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A fish intestinal in vitro model for investigation of lipid metabolism and steatosis
Full text linkCholine is now recognized as an essential nutrient to ensure lipid transport in Atlantic salmon. Its deficiency leads to excessive lipid accumulation in the enterocytes, a condition known as steatosis. The knowledge of lipid metabolism and steatosis in fish remains limited, motivating the use of in vitro intestinal models to perform deeper explorations. This study aimed to create an in vitro steatosis model using RTdi-MI, a new cell line derived from the distal intestine of rainbow trout. Cells were exposed to varying oleic acid (OA) concentrations over different time points (24 h, 72 h, and 168 h). Results indicated that the increasing OA concentration enhanced intracellular lipid droplet formation. Quantitative lipid analysis confirmed OA accumulation, which intensified with prolonged exposure and increased OA dose. Moreover, all cells, including controls, exhibited fatty acid metabolic activity. Such outcome was confirmed by light and fluorescence microscopy. Additionally, RTdi-MI cells expressed genes involved in lipid metabolism and synthesis similar to in vivo conditions. Collectively, our findings demonstrate the ability of RTdi-MI cells to accumulate OA in intracellular lipid droplets and mirror in vivo steatosis conditions, offering a new tool for exploring fish intestinal lipid metabolism.publishedVersio
Selective genotyping strategies for genomic selection for host resistance against pancreatic disease in A. salmon
Full text linkGenomic selection has become an increasingly important tool for improving aquaculture breeding programs, but the high cost of genotyping has been a barrier. Selective genotyping of phenotypically contrasting individuals is an approach that can reduce genotyping costs without significantly compromising the prediction accuracy. The aim of the study was to assess the effect of selective genotyping strategies on prediction accuracy and bias using linear and nonlinear genomic models in silico. The genotype and phenotype data from 7298 individuals belonging to 348 full-sib families were used from Mowi's Atlantic salmon commercial breeding population. A binary phenotype was generated from a challenge experiment to measure resistance to pancreatic disease (PD). Five selective genotyping strategies were tested: Full Genotyping (FG), Top-Bottom Genotyping (TBG), Minor Category Genotyping (MCG), Random Across family genotyping (RAFG), and Random Within family Genotyping (RWFG). Use of genomic linear models, GBLUP families, and non-linear models (Bayesian approaches) compared within the context of selective genotyping strategies. The prediction accuracies of the different genotyping strategies ranged between 0.44 and 0.87. Compared to the FG strategy, a 3–8% reduction in prediction accuracy was observed for the TBG, RAFG and RWFG approaches for the various genomic models. Differences among the TBG, RAFG and RWFG genotyping strategies were generally small. However, when the number of selected sibs for genotyping becomes below 8 per family, genotyping of the most phenotypically extreme individuals within a family is more advantageous. The Bayesian methods exhibited slightly higher prediction accuracy when 8 or more siblings per family were genotyped. However, as the number of training siblings per family decreased below 8, the single-step GBLUP methods performed slightly better. Adoption of single-step GBLUP has proven effective in mitigating the reduction in prediction accuracy and the increase in bias when selectively genotyping a subset of test siblings within the RAFG, RWFG, and TBG strategies.publishedVersio
Unifying heterogeneous hyperspectral databases for in vivo human brain cancer classification: Towards robust algorithm development
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Pea-Derived Raffinose-Family Oligosaccharides as a Novel Ingredient to Accelerate Sour Beer Production
Full text linkThis study investigated raffinose family oligosaccharides (RFOs) derived from pulses as selective carbon sources for sour beer production. Fourteen lactic acid bacteria (LAB) were screened for growth in media supplemented with RFOs. Furthermore, the influence of ethanol and isomerized α-acids on the bacterial growth was investigated. While most LAB grew in the presence of RFOs, few did so in the presence of ethanol and α-acids. Some of the LAB with tolerance to these stressors were then combined with Brettanomyces claussenii to create classic-style sour beers with or without RFOs. These were characterized chemically, physically, and sensorially. Sour beers made with RFOs were evaluated as being comparable to a commercial Belgian sour beer for some sensory characteristics. Furthermore, the sensory analysis revealed significantly increased acidity levels and differences in flavor and taste between beers fermented with and without RFOs, which was underpinned by chemical analysis. Crucially, beany off-flavors, which are a common problem with pulse-derived ingredients, did not increase upon RFO addition. Thus, by combining selected LAB with RFOs, we successfully utilized a food sidestream and expanded the possibilities for brewing sour beers in a controlled manner in a short time. This is in contrast to the lengthy process used for traditional sour beers.publishedVersio
How Significant Are Marine Invertebrate Collagens? Exploring Trends in Research and Innovation
Full text linkThis review is focused on the research, innovation and technological breakthroughs on marine invertebrate collagens and their applications. The findings reveal that research dates back to the 1970s, and after a period of reduced activity, interest in collagens from several marine invertebrate groups was renewed around 2008, likely driven by the increased commercial interest in these biomolecules of marine origin. Research and development are predominantly reported from China and Japan, highlighting significant research interest in cnidarians (jellyfish), echinoderms (sea cucumbers, sea urchins and starfish), molluscs (squid and cuttlefish) and sponges. Co-word analysis of the literature highlights applications in regenerative medicine, the properties of hydrolysates, and biology and biochemistry studies. Innovation and the technological landscape, however, focus on fewer taxonomic groups, possibly reflecting the challenge of sustainably sourcing raw materials, with a higher number of patents coming from Asia. Globally, jellyfish collagen is the most prominent marine invertebrate source, while Asia also emphasizes the use of collagens derived from molluscs and sea cucumbers. Europe, despite fewer patents, explores a broader range of taxonomic groups. Globally, key applications registered are mostly in medical, dental and toiletry areas, with peptide preparations spanning multiple animal groups. The food domain is notably relevant for molluscs and sea cucumbers. Market trends show a strong presence of cosmetic and supplement products, aligning with market reports that predict a growing demand for marine collagens in cosmetics and personalized nutrition, particularly in targeted health supplements.publishedVersio
Prediction of the salmon lice density on wild sea trout from the mean predicted lice density in the sea: A cross-validation of the data in Myksvoll et al. (2018)
Full text linkThe coast of Norway is divided into 13 production zones (PZ 1–13) for farmed Atlantic salmon and rainbow trout. In the “Traffic Light System” (TLS) the increased mortality risk due to lice infestation on wild migrating smolt determines whether the production at the grow-out farms in a PZ must be reduced (Red light), can remain at the current level (Yellow), or can be increased (Green). Myksvoll et al. (2018) analysed observed mean lice burden per gram body weight (OMLB) of wild sea trout caught using traps and nets at 102 locations each of grid size 15 × 15 grid; i.e., 12 km × 12 km =144 km2) along the coast and the predicted mean lice particle density in the sea (PMLD) at these locations.. They concluded, based on a Spearman rank correlation of 0.72 between log of the PMLD and OMLB values, that PMLD provide reliable information about the spatial distribution of salmon lice infestation pressure all along the coast and therefore of importance for the knowledge base of TLS. Cross-validation of their data with linear regression models, bivariate logistic regression models, and a threshold model with three assumed mortality classes (Green, Yellow and Red), do not confirm their conclusions. Rather, the very low predictive power of all models shows that PMLD is such a poor predictor of OMLB that assigning a Green, Yellow or Red colour to a PZ with a sufficiently high statistical power is only possible with PMLD values from many sea areas in sum larger than the area of the majority of the 13 PZs.publishedVersio
Facilitated identification of bioactive peptide fractions and optimization of enzymatic protein hydrolysis using size-exclusion chromatography fingerprints: Combining interval PLS and response surface modeling
Full text linkProtein hydrolysates made from food industry byproducts have the potential to be used as nutraceuticals that can alleviate high blood pressure, by inhibiting angiotensin converting enzyme I (ACE-I). Discovery and optimization of bioactive peptide fractions, in typically complex protein hydrolysates, is a laborious and time-consuming task. In the present study, a library of 108 hydrolysates were produced from mechanical deboning chicken residue, using three different temperatures, four protease concentrations and nine hydrolysis times, in a full factorial manner. Employed design of experiment enabled a thorough screening of the experimental space and resulted in hydrolysates with substantial variation in bioactivity. Hydrolysates were characterized by size-exclusion chromatography and by in vitro ACE-I inhibition assay. To identify a bioactive fraction, interval-partial least square (iPLS) regression based on a chromatographic fingerprint of a crude samples was used, which eliminated the need for time-consuming bioassay-guided fractionation. After the bioactive fraction was identified, the response surface modeling (RSM) was employed to develop a predictive model for the optimization of hydrolysate properties by adjusting the production parameters. Here we are presenting a novel methodology combining: (1) SEC fingerprint-based iPLS for facilitated identification of bioactive peptide fractions, and (2) RSM using the identified SEC fractions as a response for a robust optimization of the hydrolysis process. A combination of iPLS and RSM utilizing chromatographic fingerprints was demonstrated as a promising analytical approach that can facilitate discovery of bioactive peptides in complex hydrolysates and further enable optimization of production conditions.publishedVersio
The effect of season, somatic cell count and bulk milk storage time on the sensory and chemical characteristics of an aged hard goat milk cheese
Full text linkThis study investigated the impact of seasonality (lactation stage), milk storage time and somatic cell count (SCC) on the chemical ripening and sensory characteristics of hard goat milk cheese ripened for 12–18 months. Milk was collected from four farms at four stages: indoor feeding (A), mountain pasture release (B), high summer pasture (C), and lowland pasture during oestrus (D). Cheeses were produced the following- and three days after delivery. Quantitative Descriptive Analysis (QDA) revealed significant seasonal differences in sensory attributes. Cheeses from season C and D exhibited more ‘sweet taste’ and ‘caramel flavour’, while those from season A had more ‘oxidized odour’ and ‘acidic taste’. Season C and D cheeses had higher levels of total free amino acids (FAA), and a stickier, more cohesive texture compared to the drier, grittier texture of season A cheeses. The results indicate that season and bulk milk storage time have a greater effect on cheese sensory and chemical properties than SCC, although SCC did have an impact. Developing production protocols that consider seasonal variation (lactation stage) and SCC, is essential to optimise cheese quality standardisation, benefiting small-scale artisanal and industrial goat cheese producers.publishedVersio
Cardiac implications of chicken wooden breast myopathy
Full text linkIntroduction: Wooden breast disease is a myopathy of the skeletal muscle in chickens of commercial breeding. Although the underlying pathophysiology remains unknown, we and others have previously shown that affected broilers display varying degrees of fibrosis, extracellular matrix (ECM) remodeling, inflammation, and alterations in various molecular signaling pathways. Other myopathy conditions, such as Duchenne muscular dystrophy, also affect the cardiac muscle and are associated with fibrosis and reduced cardiac function. To determine potential cardiac implications of wooden breast disease and identify whether molecular and fibrotic changes were similar to what we have previously found in the breast, we have investigated the hearts of commercial Ross 308 broilers. Methods: Hearts from male Ross 308 broiler chickens from mildly and severely wooden breast-affected chickens categorized in previous studies were analyzed. Ventricles from the hearts were analyzed by immunoblotting, real-time qPCR, near-infrared spectroscopy, Raman spectroscopy, and Masson`s trichrome histology. RNA sequencing was also conducted to identify the molecular footprint of the mildly and severely wooden breast-affected chickens. Results: Compared to mildly affected chickens, the severely wooden breast-affected chickens did not show an increase in heart weight, water-binding capacity, or macronutrient composition. The hearts did also not display any differences in fibrosis development, extracellular matrix gene expression, or typical cardiac and inflammatory markers. The severely affected chickens did, however, show a reduction in protein levels of biglycan and fibromodulin, as well as alterations in matrix metalloproteinase 2, Wnt ligands, mTOR signaling, heat shock protein 70, and muscle LIM protein. Functional enrichment analysis of RNA sequencing also suggested a different molecular footprint of biological processes and pathways between the two groups. Conclusion: Hearts from wooden breast-affected chickens did not display the same fibrotic alterations as those previously found in the breast. Despite few alterations detected in the markers and signaling molecules tested, RNA sequencing indicated a different molecular footprint in the hearts of severely compared to mildly wooden breast-affected chickens.publishedVersio
Protocol: Assessment of the shelf-life for table eggs
Full text linkIn connection with regulatory development under the European Commission and the preparation of a possible text adapted to/influencing of new changes in the animal hygiene regulations, the Norwegian Food Safety Authority has commissioned a knowledge summary and risk assessment related to the shelf life of table eggs in Norway. VKM's Panel for Biological Hazards has established a project group which has developed a protocol for the assessment. The same project group will prepare a draft for the assessment. The assessment will be approved by the Panel of Biological Hazards and is scheduled to be published in January 2025.Protocol: Assessment of the shelf-life for table eggspublishedVersio