Fasting Fish Research Articles

A fast fish swimming protocol that provides similar insights to critical swimming speed.

Performance measures are an important tool to assess the impact of environmental change on animals. In fish, performance is often measured as critical swimming speed (Ucrit), which reflects individual maximal physiological capacities. A drawback of Ucrit is that trials are relatively long (∼30-75 min). Ucrit may therefore not be suitable for several repeated measurements because of the potential for training effects, long recovery periods, and low throughput. Here we test a shorter (∼4-5 min) protocol, "Ucrit fast" (UCfast) in zebrafish (Danio rerio). We show that UCfast and Ucrit have similar, significant repeatabilities within individuals. Unlike Ucrit, repeated UCfast trials did not elicit a training effect. Both UCfast and Ucrit provide the same insights into thermal acclimation, and both provide similar estimates of individual acclimation capacity in doubly acclimated fish. We propose that UCfast is a valid substitute for Ucrit particularly when higher throughput and several repeated measures are necessary.

Targeted screening of multiple anti-inflammatory components from Chrysanthemi indici Flos by ligand fishing with affinity UF-LC/MS.

Chrysanthemi indic Flos (CIF) has been commonly consumed for the treatment of inflammation and related skin diseases. However, the potential bioactive components responsible for its anti-inflammatory and sensitive skin (SS) improvement activities, and the correlated mechanisms of action still remain unknown. In this work, it was firstly found that the CIF extract (CIFE) displayed arrestive free radical scavenging activity on DPPH and ABTS radicals, with no significant difference with positive control Trolox (p > 0.05). Then, compared to the negative group, CIFE markedly decreased the productions of the pro-inflammatory cytokines (IL-1β, IL-6, PEG2, TNF-α, IFN-γ, NO) in LPS induced RAW264.7 cells in a dose-dependent manner (p < 0.01). Besides, CIFE strongly inhibited the COX-2 and hyaluronidase (HAase) with the IC50 values of 1.06 ± 0.01μg/mL and 12.22 ± 0.39μg/mL, indicating higher inhibitory effect than positive control of aspirin of 6.33 ± 0.05μg/mL (p < 0.01), and comparable inhibitory effect with indometacin of 0.60 ± 0.03μg/mL, and ascorbic acid of 11.03 ± 0.41μg/mL (p > 0.05), respectively. Furthermore, kinetic assays with Lineweaver-Burk plot (Michaelis Menten equation) suggested that CIFE reversibly inhibited the COX-2 and HAase, with a mixed characteristics of competitive and non-competitive inhibition. Thereafter, multi-target affinity ultrafiltration liquid chromatography-mass spectrometry (UF-LC/MS) method was employed to fast fish out the potential COX-2 and HAase in CIFE. Herein, 13 components showed various affinity binding degrees to the COX-2 and HAase, while those components with relative binding affinity (RBA) value higher than 3.0, such as linarin and chlorogenic acid isomers, were deemed to be the most bioactive components for the anti-inflammatory and SS improvement activities of CIFE. Finally, the interaction mechanism, including binding energy, inhibition constant, docking sites, and the key amino acids involved in hydrogen bonds between the potential ligands and COX-2/HAase were simulated and confirmed with the molecule docking analysis. In summary, this study showcased the prominent anti-inflammatory and SS improvement activities of CIF, which would provide further insights on this functional medicinal plant to be a natural anti-SS remedy.

Sensitivity of different organs and tissues as biomarkers of oxidative stress in juvenile tambaqui (Colossoma macropomum) submitted to fasting

The present study was conducted to evaluate the effects of fasting on responses of oxidative biomarkers and antioxidant defenses using different organs and tissues of Colossoma macropomum. The fish were divided into two groups: fed (control) and fasting (7 days). After 7 days, the fish were sampled for assessment of oxidative stress biomarkers (MDA-lipid peroxidation and PCO-protein carbonyl) and antioxidant defenses (SOD-superoxide dismutase; CAT-catalase; GPX-glutathione peroxidase; and GST-glutathione-S -transferase) in the liver, intestine, gills, muscle, brain, and plasma. The results showed an increase in MDA, PCO, SOD, and GPX concentrations in the liver and intestine of fasting fish. In contrast, in the branchial tissue, there was a reduction in the activity of SOD and CAT enzymes in fasting fish. There was also a reduction in CAT activity in the muscle of fasting fish, while in the brain, there were no changes in oxidative stress biomarkers. Plasma showed a relatively low antioxidant response. In conclusion, our results confirm that a 7-day fasting period induced tissue-specific antioxidant responses, but the increase in antioxidant responses was only for the SOD and GPX enzymes of the liver and intestine. Additionally, the liver and intestine were the most responsive tissues, whereas the plasma was the least sensitive to oxidative stress.

Response to visual and mechano-acoustic predator cues is robust to ocean warming and acidification and is highly variable in European sea bass

Predator-prey interactions and, especially, the success of anti-predator responses are modulated by the sensory channels of vision, olfaction, audition and mechanosensation. If climate change alters fish sensory ability to avoid predation, community dynamics can be affected. We investigated whether mid-duration exposure to warming and/or acidification alters behavioural response to visual or mechano-acoustic predator cues in juvenile Dicentrarchus labrax. We measured kinematic variables before and after a visual or a mechano-acoustic challenge which mimicked an overflying bird shadow or a bird swoop attack, respectively. Due to large interindividual variability in responses before cue presentation, fish were categorized as slow and fast to account for baseline individual variability. Treatment did not impact kinematic variables as both slow and fast fish of every treatment elicited precautionary and escape responses. Interestingly, even slow fish swam as fast as fast fish after the cue, suggesting that regardless of initial category, fish managed to escape facing a danger. Anti-predator response varied according to the level of threat to survival with greater responses elicited after the swoop attack. Although wild juvenile sea bass aggregate in schools, school dynamics rely on single leaders which highlights the importance of the variability in individual behaviours. We demonstrated that anti-predator response in juvenile D. labrax is robust to mid-duration exposure to independent and combined effects of warming and acidification. If robustness is confirmed over long-duration, it could provide D. labrax with an evolutionary advantage in the future ocean, where cue transmission through changing environments can further modulate cue perception and predator-prey interactions.

Recording central nervous system responses of freely-swimming marine and freshwater fishes with a customizable, implantable AC differential amplifier

BackgroundFish have adapted to a diversity of environments but the neural mechanisms underlying natural aquatic behaviors are not well known. New methodWe have developed a small, customizable AC differential amplifier and surgical procedures for recording multi-unit extracellular signals in the CNS of marine and freshwater fishes. ResultsOur minimally invasive amplifier allowed fish to orient to flow and respond to hydrodynamic and visual stimuli. We recorded activity in the cerebellum and optic tectum during these behaviors. Comparison with existing methodsOur system is very low-cost, hydrodynamically streamlined, and capable of high-gain in order to allow for recordings from freely behaving, fast fishes in complex fluid environments. ConclusionsOur tethered approach allows access to record neural activity in a diversity of adult fishes in the lab, but can also be modified for data logging in the field.

Learning Like “Fast Fish”: A Research Review on the Promise of Contextualized Agency

In this review, we use the metaphor of a “fast fish” to illustrate the importance of contextualized agency, which assumes that learners must (a) be centrally agentive in their own learning; (b) be able to act on and modify the cognitive, physical, social, and emotional contexts of their learning to support their best performance; and (c) understand learning principles related to human cognitive, social, and emotional architecture. A close analysis of two areas of research—feedback and transfer—illuminates how the relationships between agency and context have been treated in the literature and what features of each are well explored. We consider how contextualized agency manifests in prominent pedagogies and offer suggestions for future research and educational practice.

Abstract 440: Diet and supplement use changes among male cancer survivors during the COVID-19 pandemic

Abstract Introduction: The COVID-19 pandemic has disrupted the lives of cancer survivors who may be at higher risk than people without cancer of other adverse health outcomes. For many individuals, a cancer diagnosis leads to lower physical activity and change in mental health status. Modifiable health behaviors, such as consumption of a healthy diet, can positively affect cancer survivorship outcomes. Aim: To investigate the individual-level changes in diet and supplement use among male cancer survivors during the COVID-19 pandemic and compared to men without cancer. Methods: Participants of the Health Professionals Follow-up Study, enrolled since 1986, were asked to self-report health behaviors during the pandemic on three web-based questionnaires administered during the COVID-19 pandemic (baseline COVID: October 2020, first follow-up: January 2021, second follow-up: April 2021). Diet and supplement use were analyzed descriptively between cancer survivors and individuals without a history of cancer. Further, outcomes were dichotomized to reflect whether a change was healthful or unchanged/unhealthful; for example, lower fast food consumption was classified as a healthful change. To assess the associations between cancer survivors and other men, logistic regression was used, adjusting for age, race, pre-pandemic body mass index, pre-pandemic physical activity, and other health information. Results: Of 4,416 men who completed the baseline COVID-19 questionnaire, 962 were cancer survivors (after excluding those with non-melanoma skin cancer). Across all eligible men (median age: 78 years), there were considerable proportions of men engaging in healthful changes following the start of the pandemic in intake of fast food (19% decreased), sugary drinks (14% decreased), fresh fruit (26% increased), fresh vegetables (19% increased), fish (13% increased), and red meat (12% decreased) consumption. Similar changes in diet were reported on the second follow-up questionnaire. For most foods, a similar percentage of cancer survivors and individuals without a history of cancer increased healthy eating. Findings from multivariable logistic regression models were reflective of higher odds of cancer survivors to engage in a healthful diet change for unhealthy food categories (i.e., less fast food, less frozen food), though none of which were statistically significant. There was little change in supplement use during the pandemic, except for 6% who started use of vitamin D supplements between the baseline and first follow-up questionnaire. Conclusion: Our findings suggest that older men engaged in healthful diet changes during the COVID-19 pandemic, without noticeable differences among cancer survivors. Citation Format: Alaina H. Shreves, Colleen B. McGrath, Konrad Stopsack, Lilian Cheung, Ann Fisher, Edward Giovannucci, Sarah Markt, Eric Rimm, Lorelei Mucci. Diet and supplement use changes among male cancer survivors during the COVID-19 pandemic [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 440.

Coupling of Bio-Reactors to Increase Maximum Sustainable Yield

In the field of fisheries management, the objective is to obtain an optimal catch while maintaining the fishery resource at a sufficiently high level to avoid the extinction of the exploited species. In mathematical fishery models, the fishing effort that must be implemented to have a sustainable fishery with a maximum harvest rate in the long term is sought. This goal is called the “Maximum Sustainable Yield” (MSY). In the chemostat, the substrate can be seen as prey of which the predator is the product. MSY search is thus extended to the classical chemostat model with a Monod function. There exists a dilution rate that maximizes the product synthesis. The study is extended to the case of the gradostat with fast substrate and product exchanges between two coupled bioreactors. The existence of two time scales makes it possible to apply methods of aggregation of variables to derive a reduced model governing a few global variables describing the dynamics of the complete system at the slow time scale. The analysis of the mathematical aggregated model is performed. Existence of equilibria as well as local and global stability are studied. The overall product yield in the system of coupled bioreactors may be greater than the sum of the yields of the two uncoupled bioreactors, i.e., if they functioned without connection between them. The increase in product yield is all the more important as the distribution of the substrate and of the product is asymmetrical between the two coupled bioreactors. The model is applied to fish farming by considering the coupling of two breeding sites. Here again, the model makes it possible to find the fast fish exchanges that must be established between the two breeding basins to optimize the overall yield of the farm.

Influence of light indicators on the development of Clarias gariepinus during early ontogenesis

High-quality and fast fish farming is very relevant and in demand nowadays. The african clary catfish is one of the representatives of aquatic organisms, which makes it possible to study complete embryogenesis in a short time in order to understand what favorable environmental conditions are necessary to obtain a larger volume of marketable fish. The aim of our study is to study the early stage of ontogenesis of Clarias gariepinus under the influence of changes in the degree of illumination of the environment. The material for the study was eggs obtained from females at the age of 2 years. The incubation was carried out on special mesh trays located on the surface of the pools. A total of 91000 eggs were laid for incubation. The eggs were fertilized by artificial insemination. The fertilized eggs were kept at an optimum temperature of 28,5°C. The first group was incubated in the dark, and the second under fluorescent lamps. Every 5-15 minutes, eggs were placed in a Petri dish and the material was counted and photographed using a digital camera.The results of our research showed that 20 minutes after fertilization, the onset of blastodisc formation was recorded in both groups. After 35 minutes, cell cleavage begins. The duration of this period is considered from the moment of cleavage until the complete overgrowth of the embryonic disc with cells. After 80 minutes, further division of the embryonic cell occurs with the formation of a spherical structure - morula, as well as the overgrowth of the yolk with the embryonic layer. Later 15 hours, after fertilization, we found that the development of the embryo occurs evenly, with positive dynamics, regardless of illumination.An analysis of the results obtained allows us to conclude that changes in light parameters do not have a negative effect on the rate of development of the Clarias gariepinus eggs.

Environmentally triggered shifts in steelhead migration behavior and consequences for survival in the mid-Columbia River.

The majority of Columbia River summer-run steelhead encounter high river temperatures (near or > 20°C) during their spawning migration. While some steelhead pass through the mid-Columbia River in a matter of days, others use tributary habitats as temperature refuges for periods that can last months. Using PIT tag detection data from adult return years 2004-2016, we fit 3-component mixture models to differentiate between "fast", "slow", and "overwintering" migration behaviors in five aggregated population groups. Fast fish migrated straight through the reach on average in ~7-9 days while slow fish delayed their migration for weeks to months, and overwintering fish generally took ~150-250 days. We then fit covariate models to examine what factors contributed to the probability of migration delay during summer months (slow or overwintering behaviors), and to explore how migration delay related to mortality. Finally, to account for the impact of extended residence times in the reach for fish that delayed, we compared patterns in estimated average daily rates of mortality between migration behaviors and across population groups. Results suggest that migration delay was primarily triggered by high river temperatures but temperature thresholds for delay were lowest just before the seasonal peak in river temperatures. While all populations groups demonstrated these general patterns, we documented substantial variability in temperature thresholds and length of average delays across population groups. Although migration delay was related to higher reach mortality, it was also related to lower average daily mortality rates due to the proportional increase in reach passage duration being larger than the associated increase in mortality. Lower daily mortality rates suggest that migration delay could help mitigate the impacts of harsh migration conditions, presumably through the use of thermal refuges, despite prolonged exposure to local fisheries. Future studies tracking individual populations from their migration through reproduction could help illuminate the full extent of the tradeoffs between different migration behaviors.

RNA-Seq Transcriptome Analysis of the Liver and Brain of the Black Carp (Mylopharyngodon piceus) During Fasting.

The black carp (Mylopharyngodon piceus) is an important carnivorous freshwater-cultured species. To understand the molecular basis underlying the response of black carp to fasting, we used RNA-Seq to analyze the liver and brain transcriptome of fasting fish. Annotation to the NCBI database identified 66,609 unigenes, of which 22,841 were classified into the Gene Ontology database and 15,925 were identified in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Comparative analysis of the expression profile between fasting and normal feeding fish revealed 13,737 differentially expressed genes (P<0.05), of which 12,480 were found in liver tissue and 1257 were found in brain tissue. The KEGG pathway analysis showed significant differences in expression of genes involved in metabolic and immune pathways, such as the insulin signaling pathway, PI3K-Akt signaling pathway, cAMP signaling pathway, FoxO signaling pathway, AMPK signaling pathway, endocytosis, and apoptosis. Quantitative real-time PCR analysis confirmed that expression of the genes encoding the factors involved in those pathways differed between fasting and feeding fish. These results provide valuable information about the molecular response mechanism of black carp under fasting conditions.

Physiological trade-offs associated with fasting weight loss, resistance to exercise and behavioral traits in farmed gilthead sea bream (Sparus aurata) selected by growth

Three gilthead sea bream families representative of slow, intermediate and fast heritable growth in the Spanish PROGENSA® selection program were used to uncover the effects of such selection on energy partitioning through measurements of fasting weight loss, swimming performance and behavioral traits in one- and two-year-old fish. Firstly, selection for fast growth significantly increased fasting weight loss and decreased the hormonal ratio of circulating Igf-i/Gh in short-term fasting fish (17 days). This is indicative of a stronger negative energy balance that explains the reduced compensatory growth of fast-growing fish during the subsequent short-term refeeding period (7 days). Selection for fast growth also decreased the critical speed (Ucrit, 6–7 BL s−1) at which fish become exhausted in a swim tunnel respirometer. The maximum metabolic rate (MMR), defined as the maximum rate of oxygen consumption during forced exercise, was almost equal in all fish families though the peak was achieved at a lowest speed in the fast-growing family. Since circulating levels of lactate were also slightly decreased in free-swimming fish of this family group, it appears likely that the relative energy contribution of anaerobic metabolism to physical activity was lowered in genetically fast-growing fish. Selection for heritable growth also altered activity behavior because slow-growing families displayed an anticipatory food response associated with more pronounced daily rhythms of physical activity. Also, respiratory frequency and body weight showed and opposite correlation in slow- and fast-growing free-swimming fish as part of the complex trade-offs of growth, behavior and energy metabolism. Altogether, these results indicate that selective breeding for fast growth might limit the anaerobic fitness that would help to cope with limited oxygen availability in a scenario of climate change.

A simple modelling tool for assessing interaction with host and local infestation of sea lice from salmonid farms on wild salmonids based on processes operating at multiple scales in space and time

Sea lice are marine ectoparasitic crustacea which limit the potential for sustainable salmon aquaculture due to risks of impacts on iconic wild salmon and sea trout. Control of the parasite on farms costs an estimated 9% of farm revenue. Sea lice develop through planktonic nauplii to copepodid stages which attach to, and mature on, salmonid hosts until females become ovigerous (egg laying) Impacts of lice on wild fish depend on their exposure to planktonic larval lice transported from salmon farms, which consists of (A) production of larval lice from ovigerous female lice on salmon farms, (B) local concentrations of planktonic larval lice infectious copepodids in adjacent waters, (C) rates of infestation of wild fish given these concentrations, and (D) impact on fish given this level of interaction. A model of this local exposure around salmon farms was developed. Production rates for nauplii as a function of the numbers of adult lice on salmon farms and maturation to copepodids (A) is well studied, as are impacts of infestation (D), with >0.75 lice per gram of host fish considered to present a high risk of mortality. Using existing assessments of infectious copepodid production (A) we develop a model of copepodid concentration (B) based on a simple kernel of copepodid distribution around farms; within this kernel the copepodids are assumed either to disperse evenly or to be transported in a concentrated plume, allowing comparison of the range of different concentration distributions. These distributions combine with a model of infestation (C) based on small-scale movements of copepodids in the immediate vicinity of a swimming fish. Fish swimming at intermediate velocities are most susceptible to infestation, as slow fish exhaust lice in their immediate vicinity while fast fish move on before lice copepodids can approach. These models are combined to create an assessment of the risk that concentrations can result in infestation of fish at levels considered to cause mortalities (D). The results can be used in combination with empirical assessments as a tool to link potential impacts on wild salmonids to aquaculture biomass and on-farm lice management in different environments in support of strategic aquaculture planning. Our modelling demonstrates the, often neglected, importance of fine-scale processes in sea lice infestation of salmonids.

Estimating oxygen consumption of rainbow trout (Oncorhynchus mykiss) in a raceway: A Precision Fish Farming approach

The Precision Fish Farming (PFF) approach was applied to the estimation of fish oxygen consumption of rainbow trout in a raceway farm. A dynamic model, simulating the evolution of Dissolved Oxygen concentration, was identified: the daily oscillation of fish oxygen consumption rate was simulated by means of a sinusoidal function. The model was applied to the data set collected during a four-week field study, which was carried out in July 2019. Water temperature and Dissolved Oxygen concentration were measured with an hourly frequency in farm influent and effluent. Fish biomass was monitored on a daily basis by combining the data provided by a state-of-the art system for non-invasive estimation of fish weight distribution with mortality counting. The monitoring period was partitioned into two time-windows, as fish was not fed during the first two weeks. These windows were further partitioned into a calibration and validation set. Three model parameters, i.e. the average daily respiration rate, the amplitude of its daily oscillation, and its phase were estimated by fitting the model output to the time series of DO concentration in the effluent. The results of the calibration show that: 1) the daily average oxygen consumption rate is consistent with the literature; 2) the amplitude of the daily oscillation when fish is regularly fed is more than twice that estimated for fasting fish. The results of the validation suggest that the model could be used to implement a cost-effective automatic control of oxygen supply, based on the short-term prediction of oxygen demand.

Life histories determine divergent population trends for fishes under climate warming

Most marine fish species express life-history changes across temperature gradients, such as faster growth, earlier maturation, and higher mortality at higher temperature. However, such climate-driven effects on life histories and population dynamics remain unassessed for most fishes. For 332 Indo-Pacific fishes, we show positive effects of temperature on body growth (but with decreasing asymptotic length), reproductive rates (including earlier age-at-maturation), and natural mortality for all species, with the effect strength varying among habitat-related species groups. Reef and demersal fishes are more sensitive to temperature changes than pelagic and bathydemersal fishes. Using a life table, we show that the combined changes of life histories upon increasing temperature tend to facilitate population growth for slow life-history populations, but reduce it for fast life-history ones. Within our data, lower proportions (25–30%) of slow life-history fishes but greater proportions of fast life-history fishes (42–60%) show declined population growth rates under 1 °C warming. Together, these findings suggest prioritizing sustainable management for fast life-history species.

Abstract 4256: Multiplex fast FISH assay for detecting ROS1, RET and MET aberrations in FFPE specimens using BioView image analysis

Abstract Background: Biomarker testing in lung cancer is often limited by a lack of sufficient formalin fixed, paraffin embedded (FFPE) tissue for comprehensive genomic profiling. To promote personalized therapy for lung cancer, a multiplex FISH assay was developed to simultaneously assess aberrations in ROS1, RET, and MET on a single FFPE specimen slide. Methods: Specimens included primary tumor (N = 39) as well as biopsies from a variety of metastatic sites (N = 16). These included 12 samples with ROS1 rearrangements, 3 samples with RET rearrangements, and 11 samples with MET amplification reported by a previously validated laboratory test method. A probe mix contained 6 differentially labeled fluorescent probes: 3' ROS1, 5' ROS1, 3' RET, 5' RET, MET and CEP7. The probes were formulated in Vysis IntelliFISH Hybridization Buffer to allow for a 2 h hybridization time. BioView imaging platform and Duet software algorithm were used to perform automated slide scanning and digital analysis. Specimens were considered positive for ROS1 or RET rearrangement if &amp;gt;15% evaluated cells contained a break apart (rearranged) signal. Specimens were considered positive for MET amplification if &amp;gt;15% of cells had MET/CEP7 ratio &amp;gt;2 and positive for polysomy if &amp;gt;15% of cells had 5 or more MET signals copies. Results: The 6 color FISH assay was 97% concordant for ROS1 rearrangement and 100% concordant for RET rearrangement. The average background percentage of positive tumor cells in cases without known gene rearrangements was approximately 5%, yielding a negative cutoff threshold of approximately 15%, in accordance with cutoff thresholds reported in literature. The 6 color FISH assay was 91% concordant for MET amplification or polysomy. Results were interpretable for 98% of targets analyzed by the 6 color FISH method. Four samples failed on analysis for one of the targets due to lack of sufficient cells or lack of adequate hybridization signal. Conclusion: A newly developed 6-color FISH assay allows simultaneous detection of three genomic abnormalities using only 1 specimen slide. This feature combined with rapid hybridization in IntelliFISH buffer and automated BioView slide imaging and analysis can significantly increase the yield of molecular testing on limited lung cancer tissue samples. Careful pathologic correlation for tumor cell identification and careful assessment of hybridization quality are necessary to optimize the accuracy of this test method. Citation Format: Irina A. Sokolova, Patrick Bedroske, Tatyana A. Grushko, Amber R. Schneider, Kristine Jacobson, Jesse S. Voss, Yishay Tauber, Yossi Avisror, Vitaliy Shkolnik, Katerina Pestova, Katherine B. Geiersbach. Multiplex fast FISH assay for detecting ROS1, RET and MET aberrations in FFPE specimens using BioView image analysis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4256.

Abstract P362: Metabolomic Markers of Southern Dietary Patterns in the Jackson Heart Study

Background: Diet is an important modifiable risk factor for hypertension and other chronic diseases. New biomarkers are needed for the objective assessment of dietary intake. The aim was to investigate metabolites associated with Southern dietary patterns. Methods: We used available dietary and metabolomics data from 1,042 Jackson Heart Study participants, a population of African-American men and women in Jackson, Mississippi, to determine metabolites associated with Southern dietary patterns. Three dietary patterns were empirically derived using factor analysis: meat and fast food, fish and vegetables, and starchy foods. Multivariate regression models were adjusted for age, sex, education, smoking status, physical activity, alcohol consumption, multi-vitamin use, kidney function, body mass index, and batch. We randomly selected two subsets of the study population: 2/3 sample for discovery (n=683) and 1/3 sample for validation (n=359). False discovery rate (FDR) was used to account for multiple comparisons in the analysis of the discovery sample and α=0.05 was used to assess statistical significance in the validation sample. Results: Among the 357 metabolites analyzed, one was associated with the meat and fast food dietary pattern (proline betaine), ten were associated with the fish and vegetables dietary patterns [1,7-dimethyluric acid, caffeine, C22:6 lysophosphatidylethanolamine (LPE), C38:6 phosphatidylethanolamine (PE), C38:7 phosphatidylcholine plasmologen, C38:7 PE plasmalogen, N-acetylornithine, NH4 C38:5 diacylglycerol or triacylglycerol fragment, pantothenate, and pantothenic acid], and none were associated with the starchy foods dietary pattern (all FDR&lt;0.05). Two metabolites remained statistically significantly associated with dietary patterns in the validation sample: proline betaine and meat and fast food (β: -0.16, 95% CI: -0.30, -0.01, p=0.03) and C22:6 LPE and fish and vegetables (β: 0.12, 95% CI: 0.01, 0.23, p=0.03). Conclusion: Two potential biomarkers (proline betaine and C22:6 LPE) were discovered and replicated in association with dietary patterns detected in a Southern U.S. African-American population.

Analisis Pendapatan dan Pemasaran Pekebak Ikan (Pelet Keong Bakau Pakan Ikan) di Kota Langsa

Pellets are a source of energy intake made by humans with certain compositions needed according to an aquatic organism. The need for artificial feed (pellets) will greatly support the success of cultivation. A good pellet will produce fast fish growth so the production costs are not too high. Feed on a fish is not the same because it must be adapted to the type of commodity and its eating habits. Good food is a food that has high protein and is easily obtained. One of them is mangrove snails (T. telescopium). Kuala Langsa is a village located in the city of Langsa which is directly adjacent to the Malacca Strait so that in this area mangroves are found. The advantage of this pellet is that it is easy to find mangrove snail base material and its availability is abundant so that later the price will be cheaper with higher quality protein content compared to the pellets available on the market. The benefits of making this pellet are: (1). The creation of quality fish feed pellets, as an alternative to fish feed. (2). As an application of the science of fish feed from college, and (3). As an application of entrepreneurship science, to hone skills and soft skills entrepreneurs, so that they are ready to become independent entrepreneurs when they graduate. This pellet has a value of R / C ratio of 1.33, which means that every capital issued in the amount of Rp. 100.00 will get an income of Rp. 137.00. Thus, the fish pellet feed business is feasible to be developed.

Fasting combined with long catch duration modifies the physio‐metabolic response and flesh quality of rainbow trout

Pre-slaughter handling involves fasting fish and catching them, which can affect fish welfare and flesh quality, but few studies have considered their combined effects. In this study, adult rainbow trout (320 ± 10 g average weight) were fasted for 7 days (135.6 degree days) and subjected to a long catch duration (20 min), compared with controls (no fasting or short catch duration). Condition factor, organ weight indexes and carcass yield decreased with fasting but not catch duration. Plasma concentrations of cortisol, glucose and lactate increased after a long catch, while plasma triglycerides decreased with fasting. Liver glycogen concentration was lower in fasted fish, and liver luminosity and chroma were higher after fasting with a long catch. Regarding flesh quality, rigor mortis resolved more slowly and final muscle pH at 48 hr post-mortem was higher for fasted fish with a long catch time. Muscle glycogen concentration was higher in fasted fish, where chroma was also lower. Fasted fish had lower lipid oxidation, but there were no differences in fat content in muscle. Fasted fish with a long catch duration also had less monounsaturated and more saturated fatty acids. In conclusion, a long catch triggered a stress response that had negative effects on flesh quality, independently of fasting.

Effect of food deprivation on neuropeptide Y immunoreactivity and concurrent biochemical and gonadal responses in tilapia Oreochromis mossambicus (Peters, 1852)

The effect of short- and long-term fasting on neuropeptide Y (NPY) secreting neurons in the brain and concurrent biochemical and gonadal responses were determined in the cichlid fish Oreochromis mossambicus (Peters, 1852). Exposure of fish to fasting for 6 or 12 days resulted in intensely stained NPY-immunoreactive neurons in the nucleus entopeduncularis and the nucleus preopticus regions of the brain in contrast to moderately stained neurons in control fishes, whereas food supplementation after 6 days starvation restored NPY-immunoreactive profile to the same state as in control groups in both male and female fish. The gonadosomatic index remained significantly lower in female fishes subjected to fasting alone as well as fasting followed by refeedings compared to controls. While the hepatosomatic index (HSI) also showed a significant decrease in fasting male and female fish compared to controls, it increased subsequently in fishes exposed to refeeding after starvation. In addition, a significant decrease in the serum levels of glucose and triglycerides as well as the hepatic tissue protein content in fasting fish compared to those of controls in both sexes suggested gluconeogenesis. Although the serum levels of glucose and triglycerides were reinstated in both males and female fishes subjected to starvation and refeeding, the hepatic tissue protein levels were not completely restored in females. Collectively, these results suggest that food-deprivation, either for short or long term duration, significantly increases the secretory activity of NPY neurons in the brain concomitant with a significant decrease in the serum levels of glucose and triglycerides, the hepatic tissue protein content and the GSI in both sexes. Although males recovered from the effects of starvation following refeeding, females appeared to be more vulnerable to the effects of fasting.