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- Are personality traits consistent in fish? The influence of social contextPublication . Castanheira, Maria Filipa; Cerqueira, Marco; Millot, Sandie; Gonçalves, Rui A.; Oliveira, Catarina C. V.; Conceição, Luis E. C.; Martins, Catarina I. M.Individual differences in behavioural and physiological responses to challenges are progressively accepted as adaptive variation and reveal a strong degree of evolutionary conservation throughout the vertebrate taxa. Previous studies in gilthead seabream (Sparus aurata) suggested that individual differences in behaviour reflect distinct coping styles or personality, contrasting consistent traits associations. One of the traits that have been shown to be consistent over time and across context is the escape response under a restraining test. Using this trait as a proxy of personality in seabream the influence of social context in the consistency of escape behaviour was investigated. Individually tagged juvenile seabream (n = 360; 70.18 +/- 11.44 g; mean +/- SD) were subjected to a restraining test that consisted of keeping each fish in an emerged net for one minute. Behaviours measured in the net (latency to escape; number of escape attempts and total time spent on escaping) were collapsed into first principal component scores using Principal Components Analysis (PCA). Using the PCA scores the individuals were distributed into homogeneous groups (n = 30 each group) of proactive, reactive and intermediate. Control groups consisted of mixed groups with 1/3 of each coping style. After one month the same individuals were exposed to the same test (restraining test) to assess consistency of behavioural responses. Results indicate that homogenous groups of proactive (p = 0.086) and reactive (p = 0.159) individuals did not exhibit consistent behavioural responses as opposed to the intermediate (p = 0.028) and control groups (p < 0.001). This study thus confirms that the social context in which fish are kept significantly influence personality traits. (C) 2016 Elsevier B.V. All rights reserved.
- Preliminary results on the daily and seasonal rhythms of cuttlefish Sepia officinalis (Linnaeus, 1758) locomotor activity in captivityPublication . Oliveira, Catarina; Grano-Maldonado, Mayra; Gonçalves, Rui A.; Frias, Paulo; Sykes, António V.Cephalopods are considered as an alternate group for aquaculture species diversification [1,2], not only because they are a good food source (highly appreciated in some worldwide markets, e.g., Portugal, Spain, Italy and Asia) and have the potential to quickly reach a market size, but also because they are considered animal models in several fields of research [3–5], and it is expected that such models are progressively obtained from bioteriums instead of being captured from nature. Despite the recent advances in culture protocols of several cephalopod species [2], there is still little information available about the biological rhythms of cephalopods in captivity. In fact, to the best of our knowledge, there are only 4 published papers concerning this theme, and these are focused on octopus species [6–9]. This issue assumes increasing importance with the enforcement of EU welfare legislation (Directive 2010/63/EU), and this information is critical for the future update of Annex III (housing conditions) for cephalopods of that Directive, and for a future update of the Guidelines for the Care and Welfare of Cephalopods in Research [10]. If it is considered that the European cuttlefish Sepia officinalis (Linnaeus, 1758) may have, at the least, two different sleep‐like states [11], the importance of this study becomes even more evident.
- Directive 2010/63/EU on animal welfare: a review on the existing scientific knowledge and implications in cephalopod aquaculture researchPublication . Sykes, António V.; Baptista, Filipa D.; Gonçalves, Rui A.; Andrade, José PedroThis review intends to provide a reflection regarding Directive 2010 ⁄ 63 ⁄ EU, on animal welfare, and its application concerning cephalopod breeding and experimentation in aquaculture research. To do so, we gathered different perspectives of our group members, involving two cephalopod aquaculture researchers, an aquaculture fish production technician and a veterinary professional, the latter with no background on cephalopod research. The inclusion of this class in the animal welfare legislation; the definition of live cephalopods, stress, pain and suffering are revised according to the latest scientific knowledge. Considering the 15 year background that the Centre of Marine Sciences holds on the cultivation of the European cuttlefish, an evaluation of existing production protocols, aquaculture technology related research, ethics and cephalopod welfare are discussed. The application of anaesthesia, analgesia and euthanasia is discussed, bearing in mind the different procedures applied on a daily basis in aquaculture breeding and experimentation and the requirements of the new Directive. Finally, an overview of the above and progress on 3Rs (replacement of animals, reduction in number of animals and refinement of procedures) application to cephalopod welfare is presented.
- Preliminary results on light conditions manipulation in Octopus vulgaris (Cuvier, 1797) paralarval rearingPublication . Garrido, Diego; Reis, Diana; Orol, Diego; Gonçalves, Rui A.; Martín, M.; Sykes, António V.; Rodríguez, Covadonga; Felipe, Beatriz; Zheng, Xiaodong; Lagos, Luis; Almansa, EduardoHigh paralarvae mortality is a major bottleneck currently hindering the control over the lifecycle of common octopus (Octopus vulgaris Cuvier, 1797). It is believed that this problem might be related to either zoo-technical and/or nutritional aspects. The present paper is focused on the study of different zoo-technical aspects related to light conditions on the rearing of paralarvae, including the effects of polarization in prey ingestion, the use of a blue filter to simulate natural conditions, and the use of focused light to avoid reflections of the rearing tank’s walls. In the first experiment, O. vulgaris paralarvae ingestion of Artemia sp. and copepods (Tisbe sp.) was assessed under either normal or polarized light. In the second experiment, the effect of a blue filter with natural light or focused artificial light on growth and mortality was assessed over 15 days of rearing. Ingestion rate was not influenced by light polarization. Nonetheless, a significantly higher ingestion of Artemia sp. with respect to copepods was observed. The blue filter promoted the use of natural light conditions in Octopus paralarval culture, while focused light reduced the collision of the paralarvae against the walls. However, no significant differences were found in paralarval growth nor survival.
- Characterization of deformed hatchlings of Octopus vulgaris obtained under captivity from a small femalePublication . Jiménez-Prada, Pablo; Scherbakova, Anastasia; Riera, Rodrigo; Felipe, Beatriz C.; Sykes, António V.; Gonçalves, Rui A.; Andrade, José Pedro; Perales-Raya, Catalina; Rodríguez, Covadonga; Almansa, EduardoThe common octopus (Octopus vulgaris), a promising species for aquaculture, spawns easily under cap-tivity from mature females (usually above 1 kg wet weight). Octopus juveniles and adults are collectedfrom nature to obtain eggs and paralarvae for aquaculture development trials. In July 2011, a very smallfemale (150 g wet weight but with an age estimation of 300 days-old) spawned almost 77,000 paralar-vae. Malformations of paralarvae were noticed in the first spawning days, namely the absence of arms.Despite not being lethal, these abnormalities might be derived from the physiological condition of thebreeding specimen (the female’s lower weight to the estimated amount of living days), which might beeventually related to nutritional unbalances or genetic parameters that were transferred to the eggs.
- Early weaning of cuttlefish (Sepia officinalis, L.) with frozen grass shrimp (Palaemonetes varians) from the first day after hatchingPublication . Sykes, António V.; Gonçalves, Rui A.; Andrade, José PedroThe European cuttlefish (Sepia officinalis) is one of the most well-known cephalopods (Boletzky 1983). During the last years, research on cuttlefish has focused on its introduction as a new species for aquaculture. This is due to the biological and economical characteristics that this species display, which have the potential for industrial culture. The most important are the short life cycles and the fast growth rates which imply lower production periods and associated costs. On the other hand, the inability to grow cephalopods on an inexpensive and storable prepared diet has been identified as a bottleneck (Sykes, Domingues, Correia & Andrade 2006).
- Determination of dietary docosahexaenoic acid (DHA) requirements for senegalese sole (Solea senegalensis) post-larvaePublication . Gonçalves, Rui A.; Conceição, L. E. C.; Martins, Dulce AlvesDocosahexaenoic acid (DHA) is an essential fatty acid for marine fish larvae, with effects on growth and larval quality. DHA requirements for Senegalese sole (Solea senegalensis), a species of high commercial interest, are poorly understood. On this thesis a dose–response design in conjunction with a methodology based on tube feeding of 14C-[DHA], was employed in order to determine the dietary DHA requirements for Senegalese sole post-larvae. The effect of dietary DHA was examined on growth, survival, pigmentation and Artemia intake (at low light conditions). From 22 to 35 days after hatching (DAH) - pre-weaning period - post-larvae were fed frozen Artemia that had been enriched using one of four experimental emulsions containing four graduated concentrations of DHA. Final levels of DHA in the enriched Artemia metanauplii were 0.0 mg g-1DW (DHA-0), 5.1 mg g-1DW (DHA-5), 14.1 mg g-1DW (DHA-14) and 30.2 mg g-1DW (DHA-30). Afterwards and during the weaning period (41 to 61 DAH) all post-larvae were fed with a same moist feed. Significant differences in dry weight (DW) were found at the end of the pre-weaning period. Treatment DHA-0, induced a higher larval growth (2.84±1.04 mgDW) than treatment DHA-5 (2.38±0.74 mgDW). Light intensity influenced both final DW and RGR and there was a positive correlation for a higher growth (DW and RGR) as the light intensity increased. On weaning period treatments DHA-0 and DHA-30 showed significant higher DW and total length values than those presented in DHA-5 and DHA-14. On the radiolabelled Artemia intake test, and after 30 min in presence of Artemia (T30), larvae ingested significantly higher amounts than observed at 10 min, and a positive correlation between dietary DHA levels and Artemia fed within the T10 groups was also found. Tube feeding of [1- 14C]DHA resulted in no significant differences for absorption, retention and catabolism between larvae submitted to different experimental treatments. However, a slight tendency for an increase in the percentage of catabolised DHA with increased DHA dietary supply was also noted, with an apparent increase in catabolism between treatment DHA-5 and DHA-14. No major effects of dietary DHA levels ranging from 0.0 to 30.2 mg.g-1Artemia DW between 22 and 35DAH could be observed on larval performance. However, light intensity probably had an impact on post-larvae performance, mainly at high intensities. Furthermore, the tube feeding trial suggested a possible DHA requirment between 5.1 and 14.6 mg g-1 of Artemia dry weight.
- The use of different anaesthetics as welfare promoters during short-term human manipulation of European cuttlefish (Sepia officinalis) juvenilesPublication . Gonçalves, Rui A.; Aragão, C.; Frias, P. A.; Sykes, António V.Anaesthetics are frequently used to prevent injuries, stress and to promote welfare while handling animals. The efficiency of five anaesthetics for short-term handling of the European cuttlefish (Sepia officinalis) was tested in order to determine the best agent and its concentration. Ethanol (10.0, 20.0 and 30.0 mL.L−1 ), clove oil (0.05, 0.15 mL.L−1 ), hypothermia (8 °C), magnesium chloride (hexahydrated; 20.0, 27.0 g.L−1 ) and AQUI-S® (10.9 μl.L−1 ) were the selected anaesthetics. This choice was preceded by a preliminary trial, with additional agents, where 2-phenoxyethanol (10, 15, 20, 30 mL.L−1 ) and MS-222® (30, 40 mg.L−1 ) were used.
- Refining tools for studying cuttlefish ( Sepia officinalis ) reproduction in captivity: in vivo sexual determination, tagging and DNA collectionPublication . Sykes, António V.; Alves, Alexandra; Capaz, Juan Carlos; Madeira, Céline; Couto, Ana T.; Gonçalves, Rui A.; Frias, Paulo A.; Leal, Irene; Andrade, José PedroTo overcome the bottleneck of reproduction in cuttlefish, Sepia officinalis, aquaculture development, there is need for new tools or refinement of methods. While attaining low welfare impact on individuals, procedures to allow for in vivo individual sexual and maturity determination, tagging and collection of samples for high quality DNA are needed. The present study evaluated the use of an endoscope, visual implant elastomer and swabbing for each, respectively, in a set of 3 experiments that registered its effects on growth, mortality and reproduction. Results showed that all the methodologies tested herein were of easy application, did not promote injuries nor poor growth, abnormal reproduction or increased mortality. This indicates that cuttlefish would not be experiencing pain, suffering, distress and lasting harm (PSDLH), resulting from the application of these procedures and that these are therefore recommended as new standards for reproduction studies in the species.