Optimizing rearing and welfare in Senegalese sole (Solea senegalesensis) broodstock: effect of ambient light intensity and handling time on stress response

Broodstock rearing conditions and handling procedures should be optimized in aquaculture species in order to benefit fish welfare and guarantee optimal conditions for spawning. In teleosts, basal cortisol levels display daily rhythms, oscillating along the 24 h of the day. In this sense, handling fish at different moments of the day may lead to different stress responses. The present study aimed at investigating the optimal rearing conditions for Senegalese sole broodstock, considering ambient light intensity and handling time. The optimal light intensity (50, 100 or 200 lx) was investigated by measuring fish cortisol levels and monitoring locomotor activity rhythms under each intensity tested. Results showed a significant increase in cortisol levels of fish exposed to 200 lx, when compared to values obtained under 100 lx, accompanied by changes in locomotor activity rhythms in both tanks under study. These results suggested that 200 lx may be too high as light intensity for this species, whereas 100 lx seems to be more adequate. Also, daily rhythms of stress response were investigated in breeders from different origins (Wild and first generation, G1). Basal cortisol levels and cortisol stress response after an acute stressor (air exposure) were monitored at two distinct moments of the day (Mid-Light and Mid-Dark). Basal levels were higher during the day in the wild group, while G1 fish seemed to have lost the daily fluctuations in basal cortisol plasma levels, as well as their daily rhythms of locomotor activity. Both groups showed lower stress responses during night-time, an indication that this is an adequate period of the day to handle this species. Senegalese sole breeders born in captivity presented more pronounced stress responses when compared to wild fish, reflecting their different life history in terms of stress challenges.FP7/SME/2008/1; UID/Multi/04326/2019; DL 57/2016/CP1361/CT0007; DL 57/2016/CP1361/CT0033info:eu-repo/semantics/publishedVersio

Supplementing taurine to plant-based diets improves lipid digestive capacity and amino acid retention of Senegalese sole (Solea senegalensis) juveniles

Recent studies reported positive effects of taurine supplementation to plant protein-based diets on fish growth performance and feed conversion ratio but the mechanisms involved remain unclear. The objective of this work was to provide a first insight on the importance of taurine on dietary protein and lipid absorption and utilisation, in Senegalese sole (Solea senegalensis) juveniles fed plant-based diets. Seven practical diets were tested: a fishmeal-based diet (FM) and a plant protein-based formula (PP85) to which taurine was added in graded levels: 0.2% (TAU1), 0.3% (TAU2), 0.4% (TAUS), 0.7% (TAU4) and 1.5% (TAU5). Short-term metabolic trials were performed by tube-feeding the different experimental diets labelled with different tracers: C-14-taurine, C-14-triolein (as tracer of dietary triacylglycerol) and a mixture of C-14-amino acids. Feeding sole juveniles with the PP85 diet affected taurine metabolism, since a higher proportion of dietary taurine was directed to gallbladder and probably used for bile salt synthesis. Consistent with this, fish receiving the plant-based low taurine-content diets (PP85 and TAU1) displayed a poor triacyglycerol digestion capacity. A higher proportion of C-14-amino acids was retained in fish muscle when fed the TAU5 compared to the PP85 diet. These short-term trials suggested that taurine supplementation to a plant-based diet might be beneficial to sole performance by enhancing bile salt synthesis and triacylglycerol digestion as well as muscle amino acid retention. However, this dietary supplementation should be tested in long-term trials to verify the effect on fish growth and to assess the beneficial effects on protein and lipid metabolism suggested here. Statement of relevance in the general field of aquaculture (limited to 60 characters): Adding taurine to a plant-based diet is beneficial for sole (C) 2016 Elsevier B.V. All rights reserved.National Funds through Fundacao para a Ciencia e Tecnologia [PTDC/MAR/117047/2010]Fundacao para a Ciencia e Tecnologia, Portugal [SFRH/BDP/65578/2009]info:eu-repo/semantics/acceptedVersio

Regulatory Reform Of The Urban Bus System In Recife (Brazil): Stakeholders And The Constituency-Building Process

The integrated metropolitan administration of the bus system in Recife is almost thirty years old and has survived a number of different perils. Even the most recent municipal administration of the city of Recife has dropped its plan to bring back the management of the municipal lines under its roof and has accepted cooperating with the State Government of Pernambuco, provided that a new cooperation contract basis is adopted. This paper begins with an explanation of the administrative and operator structure of the Metropolitan Recife bus system, which has been run by the Metropolitan Urban Transportation Company of Recife (EMTU - Empresa Metropolitana de Transportes Urbanos do Recife), a public corporation owned by the state of Pernambuco, but actually an administrative autarchy. Despite its success in ensuring coordination on the entire metropolitan level, which is still a rare example in Brazil, the EMTU has not been able to ensure a competitive environment in the bus industry under its control and the sector has been following a continuous path in direction of area-based monopolies. This paper describes this process as well as the different attempts by the EMTU to introduce benchmark regulation and the reaction of the operators against such attempts. In spite of these efforts, the legal expiration of the contracts and the organization of the legally required tendering procedure have been subsequently postponed. Different tender studies have been prepared and have been subsequently dropped. When the current municipal administration of the City of Recife came to power, a tender procedure was promised and expected, but the city government only managed to regulate (actually repress and substantially quell) the local informal operators. Most recently, the state attorney has pressed the state and municipal authorities to organize the procedure, but response is still slow. This paper describes these studies and the reactions of different stakeholders (operators, public servants, politicians, consultants, attorneys, press and the population) throughout this long process towards the tender procedure and also outlines the recent negotiations for reforming the EMTU.Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne

Amino acid metabolism in gilthead seabream is affected by the dietary protein to energy ratios

The dietary protein to energy ratio (P/E) has proven to influence protein utilization and/or growth in several fish species. This study intended to unravel the bioavailability and metabolic fate of lysine and methionine in gilthead seabream (Sparus aurata) juveniles fed plant diets with different P/E ratios. Seabream juveniles were fed two isonitrogenous diets (45% crude protein) differing in crude lipids (20 and 14%): LowP/E (P/E ratio=20.0 mg protein kJ-1) and HighP/E (P/E ratio=21.4 mg protein kJ-1). After three weeks, fish (11.6 +/- 4.3 g) were tube-fed the respective diet labelled with C-14-protein (L-amino acid mixture), C-14-lysine, or C-14-methionine. Protein, lysine, and methionine utilization were determined based on the proportion of C-14-amino acid evacuated, retained in the free or protein-bound fraction of liver and muscle, or catabolized. This study revealed that a decrease in P/E ratio resulted in lower amino acid evacuation (p < 0.05), contributing to a more efficient amino acid uptake. Results indicate that amino acids are retained as protein in the liver and not only temporarily available in the free pool. The amount of free amino acids retained in the muscle of LowP/E fed fish was significantly higher than in HighP/E fish (p < 0.05) due to a simultaneous higher retention of lysine and methionine, without affecting the overall protein retention. Methionine catabolism was significantly lower than lysine or protein independently of the P/E ratio (p < 0.05), reinforcing that this amino acid is preferentially spared for metabolic functions and not used as energy source. In contrast, increasing the dietary P/E ratio decreased lysine catabolism and increased its availability for growth. The bioavailability and metabolism of individual amino acids should be considered when optimizing P/E ratios in diets for gilthead seabream juveniles. Formulating diets with optimum P/E ratios will improve diet utilization and fish performance.info:eu-repo/semantics/publishedVersio

CARTOGRAFIA DOS GRUPOS DE PESQUISA DA UNEB: ARTICULANDO REDES DE DIFUSÃO DO CONHECIMENTO NA UNIVERSIDADE

Este texto é fruto de reflexões e inquietações da pesquisa de doutorado em andamento que apresenta como questão central: que redes são estabelecidas pelos grupos de pesquisa certificados da UNEB, a partir dos seus processos comunicacionais, tendo em vista a difusão do conhecimento na universidade? A pesquisa tem como princípios epistemológicos, a multirreferencialidade e o rizoma. Optamos pela abordagem qualitativa de pesquisa e, como método a cartografia que possibilitará perceber relações comunicacionais que se estabelecem e são tensionadas nos grupos de pesquisa, com o intuito desvelar as redes de difusão do conhecimento. Ainda não temos resultados, pois a pesquisa se encontra em desenvolvimento, apresentaremos aqui as primeiras reflexões sobre os princípios epistemológicos e metodológicos e as percepções e achados desta caminhada, ainda em construção

Metabolic fate is defined by amino acid nature in gilthead seabream fed different diet formulations

The sustainability of the Aquaculture industry relies on optimising diets to promote nitrogen retention and maximise fish growth. The aim of this study was to assess how different dietary formulations influence the bioavailability and metabolic fate of distinct amino acids in gilthead seabream juveniles. Amino acids (lysine, tryptophan, and methionine) were selected based on their ketogenic and/or glucogenic nature. Seabream were fed practical diets with different protein (44 and 40%) and lipid contents (21 and 18%): 44P21L, 44P18L, 40P21L, and 40P18L. After three weeks of feeding, the fish were tube-fed the correspondent diet labelled with 14C-lysine, 14C-tryptophan, or 14C-methionine. The amino acid utilisation was determined based on the evacuation, retention in gut, liver, and muscle, and the catabolism of the tracer. The metabolic fate of amino acids was mainly determined by their nature. Tryptophan was significantly more evacuated than lysine or methionine, indicating a lower availability for metabolic purposes. Methionine was more retained in muscle, indicating its higher availability. Lysine was mainly catabolised, suggesting that catabolism is preferentially ketogenic, even when this amino acid is deficient in diets. This study underpins the importance of optimising diets considering the amino acids’ bioavailability and metabolic fate to maximise protein retention in fish.info:eu-repo/semantics/publishedVersio

Turismo académico no Porto: o caso dos estudantes de mobilidade internacional

Dissertação de mestradoO aumento da mobilidade estudantil na Europa tem suscitado a realização de muitos estudos nesta área, os quais se têm focado nos fatores de motivação para a escolha de destinos ou no resultado das experiências de mobilidade. No entanto, menos atenção tem sido dada ao turismo académico e suas repercussões, um setor em expansão nos últimos anos. A temática da presente investigação incide sobre o turismo académico e procura compreender a relação entre este e as mobilidades internacionais, bem como a influência deste tipo de turismo na imagem de Portugal como destino de mobilidade. A literatura sugere que os estudantes de mobilidade têm comportamentos semelhantes a turistas. Além disso, estes dinamizam as economias locais, recomendam os destinos e influenciam a atratividade das universidades. Assim, tornou-se pertinente estudar Portugal como destino de mobilidade e as possíveis consequências a nível turístico do crescimento estudantil internacional no país. Para tal, esta investigação utilizou a cidade do Porto como unidade de análise do estudo de caso, recorrendo a uma metodologia mista, através da utilização de entrevistas semiestruturadas e inquéritos por questionário. Foram entrevistadas cinco Instituições de Ensino Superior (IES) do Porto e o questionário foi aplicado a 803 estudantes de mobilidade internacional na cidade. A análise de dados qualitativos recolhidos foi efetuada utilizando a técnica de análise Grounded Theory, e os dados quantitativos através do recurso ao programa do SPSS versão 24 (Statistical Package for Social Sciences). Os resultados obtidos constatam altos níveis de satisfação com a mobilidade no Porto, mas com espaço para melhorias. O estudo indica que existe uma relação forte entre mobilidades internacionais e turismo académico e que as experiências turísticas podem influenciar a imagem de Portugal como destino de mobilidade, especialmente através de recomendação boca-a-boca. Verificou-se também que as oportunidades de desenvolvimento de parcerias das IES com entidades e associações turísticas locais ainda podem ser mais exploradas, através de uma estratégia agregada dos stakeholders do Porto de forma a melhorar a viii promoção da cidade como destino de mobilidade internacional e também a satisfação dos estudantes com as atividades realizadas. Esta pesquisa contribui com informação pertinente para a formulação de políticas de turismo por entidades locais e IES, que possam desenvolver estratégias conjuntas para trabalhar com futuros estudantes de mobilidade internacional e, simultaneamente, turistas no país.The increase of student mobility in Europe has led to the carrying out of many studies in this area, which have focused on motivating factors for choosing destinations or on the outcome of mobility experiences. However, less attention has been paid to academic tourism and its repercussions, an expanding sector in recent years. The topic of this research focuses on academic tourism and seeks to understand its relationship with international mobility, as well as the influence of this type of tourism on the image of Portugal as a mobility destination. The literature suggests that mobility students are beginning to resemble to tourists. They dynamize local economies, recommend destinations and influence the attractiveness of universities. Thus, it became pertinent to study Portugal as a mobility destination and the possible consequences in terms of tourism of this international student growth in the country. To this end, this investigation uses the city of Porto as the unit of analysis of the case study, using a mixed methodology with semi-structured interviews and questionnaires. Five Higher Education Institutions (HEIs) from Porto were interviewed and the questionnaire was provided to 803 international mobility students. The analysis of collected qualitative data was performed using the Grounded Theory technique, and the quantitative data was carried out using the SPSS version 24 (Statistical Package for Social Sciences). The results obtained show high levels of satisfaction with mobility in Porto, but with room for improvement. The study indicates that there is a strong relationship between international mobility and academic tourism, and that tourist experiences may influence the image of Portugal as a mobility destination, especially through word-ofmouth recommendation. It was also found that the opportunities for developing partnerships between HEIs with local entities and associations can be further explored, through an aggregated strategy of Porto stakeholders to improve the promotion of the city as an international mobility destination and the satisfaction of students with carried out activities. This research contributes with relevant information for tourism policy making by local entities and HEIs, which can develop joint strategies to work with future mobility students who are, simultaneously, tourists in the country

La composition en acides aminés, dans le régime alimentaire des larves de daurade royale, affecte-t-elle leur performance ?

7 páginas, 2 figuras, 4 tablas.[EN] Live preys commonly used in fish larval rearing seem to be imbalanced in terms of amino acids. Manipulation of their amino acid composition is difficult, but the use of microencapsulated diets allows this manipulation. This study analysed the effect of amino acid supplementation, in order to compensate for dietary amino acid imbalances, on growth and survival of gilthead seabream (Sparus aurata) larvae. Larvae were reared until 32 days after hatching, in a closed recirculating water system (19 °C), using only live food (rotifers and Artemia). Thereafter, larvae were fed Artemia or one of the experimental microencapsulated diets: supplemented with indispensable amino acids (IAAsup diet), or supplemented with dispensable amino acids (DAAsup diet). Experiment lasted for 10 days. Dietary supplementation with indispensable amino acids resulted in A/E ratios [(each indispensable amino acid) × (total indispensable amino acids)−1 × 1000] more similar to the ones of larval seabream and in higher IAA:DAA ratios than in the DAAsup diet. Survival was similar in larvae fed the IAAsup diet (75%) or Artemia (87%), but was significantly lower in larvae fed the DAAsup diet (52%). Larvae from all treatments more than doubled their average dry weight during the experimental period. Final dry weight was similar in larvae fed both microcapsules, but these were lighter than larvae fed with Artemia. Relative growth rate (RGR) and total biomass production tended to be higher in larvae fed the IAAsup (RGR = 9% day−1) than the DAAsup diet (RGR = 7.5% day−1) and only in this last treatment these parameters were significantly lower than in larvae fed with Artemia. Therefore, dietary supplementation with indispensable amino acids resulted in a more balanced dietary amino acid profile, which significantly increased survival. Further studies introducing microdiets earlier in the development seem necessary in order to optimise growth.[FR] Les proies vivantes utilisées dans les élevages larvaires semblent déséquilibrées en terme d'acides aminés. Manipuler la composition en acides aminés est difficile mais l'usage d'aliments encapsulés le permet. Cette étude analyse l'effet d'une supplémentation en acides aminés sur la croissance et la survie des larves de daurade royale (Sparus aurata) afin de compenser un déséquilibre. Les larves sont élevées jusqu'à 32 jours après éclosion en circuit fermé (eau à 19 °C), en utilisant des aliments vivants uniquement (rotifères et Artemia). Les larves sont ensuite nourries avec des Artemia ou bien avec des aliments microencapsulés expérimentaux, supplémentés en acides aminés soit indispensables (régime IAAsup) soit non-indispensables (régime DAAsup). La durée de l'expérience est de 10 jours. La supplémentation en acides aminés indispensables conduit à des ratios A/E [(chaque AA indispensable) × (total en AA indispensables)−1 × 1000] plus proches de ceux de la larve de dorade et des ratios IAA/DHA plus élevés que ne le fait la supplémentation en acides aminés non-indispensables. Le taux de survie est similaire chez les larves nourries avec le régime IAAsup (75 %) ou Artemia (87 %) mais inférieur significativement chez les larves soumises au régime DAAsup (52 %). Le poids sec moyen de ces larves, quel que soit leur régime alimentaire, a doublé durant la période expérimentale. Le poids sec est similaire chez les larves nourries de microcapsules mais moins élévé chez celles nourries d'Artemia. Le taux de croissance relative (RGR) et la production de biomasse totale tendent à être plus élevés chez les larves nourries en IAAsup (RGR = 9 % jour−1) que celles nourries en DAAsup (RGR = 7,5 % jour−1). C'est seulement dans ce dernier traitement que les paramètres sont plus faibles significativement que chez les larves nourries d'Artemia. Ainsi, les supplémentations alimentaires en acides aminés indispensables peuvent augmenter la survie. D'autres études, introduisant des micro-aliments de façon plus précoce dans le développement, semblent nécessaires afin d'optimiser la croissance.The authors acknowledge funding by project AGL2004-06669-C02-01 (MCYT, Spain) and grant SFRH/BPD/14835/2003 (FCT, Portugal).Peer reviewe

Parental and early-feeding effects of dietary methionine in rainbow trout (Oncorhynchus mykiss)

We studied the effect of changes in dietary methionine (Met) supply in broodstock and first-feeding rainbow trout fry (offspring). Three plant-based diets differing in Met level (deficient, adequate or in excess of the established requirement) were fed to the broodstock (male and female) for 6 months prior to spawning (diets BD, BA and BE, respectively). The offspring from the parental Met-groups was then challenged in turn with the different Met fry-diets (FD, FA and FE, respectively) for 3 weeks from first-feeding. At spawning, females fed diet BD had significantly higher plasma total and LDL-cholesterol and slightly lower plasma triacylglycerol. Diet BD reduced female (but not male) growth, weight of spawn and egg size, but had no effect on relative fecundity. The free amino acid profile of oocytes was modified, with levels of Met and Cys correlating positively with the Met-levels of broodstock diets. SAM and SAH levels in oocytes followed the same pattern, as opposed to SAM/SAH ratio. At the swim-up stage, no significant effect of parental diet on fry weight was noted, whereas survival was the highest in fry from BE-broodstock. The subsequent 21-day fry feeding with different Met levels highly affected the daily growth index with a significant interaction between the parental-diet and fry-diet effects. The expression of a number of genes regulating sulfur amino acid metabolism was modified either directly by the dietary Met supply in both broodstock liver and in whole fry (e.g. BHMT1, GR, GST pi, MsrA1) or indirectly by the parental Met intakes as seen in the swim-up fry (e.g. BHMT1, MTR, GST pi, MsrA1). Importantly, long-lasting parental effects linked to broodstock Met-intake were seen in the fry, 21-days after first-feeding and irrespective of the fry diet (CTH, MsrA1, MsrB2, SOD2). Similarly, parental effects were noted on the gene expression of both NPY and POMC feeding peptides in fry prior to exogenous feeding which persisted for POMC in the 21-day fry. Parental effects were also demonstrated on the key myogenic gene Myog, on fMHC and GDH in swim-up fry, which persisted for GDH in 21-day fry. In summary, our results demonstrate that dietary Met levels of rainbow trout broodstock affect various traits in the offspring, some of which persisted during the first weeks of exogenous feeding. Further studies need to evaluate the long-term persistence of the parental effects over time and to elucidate the mechanisms, whether epigenetic or not. Statement of relevance: Determining the multiple effects of dietary methionine levels on reproductive, growth performance and metabolism in offspring will help improve formulations of low fish meal feeds for rainbow trout at sensitive life cycle stages. (C) 2016 Elsevier B.V. All rights reserved.EU [288925]F.C.T., Portugal - Fundo Social Europeu (POCH) and National Funds [SFRH/BPD/108389/2015]info:eu-repo/semantics/publishedVersio