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Enumeration	Reference	Cover	Find
1.	Both, Adrianus, 1985-, et al. (author) Physical and biochemical properties of effluent leaving an onshore Atlantic cod (Gadus morhua, Linnaeus 1758; Gadiformes: Gadidae) aquaculture facility and potential use in integrated multi-trophic aquaculture 2013 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 44:12, s. 1940-1951 Journal article (peer-reviewed)abstract The physical and biochemical properties of Atlantic cod (Gadus morhua) wastes were analysed, and the waste remediation potential of blue mussels (Mytilus edulis) was assessed. Waste generated daily by Atlantic cod represented 24.9% of the cod feed added to the system. Particle distributions determined using a Coulter Multisizer and image analysis revealed that the majority of the particles in terms of numbers occupy the smaller size ranges; however, larger particles occupy a larger proportion of the volume. Effluent was composed of particles <70 μm (36%), 70-500 μm (31%) and particles >500 μm (33%) by weight. The amount of dissolved carbon and nitrogen associated with the effluent represented 3.1% and 3.7%, respectively, of the total feed added to the system daily. Particles <70 μm had significantly less organic matter, lipids and fatty acids and were expected to be ingested more by mussels than larger particles. The major lipid classes present in effluent were free fatty acids, triacylglycerols, phospholipids, acetone mobile polar lipids and sterol. Cod effluent contained two essential fatty acids DHA and EPA, a diatom marker (16:1ω7), as well as two zooplankton markers 22:1ω11 and 20:1ω9, which accumulated in mussels and may serve as markers for aquaculture wastes. Although only 36% of the effluent was of a size suitable for mussel ingestion, this size fraction has the greatest potential to spread to surrounding areas. These particulates may be useful as an alternate food source when natural seston is low.
2.	Bergman, Eva, 1959-, et al. (author) Raising brown trout (Salmo trutta) with less food - effects on smolt development and fin damage 2013 In: Aquaculture Research. - : Wiley-Blackwell. - 1355-557X .- 1365-2109. ; 44, s. 1002-1006 Journal article (peer-reviewed)
3.	Einarsdottir, Ingibjörg, 1951, et al. (author) Effects of rearing stress on Atlantic salmon (Salmo salar L.) antibody response to a non-pathogenic antigen. 2000 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 31:12, s. 932-930 Journal article (peer-reviewed)abstract This study was carried out to test the effects of acute stress on the primary and the secondary antibody responses in Atlantic salmon (Salmo salar L.). Fish received a primary immunization with sheep red blood cells (SRBC) and received a second immunization 11 weeks later. At priming, a group of fish was stressed by water level reduction for 30 min (moderate stress), and another group was stressed severely by applying the stressor twice, with an interval of 6 h, 3 days in a row (severe stress). At the time of the booster, another two groups of previously unstressed, primed fish were treated likewise. Unstressed fish mounted a primary antibody response to SRBC and a secondary response, which was improved compared with the primary response., The primary antibody response against SRBC was impaired by severe, but not moderate, acute stress at priming, whereas the secondary antibody response was unaffected. Both moderate and severe stress at the time of the booster was immunosuppressive in fish that had been primed under non-stress conditions. It is concluded that cortisol release as a result of stress exposure is most immunosuppressive at the time of the second immunization.
4.	Kiessling, Anders (author) Anaesthesia of Atlantic halibut (Hippoglossus hippoglossus) - Effect of pre-anaesthetic sedation, and importance of body weight and water temperature 2011 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 42, s. 1235-1245 Journal article (peer-reviewed)abstract The efficacy of the anaesthetic agents benzocaine, metacaine (MS-222), metomidate, 2-phenoxyethanol, quinaldine and isoeugenol was studied in Atlantic halibut (Hippoglossus hippoglossus). Fish with an average body weight of 33 g were anaesthetized at 8 degrees C and fish with an average body weight of 1243 g were anaesthetized at 8 and 15 degrees C. Agents were tested individually and as combination anaesthesia comprising pre-anaesthetic sedation, followed by anaesthesia. Induction and recovery times varied in relation to the body weight and water temperature. Large fish had longer induction times and shorter recovery times, and displayed reduced responsiveness to handling compared with small fish. A higher temperature resulted in shorter induction times, longer recovery times and increased responsiveness to handling. Lower dosages were used for all agents in combination anaesthesia. In small fish, this had no effect on the induction times but resulted in shorter recovery times and reduced responsiveness to handling. In large fish, combination anaesthesia resulted in shorter induction times whereas no uniform trend in recovery times and no differences in responsiveness to handling were observed. Neither individual agents nor combinations blocked all reflex reactions to external stimulation in all fish of any treatment group. MS-222 and benzocaine, used separately or in combination anaesthesia, were the most effective agents in reducing reflex reactions.
5.	Lindberg, Jan Erik, et al. (author) Evaluation of potential feed sources, and technical and economic considerations of small-scale commercial striped catfish (Pangasius hypothalamus) pond farming systems in the Mekong Delta of Vietnam 2013 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 44, s. 427-438 Journal article (peer-reviewed)abstract A technical and socio-economic survey was conducted in Dong Thap, Can Tho and An Giang, provinces of Vietnam in 2009. The results showed that most of the small scale farmers of striped catfish (Pangasius hypothalamus) carry out fish pond culture, developed and operated by self-learned experience and from neighbours knowledge. The mean pond depth varied from 3.5 to 4.0m, ranging from 2 to 6m. Most of the fish farms have extremely high stocking density, with an average of about 40fishm2, in some cases up to 70fishperm2. The average yields and net income of small-scales pond farming is about 2127kg perm2crop1 and US$ 0.1840.329 kg1crop1 respectively. These figures are not significantly different compared with large-scale pond farming. About 75%, 86% and 80% of fish farmers in Dong Thap, Can Tho and An Giang province, respectively, received positive net returns. Farm-made feed is still playing an important role because of higher net profit compared with commercial pellet feeds. Rice bran and trash fish are the main feed ingredients for farm-made feed formulations. Striped catfish farmers are now actively searching for locally produced plant protein sources as alternatives to marine trash fish or fish meal.
6.	Mraz, Jan, et al. (author) Sesamin as a potential modulator of fatty acid composition in common carp (Cyprinus carpio) 2010 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 41, s. e851-e861 Journal article (peer-reviewed)abstract Sesamin enhances the DHA content of tissue lipids in salmonid fish. We have examined whether this effect also occurs in common carp (Cyprinus carpio). Two-year-old common carps were fed a diet containing 5.8 g sesamin kg-1 feed for 69 days. No significant differences were found in the fish weight, specific growth rate, food conversion ratio and lipid content in white muscle. The experimental diet with sesamin increased the percentage of 18:3 n-3 and decreased 18:4 n-3, 22:5 n-3, 22:6 n-3 as well as the desaturation index reflecting the ratio of n-3 long-chain polyunsaturated fatty acids/18:3 n-3 in the triacylglycerol fraction. Sesamin increased the total cytochrome P450 content in hepatopancreatic microsomes as well as 7-ethoxyresorufin O-deethylase (EROD) activity. However, a detailed microarray analysis using 26K gene probes failed to establish any significant pattern of transcriptional response, including lipid biosynthetic genes. Together, these results indicate that under conditions of our study, sesamin was ineffective in the common carp as a means of achieving the changes in the tissue lipid composition as were seen in salmonids.
7.	Sverdrup, Gisle K., et al. (author) Territorial and agonistic interactions between farmed and wild cod (Gadus morhua) 2011 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 42:10, s. 1539-1548 Journal article (peer-reviewed)abstract Studies of contest competition between wild and farmed fish have mostly focused on fish with strongly territorial behaviour. Little is known about species with more plastic social behaviour, such as Atlantic cod (Gadus morhua L.), a species that can either aggressively defend territories or shoal. There is also concern that cod that escape from farms will compete with wild populations. We examined dyadic contest competition between wild and farmed juvenile cod using an intruder-resident experimental set-up in the laboratory. No prior residency advantage was observed, but the differences between farmed and wild cod were clear. Farmed cod were more submissive than wild cod and fled earlier during contests, which suggests that wild fish often out-compete farmed intruders. Both fish types initiated aggression earlier against fish of the same background. A multivariate analysis of 11 different behavioural traits indicated that a group of 59% of farmed fish were behaviourally very similar to the 55% most submissive wild fish. These results suggest that wild juvenile cod may be quite robust towards competition for food and shelter from juvenile farmed cod, but further research is needed to verify this pattern.
8.	Bergström, Per, 1980, et al. (author) Testing the potential for improving quality of sediments impacted by mussel farms using bioturbating polychaete worms 2017 In: Aquaculture Research. - : Hindawi Limited. - 1365-2109 .- 1355-557X. ; 48:1, s. 161-176 Journal article (peer-reviewed)abstract Biodeposits from farmed mussels severely influence the biogeochemistry of sediments by increasing the levels of organic matter (OM). Mitigation of such negative impacts is important for the development of sustainable aquaculture operations. As a step towards developing methods for remediation of coastal sediments affected by mussel farming, the effects of the polychaete, Hediste diversicolor was evaluated experimentally. In a series of field- and laboratory experiments we tested hypotheses about the effects of polychaetes on sediment oxygen consumption, nutrient fluxes and sulphide pools under different polychaete densities and sedimentation regimes. The experimental results support the idea that polychaetes can mitigate negative effects on the benthic environment beneath mussel farms. H.diversicolor oxidized the sediment and generally enhanced the oxygen consumption, and thus the decomposition of OM. The accumulation of pore water sulphides were reduced and fluxes of nutrients across the sediment-water interface increased. Additional calculations suggest that the effects of polychaetes were mainly indirect and driven by increased microbial activity due to the borrowing activity of the polychaetes. Trends of increasing decomposition with increasing polychaete density suggest that the decomposition could be further enhanced by higher densities. Overall, we concluded that H.diversicolor is a potentially strong candidate for remediation of mussel farm sediments. The results show that sediments inhabited by H.diversicolor have high assimilative capacity of OM and oxygen conditions are significantly improved following the addition of polychaetes at naturally occurring densities. However, technological developments are needed in order to allow the approach to be used in practice.
9.	Bowman, Jennifer, et al. (author) Evaluation of the reliability of indicators of consciousness during CO2 stunning of rainbow trout and the effects of temperature 2020 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 51, s. 5194-5202 Journal article (peer-reviewed)abstract A two-part experiment was conducted to determine whether visual indicators of consciousness such as equilibrium, eye-roll reflex and ventilation are reliable for evaluating whether CO2 stunning of rainbow trout (Oncorhynchus mykiss) is humane. In part 1, the time taken until the loss of visual indicators in rainbow trout during CO2 stunning was monitored under field conditions at 14, 8 and 2 degrees C. Here, we clearly demonstrate that it takes longer for visual indicators to disappear as temperature decreases, with significant differences in the time taken until the loss of equilibrium between 2 and 14 degrees C, and significant differences between all temperatures in the time taken until the loss of eye-roll reflex and ventilation. In part 2, rainbow trout were equipped with external non-invasive electrodes for recording EEG prior to, and following, CO2 stunning to assess the presence or absence of visually evoked responses (VERs), which are indicative of brain function and sensibility. The resulting EEG recordings during CO2 stunning at 10 degrees C demonstrated a poor relationship between visual indicators of consciousness and loss of sensibility, as VERs were present up to 3.5 min after ventilation was lost and up to 6.5 min after the fish lost equilibrium. Collectively, these results show that cold-water temperatures prolong the time taken until loss of consciousness and that visual indicators are insufficient for determining when sensibility is lost in rainbow trout during CO2 stunning.
10.	Bowman, Jennifer, et al. (author) Non-invasive recording of brain function in rainbow trout: Evaluations of the effects of MS-222 anaesthesia induction 2019 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 50:11, s. 3420-3428 Journal article (peer-reviewed)abstract Effective methods of producing instantaneous and irreversible unconsciousness at the time of slaughter are crucial for ensuring animal welfare in commercial aquaculture. However, the traditional method of visually evaluating unconsciousness has been shown to be insufficient and may lead to misjudgements of stunning efficiency. In this study, we developed a non-invasive technique that measures brain activity in fish as an alternative to traditional invasive, brain implants and used it to determine when a change in consciousness occurs in trout during anaesthesia induction. Nine rainbow trout (Oncorhynchus mykiss) were equipped with a custom designed silicone cup fitted with electrodes and submerged in 10 degrees C water with dissolved MS-222. During anaesthesia, the state of consciousness was assessed by recordings of electroencephalogram (EEG). The EEG recordings were analysed both by visually evoked responses from light stimulation (VERs) and from changes in signal amplitude, median frequency and relative signal power. According to the loss of VERs and decrease in signal amplitude, trout transitioned to surgical depth of anaesthesia within 5 min. Our results show that consciousness, or loss of, can be determined using a non-invasive system to record EEG in fish.
11.	Guo, H. Y., et al. (author) Effects of different feeding regimes on juvenile black rockfish (Sebastes schlegilii) survival, growth, digestive enzyme activity, body composition and feeding costs 2020 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 51:10, s. 4103-4112 Journal article (peer-reviewed)abstract The objective of this study was to establish a proper feeding regime for juvenile black rockfish (Sebastes schlegilii) intended for stock enhancement. We used a combined experimental design to assess the effects of different feeding rates (1%, 3% and 5% body weight per day (BW/day)) and feeding frequencies (apparent satiety or restricted feeding 1 to 3 times daily) on survival, growth, digestive enzyme activity, body composition and feeding costs over 50 days, from newly weaned (initial average weight 1.5 +/- 0.2 g) to release size. The results showed that feeding rate significantly affected fish growth, feed utilization and body composition. The highest feed conversion ratio was at 3% BW/day. Increased feeding rates resulted in enhanced growth and higher body lipid content, but this was also accompanied by decreased contents of moisture, protein and ash. With feeding to apparent satiety, increased feeding frequency resulted in higher growth performance and enhanced intestinal lipase activity but decreased gastric protease activity. There were no growth improvements or effects on digestive enzyme activity and body composition with increasing feeding frequency (from one to three times daily) under a fixed-quantify feeding (3% BW/day). Feed costs increased with increasing feeding rates or apparent satiety feeding frequencies and were associated with shorter growth times to reach a suitable size for release. Our study suggests that a feeding rate of 3% BW/day is the best feeding regime for proper growth and reduced feed costs in juvenile black rockfish before releasing for stock enhancement.
12.	Hinchcliffe, James, 1992, et al. (author) Comparative survival and growth performance of European lobster Homarus gammarus post-larva reared on novel feeds 2020 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 51:1, s. 102-113 Journal article (peer-reviewed)abstract One approach to ongrow juvenile European lobster, Homarus gammarus, is to utilize land based rearing systems, incorporating automated feeding, individual culture and provision of stable pelleted feeds, preferably using sustainable ingredients. We initiated three feeding experiments to investigate the general suitability of ingredients produced from seafood by-products as novel feeds for H. gammarus, in terms of promoting survival, development and growth of post-larval lobsters from post-larvae (PL) stage IV to the first juvenile stage (stage V). The first experiment was designed to screen an array of candidate, locally produced, novel protein sources on growth performance parameters. This initial experiment revealed that PL reared on a raw (i.e. wet, unprocessed shrimp) feed used as a reference showed superior performance to those reared on experimental feeds containing fishmeal, herring protein isolate or mussel meal; however, a novel type of shrimp meal, produced by flocculation from waste water, promoted the best PL performance of any experimental feed. A second experiment was designed to test the effect of drying method and to optimize the form of a wet shrimp reference feed used by lobster hatcheries. This showed that the performance of PL reared on experimental freeze-dried shrimp feed was not significantly different to those reared on the wet, unprocessed shrimp used as a reference feed. However, lobsters offered experimental oven-dried shrimp feed (with or without an immune supplement) resulted in significantly lower survival or growth performance. A third and final experiment was designed in an attempt to improve a candidate herring-based protein source, by supplementing with nutrients found in shrimp. However, the results showed that PL reared on the wet reference shrimp feed still showed superior growth and survival than those reared on a herring feed alone, or supplemented with additives found in shrimp meal (either glucosamine, astaxanthin or both supplements combined). The high survival and growth, low incidence of moulting problems and high availability of waste shrimp material, suggest that non-heat-treated shrimp products are a promising feed ingredient for post-larval European lobsters.
13.	Jeuthe, Henrik, et al. (author) Effects of variable egg incubation temperatures on the embryonic development in Arctic charr Salvelinus alpinus 2016 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 47, s. 3753-3764 Journal article (peer-reviewed)abstract An evaluation of different thermal regimes during incubation of Arctic charr Salvelinus alpinus L. egg was conducted with regard to embryo survival and development. The study consisted of two major parts: In experiment A, a range of commonly used thermal regimes, constant and variable ranging from 2.7 degrees C to 7 degrees C, were tested for differences in embryo survival and developmental status of newly hatched alevins. Experiment B assessed the timing of a shift from autumn (6 degrees C) to winter temperature (2.5 degrees C) and its effect on embryo survival and the occurrence of spinal deformities in newly hatched alevins. In general, incubations that were initiated at temperatures below 3 degrees C resulted in significantly higher mortality rates and spinal deformity frequencies than other treatments. Hence, Arctic charr eggs require an initial warmer period for unimpaired embryonic development. A general negative correlation was found between the duration of this warmer period (6 degrees C) and both mortality rates and frequency of spinal deformities. The total absence of the 6 degrees C period had the most detrimental effect, with deformity frequencies at least four times higher than all treatments with an initial warmer period. The upper incubation temperature threshold was not reached in the study. The highest temperature tested (7 degrees C) did not result in excess mortality or increased deformity frequency. Higher incubation temperature resulted in less developed alevins at hatching, i.e. alevins were smaller with more yolk remaining. However, measurements on alevins from incubations at variable temperatures revealed different temperature effects on growth and yolk consumption during different parts of embryonic development.
14.	Li, Jinghua, et al. (author) Effects of dissolved oxygen on the growth performance, haematological parameters, antioxidant responses and apoptosis of juvenile GIFT (Oreochromis niloticus) 2020 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 51:8, s. 3079-3090 Journal article (peer-reviewed)abstract This study investigated the effects of different dissolved oxygen (DO) levels on the growth performance, antioxidant response and apoptosis of juvenile GIFT (genetically improved farmed tilapia, Oreochromis niloticus). GIFT were fed with five DO levels (1, 2, 3, 4 and 5 mg/L) for 60 days, and the results showed that the final body weight, weight gain rate, specific growth rate and crude protein and crude lipid contents of the fish muscle increased at 5 mg/L DO. The activities of the antioxidant and digestive enzymes were significantly up-regulated with increasing DO levels. However, the haemoglobin content, number of red blood cells, malondialdehyde content, transaminase activities, glucose content and lactic acid levels decreased at higher DO levels. Furthermore, the cardiomyocyte apoptotic index was significantly decreased with increasing DO levels. Our results show that 5 mg/L DO improved growth performance, promoted antioxidant enzyme activities and reduced liver damage in GIFT.
15.	Moksnes, Per-Olav, 1965, et al. (author) Stepwise function of natural growth for Scylla serrata in East Africa : a valuable tool for assessing growth of mud crabs in aquaculture 2015 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 46:12, s. 2938-2953 Journal article (peer-reviewed)abstract Predicting growth is critical in aquaculture, but models of growth are largely missing for mud crab species. Here, we present the first model of natural growth in juvenile and adult mud crabs Scylla serrata from East Africa using a stepwise growth function based on data on intermoult periods and growth at moult from field mark-recapture, pond and laboratory studies. The results showed a sigmoid growth pattern in carapace width and suggest that S.serrata in East Africa will reach 300g and sexual maturity similar to 9.9months after settlement, and a commercial size of 500g after 12.4months. Analyses of the literature identified several issues with the common praxis to compare standard growth measures between aquaculture studies with different initial size or growing periods. Using the new growth function to estimate the proportional difference between modelled and obtained growth as an alternative method, we show that growth rates of S.serrata cultured in cage systems, which are dominant in East Africa, was <40% of the estimated natural growth and growth obtained in pond systems. The analysis also indicated that growth rates of S.serrata in Southeast Asia was over 50% higher compared with similar culture systems in East Africa, and that different species of mud crabs had large differences in growth rates. This study shows that growth in the present mud crab aquaculture systems in East Africa is below their expected potential. Further work is needed to identify the factors behind this observation.
16.	Powell, Adam, 1981, et al. (author) Comparative survival and growth performance of European lobster larvae, Homarus gammarus, reared on dry feed and conspecifics 2017 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 48:10, s. 5300-5310 Journal article (peer-reviewed)abstract A bottleneck of crustacean larval culture concerns nutrition and associated cannibalism in communal rearing systems, which impact on larval survival, development and growth. For early stage European lobster, Homarus gammarus larvae, feeding ecology and body composition is largely unknown. We initiated four progressive feeding experiments (novel feed types, feeding regime and feed size) on growth and survival, to inform and update husbandry protocols. Performance of larvae offered a dry commercial feed was not significantly different compared to a conventional wet plankton feed of the same ration and size grade (both within 600-1000 µm). Further experiments found that the same ration of dry feed offered 6 times daily improved development and growth, over the conventional regime of 3 times daily. Small grade dry feed (particles 250-360 µm) improved larval performance compared to a larger feed (360-650 µm). Larvae were also fed different proportions of dry feed and/or conspecifics in both communal and individual rearing systems (the latter preventing cannibalism via segregation). Individually reared larvae, fed only dead conspecifics, displayed the greatest survival (80%) to post larvae. This underlines the impact of cannibalism on survival and nutrition in H. gammarus larviculture. A final experiment analysed H. gammarus zoea 1 composition, identifying deficiencies in ash and carbohydrate in lobster feeds. This suggests a need for a species specific, formulated dry feed for H. gamarus larviculture. Our research represents the first investigation of H. gammarus larval composition and dietary requirements, and highlights decreased growth potential associated with providing nutrition solely from generic commercial feed.
17.	Sampels, Sabine, et al. (author) Egg oxidation status, antioxidant enzyme activities, lipid classes, fatty acid composition profile and embryo survival rates during in vitro oocyte ageing in tench Tinca tinca (Linnaeus, 1758) 2018 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 49, s. 2305-2316 Journal article (peer-reviewed)abstract The effect of invitro storage of oocytes on embryos survival rate, egg oxidation status, antioxidant enzyme activities, lipid classes and fatty acid composition profile was investigated in common tench Tinca tinca. In order to identify the role of oxidative stress in the progress of oocyte ageing the levels of thiobarbituric acid reactive substances (TBARS) and carbonyls as indicators of lipid and protein oxidation were measured and the activity of antioxidant enzymes were examined. Stripped ova from six females were stored in cell culture plates at 20 degrees C for up to 10 hr post-stripping (HPS). The stored ova were fertilized and the embryo survival rates were assessed. The results indicated that tench eggs could be successfully stored invitro for 4 hr after stripping at 20 degrees C. Superoxide dismutase enzyme activity increased at 6 HPS, whereas glutathione peroxidase and glutathione reductase activities decreased in oocytes during in vitro storage (p < .05) at 4 and 8 HPSs, respectively. The level of malondialdehyde did not show any significant changes during the progress of oocyte ageing. Carbonyls increased up to 2 HPS and thereafter decreased significantly. However, ova ageing did not affect the main lipid class composition and the fatty acid composition of the eggs. Lower quality eggs exhibited lower levels of cholesterol but higher levels of triacylglycerol.
18.	Sampels, Sabine (author) mRNA abundance changes during invitro oocyte ageing in African catfish Clarias gariepinus (Burchell, 1822) 2018 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 49, s. 1037-1045 Journal article (peer-reviewed)abstract Delayed fertilization following ovulation leads to the oocyte ageing which has been identified as the most important factor affecting egg quality after ovulation. Very little is known about the molecular changes associated with the progress of oocyte ageing. The present study monitored the egg viability rates during post-stripping oocyte ageing in African catfish Clarias gariepinus. In addition the mRNA abundance of selected genes were studied during the progress of oocyte ageing by real time quantitative PCR. To study how maternal transcripts influence egg quality, expression levels were correlated with egg hatching rates. The highest embryo survival and hatching rates (88% and 81%, respectively) were obtained from eggs that were fertilized immediately after stripping. Complete loss of egg viability occurred at 16 and 24 hr Post Stripping (HPS) when eggs were stored at 25 degrees C and 4 degrees C respectively. Under both storage temperatures, the embryo mortality and larval malformation rates increased significantly over time and were the highest in the most aged oocytes. Genes indicating an upward trend in expression during ova ageing were determined to be related to oxidative injury and the stress response (hsp70), mitochondrial function (calmodulin), apoptosis (cathepsin D) and germ line speciation (vasa and sox9a). The results suggest that oxidative stress and mitochondrial dysfunction might be associated with post-stripping ova ageing and the consequent induction of egg quality defects. The examined genes may be considered as candidate markers of egg quality associated with oocyte ageing in African catfish.
19.	Sampels, Sabine (author) Relationship between lipid and protein oxidation in fish 2019 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 50, s. 1393-1403 Research review (peer-reviewed)abstract Reactive oxygen species (ROS) are generated in all aerobic organisms. Free radicals are highly reactive ROS that cause damage to biological materials. Fish is rich in polyunsaturated fatty acids, and hence, very prone to lipid peroxidation. Both lipid and protein oxidations are important for quality loss during storage of fish, with high impact on taste and texture. Also, there are interactions between protein and secondary lipid oxidation products (aldehydes) that occur in foods because the oxidation products from one reaction can further react with both lipids and proteins respectively. This review focuses on the mechanisms and pathways of the lipid and protein oxidation and their possible relationship. Additionally, the target amino acids and final impacts of this relationship were considered. We propose that the products of lipid oxidation promote protein oxidation in fish rather than the other way around specially, during frozen storage, while during postmortem changes protein oxidation dominates. Finally, it seems that, secondary products of lipid oxidation might have more impact on the functionality of proteins from both Michael addition and Schiff base reaction rather than lipid hydroperoxides and lipid radical transfer.
20.	Zajic, Tomas, et al. (author) Evaluation of the effect of dietary sesamin on white muscle lipid composition of common carp (Cyprinus carpio L.) juveniles 2016 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X .- 1365-2109. ; 47, s. 3826-3836 Journal article (peer-reviewed)abstract This study was focused on the clarification of the effect of dietary sesamin on fatty acids and the composition of different lipid fractions [phospholipids (PLs), cholesterol and triacylglycerols] in the white muscle of common carp (Cyprinus carpio L.) juveniles. Two different basic diets with defatted fishmeal as a protein source and either only linseed oil or a mixture of linseed and sunflower oil as a lipid source designed to have two different n-3/n-6 ratios (1.21 - CL group; 0.32 - CM group) were produced. Each diet was then used with or without added sesamin (0.58 g 100g(-1)). One hundred and forty-four individuals were fed in triplicated groups for 63 days until their weight had doubled. No influence of dietary sesamin on growth, mortality or on the white muscle lipid content of the fish was found. Added sesamin significantly decreased the content of PLs and increased the cholesterol content in the CM group. No effect was found in the total lipid fatty acid composition but there was found a significantly lower content of saturated fatty acids and 20: 5n-3 in PLs and of 22: 6n-3 in triacylglycerols in the sesamin supplemented CL group. These and other differences show either a tendency of lower long chain n-3 fatty acids biosynthesis or their higher use in beta-oxidation in sesamin-supplemented groups. We conclude that sesamin in this experiment had no substantial positive impact on the lipid metabolism of juvenile carp.
21.	Sisk-Reynés, Júlia, et al. (author) New constraints on light axion-like particles using Chandra transmission grating spectroscopy of the powerful cluster-hosted quasar H1821+643 2022 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 510:1, s. 1264-1277 Journal article (peer-reviewed)abstract Axion-like particles (ALPs) are predicted by several Beyond the Standard Model theories, in particular, string theory. In the presence of an external magnetic field perpendicular to the direction of propagation, ALPs can couple to photons. Therefore, if an X-ray source is viewed through a magnetized plasma, such as a luminous quasar in a galaxy cluster, we may expect spectral distortions that are well described by photon–ALP oscillations. We present a 571 ks combined high- and low-energy transmission grating Chandra observation of the powerful radio-quiet quasar H1821+643, hosted by a cool-core cluster at redshift 0.3. The spectrum is well described by a double power-law continuum and broad+narrow iron line emission typical of type-1 active galactic nuclei (AGNs), with remaining spectral features <2.5 per cent<2.5 per cent⁠. Using a cell-based approach to describe the turbulent cluster magnetic field, we compare our spectrum with photon–ALP mixing curves for 500 field realizations, assuming that the thermal-to-magnetic pressure ratio β remains constant up to the virial radius. At 99.7 per cent99.7 per cent credibility and taking β = 100, we exclude all couplings gaγ > 6.3 × 10−13 GeV−1 for most ALP masses <10−12 eV. Our results are moderately more sensitive to constraining ALPs than the best previous result from Chandra observations of the Perseus cluster, albeit with a less constrained field model. We reflect on the promising future of ALP studies with bright AGNs embedded in rich clusters, especially with the upcoming Athena mission.
22.	Ljunggren, L, et al. (author) Weaning of juvenile pikeperch (Stizostedion lucioperca (L.)) and perch (Perca fluviatilis (L.)) to formulated feed. 2003 In: Aquaculture Research. - 1355-557X. ; 34:4, s. 281-287 Journal article (peer-reviewed)abstract Weaning success of pond-cultured pikeperch and wild-caught perch (mean length 51 and 48 mm respectively) was evaluated using different weaning techniques and different formulated feeds. Juveniles that were fed formulated feed grew as well as or better than juveniles that were weaned successively using zooplankton or yolk. Four different formulated feeds (agglomerated marine larvae feed, marine larvae feed, trout feed and a semi-moist feed) were evaluated regarding specific growth rate (SGR), condition factor and a subjective stomach fullness estimate. The agglomerated marine larvae feed gave significantly better weaning performance than the other feeds regarding all parameters (SGR = 7.3% day(-1) and 3.4% day(-1) for pikeperch and perch respectively).
23.	Overli, O, et al. (author) Dominance hierarchies in Arctic charr, Salvelinus alpinus L.: differential cortisol profiles of dominant and subordinate individuals after handling stress 1999 In: AQUACULTURE RESEARCH. - : BLACKWELL SCIENCE LTD. - 1355-557X. ; 30:4, s. 259-264 Journal article (other academic/artistic)abstract We examined the effect of social rank on plasma cortisol dynamics after handling stress in juvenile Arctic charr, Salvelinus alpinus L., reared in groups of 200 individuals in 1.5 m(3) circular tanks (rearing density 0.022 kg L-1). Fish obtained by dip-ne
24.	Stigebrandt, Anders, 1942 (author) Carrying capacity: general principles of model construction 2011 In: AQUACULTURE RESEARCH. - 1355-557X. ; 42, s. 41-50 Journal article (peer-reviewed)abstract Carrying capacity is defined as the maximum biomass of a farmed species that can be supported without violating the maximum acceptable impacts to the farmed stock and its environment. Maximum acceptable impacts on the farmed stock and the environment are expressed by standards for water quality in the farm and the surrounding environment. Environmental quality standards are established in a political process. The scientific part of the problem to estimate the carrying capacity is to develop reliable, objective methods or models for estimating the response of both the environment and the farmed stock to farming. Using such models together with field observations from a specified locality and the quality standards in force, the carrying capacity for the locality can be estimated. Models must properly deal with hydrodynamic and biogeochemical and ecological processes in the environment as well as with oxygen consumption and sources and sinks of organic matter and nutrients due to farm activity. In this paper, the basic principles of model construction are discussed and the Norwegian MOM model is used as an example. Current speed data and farm activity data are identified as two generally large sources of uncertainty in estimates of environmental impact and carrying capacity.
25.	Wolska, Julia, et al. (author) Standardized method for the Holmen pellet tester (NHP100) as a tool for evaluating the physical quality of fish feed 2016 In: Aquaculture Research. - : Hindawi Limited. - 1355-557X. ; 47:6, s. 1790-1796 Journal article (peer-reviewed)abstract The fish feed production industry requires reliable methods measuring the physical quality of feed before it is being released to the customer. The Holmen pellet tester (NHP 100) could be adapted for this purpose, but the special characteristics of fish feed require particular care during testing. The aim of the study was to determine the standardized conditions for using the Holmen tester as a tool measuring the durability of fish feed. Screening tests were performed on commercial fish feed samples to assess the effects of temperature, pressure and cleaning the instrument between runs. The operating pressure was found to be the most important factor that can influence the results. The temperature of the operating air can also alter the results; increased temperatures can cause oil to melt and leak from the pellets. Cleaning the instrument between analyses can also affect the results. This study shows that when these factors are maintained at a standardized level, the Holmen pellet tester is a valuable tool for assessing the physical quality of fish feed giving additional information on the quality of feed pellets compared to other durability tests like DORIS.
26.	Aguirre Børsen-Koch, V., et al. (author) The BAyesian STellar algorithm (BASTA) : A fitting tool for stellar studies, asteroseismology, exoplanets, and Galactic archaeology 2022 In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 509:3, s. 4344-4364 Journal article (peer-reviewed)abstract We introduce the public version of the BAyesian STellar Algorithm (BASTA), an open-source code written in Python to determine stellar properties based on a set of astrophysical observables. BASTA has been specifically designed to robustly combine large data sets that include asteroseismology, spectroscopy, photometry, and astrometry. We describe the large number of asteroseismic observations that can be fit by the code and how these can be combined with atmospheric properties (as well as parallaxes and apparent magnitudes), making it the most complete analysis pipeline available for oscillating main-sequence, subgiant, and red giant stars. BASTA relies on a set of pre-built stellar isochrones or a custom-designed library of stellar tracks, which can be further refined using our interpolation method (both along and across stellar tracks or isochrones). We perform recovery tests with simulated data that reveal levels of accuracy at the few percent level for radii, masses, and ages when individual oscillation frequencies are considered, and show that asteroseismic ages with statistical uncertainties below 10 per cent are within reach if our stellar models are reliable representations of stars. BASTAis extensively documented and includes a suite of examples to support easy adoption and further development by new users.
27.	Castro-González, A., et al. (author) The K2-OjOS ProjectNew and revisited planets and candidates in K2 campaigns 5, 16, & 18 2022 In:* Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 509:1, s. 1075-1095 Journal article (peer-reviewed)abstract We present the first results of K2-OjOS, a collaborative project between professional and amateur astronomers primarily aimed to detect, characterize, and validate new extrasolar planets. For this work, 10 amateur astronomers looked for planetary signals by visually inspecting the 20 427 light curves of K2 campaign 18 (C18). They found 42 planet candidates, of which 18 are new detections and 24 had been detected in the overlapping C5 by previous works. We used archival photometric and spectroscopic observations, as well as new high-spatial resolution images in order to carry out a complete analysis of the candidates found, including a homogeneous characterization of the host stars, transit modelling, search for transit timing variations and statistical validation. As a result, we report four new planets (K2-355 b, K2-356 b, K2-357 b, and K2-358 b) and 14 planet candidates. Besides, we refine the transit ephemeris of the previously published planets and candidates by modelling C5, C16 (when available) and C18 photometric data jointly, largely improving the period and mid-transit time precision. Regarding individual systems, we highlight the new planet K2-356 b and candidate EPIC 211537087.02 being near a 2:1 period commensurability, the detection of significant TTVs in the bright star K2-184 (V = 10.35), the location of K2-103 b inside the habitable zone according to optimistic models, the detection of a new single transit in the known system K2-274, and the disposition reassignment of K2-120 b, which we consider as a planet candidate as the origin of the signal cannot be ascertained.
28.	Dominguez, R., et al. (author) Are hierarchically formed embedded star clusters surviving gas expulsion depending on their initial conditions? 2021 In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 508:4, s. 5410-5424 Journal article (peer-reviewed)abstract We investigate the dissolution process of young embedded star clusters with different primordial mass segregation levels using fractal distributions by means of N-body simulations. We combine several star clusters in virial and subvirial global states with Plummer and uniform density profiles to mimic the gas. The star clusters have masses of M-stars = 500 M-circle dot that follow an initial mass function where the stars have maximum distance from the centre of r = 1.5 pc. The clusters are placed in clouds that at the same radius have masses of M-cloud = 2000 M-circle dot, resulting in star formation efficiency of 0.2. We remove the background potential instantaneously at a very early phase, mimicking the most destructive scenario of gas expulsion. The evolution of the fraction of bound stellar mass is followed for a total of 16 Myr for simulations with stellar evolution and without. We compare our results with previous works using equal-mass particles where an analytical physical model was used to estimate the bound mass fraction after gas expulsion. We find that independent of the initial condition, the fraction of bound stellar mass can be well predicted just right after the gas expulsion but tends to be lower at later stages, as these systems evolve due to the stronger two-body interactions resulting from the inclusion of a realistic initial mass function. This discrepancy is independent of the primordial mass segregation level.
29.	Nativi, Lorenzo, et al. (author) Are interactions with neutron star merger winds shaping the jets? 2022 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 509:1, s. 903-913 Journal article (peer-reviewed)abstract Jets can become collimated as they propagate through dense environments and understanding such interactions is crucial for linking physical models of the environments to observations. In this work, we use 3D special-relativistic simulations to study how jets propagate through the environment created around a neutron star merger remnant by neutrino-driven winds. We simulate four jets with two different initial structures, top-hat and Gaussian, and two luminosities. After jet breakout, we study the angular jet structures and the resulting afterglow light curves. We find that the initial angular structures are efficiently washed out during the propagation, despite the small wind mass of only ∼10−3 M. The final structure depends on the jet luminosity as less energetic jets are more strongly collimated, and entrainment of baryons leads to a moderate outflow Lorentz factor (≈40). Although ourjets are not specifically intended to model the outflows of the GW170817 event, we show that they can be used to produce light curves consistent with the afterglow observed in the aftermath of GW170817. Using this procedure, we show how the inferred physical parameters e.g. inclination angle, ambient particle number density, can vary substantially between independent fits of the same dataset, and appear to be sensitive to smaller details of the angular jet shape, indicating that observationally inferred parameters may depend sensitively on the employed jet models.
30.	Puglisi, G., et al. (author) Improved galactic foreground removal for B-mode detection with clustering methods 2022 In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 511:2, s. 2052-2074 Journal article (peer-reviewed)abstract Characterizing the sub-mm Galactic emission has become increasingly critical especially in identifying and removing its polarized contribution from the one emitted by the cosmic microwave background (CMB). In this work, we present a parametric foreground removal performed on to sub-patches identified in the celestial sphere by means of spectral clustering. Our approach takes into account efficiently both the geometrical affinity and the similarity induced by the measurements and the accompanying errors. The optimal partition is then used to parametrically separate the Galactic emission encoding thermal dust and synchrotron from the CMB one applied on two nominal observations of forthcoming experiments from the ground and from the space. Moreover, the clustering is performed on tracers that are different from the data used for component separation, e.g. the spectral index maps of dust and synchrotron. Performing the parametric fit singularly on each of the clustering derived regions results in an overall improvement: both controlling the bias and the uncertainties in the CMB B-mode recovered maps. We finally apply this technique using the map of the number of clouds along the line of sight, Nc, as estimated from H I emission data and perform parametric fitting on to patches derived by clustering on this map. We show that adopting the Nc map as a tracer for the patches related to the thermal dust emission, results in reducing the B-mode residuals post-component separation. The code is made publicly available https://github.com/giuspugl/fgcluster.
31.	Falster, Daniel, et al. (author) The influence of four major plant traits on average height, leaf area cover, net primary productivity, and standing biomass in single-species forests : a theoretical investigation 2011 In: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 99:1, s. 148-164 Journal article (peer-reviewed)abstract Numerous plant traits are known to influence aspects of individual performance, including rates of carbon uptake, tissue turnover, mortality and fecundity. These traits are bound to influence emergent properties of vegetation because quantities such as leaf-area cover, average height, primary productivity and density of standing biomass result from the collective behaviour of individuals. Yet, little is known about the influence of individual traits on these emergent properties, despite the widespread use in current vegetation models of plant functional types, each of which is defined by a constellation of traits. We examine the influence of four key traits (leaf economic strategy, height at maturation, wood density, and seed size) on four emergent vegetation properties (average height of leaf area, leaf-area index, net primary productivity and biomass density). We employ a trait-, size- and patch-structured model of vegetation dynamics that allows scaling up from individual-level growth processes and probabilistic disturbances to landscape-level predictions. A physiological growth model incorporating relevant trade-offs was designed and calibrated based on known empirical patterns. The resulting vegetation model naturally exhibits a range of phenomena commonly observed in vegetation dynamics. We modelled single-species stands, varying each trait over its known empirical range. Seed size had only a small effect on vegetation properties, primarily because our metapopulations were not seed-limited. The remaining traits all had larger effects on vegetation properties, especially on biomass density. Leaf economic strategy influenced minimum light requirement, and thus total leaf area and basal area. Wood density and height at maturation influenced vegetation mainly by modifying individual stem mass. These effects of traits were maintained, and sometimes amplified, across stands differing in productivity and mean disturbance interval. Synthesis: Natural trait variation can cause large differences in emergent properties of vegetation, the magnitudes of which approach those arising through changes to site productivity and disturbance frequency. Our results therefore underscore the need for next-generation vegetation models that incorporate functional traits together with their effects on the patch and size structure of vegetation.
32.	Kos, Janez, et al. (author) The GALAH survey and Gaia DR2 : (non-)existence of five sparse high-latitude open clusters 2018 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 480:4, s. 5242-5259 Journal article (peer-reviewed)abstract Sparse open clusters can be found at high galactic latitudes where loosely populated clusters are more easily detected against the lower stellar background. Because most star formation takes place in the thin disc, the observed population of clusters far from the Galactic plane is hard to explain. We combined spectral parameters from the GALAH survey with the Gaia DR2 catalogue to study the dynamics and chemistry of five old sparse high-latitude clusters in more detail. We find that four of them (NGC 1252, NGC 6994, NGC 7772, NGC 7826) - originally classified in 1888 - are not clusters but are instead chance projections on the sky. Member stars quoted in the literature for these four clusters are unrelated in our multidimensional physical parameter space; the quoted cluster properties in the literature are therefore meaningless. We confirm the existence of visually similar NGC 1901 for which we provide a probabilistic membership analysis. An overdensity in three spatial dimensions proves to be enough to reliably detect sparse clusters, but the whole six-dimensional space must be used to identify members with high confidence, as demonstrated in the case of NGC 1901.

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