In vivo metabolism of unsaturated fatty acids in Sepia officinalis hatchlings

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Effect of type of food and culture density on growth and lipid composition of Seriola dumerili juveniles

The aim of this study was to determine the effect of three different types of food and two stocking densities on growth, survival and lipid composition of muscle and liver of Seriola dumerili juveniles. Juvenile of S. dumerili were randomly distributed in groups of 15 fish/tank (low stocking density, LD) and groups of 25 fish/tank (high stocking density, HD) and fed with three different types of food: commercial pellets for Sparidae (SP), commercial pellets for S. dumerili (SE) and frozen Mackerel (MA). Samples of muscle and liver were taken for lipid analysis at the end of trial (86 days). Fish fed with SP showed growth significantly lower than the groups fed with SE and MA for both stocking densities. Higher survival rates was observed in fish fed diet SE and MA held at LD. Lipid composition analyses revealed important differences between fish fed with different diets but no difference between groups with different stocking density were detected. Total lipid content in muscle and liver from fish fed with SE was very much higher than in fish fed with SP and MA, which was reflected in higher tryglicerides and lower cholesterol contents. The fatty acid composition of tissues clearly reflected the composition of the diet supplied. The groups fed with MA presented the highest proportion of docosahexaenoic acid (DHA), arachidonic acid (ARA) and the lower amounts of eicosapentaenoic acid (EPA). In contrast, fish fed with SE presented the lower amounts of ARA and DHA and higher content in 18:2n-6 specifically in the liver. In consequence, fish fed with MA presented a higher DHA/EPA ratio and a lower EPA/AA ratio in both tissues while the opposite was observed in group SE. These preliminary results indicate that SE diet allows get better performance than SP diet obtaining growth and survival rates comparable to fish fed with MA, although with a higher lipid deposition in tissues

Desarrollo de un alimento cárnico embutido saludable con el agregado de extracto acuoso de propóleo (EAP) como conservante

En los últimos años los consumidores han mostrado interés por productos cárnicos saludables que aporten ingredientes de origen natural, evitando las altas cantidades de sal, grasas y aditivos. Por consiguiente, el objetivo de este trabajo fue producir un embutido saludable reducido en sodio y nitritos con el agregado de extracto acuoso de propóleo (EAP), manteniendo las características similares a un producto tradicional. Se modeló un embutido cárnico reducido en su contenido de NaCl y sin materia grasa adicionada, el cual presentó en la mayoría de los parámetros analizados similitudes con embutidos comerciales. La disminución del contenido de nitrito produjo alteraciones en el color, afectando significativamente el valor del parámetro a* y algunos parámetros de textura. El EAP mostró una buena acción bacteriostática pero no así fungistática, implicando la adición de otro conservante, ya sea natural o no, que ejerza acción sobre dichos microorganismos para alcanzar la vida útil esperada (42 días). Sensorialmente, el producto presentó diferencias significativas con el comercial, pero acaparó la atención de los consumidores. Es factible producir un embutido de bajo contenido en sodio, sin grasa añadida y remplazando el NaNO2 como conservante, que se asemeje a un producto industrializado con buena aceptación del consumidor

International collaborative follow - up investigation of graduating high school students’ understandings of the nature of scientific inquiry: is progress Being made?

Understandings of the nature of scientific inquiry (NOSI), as opposed to engaging students in inquiry learning experiences, are included in science education reform documents around the world. However, little is known about what students have learned about NOSI during their pre-college school years. The purpose of this large-scale follow-up international project (i.e. 32 countries and regions, spanning six continents and including 3917 students for the high school sample) was to collect data on what exiting high school students have learned about NOSI. Additionally, the study investigated changes in 12th grade students’ NOSI understandings compared to seventh grade (i.e. 20 countries and regions) students’ understandings from a prior investigation [Lederman et al. (2019). An international collaborative investigation of beginning seventh grade students’ understandings of scientific inquiry: Establishing a baseline. Journal of Research in Science Teaching, 56(4), 486–515. https://doi.org/10.1002/tea.21512]. This study documents and discusses graduating high school students’ understandings and compares their understandings to seventh grade students’ understandings of the same aspects of scientific inquiry for each country. It is important to note that collecting data from each of the 130+ countries globally was not feasible. Similarly, it was not possible to collect data from every region of each country. A concerted effort was made, however, to provide a relatively representative picture of each country and the world

Fisiología de la nutrición y del estrés en las primeras fases de vida del pulpo común (Octopus vulgaris). Resultados del proyecto OCTOPHYS

El cultivo del pulpo común (Oclopus vulgaris) está severamente limitado por las altas mortalidades que se producen durante su cultivo larvano, aunque en la actualidad, las causas especfficas de tan alta mortalidad siguen siendo desconocidas. Este proyecto pretende adquirir conocimientos básicos sobre la biología y fisiologia de las paralarvas a través de un enfoque multidisciplinarque incluye aspectos innovadores relacionados con la fisiologia de la nutrición y el estrés. Los objetivos propuestos están basados en un fuerte input zootécnico y prevén el uso de herramientas biométricas, bioquímicas, enzimáticas, moleculares y proteómicas, con el fin último de optimizar la condición y supervivencia de las paralarvas. Incluyen asimismo la búsqueda y selección de biomarcadores capaces de detectar y cuantíñcar el estrés nutricional.The culture oflhe common octopus (Octopus vulgaris) is hindered by high mortalities encountered during its paralarval rearing, allhough at present, Ihe specific causes forlhe high mortalities observed remain unidentified. This project aims at galhering a beller understanding of Ihe basic biology and physiology ofthe paralarvae, through a multidisciplinary and integrated approach, which includes Ihe study oflhe physiology 01 nutrition and!he evaluation 01Ihe stress condition. The objectives proposed are basad on a strong zootechnical input and foresee Ihe use of biometric, biochemical, enzymatic, molecular biology and proteomic tools, pointing towards the ultimate optimisation of Ihe paralarval condition and survival. They also include Ihe study ofthe nutritionally-derived stress and Ihe selection ofbiomarkers capable of its detection and quantification