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[spa] El objetivo general de esta tesis ha sido evaluar los efectos de determinados contaminantes sobre la reproducción, el estrés fisiológico y el comportamiento dos especies de ciprínidos autóctonas del NE de Cataluña y el SE de Francia. Esta es una tesis que ha buscado analizar, desde un punto de vista multidisciplinar, y combinando trabajos de campo con experimentos de laboratorio, los efectos de la contaminación sobre las poblaciones de peces. Con este propósito general se establecieron los siguientes objetivos específicos: • Evaluar, en un ambiente natural, los posibles efectos de la contaminación de origen industrial, frecuente en los ríos mediterráneos, sobre la biología reproductiva del bagre (Squalius laietanus). A tal efecto se planteó describir el ciclo gonadal, calcular la fecundidad y analizar la posible presencia de histopatologías en ovarios y testículos para determinar cómo la presencia de contaminantes considerados disruptores endocrinos podía alterar la biología reproductiva de este ciprínido autóctono. El estudio fue complementado mediante un análisis por biomarcadores. • Analizar el efecto de la contaminación urbana sobre el estrés fisiológico de S. laietanus mediante el análisis de cortisol en moco epidérmico. El objetivo fue validar una técnica de análisis del cortisol por métodos no invasivos (moco epidérmico) y utilizarla como método para determinar el grado de bienestar de esta especie bajo los efectos de la mencionada contaminación. • Evaluar el efecto de la contaminación por amonio sobre el comportamiento en el barbo de montaña (Barbus meridionalis) en condiciones experimentales de laboratorio. En particular, se analizaría también si la exposición previa de los peces a este contaminante en un ambiente natural podría predisponerlos a una mejor tolerancia después de haber sido detoxificados en el laboratorio. Los peces serían sometidos a diferentes concentraciones subletales de amonio y se analizaría tanto su comportamiento alimentario (voracidad y saciedad) como su actividad de natación. • Determinar el efecto de la contaminación por amonio sobre la personalidad de B. meridionalis en condiciones experimentales de laboratorio. En particular, se investigó sobre su capacidad de retención de memoria tras haber pasado por una experiencia de aprendizaje apetitivo basada en un test de osadía (en ausencia de amonio) y tras haber sido expuesto a diferentes concentraciones subletales de este contaminante en posteriores test., [eng] Mediterranean rivers are subject to intense pollution of anthropic origin. Among the most frequent pollutants are ammonia and emerging compounds such as endocrine system disruptors (EDCs). This thesis has analyzed the effects of some of these pollutants on the reproduction and physiological stress of the Catalan chub (Squalius laietanus) and on the behavior of the Mediterranean barbel (Barbus meridionalis), two cyprinids native to the Iberian Peninsula. In field studies carried out in S. laietanus (Besòs river basin), EDCs such as benzotriazole and benzothiazole (coming from a textile industry) could be responsible for both a decrease in the gonadosomatic index (in both sexes) and a lower fecundity and spawn desynchronization (in females), as well as a smaller diameter in the seminiferous tubules of males. Higher levels of stress (cortisol) found in both blood and epidermal mucus, as well as the abnormalities detected in red and white blood cells of S. laietanus, were attributable to urban pollution from sewage treatment plants. In B. meridionalis, through experimental laboratory studies, it was shown that ammonia (at sublethal concentrations) altered feeding behavior (voracity and satiety), but not swimming activity. However, in fish that had been pre-exposed to ammonia (in the natural environment), these alterations occurred in absence of this compound. In another experiment, also carried out in B. meridionalis and aimed at investigating the effect of ammonia on the cognition, exposed fish were found to have poorer memory retention than non exposed ones. After a learning experience, individuals of this species were able to retain memory for at least 16 days, which is considered long-term memory.

International audience; Rivers suffer from more severe decreases in species diversity compared to other aquatic and terrestrial ecosys- tems due to a variety of pressures related to human activities. Species provide different roles in the functioning of the ecosystem, and their loss may reduce the capacity of the ecosystems to respond to multiple stressors. The effects on diversity will differ based on the type, combination and severity of stressors, as well as on the char- acteristics of the community composition and tolerance. Multiple trait-based approaches (MTBAs) can help to unravel the effects of multiple stressors on communities, providing a mechanistic interpretation, and, thus, complementing traditional biodiversity assessments using community structure. We studied the relationships between diversity indexes and trait composition of macroinvertebrate and diatom communities, as well as envi- ronmental variables that described the hydrological and geomorphological alterations and toxic pollution (pes- ticides and pharmaceuticals) of three different European river basins: the Adige, the Sava, and the Evrotas. These river basins can be considered representative cases of different situations in European freshwater systems. Hy- drological variables were the main drivers determining the community structure and function in the rivers, for both diatoms and macroinvertebrates. For diatom communities, pharmaceutical active compound (PhAC) toxic units were also identified as a very important driver of diversity changes, explaining up to 57% of the variance in taxonomic richness. For macroinvertebrates, river geomorphology was an important driver of structural changes, particularly affecting Plecoptera richness. In addition, PhAC and pesticide toxic units were also identified as stressors for macroinvertebrate communities. MTBA provided a detailed picture of the effects of the stressors on the communities and confirmed the importance of hydrological variables in shaping the functional attributes of the communities.

Organisms can develop different kinds of asymmetry when deviations from expected perfect symmetry occur. Among others are fluctuating asymmetry (FA) and directional asymmetry (DA). FA represents small random differences between corresponding parts on the left and right sides of an individual in bilaterally paired structures. It is thought that FA reflects an organism's ability to cope with genetic and environmental stress during growth. DA occurs whenever one side on the plane of symmetry develops more than the other side, and has a genetic component. In this research, we examined the expression of morphological symmetry in 38 skulls of different age groups of wild boar (Sus scrofa), on their ventral aspect, using two-dimensional coordinates of 27 landmarks. Analyses showed the presence of significant FA and DA in the entire sample, detecting also distinctive differences between age groups. The obtained results show that the shape differences in different age groups could reasonably be a consequence of a response to environmental factors for FA and a masticatory lateralization for DA. Os organismos podem desenvolver diferentes tipos de assimetria quando ocorrem desvios da pefeita simetria esperada. Entre os diversos tipos de assimetria existentes duas merecem especial destaque: a flutuante (AF) e a directional (AD). A AF é representada por pequenas diferenças casuais entre as partes correspondents das laterais direita e esquerda de um indivíduo em estruturas pareadas bilateralmente; acredita-se que elas reflitam a habilidade de um organismo adaptar-se a fatores estressantes genéticos e ambientais observados durante o seu crescimentos. A AD ocorre quando um lado da assimetria plana desenvolve-se mais do que o outro e há um componente genético. No presente trabalho foi analisada a expresssão da simetria morfológica de 38 crânios de diferentes grupos etários de javalis (Sus scrofa), nos seus aspectos ventrais, com o emprego de duas coordenadas dimensionais de 27 pontos anatômicos homólogos. As análises efetuadas revelaram a existência de valores significantes de AF e AD em toda a amostra trabalhada, detectando inclusive diferenças entre os grupos etários. Os resultados obtidos demonstraram que as diferentes formas observadas nos diferentes grupos etários podem ser consequência de uma resposta a fatores ambientais para a AF e a lateralização da mastigação para a AD.

Intensive exercise can lead to oxidative stress, which can be particularly deleterious for lymphoid tissues. Hesperidin has demonstrated its antioxidant activity, but few studies focus on its influence on intensive training. The aim of this study was to assess the impact of hesperidin on the oxidant/antioxidant status of lymphoid tissues after an intensive training program. Wistar rats were trained for five weeks (five days per week), including two exhaustion tests plus three trainings per week. During this period, animals were orally administrated with 200 mg/kg of hesperidin or vehicle (three days per week). The oxidative status was determined before, immediately after and 24 h after an additional exhaustion test. The production of reactive oxygen species (ROS) by peritoneal macrophages, superoxide dismutase (SOD) and catalase activities in spleen, thymus and liver, and hepatic glutathione peroxidase activity (GPx) were assessed. Hesperidin prevented an increase in ROS production induced by the additional exhaustion test. Likewise, hesperidin avoided a decrease in SOD and catalase activities in the thymus and spleen that was found after the additional exhaustion test. The antioxidant effects of hesperidin were associated with a higher performance in the assessed training model. These results suggest that hesperidin, acting as an antioxidant, can prevent oxidative stress induced by exercise and improve exercise performance.

Organisms can develop different kinds of asymmetry when deviations from expected perfect symmetry occur. Among others are fluctuating asymmetry (FA) and directional asymmetry (DA). FA represents small random differences between corresponding parts on the left and right sides of an individual in bilaterally paired structures. It is thought that FA reflects an organism's ability to cope with genetic and environmental stress during growth. DA occurs whenever one side on the plane of symmetry develops more than the other side, and has a genetic component. In this research, we examined the expression of morphological symmetry in 38 skulls of different age groups of wild boar (Sus scrofa), on their ventral aspect, using two-dimensional coordinates of 27 landmarks. Analyses showed the presence of significant FA and DA in the entire sample, detecting also distinctive differences between age groups. The obtained results show that the shape differences in different age groups could reasonably be a consequence of a response to environmental factors for FA and a masticatory lateralization for DA. Os organismos podem desenvolver diferentes tipos de assimetria quando ocorrem desvios da pefeita simetria esperada. Entre os diversos tipos de assimetria existentes duas merecem especial destaque: a flutuante (AF) e a directional (AD). A AF é representada por pequenas diferenças casuais entre as partes correspondents das laterais direita e esquerda de um indivíduo em estruturas pareadas bilateralmente; acredita-se que elas reflitam a habilidade de um organismo adaptar-se a fatores estressantes genéticos e ambientais observados durante o seu crescimentos. A AD ocorre quando um lado da assimetria plana desenvolve-se mais do que o outro e há um componente genético. No presente trabalho foi analisada a expresssão da simetria morfológica de 38 crânios de diferentes grupos etários de javalis (Sus scrofa), nos seus aspectos ventrais, com o emprego de duas coordenadas dimensionais de 27 pontos anatômicos homólogos. As análises efetuadas revelaram a existência de valores significantes de AF e AD em toda a amostra trabalhada, detectando inclusive diferenças entre os grupos etários. Os resultados obtidos demonstraram que as diferentes formas observadas nos diferentes grupos etários podem ser consequência de uma resposta a fatores ambientais para a AF e a lateralização da mastigação para a AD.

[spa] Esta tesis parte del estudio de un grupo de especies de escarabajos acuáticos (Agabus brunneus complex) que poseen diferencias importantes en el tamaño de sus rangos geográficos, contando con una especie insular (A. rufulus), una continental de rango restringido (A. ramblae) y una continental de rango amplio (A. brunneus) para estudiar los factores implicados en esas diferencias. Este complejo de especies diversificó a finales del Pleistoceno en la península ibérica posiblemente tras la colonización de A. ramblae desde Marruecos. Una de las especies resultantes A. brunneus en algún momento de la diversificación desarrolló la capacidad de resistencia a bajas temperaturas lo que le facilitó el poder extender su rango hacia climas más fríos. Se empleó la proteómica de poblaciones para analizar la respuesta de varias poblaciones de A. brunneus y A. ramblae frente a temperaturas que pueden experimentar en la naturaleza. Al estudiar la variabilidad a distintos niveles entre dos poblaciones naturales de A. ramblae obtuvimos una buena reproducibilidad de nuestros experimentos. Al analizar de forma global dos poblaciones para cada especie (Marruecos y península ibérica para ambas) descubrimos que la diversificación de la filogenia ha ido acompañada de cambios en la respuesta a nivel de expresión proteínica. La mayoría de las proteínas identificadas están relacionadas con el metabolismo energético y con proteínas del estrés, estas últimas se expresan diferencialmente entre las dos especies analizadas, indicando una diferente respuesta al estrés térmico. El presente trabajo abre la posibilidad de realizar este tipo de experimentos empleando poblaciones naturales de especies no modelo y demuestra que la respuesta frente al estrés de un factor ambiental, en este caso la temperatura, puede recuperarse empleando para ello la proteómica. Así mismo las diferencias en el tamaño del rango pueden ir acompañadas de la adquisición de distinta capacidad de respuesta frente al estrés térmico, [eng] This thesis studies a group of aquatic beetles (Agabus brunneus complex) that present important differences in the size of their geographic ranges. This complex is composed by an insular species (A. rufulus), a continental species with restricted range (A. ramblae) and another continental species (A. brunneus) that posses a wide range of distribution (A. brunneus) with the aim of study the factors implied in those differences. For this purpose we integrated the phylogeny/ phylogeography of the group and the evolution of the ecological niche together with morphological study and thermal tolerance of species. This complex of species diversified at the end of Pleistocene in Iberian Peninsula probably after the colonization of A. ramblae from Morocco. One of the resultant species (A. brunneus) at some point of the diversification acquired the ability to resist colder temperatures and was able to disperse to colder climates. To understand range variability from another perspective we used population proteomics to analyse the response of several populations for A. ramblae and A. bruneus facing temperatures that they might experience on field. We decided to analyse the variability at several levels in two populations of (A. ramblae) when working with natural populations obtaining satisfactory results for the reproducibility of our experimental methodology. When we analysed globally two populations for each species (one from Morocco and one from Iberian peninsula for each) we saw that the diversification observed in the phylogeny was encompassed with changes at the proteomic response. The more common proteins identified belong to energetic metabolism and stress proteins. The latter were detected to express differentially between the two species studied, showing a different response to thermal stress. This work address the possibility of employing population proteomics in natural populations of non-model species and being able of recovering the stress response facing an environmental factor like temperature. We show as well that differences in range size can be encompassing with the acquisition of capacity to face thermal stress.

El interés en identificar los factores ecológicos que afectan a la abundancia y bienestar de los animales ha tomado una creciente importancia debido a la necesidad de desarrollar planes de conservación efectivos para las especies amenazadas. Con respecto a los primates de bosques tropicales, estos temas son particularmente críticos debido a la rápida transformación antropogénica de su hábitat. El objetivo general de este trabajo fue evaluar si las poblaciones de mono aullador de manto (Alouatta palliata mexicana) en la zona de Los Tuxtlas (México) se ven negativamente afectadas por los efectos de la fragmentación de su hábitat, en particular por aquellos relacionados con el estrés, así como la posible influencia de tales efectos sobre la competencia intragrupo por el alimento y distintos aspectos de su reproducción. Con este propósito, desde febrero de 2004 a enero de 2005, medimos distintos parámetros fisiológicos (glucocorticoides fecales) y conductuales (dimensión fractal del comportamiento) de 3 grupos de aulladores, cada uno en un fragmento de selva con características socio-ecológicas distintas reflejo de un gradiente en la calidad de hábitat entre tales fragmentos. Los mayores niveles de glucocorticoides -tanto en machos como en hembras- encontrados en el grupo habitante del fragmento de peor calidad sugieren que una excesiva fragmentación del hábitat puede conducir a una elevación crónica en los niveles de estrés y desembocar en efectos a largo plazo sobre la viabilidad de los grupos de aulladores recluidos en fragmentos de selva. Además se registró un gradiente ascendente en los niveles de agonismo en contexto de alimentación conforme disminuyó la extensión y la calidad del fragmento de selva ocupado. El efecto combinado de una menor disponibilidad de alimento y un mayor grado de competencia por el mismo podría ser la causa del patrón de estrés descrito a partir de los parámetros hormonales y conductuales. Por otro lado, la fragmentación del hábitat parece estar afectando al éxito reproductivo del mono aullador de manto en la zona de estudio, no así sobre su capacidad reproductiva. Con todo, los resultados obtenidos en esta tesis sugieren que, superado un umbral de perturbación y fragmentación del hábitat, se puede alcanzar una situación crónica estresante y, por tanto, comprometer de forma efectiva la salud y las probabilidades de supervivencia a largo plazo de las poblaciones de mono aullador en libertad. Por ello, las estrategias de conservación de la subespecie estudiada de mono aullador de manto (Alouatta palliata mexicana) deberían enfocarse al mantenimiento de grandes parches de selva no alterada más que a la preservación de núcleos marginales de población. Además, estas medidas deberían aplicarse de modo inmediato dada la especial propensión de las poblaciones de esta subespecie a la alteración antropogénica de su hábitat., The interest in identifying the ecological factors that influence animal abundance has taken on a new importance with the need to develop informed conservation plans for endangered and threatened species. With respect to forest-dwelling primates, these issues are critical because tropical forests are undergoing rapid anthropogenic transformation. The objective of this thesis was to evaluate whether the Mexican howler monkeys population at Los Tuxtlas (Mexico) are negatively influenced by habitat fragmentation effects, particularly by those associated with stress and their possible influence on feeding intra-group competition and reproduction. To this end, over the course of a year, we studied several physiological (glucocorticoid levels) and behavioural parameters (fractal dimension of behaviour) of three groups of howler monkeys inhabiting three forest fragments characterised by decreasing habitat quality. The major levels of glucocorticoids found in the group inhabiting the poor quality fragment, suggest that an extensive habitat fragmentation could led to chronic elevation of stress levels and, with that, affect the viability of howler monkeys groups confine into forest fragments. Moreover, we registered an ascendant gradient in agonism levels in feeding context as decreasing the area and quality of the occupied fragment. Therefore, the pattern in stress level registered could be due to a low food availability and high intra-group competition for these resources. On the other hand, habitat fragmentation seems to affect the reproductive successes of howler monkeys at study area, but not yet their reproductive capacity. In conclusion, results suggest that exceeded a threshold of habitat disturbance and fragmentation, it is possible to reach a chronic stress situation, and therefore, to jeopardize the health and the long-term survival probabilities of free howler monkeys. We suggest that conservation strategies of this subspecies must be managed to the maintenance of great and not disturbing forests fragment more than the preservation of marginal population groups, and it should be immediately applied since the special tendency to the habitat disturbance of this subspecies.

We studied the variations caused by stress in lipoprotein lipase (LPL) activity, LPL-mRNA, and local blood flow in LPL-rich tissues in the rat. Stress was produced by body immobilization (Immo): the rat's limbs were taped to metal mounts, and its head was placed in a plastic tube. Chronic stress (2 h daily of Immo) decreased total LPL activity in mesenteric and epididymal white adipose tissue (WAT) and was accompanied by a weight reduction of these tissues. In limb muscle, heart, and adrenals, total LPL activity and mRNA levels increased, and, in plasma, LPL activity and mass also increased. Acute stress (30-min Immo) caused a decrease in total LPL activity only in retroperitoneal WAT and an increase in preheparin plasma active LPL, but the overall weight of this tissue did not vary significantly. We propose an early release of the enzyme from this tissue into the bloodstream by some unknown extracellular pathways or other local mechanisms. These changes in this key energy-regulating enzyme are probably induced by catecholamines. They modify the flow of energy substrates between tissues, switching the WAT from importer to exporter of free fatty acids and favoring the uptake by muscle of circulating triacylglycerides for energy supply. Moreover, we found that acute stress almost doubled blood flow in all WAT studied, favoring the export of free fatty acids.

7 páginas, 4 figuras., Sporadic mass mortality events of Mediterranean sponges following periods of anomalously high temperatures or longer than usual stratification of the seawater column (i.e. low food availability) suggest that these animals are sensitive to environmental stresses. The Mediterranean sponges Ircinia fasciculata and I. oros harbor distinct, species-specific bacterial communities that are highly stable over time and space but little is known about how anomalous environmental conditions affect the structure of the resident bacterial communities. Here, we monitored the bacterial communities in I. fasciculata (largely affected by mass mortalities) and I. oros (overall unaffected) maintained in aquaria during 3 weeks under 4 treatments that mimicked realistic stress pressures: control conditions (13uC, unfiltered seawater), low food availability (13uC, 0.1 mm-filtered seawater), elevated temperatures (25uC, unfiltered seawater), and a combination of the 2 stressors (25uC, 0.1 mm-filtered seawater). Bacterial community structure was assessed using terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA gene sequences and transmission electron microscopy (TEM). As I. fasciculata harbors cyanobacteria, we also measured chlorophyll a (chl a) levels in this species. Multivariate analysis revealed no significant differences in bacterial T-RFLP profiles among treatments for either host sponge species, indicating no effect of high temperatures and food shortage on symbiont community structure. In I. fasciculata, chl a content did not significantly differ among treatments although TEM micrographs revealed some cyanobacteria cells undergoing degradation when exposed to both elevated temperature and food shortage conditions. Arguably, longer-term treatments (months) could have eventually affected bacterial community structure. However, we evidenced no appreciable decay of the symbiotic community in response to medium-term (3 weeks) environmental anomalies purported to cause the recurrent sponge mortality episodes. Thus, changes in symbiont structure are not likely the proximate cause for these reported mortality events.