Institute of Aquaculture

Mozambique

Institute of Aquaculture

Mozambique

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Villasante S.,University of Santiago de Compostela | Rivero Rodriguez S.,University of Santiago de Compostela | Remiro J.,Spanish Aquaculture Observatory OESA Foundation | Garcia-Diez C.,Spanish Aquaculture Observatory OESA Foundation | And 7 more authors.
Ecosystem Services | Year: 2015

Despite the recognised advantages of rural aquaculture, little research has been done to assess its direct and indirect impacts on food security and poverty mitigation, especially in Africa. The aim of this study is to provide a better understanding of the role of fish-farming systems and their scale, market structure and institutional mechanisms in improving rural aquaculture in Mozambique and Namibia and, consequently, livelihoods and human development in rural communities.This study shows that rural households are strongly dependent on agriculture/aquaculture as their main source of food and income. In general, families making a living from fish farming as their main activity have improved their access to food and basic services. There has been a significant increase in fish consumption in households since they have been engaged in rural fish farming, and there has also been an increase in the frequency of fish consumption per week. This progress in food and nutrition security needs to be consolidated through fish-farming development policies. However, rural aquaculture is still a sector in the early stages of development and has to overcome limiting factors such as a lack of specialised technical knowledge, logistical infrastructure and difficulties in access to credit and markets. © 2015 Elsevier B.V.


Gholami M.,Islamic Azad University at Tehran | Reza Fatemi S.M.,Islamic Azad University at Tehran | Fallahi M.,Institute of Aquaculture | Esmaeili Sari A.,Tarbiat Modares University | Mashinchian A.,Islamic Azad University at Tehran
Life Science Journal | Year: 2013

In this study, we investigated the individual and mixed effects of heavy metals (Cu and Cd) and detergent (LAS) on growth and reproduction of Scenedesmus obliquus algae. We have conducted several tests to determine acute toxicity of pollutants in algae in individual and mixed manners through Selenastrum bottle test method. We used five test samples and a control sample and repeated the tests three times. Concentration ranges were determined by the logarithmic method and finally, the obtained results were calculated by probit analysis and the values of correlation coefficient, EC, and LC (10, 50, and 90) for pollutants were obtained in individual and mixed manners. The results obtained in tests of acute toxicity of algae and values of EC(10, 50 and 90) from the individual effects of heavy metals (Cadmium and Copper), LAS detergent and mixed effects of (Cd and LAS) mixture and (copper and LAS) mixture were, respectively, as the following: Cd(0.068, 0.127, and 0.237), Cu (0.53, 1.5, and 4.24), LAS (10.40, 21.53, and 130), LAS + Cd (0.013, 0.066, and 0.33), LAS + Cu (0.035, 0.21, and 1.32). The obtained allowed limits were 0.0127, 0.15, 2.153, 0.0066, 0.021 mg per liter, respectively, with correlation coefficients of 92, 98, 93, 90 and 95 percent, respectively. According to the non-parametric test of Kruskal-Wallis at 95% of confidence level, we can conclude that, there is no significant difference between copper and mixture of copper and LAS in terms of the effects on algae (P < 0.05). In addition, according to the non-parametric test of Kruskal-Wallis at 95% of confidence level, we can conclude that, there is significant difference between LAS and mixture of LAS and copper in in terms of the effects on algae (P < 0.05).


Fortes N.R.,University of the Philippines in the Visayas | Pinosa L.A.G.,Institute of Aquaculture
Philippine Journal of Science | Year: 2010

The diversity, a univariate measure of both the number of genera present (richness) and their distribution (evenness), of the phytoperiphyton community of a brackishwater pond that received water from a river and the sea was studied during dry and wet seasons. The algal mat ("lab-lab") was sampled when the pond was filled to depths of 5, 10, 15, and 30 cm during 2 and 7 days of submergence to determine the effect of seasons, depth and submergence on the diversity and relate it to the trophic status of periphyton-based pond and quality of "lab-lab" as fish food. Generic diversity and evenness declined with increased depth and colonization time during the dry season but not during the wet season. Richness was affected by depth which was significantly different (p≤0.05) at 2 days submergence, and highly significant (p≤0.01) at 7 days submergence. The index of diversity was moderate ranging from 1.0-3.2 during dry season and 1.2-2.2 during wet season. Richness ranged from 0.7-1.4 during dry season and 0.7-1.0 during wet season. There were low stabilized genera with evenness that ranged from 0.3-0.5 during dry season and 0.2-0.5 during wet season. A more diverse community prevailed during the dry season than during the wet season due to differences in environmental conditions.


Doxa C.K.,Cretaquarium | Doxa C.K.,University of Crete | Sterioti A.,Cretaquarium | Sterioti A.,Institute of Aquaculture | And 3 more authors.
Journal of Biological Research | Year: 2011

In the present study the reproductive biology of Tonna galea (Linnaeus, 1758) was studied for the first time. In mid-September 2006 one individual was found laying a pale pink egg rosette of 39.5 cm length. Number of embryos, stages of development, shape and dimensions were studied in relation to time and measured on microphotographs of randomly sampled capsules. Each oval or spherical shaped capsule of 3.61 mm total length contained 101 developing embryos. The embryo diameter ranged from 297.5 μm of the unsegmented egg to 489 μm of the free veliger. At 21°C eclosion occurred 34 days after capsule deposition, at a free-swimming veliger stage. The duration of each developmental stage, from one cell to veliger, is reported. Results are discussed in relation to possible culture and use for ecological purposes.


News Article | December 7, 2015
Site: phys.org

For the first time in fish, the team scientifically demonstrated that exposure to stress resulted in 'emotional fever' – where fish temporarily increased their body temperatures by up to four degrees Celsius by moving through a thermal gradient. Dr Sonia Rey, Research Fellow at the University of Stirling's Institute of Aquaculture said: "Our study reopens the discussion upon sentience in fish, which is fundamental to our knowledge of the species and their welfare. This will have a bearing on the development of future regulations and mitigation measures around fish. "With fish brains lacking a cerebral cortex, unlike mammals, birds and reptiles, it has been claimed to date that they have no consciousness. This research removes one of the key arguments underpinning that claim." The research, which focussed on zebrafish, also involved the Universitat Autònoma de Barcelona and the University of Bristol. It features in the journal Proceedings of the Royal Society B. Dr Rey said: "Fish cannot internally regulate their own body temperature. Rather, it equates to the temperature of the environment they are in, and so fish travel between different waters to attain their optimal temperature. "In our study we allowed the fish to choose their own temperature by providing them with a thermal gradient in which they could freely move between interconnected chambers holding water at varying degrees Celsius. "Groups of fish that had been gently submerged in a net for a short period chose to travel, when they were released back into the same temperature chamber, to warmer waters, where they then stayed for several hours. "This 'emotional fever' was the effect of their short confinement. Further studies are now needed to explore the underlying mechanisms of this stress-induced hyperthermia, and to test it against different stressors." Dr Simon MacKenzie, Reader in Marine Biotechnology at the Institute of Aquaculture, said: "Our study has significant impact upon our understanding of how fish use thermal choice to optimise their response to stress. This game changing observation will have far reaching implications in how we approach research in fish and how we consider their welfare." Explore further: Fish go deep to beat the heat


News Article | November 15, 2016
Site: www.techtimes.com

The way fish react to stress is strongly connected to their personality, and remains unchanged no matter the situation, according to new research done by scientists from the University of Stirling. The research was conducted by aquaculture specialists who analyzed the way juvenile and mature Senegalese sole fish faced stressful challenges. According to the team, the results will help farmers in the process of screening fish more easily from a young age in order for the animals to be encouraged to reproduce in captivity. This way, the aquaculture production will be improved, addressing the decrease in the species' population. The research suggests very similar behaviors within various situations in fish with the same personality. As it turns out, their behavior is consistent regardless of the restraint and confinement they are faced with or the type of environment they find themselves in. This means that fish that have a particular trait - being proactive and curious, for instance - display the same exploratory behavior across different personality tests. The behavioral activity in the Senegalese sole fish can be grouped in similar patterns depending on the animals' natural wiring. Furthermore, according to the research, the behaviors remain consistent when fish of different age groups are compared. Research fellow Sonia Rey Planellas of the Institute of Aquaculture explained that despite the fact that the species is farmed across the entire European continent, the males find it difficult to reproduce. This incapacity has slowly and steadily affected the populations of Senegalese sole fish. However, the findings of the study suggest that fish who are more outgoing will keep their tendency to reproduce, whether in captivity or not. This means identifying which fish can better cope with stress early on can lead to better species farming and therefore a larger Senegalese sole population. For the study published in Royal Society Open Science, the researchers conducted three separate tests simulating life in captivity on around 120 fish. The fish underwent grouping tests as well as individual behavioral tests, after which their stress responses were observed by measuring the amount of lactate, cortisol and glucose in their blood samples. The researchers said that their Operational Behavioral Screening Tests do not require any special equipment and may also be used in studying the behavior of other fish that fail to reproduce normally. "We hope this can be replicated by fish farmers, large and small, to help establish selection-based breeding programs and easily identify fish that deal best with stress and will be able to reproduce more successfully in a variety of environments," Planellas said. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.


News Article | November 10, 2016
Site: www.sciencedaily.com

Aquaculture experts from the University of Stirling and the Institute for Food and Agricultural Research and Technology (IRTA) in Catalonia, have found the way fish, Senegalese sole, cope with stress is determined by their personality and remains consistent regardless of the situation they are in. Experts hope the first study to test stress copying styles in mature Senegalese sole, will help farmers screen fish from a young age to help the species reproduce in captivity and improve aquaculture production. Scientists found when faced with confinement, restraint or a new environment, younger fish known as juveniles and older fish known as breeders, had similar behavioural patterns and levels of activity, showing consistent responses in animals of different ages. There was also a correlation between how individuals with the same sort of personality acted across the various tests, suggesting that those who are reactive and fearful or proactive and curious, maintain this behaviour. Dr Sonia Rey Planellas, Research Fellow in the Institute of Aquaculture, said: "Senegalese sole is a very valuable fish farmed across Europe, however first generation males' failure to reproduce is still a problem affecting production of the species. Animals who are proactive and try to explore are likely to reproduce in captivity so it's important these fish can be identified at a young age. "The three tests we used to simulate life in captivity was easy to apply and required no special equipment. We hope this can be replicated by fish farmers, large and small, to help establish selection-based breeding programmes and easily identify fish that deal best with stress and will be able to reproduce more successfully in a variety of environments. These Operational Behavioural Screening tests (OBST) can also be used for other species of interest facing similar problems on domestication and production." The research, which also involved researchers from the Spanish Institute of Oceanography, is published in Royal Society Open Science. Around 120 Senegalese sole take part in five individual behavioural tests and two grouping tests. Cortisol, glucose and lactate in the blood was measured at the end of the tests to measure the stress response.


News Article | November 10, 2016
Site: www.eurekalert.org

Aquaculture experts from the University of Stirling and the Institute for Food and Agricultural Research and Technology (IRTA) in Catalonia, have found the way fish, specifically Senegalese sole, cope with stress is determined by their personality and remains consistent regardless of the situation they are in. Experts hope the first study to test stress copying styles in mature Senegalese sole, will help farmers screen fish from a young age to help the species reproduce in captivity and improve aquaculture production. Scientists found when faced with confinement, restraint or a new environment, younger fish known as juveniles and older fish known as breeders, had similar behavioural patterns and levels of activity, showing consistent responses in animals of different ages. There was also a correlation between how individuals with the same sort of personality acted across the various tests, suggesting that those who are reactive and fearful or proactive and curious, maintain this behaviour. Dr Sonia Rey Planellas, Research Fellow in the Institute of Aquaculture, said: "Senegalese sole is a very valuable fish farmed across Europe, however first generation males' failure to reproduce is still a problem affecting production of the species. Animals who are proactive and try to explore are likely to reproduce in captivity so it's important these fish can be identified at a young age. "The three tests we used to simulate life in captivity was easy to apply and required no special equipment. We hope this can be replicated by fish farmers, large and small, to help establish selection-based breeding programmes and easily identify fish that deal best with stress and will be able to reproduce more successfully in a variety of environments. These Operational Behavioural Screening tests (OBST) can also be used for other species of interest facing similar problems on domestication and production." The research, which also involved researchers from the Spanish Institute of Oceanography, is published in Royal Society Open Science. Around 120 Senegalese sole take part in five individual behavioural tests and two grouping tests. Cortisol, glucose and lactate in the blood was measured at the end of the tests to measure the stress response. The study formed part of Zohar Ibarra-Zatarain's PhD thesis who is now working in the Nayarit Centre of Technology Innovation and Transfer (CENIT2) in Tepic, México.

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