First feeding behavior: A potential tool to select robust trout for organic aquaculture

In wild salmonid fish, individual behavioural traits have been suggested to be coupled with the timing of fry emergence form gravel spawning nests, in such a way that early emerging fish have shown to be more aggressive and to have a higher probability to become socially dominant than those fish emerging at a later stage. Besides aggression and dominance, other behavioural and metabolic traits such as boldness, metabolic rate or growth had also been coupled to emergence time. Altogether, early- and late-emerging fish have traits resembling those of proactive and reactive stress coping styles, respectively. Proactive fish are considered to be more resilient to stress. However, it is currently unclear if that coupling is maintained in farmed fish populations, which showed no consistent evidence of a clear relation between emergence time and stress coping style. In this study, fish were hatched and larvae were fractionated according their emergence time (Early fraction: first 20 % of fish to emerge; Intermediate fraction: mid 20 %; Late fraction: last 20 %). Several months later, the resilience against a mild stressor (30 min of high stocking density), along with the stress habituation ability was investigated in 5 g fish from the different fractions. Results showed that fish from different fractions played a similar neuroendocrine response to a novel stressor. Interestingly, the capacity of habituation to stress was however better in the fish from the early emergence fraction, which showed no cortisol response to the stressor after being exposed daily for 15 days to another mild acute stressor (1.5 min of air exposure). These results demonstrate that at least some behavioural differences related to emergence time exist in a domesticated trout population. The aquaculture related implications of these stress resilience differences are currently under study

Estimación de los puntos de Fekete en la esfera unidad

Esta tesina se centra en el problema matemático de conseguir distribuir bien una cantidad cualquiera de puntos sobre la superficie de una esfera. Este problema admite multitud de variantes; nosotros estudiaremos tres de ellas: disponer n cargas eléctricas puntuales iguales y del mismo signo sobre la superficie de la esfera de manera que estén en equilibrio electrostático; disponer n partículas puntuales sobre la superficie de la esfera de manera que sea máximo el producto de todas sus distancias euclídeas dos a dos y disponer n partículas puntuales sobre la superficie de la esfera de manera que sea máxima la suma de todas sus distancias euclídeas dos a dos. El primero de estos problemas suele aparecer en la literatura como problema de J.J. Thomson y el segundo como problema de Fekete, y a las distribuciones de puntos que resuelven este último se les da el nombre de puntos de Fekete de orden n en la esfera. También es habitual encontrar que esos tres problemas y otros similares se engloben bajo el nombre común de problema de los puntos de Fekete. Haciendo uso de los principios de la Teoría del Potencial es posible plantear los tres problemas anteriores en términos de la minimización de un cierto funcional de energía potencial cuya expresión varía según el caso. Nosotros proponemos un nuevo algoritmo numérico de localización de mínimos de esos funcionales de energía restringidos a la esfera unidad S2

Fiskevelfærd i økologisk ørred opdræt Er der forskel på EU-regelsættet og RSPCA standarden?

Opdræt af regnbueørred, især økologisk ørred, er kritisk udfordret på grund af relativt mange hud/gælle infektioner forårsaget af forskellige patogener, især parasitten Costia (Ichthyobodo necator), som ultimativt er dødelig for yngel/mindre fisk. Dette kan være en trussel mod tilstrækkelig udbud af økologisk yngel til videre produktion, da regelsættet for økologisk akvakultur kræver 100% økologisk yngel. Endvidere forårsager en såkaldt ny ”Rickettsia-lignende" bakterie “rødpletsyge” (RMS), dvs. røde pletter i huden, som medfører ned-klassificering/kassation af op til 30% af fiskene ved slagtning. Behandling ved brug af antibiotika/hjælpestoffer er kun muligt i begrænset omfang i økologisk ørred produktion. Løsninger til forebyggelse og/eller behandling af Costia og RMS er derfor strengt påkrævet – ikke kun for blot at sikre produktion af økologisk ørred i Danmark, men også for at styrke grundlaget for en større produktion af robuste økologiske fisk. ShelterFish vil fokusere på løsninger i krydsfeltet: Fisk - Patogener – Opdrætssystem/miljø og vandkvalitet; omfattende 1) Test af skjul/skygge med henblik på at skabe bedre og robust opdrætsmiljø; 2) Test af urte ekstrakter og et nyt bakterielt overfladeaktivt stof til behandling af gæller/hud parasit infektioner; 3) Test af induceret immunitet mod ”rødpletsyge” og 4) Test af metoder til reduktion af belastning med organisk stof i økologiske dambrug og herved forbedre vandkvalitet/miljø, fiske sundhed og velfærd. Fiskevelfærd har høj fokus i såvel det fælles EU regelsæt for økologisk akvakultur som i den engelske dyreværnsorganisations RSPCA standard. Økologisk ørred opdræt sker i dag efter fælles EU-regler. Fiskevelfærd er væsentlig for enhver akvakultur produktion og er særligt fremtrædende i det økologiske EU-regelsæt. Men der findes også andre regelsæt, der har primær fokus på fiskevelfærd som f. eks. den engelske RSPCA standard. RSPCA er forkortelsen for: Royal Society for the Prevention of Cruelty to Animals, der er en non-profit engelsk dyreværnsorganisation med sit eget “RSPCA Assured” mærke. Men tager det ene regelsæt mere hensyn til fiskevelfærd end det andet? Dette søges belyst i denne artikel i forhold til EU-regelsættet og RSPCA standarden

Reproductive succed of an alien invasive plant in the Ártabro Gulf

[Resumo] En este trabajo se evalúa el éxito reproductivo y el potencial invasor de diferentes muestras de la especie Helychrisum petiolare Hilliard & Burtt, pertenecientes a diferentes poblaciones, situadas todas ellas dentro del Golfo Ártabro. Se analizan 2 poblaciones con numerosos individuos que juegan el papel de poblaciones madre, y 4 poblaciones aisladas, con el objetivo de determinar si esta especie presenta una reproducción sexual efectiva, además de resolver si en las poblaciones aisladas ocurre depresión por aislamiento respecto a las poblaciones madre, o por el contrario, su éxito reproductivo y potencial invasor son similares. Conocer estos parámetros es necesario de cara a una correcta gestión de esta especie en un futuro.[Abstract] In this work the reproductive success and the invasive potential of different samples of the species Helychrisum petiolare Hilliard & Burtt, belonging to different populations, all located within the Gulf Ártabro is evaluated. We analyze two populations with many individuals who play the role of mother populations, and 4 isolated populations, in order to determine whether this species has an effective sexual reproduction, in addition we also determine if in isolated populations occurs depression isolation, or conversely, their reproductive success and invasive potential are similar. Knowing these parameters is necessary to face the proper management of this species in the future.Traballo fin de grao (UDC.CIE). Bioloxía. Curso 2015/201

La noción de predicción matemática en situaciones variacionales. Un estudio de construcción de discurso

En este escrito se reporta la forma en que el gesto y la interacción entendida en un sentido sensorial, forman parte de un discurso matemático construido en el contexto de una actividad predictiva. Se describe cómo el gesto y la interacción pueden favorecer –mediar– la predicción matemática en las personas

Emergence time and skin melanin spot patterns do not correlate with growth performance, social competitive ability or stress response in farmed rainbow trout

In wild salmonid fish, specific individual behavioral traits have been correlated with the timing of fry emergence from their gravel spawning nests; Early emerging fish display more aggressive behavior and have a higher probability of becoming socially dominant, compared to fish that emerge at a later stage. Apart from aggression and dominance, other behavioral and metabolic traits, such as boldness, metabolic rate, or growth, have also been linked to emergence time. Altogether, the traits of early- and late-emerging fish resemble those of the proactive and reactive stress-coping style, respectively. As proactive fish are considered more resilient to stress, it may be desirable to select these for aquaculture production. However, it is currently unclear to what extent the link between emergence time and stress-coping styles is maintained in the selective breeding of farmed fish. In the present study, eyed eggs from a commercial supplier were hatched, and larvae fractionated according to their emergence time. Later on, juvenile fish from different emergence fractions were subjected to a stress challenge and also tested to evaluate their competitive ability for food. Beyond some slight dissimilarities in the acute stress responses, emergence fraction displayed no correlation with growth rates, or the ability to compete for feed. Within the whole group of fish utilized in the experiments, no relationship between skin melanin spot pattern and growth performance, stress response intensity, or competitive ability was found. Altogether, the differences in physiological traits related to emergence time were not as strong as those found in earlier studies. It is hypothesized, that the origin and degree of domestication of the fish might be partly responsible for this. The predictive value of skin spots or emergence time to infer the fish stress coping style in farmed fish is also discussed

Dietary Tryptophan Induces Opposite Health-Related Responses in the Senegalese Sole (Solea senegalensis) Reared at Low or High Stocking Densities With Implications in Disease Resistance

High 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. In an attempt to overcome deleterious effects of chronic stress, Senegalese sole, Solea senegalensis, held at low (LD) or high density (HD) were fed tryptophan-supplemented diets with final tryptophan content at two (TRP2) or four times (TRP4) the requirement level, as well as a control and non-supplemented diet (CTRL) for 38 days. Fish were sampled at the end of the feeding trial for evaluation of their immune status, and mortalities were recorded following intra-peritoneal infection with Photobacterium damselae subsp. piscicida. Blood was collected for analysis of the hematological profile and innate immune parameters in plasma. Pituitary and hypothalamus were sampled for the assessment of neuro-endocrine-related gene expression. During the feeding trial, fish fed TRP4 and held at LD conditions presented higher mortalities, whereas fish kept at HD seemed to benefit from this dietary treatment, as disease resistance increased over that of CTRL-fed fish. In accordance, cortisol level tended to be higher in fish fed both supplemented diets at LD compared to fish fed CTRL, but was lower in fish fed TRP4 than in those fed TRP2 under HD condition. Together with lower mRNA levels of proopiomelanocortin observed with both supplementation levels, these results suggest that higher levels of tryptophan might counteract stress-induced cortisol production, thereby rendering fish better prepared to cope with disease. Data regarding sole immune status showed no clear effects of tryptophan on leucocyte numbers, but TRP4-fed fish displayed inhibited alternative complement activity (ACH50) when held at LD, as opposed to their HD counterparts whose ACH50 was higher than that of CTRLfed fish. In conclusion, while dietary tryptophan supplementation might have harmful effects in control fish, it might prove to be a promising strategy to overcome chronic stress-induced disease susceptibility in farmed Senegalese sole

Estudio comparativo sobre la traducción del lenguaje no verbal del chino y dos versiones en español : el caso de la novela Xi You Ji /

En la presente tesis, se examina la traducción del lenguaje no verbal del chino al español en dos versiones del Xi You Ji. El marco teórico-metodológico usado en esta tesis combina de modo interdisciplinar un enfoque lingüístico-literario con otro más traductológico. Por una parte, hemos usado dos de las cuatro categorías propuestas por Poyatos (1994) para estudiar las funciones semiótico-comunicativas de los elementos no verbales de los personajes de ficción. Por la otra, hemos adoptado cuatro de las diez categorías que utiliza Korte (1997) para explicar las funciones y los efectos literarios del lenguaje corporal en el texto narrativo. Finalmente, hemos aportado nuestra propia clasificación dividiendo las técnicas de traducción de los elementos no verbales en cuatro categorías, en función de si se traslada o no el mismo gesto y de si se transmite o no su significado. En concreto son: a) traducción del gesto del original por el mismo gesto manteniendo el significado original; b) traducción del gesto del original por el mismo gesto perdiendo el significado original; c) traducción del gesto del original por otro gesto manteniendo el significado original; y d) traducción del gesto del original por otro gesto perdiendo el significado original (incluyendo la reducción u omisión). La tesis consta de cuatro capítulos: en el primero, presentamos nuestro objeto de estudio, la novela Xi You Ji de Wu Cheng'en; en el segundo, exponemos el marco teórico para nuestro trabajo; en el tercero, ofreceremos distintos ejemplos del lenguaje no verbal en Xi You Ji para analizar su papel literario; finalmente, en el último capítulo, comparamos las técnicas de traducción empleadas en las dos versiones del Xi You Ji al español. Con este trabajo, esperamos haber contribuido a un campo de estudio relativamente poco explorado: el del lenguaje no verbal en la traducción y en la literatura y, especialmente, en el caso de la traducción chino-español.This thesis examines the nonverbal language translation from Chinese to Spanish of Xi You Ji in two Spanish versions. The theoretical and methodological framework used in this thesis combines the literary-language and another kind of translation, Interdisciplinary approach. First, we had used two of the four categories proposed by Poyatos (1994) to study the semiotic-communicative functions of nonverbal elements of the fictional characters. On the other hand, we had adopted four of the ten categories used by Korte (1997) to explain the functions and literary effects of body language in the narrative. Finally, we have provided our own classification dividing the techniques of translation of the nonverbal elements into four categories, based on whether or not to move the same gesture and whether or not to transmit meaning. Specification: a) The translation of the original act maintains the same gesture and keeps the original meaning; b) The translation of the original act with the same gesture loses its original meaning; c) The translation of the original gesture, by using another gesture, keeps the original meaning; d) The translation of the original gesture, by using another gesture (including the reduction or omission), loses the original meaning. The thesis consists of four chapters: In the first, we present our object of the study, the novel Xi You Ji, written by Wu Cheng'en; in the second, we present the theoretical framework for our work; in the third, we offer different examples of nonverbal language in Xi You Ji to analyze literary roles; finally, in the last chapter, we have compared the translation techniques used in these two Spanish versions of Xi You Ji. With this work, we hope that we have made the contribution to an unexplored study field, the non-verbal language in translation and literature, and especially in the case of Chinese-Spanish translatio

Lourdeur de texte et féminisation

Dans notre étude, nous avons testé l’idée, avancée par l’Académie française (2002), que la féminisation du langage alourdissait le texte. Pour cela, nous avons fait lire à 40 étudiantes et étudiants cinq descriptions de différentes professions. Pour chacune de ces professions, quatre descriptions différentes ont été rédigées: une version avec la profession au masculin, une avec la profession au féminin et deux versions avec la profession sous formes épicènes. La vitesse de lecture des descriptions de professions sous une forme épicène ou féminine, même si celleci était plus lente à la première occurrence du nom de métier, retrouvait son rythme normal, ceci dès la deuxième occurrence, indiquant un effet d’habituation. Les résultats indiquent par ailleurs que la féminisation des noms de métiers ne joue pas de rôle quant à la valorisation ou la dévalorisation de ces métiers.In this paper, we tested the idea, raised by the Académie française (2002), that writing role names in both masculine and feminine forms would hinder reading. We presented 40 participants with different texts focused on several professions. The role names were written in one of four grammatical forms : masculine, feminine, or one of two epicène forms (i.e., mécanicien-ne-s or mécaniciens et mécaniciennes). Our study shows that although reading speed was slower on the first encounter of the role names when written in the epicène and feminine form, on the second and third encounter, the speed reached a normal reading speed, suggesting a rapid habituation effect. We also did not find any hint of devaluation of the role names due to the grammatical form of the role names