-food industries, has prompted interest to explore circular economy strategies for production of polychaete meals as alternative ingredients to fishmeal for aquafeed formulation [1]. Fatty acid (FA) composition of animals is accounted for by diet and endogenous production (biosynthesis). Interestingly, LC-PUFA biosynthesis can be modulated by diet (nutritional regulation) and environmental factors such as temperature [2]. This offers a great opportunity to establish culture protocols that enhance ¿3 LC-PUFA biosynthesis and therefore result in production of highly nutritious polychaete biomasses. The present study aimed to assess the combined effects of diets varying in LC-PUFA composition and temperature on the FA profiles of the nereid polychaete Hediste diversicolor. No temperature-driven segregation patterns could be identified in the FA profiles of H. diversicolor, which is in agreement with former reports [3]. The present work thus confirms that diet is the major factor influencing lipid composition in this species as reported by [4]. The segregation of the FA patterns of the control (FF) group was associated to LA and DHA, major constituents of fish aquafeeds [1,4]. In fact, the lack of a clear effect of si

[Introduction]: The fast and remarkable growth of global aquaculture in the recent years has created new economic and ecological challenges. With regard to fish farming, such challenges have been mostly linked to guarantee the supply of raw materials used for feed formulation in order to reduce the current usage of finite resources such as fishmeal and fish oil. Gammarids, particularly their biomasses, have prompted interest as alternative sources for feed formulation due to their nutritional profile. Recent studies have reported the ability of gammarids to grow on a wide range of sidestreams while accumulating relatively high levels of long-chain (C20-24) polyunsaturated fatty acids (LC-PUFA), physiologically essential compounds for normal growth and development of vertebrates. Diet and temperature have been suggested to modulate the abundance of LC-PUFA in aquatic invertebrates. Here, we aimed to elucidate the effects of three diets (the seaweed Fucus sp., carrot leaves, coconut flesh) and four different temperatures (5, 10, 15, and 20°C) on LC-PUFA profiles of Gammarus locusta, a marine gammarid with capacity for trophic upgrading when grown in low-LC-PUFA diets. [Results]: FA analysis of diets showed that coconut is rich in saturated fatty acids (SFA) in comparison to Fucus sp. and carrot leaves. Regarding LC-PUFA, Fucus sp. showed moderate levels of arachidonic acid (ARA, 11.96%) and eicosapentaenoic acid (EPA, 4.81%), and lower levels of docosahexaenoic acid (DHA). Both coconut and carrot leaves diets lack LC-PUFA. FA analysis of G. locusta showed that temperature did not significantly influenced the composition of gammarids irrespectively of the diet. However, the G. locusta FA profiles varied with diets. Statistical analysis revealed that diet is the leading factor accounting for the G. locusta FA profiles (p < 0.05). Interestingly, gammarids fed on Fucus sp. showed the highest content of total lipids among all dietary treatments, and a fairly similar FA pro

Seasonal changes in condition index and the biochemical components (proteins, lipids and glycogen) of the gonad/digestive gland, foot, labial palp, mantle, gills and adductor muscles of Donax trunculus Linnaeus, 1758 from the Gulf of Tunis were monitored seasonally, from November 2006 to October 2007, in relation to environmental conditions and reproductive events. The condition index increased during late gametogenesis and the ripe stage, coinciding with enrichment of the water by phytoplankton, and decreased during late summer and autumn (i.e. the spawning and rest periods). Glycogen increased during early gametogenesis and peaked during winter, pointing to its mobilisation in the formation of active ripe gametes. The foot, gonad/digestive gland, and adductor muscle were the three major glycogen-reserve tissues. Protein content was high during the end of summer in the whole individual and during autumn in the gonad/digestive gland. Lipid content started to increase as gametogenesis began, reached its peak at gonad ripeness and during the early spawning stage (summer) and sharply declined due to the shedding of gametes (autumn). A transformation of glycogen for de novo synthesis of lipids, in the gonad/ digestive gland, was suggested during the later stages of the gonadic cycle, in support of gametogenesis. Temporal fluctuations in environmental factors, particularly temperature and food supply, drive the cycle of storage and utilisation of metabolic energy reserves which in turn govern gametogenesis in Donax trunculus.

[EN]: Very long-chain (˃ C24) fatty acids (VLC-FA) play critical roles during early development of vertebrates, since these compounds are accumulated in the rapidly forming neural tissues, ensuring their normal function. The functionality of VLC-FA has aroused scientific interest, focusing on the study of elongases protein 4 of very long chain fatty acid (Elovl4), which are responsible for their biosynthesis from shorter fatty acids (precursors). For a better understanding of the metabolism and the potential tissue-specific requirements of VLC-FA in marine teleosts, the present study aimed to determine the tissue-expression pattern of the genes that encode for Elovl4 isoforms, i.e. elovl4aand elovl4b, in different windows of development (larval and adult stages) of Gilthead seabream Sparus aurataand Senegalese sole Solea senegalensis.The results indicated that in S. auratalarvae, elovl4a is widely expressed in the head, while elovl4bis strongly focused in the eyes. Interestingly, in S. senegalensislarvae an opposite tissue-expression pattern was observed for both elovl4isoforms. In adults of both fish, although elovl4transcripts were detected in most tissues analyzed, elovl4aand elovl4bgenes were strongly expressed in brain and eyes, respectively. Importantly, the differential tissue-expression pattern of both elovl4isoforms associated to the pre-and post-metamorphic stage of S. senegalensis could be indicative of the VLC-FA particular needs linked to neural tissues functionality in each development stage. These findings can contribute to a better understanding of the species-specific VLC-FA metabolism in marine teleosts., [ES]: Los ácidos grasos de cadena muy larga (¿ C24) (VLC-FA) juegan un papel crítico durante el desarrollo temprano de los vertebrados, ya que estos compuestos se acumulan en los tejidos neurales que se forman rápidamente, asegurando su función normal. La funcionalidad de los VLC-FA ha despertado el interés científico, centrándose en el estudio de las proteínas elongasas 4 de ácidos grasos de cadena muy larga (Elovl4), que son responsables de su biosíntesis a partir de ácidos grasos más cortos (precursores). Para comprender mejor el metabolismo y los potenciales requisitos a nivel tisular de los VLC-FA en teleósteos marinos, el presente estudio tuvo como objetivo determinar el patrón de expresión tisular de los genes que codifican las isoformas de Elovl4, es decir, elovl4a y elovl4b, en diferentes ventanas del desarrollo (larvas y adultos) de dorada (Sparus aurata) y lenguado senegalés (Solea senegalensis). Los resultados indicaron que en las larvas de S. aurata, elovl4a se expresa ampliamente en la región cerebral, mientras que elovl4b se expresa intensamente en los ojos. Curiosamente, en las larvas de S. senegalensis se observó un patrón de expresión tisular opuesto, siendo elovl4a y elovl4b fuertemente expresado en ojos y región cerebral, respectivamente. En adultos de ambas especies, aunque se detectaron transcritos de elovl4 en la mayoría de los tejidos analizados, los mayores valores de expresión de elovl4a y elovl4b se observaron en el cerebro y en los ojos, respectivamente. Es importante destacar que el diferente patrón de expresión tisular observado para ambos genes elovl4 asociados a la etapa pre y posmetamórfica de S. senegalensis podría ser indicativo de las necesidades particulares de VLC-FA vinculadas a la funcionalidad de los tejidos neurales en cada etapa de desarrollo. Estos hallazgos pueden contribuir a una mejor comprensión del metabolismo de VLC-FA específico en función de la especie de teleósteo marino.

[Introduction]: Aquaculture of carnivorous species is greatly dependent on the supply of marine ingredients, which provide adequate levels of essential nutrients including long-chain (C20¿24) polyunsaturated fatty acids (LC-PUFAs), particularly the ¿omega-3¿ (¿3) including eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). Primary production of these compounds was thought to take place exclusively by the action of photosynthetic microalgae, heterotrophic protists and bacteria. However, a study has revealed that multiple aquatic invertebrates including polychaetes possess enzymes that enable them to produce ¿3 LC-PUFAs de novo and, consequently, their culture with an adequate supply of biosynthetic fatty acid (FA) precursors and enhancing such pathways emerges as a highly innovative strategy to produce nutritious and sustainably sourced ingredients for aquaculture. The capacity by which an animal species can biosynthesise LC-PUFAs depends upon the complement and function of two types of enzymes, namely fatty acyl elongases and desaturases. The aim of the present study was to characterise molecularly and functionally two elongases (Elo) and one front-end desaturase (Fed) involved in the LC-PUFA biosynthesis of the common ragworm Hediste diversicolor. Our results show that H. diversicolor has at least two Elo and one Fed with putative roles in the LC-PUFA biosynthetic pathways. We termed them as Elovl2/5 and Elovl4 based on their phylogenetic relationship with well characterised elongases from other animals. Functional characterisation results showed that the H. diversicolor Elovl2/5 is indeed a PUFA elongase since elongated PUFA substrates with C18 and C20. Similarly, the H. diversicolor Elovl4 showed elongation capacity towards C18 and C20 PUFA substrates but, additionally, C22 PUFA substrates. Functional characterisation of the H. diversicolor Fed1 confirmed its role in the LC¿PUFA biosynthesis as it showed this enzyme has ¿5 activity conv

The aim of this study was to determine the nutritional value of three populations of Artemia, one from the Bethioua Sebkha (Oran) and two new biotopes at El Melah (Bechar) and Timimoune (Adrar), by evaluating the cyst and nauplius biometry, hatching parameters and fatty acid profiles. This information is of relevance to aquaculture initiatives, and fills in knowledge gaps from previous research at Algerian sites. The size of nauplii varied from 453.26 ± 0.3 µm and 478.73 ± 0.2 µm. The chorion thickness was between 13.28 µm and 10.50 µm. The highest hatching percentage and hatching efficiency were obtained after decapsulation of Bethioua cysts. The shortest hatching synchrony time was also found for the Bethioua cysts. All cyst samples from the the Bethioua population analysed in this study showed a freshwater-type fatty acid profile, rich in linolenic acid (LNA, 18:3n.3), opposed to a marine-type fatty acid profile rich in presence of eicosapentaenoic acid (EPA, 20:5n-3). The Bethioua population exhibited the best hatching performance and are ideally suited for use in aquaculture.