Effect of the dietary supplementation with sunflower oil and incremental levels of marine algae on the rumen bacterial community in dairy sheep

1 page.-- Contributed to: 7th Rowett-INRA Symposium. Gut microbiology: new insight into gut microbial ecosystems (Aberdeen, Reino Unido, Jun 23-25, 2010).In lactating ruminants, the dietary supplementation with lipids rich in linoleic acid, such as sunflower oil (SO), and long-chain polyunsaturated fatty acids (PUFA)...Peer reviewe

Isolation of RNA from milk somatic cells as an alternative to biopsies of mammary tissue for nutrigenomic studies in dairy ewes

11 páginas, 4 tablas, 1 figura.Nutrigenomic studies of mammary lipogenesis in ruminants often rely on the use of mammary tissue (MT) collected either by biopsy or at slaughter. However, isolating RNA from milk would be a useful and cost-effective technique that may avoid distress to the animal and facilitate the collection of samples in time series experiments. This assay was therefore conducted to test the hypothesis that RNA extracted from milk somatic cells (MSC) in dairy sheep would be a feasible alternative to the performance of MT biopsies for nutrigenomic analyses. To meet this objective, 8 lactating Assaf ewes were divided in 2 groups and offered a total mixed ration without supplementation (control) or supplemented with 2.4% dry matter of fish oil, which was known not only to elicit milk fat depression but also to downregulate the expression of some candidate genes involved in mammary lipogenesis. Total RNA was extracted from MSC and biopsied MT to examine whether the potential changes in the abundance of transcripts was similarly detected with both RNA sources. Milk fatty acid profile was also analyzed by gas chromatography, and variations in mRNA abundance were determined by reverse transcription quantitative PCR. Values of RNA integrity number were always ≥7.7. The expected and designed decrease of milk fat concentration with fish oil (−29%), was associated with a lower transcript abundance of genes coding for enzymes involved in fatty acid activation (ACSS1), de novo synthesis (ACACA and FASN), uptake from plasma lipids (LPL), and esterification of fatty acids to glycerol (LPIN1), as well as of a transcription factor that may regulate their expression (INSIG1). Stable mRNA levels were showed in other candidate genes, such as FABP3, GPAT4, or SCD. Changes due to the dietary treatment were similarly detected with both RNA sources (MSC and MT biopsies), which supports the initial hypothesis and would validate the use of milk as an alternative RNA source for nutrigenomic analyses in dairy sheep.This work was supported by the Ministry of Economy and Competitiveness (MINECO, Spain; AGL2014-54587, co-funded by the European Regional Development Fund, European Union). P. G. Toral gratefully acknowledges receipt of a postdoctoral research contract from the MINECO (Juan de la Cierva program).Peer reviewe

Comparison of ruminal lipid metabolism in dairy cows and goats fed diets supplemented with starch, plant oil or fish oil

16 páginas, 5 tablas, 1 figura.Direct comparison of cow and goat performanceand milk fatty acid responses to diets known to inducemilk fat depression (MFD) in the bovine revealsrelevant species-by-diet interactions in ruminal lipidmetabolism. Thus, this study was conducted to inferpotential mechanisms responsible for differences in therumen microbial biohydrogenation (BH) due to dietand ruminant species. To meet this objective, 12 cowsand 15 goats were fed a basal diet (control), a similardiet supplemented with 2.2% fish oil (FO), or a dietcontaining 5.3% sunflower oil and additional starch(+38%; SOS) according to a 3 × 3 Latin square designwith 25-d experimental periods. On the last day of eachperiod, fatty acid composition (by gas chromatography)and bacterial community (by terminal-RFLP),as well as fermentation characteristics, were measuredin rumen fluid samples. Results showed significant differencesin the response of cows and goats to dietarytreatments, although variations in some fermentationparameters (e.g., decreases in the acetate-to-propionateratio due to FO or SOS) were similar in both species.Main alterations in ruminal BH pathways potentiallyresponsible for MFD on the SOS diet (i.e., the shiftfrom trans-11 to trans-10 18:1 and related increases intrans-10,cis-12 18:2) tended to be more pronounced incows, which is consistent with an associated MFD onlyin this species. However, changes linked to FO-inducedMFD (e.g., decreases in 18:0 and increases in totaltrans-18:1) were stronger in caprine rumen fluid, whichmay explain their unexpected susceptibility (althoughless marked than in bovine) to the negative effect ofFO on milk fat content. Altogether, these results suggestthat distinct ruminal mechanisms lead to eachtype of diet-induced MFD and confirm a pronouncedinteraction with species. With regard to microbiota,differences between cows and goats in the compositionof the rumen bacterial community might be behindthe disparity in the microorganisms affected by theexperimental diets (e.g., Ruminococcaceae, Lachnospiraceae,and Succinivibrionaceae in the bovine, andPseudobutryrivibrio, Clostridium cluster IV, Prevotella,and Veillonellaceae in the caprine), which hinderedthe assignation of bacterial populations to particularBH steps or pathways. Furthermore, most relevantvariations in microbial groups corresponded to as yetuncultured bacteria and suggest that these microorganismsmay play a predominant role in the ruminal lipidmetabolism in both cows and goats.This study was supported by INRA (UMR1213; France) and the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2014-54587). P. G. Toral was granted a postdoctoral fellowship from Fundación Alfonso Martín Escudero (Madrid, Spain) and a research contract from the MINECO (Juan de la Cierva program).Peer reviewe

Elucidating fish oil-induced milk fat depression in dairy sheep: Milk somatic cell transcriptome analysis

9 páginas, 4 figuras.In this study, RNA sequencing was used to obtain a comprehensive profile of the transcriptomic changes occurring in the mammary gland of lactating sheep suffering from fish oil-induced milk fat depression (FO-MFD). The milk somatic cell transcriptome analysis of four control and four FO-MFD ewes generated an average of 42 million paired-end reads per sample. In both conditions, less than 220 genes constitute approximately 89% of the total counts. These genes, which are considered as core genes, were mainly involved in cytoplasmic ribosomal proteins and electron transport chain pathways. In total, 117 genes were upregulated, and 96 genes were downregulated in FO-MFD samples. Functional analysis of the latter indicated a downregulation of genes involved in the SREBP signaling pathway (e.g., ACACA, ACSL, and ACSS) and Gene Ontology terms related to lipid metabolism and lipid biosynthetic processes. Integrated interpretation of upregulated genes indicated enrichment in genes encoding plasma membrane proteins and proteins regulating protein kinase activity. Overall, our results indicate that FO-MFD is associated with the downregulation of key genes involved in the mammary lipogenesis process. In addition, the results also suggest that this syndrome may be related to upregulation of other genes implicated in signal transduction and codification of transcription factors.This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2014-54587-R and AGL2015-66035-R projects, co-funded by the European Regional Development Fund). P.G.T. and B.G.G. are funded by two postdoctoral research contracts from MINECO (Juan de la Cierva -JCI-2012-11836- and Ramón y Cajal -RYC-2012-10230 programs, respectively).Peer reviewe

Effects of a tannin-rich legume (Onobrychis viciifolia) on in vitro ruminal biohydrogenation and fermentation

There is still controversy surrounding the ability of tannins to modulate the ruminal biohydrogenation (BH) of fatty acids (FA) and improve the lipid profile of milk or meat without conferring a negative response in the digestive utilization of the diet. Based on this, an in vitro trial using batch cultures of rumen microorganisms was performed to compare the effects of two legume hays with similar chemical composition but different tannin content, alfalfa and sainfoin (Onobrychis viciifolia), on the BH of dietary unsaturated FA and on the ruminal fermentation. The first incubation substrate, alfalfa, was practically free of tannins, while the second, sainfoin, contained 3.5% (expressed as tannic acid equivalents). Both hays were enriched with sunflower oil as a source of unsaturated FA. Most results of the lipid composition analysis (e.g., greater concentrations of 18:2n-6, cis-9 18:1 or total polyunsaturated FA in sainfoin incubations) showed the ability of this tannin-containing legume to inhibit the BH process. However, no significant differences were detected in the accumulation of cis-9 trans-11 conjugated linoleic acid, and variations in trans-11 18:1 and trans-11 cis-15 18:2 did not follow a regular pattern. Regarding the rumen fermentation, gas production, ammonia concentration and volatile FA production were lower in the incubations with sainfoin (‒17, ‒23 and ‒11%, respectively). Thus, although this legume was able to modify the ruminal BH, which might result in improvements in the meat or milk lipid profile, the present results were not as promising as expected or as obtained before with other nutritional strategies

Leguminosas bioactivas para mejorar el perfil lipídico de la carne de cordero

6 páginas, 2 figuras, 1 tabla.La utilización de leguminosas forrajeras en la dieta de los rumiantes puede ofrecer importantes ventajas. Además de su elevado valor proteico, algunas especies como la esparceta o el trébol rojo, contienen compuestos bioactivos que podrían mejorar la calidad nutricional de la carne. Entre ellos, destacan los taninos en la esparceta y la polifenol oxidasa en el trébol rojo. Ahora bien, la climatología de muchas áreas limita su aprovechamiento en verde. En este estudio, mostramos que la utilización de la esparceta y el trébol rojo conservados mediante ensilado podría ser una buena alternativa para la alimentación de corderos, al aumentar la concentración de ácidos grasos poliinsaturados (PUFA) en la carne a través de su efecto sobre el metabolismo lipídico ruminal. Aunque el mecanismo de acción de los compuestos bioactivos presentes en estos forrajes probablemente sea distinto, sus efectos sobre el perfil de ácidos grasos de la carne parecen ser similares y aditivos.Este trabajo forma parte del proyecto Legume Plus, financiado por la Comisión Europea a través de una Red de Formación Inicial Marie Curie (PITN GA- 2011- 289377) PG . Toral disfruta de un contrato Ramón y Cajal, financiado por el Ministerio de Economía, lndustria y Competitividad.Peer reviewe

La microbiota ruminal como fuente de enzimas industriales

Resumen el español e inglésTítulo en inglés: Ruminal microbiota as a source of industrial enzymesEl rumen constituye una gran cámara de fermentación colonizada por una compleja comunidad microbiana que está compuesta mayoritariamente por especies que no pueden cultivarse. Por ello, la microbiota ruminal representa una fuente inexplorada de enzimas para la industria biotecnológica. La diversidad funcional de estos microorganismos tiene un alto potencial para el desarrollo de aplicaciones industriales más sostenibles y eficientes (p. ej., para la producción de biodiesel, la degradación de sustancias plásticas o la fabricación de ingredientes de origen biológico). Nuestros equipos de investigación están trabajando con contenido digestivo del rumen de ovejas. Mediante un cribado de alta capacidad, buscamos nuevas enzimas relacionadas con el metabolismo lipídico (hidratasas y deshidrogenasas). Entre sus posibles aplicaciones estaría la de contribuir a la biotransformación; por ejemplo, convirtiendo los ácidos grasos de diversos residuos, como los aceites usados de fritura, en productos con mayor valor añadido (hidroxi- y cetoácidos)The rumen is a large fermentation chamber colonised by a complex mi crobial community that is mostly composed of as-yet uncultured species. Therefore, rumen microbiota represents an unexplored source of enzymes for the biotechnology industry. The functional diversity of these microor ganisms has high potential for the development of more sustainable and efficient industrial applications (e.g., for the production of biodiesel, the degradation of plastic substances or the manufacture of bio-based ingre dients). Our research teams are working with rumen digesta of sheep. We use high throughput screening to search for new enzymes related to lipid metabolism (hydratases and dehydrogenases). Potential applications in clude contribution to biotransformation, for example, by converting fatty acids from various waste products, such as used frying oils, into higher value-added products (hydroxy- and keto-acids

Effects of different forage: concentrate ratios in dairy ewe diets supplemented with sunflower oil on animal performance and milk fatty acid profile

1 página.-- Trabajo presentado al: IDF International Symposium on Sheep, Goat and other non-Cow Milk (Atenas, Grecia, del 16 al 18 de mayo de 2011).The aim of this study was to evaluate the effect of different forage: concentrate (FC) ratios in dairy ewe diets supplemented with sunflower oil (SO) on animal performance and milk fatty acid (FA) profile, particularly focusing on trans C18:1 FAs and conjugated linoleic acid (CLA). For that purpose, sixty lactating Assaf ewes were randomly assigned to 6 treatments in a 3 x 2 factorial arrangement: 3 FC ratios (30:70, 50:50 and 70:30) and 2 levels of SO addition (0 and 20 g/kg DM). Both the diet FC ratio and SO supplementation affected milk yield, although differences between treatments were fairly small. Although the proportion of concentrate induced limited changes in milk FA profile, dietary SO significantly reduced saturated FAs and enhanced total CLA. Furthermore, the incorporation of SO in ewe diets decreased the atherogenicity index value by about 25% and doubled potentially healthy FA contents such as trans-11 C18:1 and cis-9 trans-11 CLA. However, the inclusion of SO in a high concentrate diet (30:70) could switch linoleic acid biohydrogenation pathways, resulting in a significant increase in trans-10 C18:1, trans-9 cis-11 C18:2 and trans-10 cis-12 C18:2 milk fat percentages.Peer reviewe

Zientzia eskola egutegia 2021 (EUS)

El proyecto “Calendario Científico Escolar 2021” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales.Proyecto FECYT - FTC-2019-15288Peer reviewe

(árabe - العربية‎) 2024 الرزنامة الدراسية العلمية

El proyecto “Calendario Científico Escolar 2024” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales. Se trata de la cuarta edición de este proyecto de divulgación científica.El proyecto “Calendario Científico Escolar 2024” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales. Se trata de la cuarta edición de este proyecto de divulgación científica.Instituto Geológico y Minero de España (IGME); Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA); Centro de Biología Molecular Severo Ochoa (CBMSO); Instituto Español de Oceanografía (IEO); Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA); Museo Nacional de Ciencias Naturales (MNCN); Centre d'Estudis Avançats de Blanes (CEAB); Institut d’Investigació en Intel.ligéncia Artificial (IIIA); Institut de Microelectrònica de Barcelona - Centre Nacional de Microelectrònica (IMB-CNM); Institut de Ciències del Mar (ICM, CSIC). Discapacitodos; Mujeres con Ciencia; Comisión Mujeres y Ciencia de la Sociedad Geológica de España; Asociación Española para el Avance de la Ciencia (AEAC); PRISMA – Asociación para la diversidad afectivo-sexual y de género en ciencia, tecnología e innovación; Círculo Escéptico; Universitat de les Illes Balears (UIB); Asociaţia Secular-Umanistă din România; Civiencia; Universidad Autónoma de Madrid; Evento Ciencia; Europa Laica; Canaima; Universitat Autònoma de Barcelona; Fundación Odón de BuenPeer reviewe