2,420 research outputs found

    La adición de enzimas a dietas basadas en maíz y harina de soya y el desempeño productivo y la composición de la canal de guineas (Numida me/eagris) de engorde.

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    Recent studies have demonstrated the benefits of supplementation of broiler chick diets based on corn and soybean meal with enzymes such as amylases and proteases. However, these benefits cannot necessarily be extrapolated to the commercial production of other species of domestic animals. The objective of this study was to determine the effects of diet fortification with Avizyme® (AV) on guinea broiler growth performance and processing yields. Six hundred guinea keets, randomly assigned to four treatments with 10 replications of 15 birds per pen, were reared under a three-phase feeding regime until market age (84 d) in a conventional poultry house. Treatments consisted of diets containing 0 (control), 0.025,0.050, and 0.075% of AV. Birds and feed were weighed weekly until 84 d of age to determine body weight (BW), feed intake (Fl), and feed conversion ratio (FCR). Dead and culled birds (CB) were remo ved and weighed daily. At 84 d, 50 birds per treatment were processed to evaluate carcass composition. The weights of carcass (CW), fat pad (FP) and carcass parts were obtained and yields were calculated as a percentage of live BW. No differences in BW, mortality, CB and CW were found among treatments. The yields of car cass, breast, drumsticks, thighs, and FP were similar for all dietary treatments evaluated. Results at 35, 63 and 84 d were mixed, but in general birds fed diets containing AV exhibited lower (P < 0.01) Fl and FCR than control birds. At 84 d, birds fed 0.025% AV diets had lower (P < 0.01) Fl and FCR than controls. These data suggest that supplementation with corn and soybean meal-based diets with at least 0.025% of AV improves FCR of guinea broilers without affecting BW at market age nor carcass composition.Estudios recientes han demostrado los beneficios de la suplementación con enzimas como amilasas y proteasas en dietas para pollos de engorde basadas en maíz y harina de soya. Sin embargo, estos beneficios no necesariamente pueden ser extrapolados a la producción comercial de otras especies de animales domésticos. El objetivo de este estudio fue determinar los efectos de la fortificación dietética con Avizyme® (AV) sobre el crecimiento y rendimiento de procesado de guineas de engorde. Seiscientos pollos de guineas de engorde, asignados al azar a cuatro tratamientos con 10 repeticiones de 15 aves por jaula, se criaron bajo un régimen de alimentación trifásica hasta la edad de mercado (84 d) en un galpón de cría convencional. Los tratamientos consistieron en dietas que contenían 0 (Control), 0.025, 0.050 y 0.075% de AV. Semanalmente se pesó el alimento y las ares, hasta alcanzar los 84 d de edad, para determinar el peso corporal (PC), consumo de alimento (CA) y la razón de conversión de alimento (RCA). Las aves muertas y rezagadas (AR) se remo vieron y se pesar on diariamente. A los 84 d de edad, se procesaron 50 aves por tratamiento para evaluar las características de la canal, obteniéndose los pesos de la canal (PCN),grasa abdominal (GA) y partes de la canal; los rendimientos se calcularon como un porcentaje del peso vivo. No se observaron diferencias entre tratamientos para PC, mortalidad, AR ni PCN. Los rendimientos de canal, pechuga, muslos, caderas y GA fueron similares para todos los tratamientos evaluados. Los resultados para CA a los 35, 63 y 84 d de edad fueron mixtos, pero en general las aves suplementadas con AV exhibieron menor (P < 0.01) CA y RCA que las guineas control. A los 84 d, las aves alimentadas con la adición dietética de 0.025% de AV obtuvieron menores CA y RCA (P < 0.01) que las aves control. Estos datos sugieren que la adición de al menos un 0.025% de AV a dietas a base de soya y maíz mejora la conversión de alimento de gallinas de guinea de engorde sin afectar el PC a la edad de mercado ni la composición de la canal

    Inclusión de un producto fermentado de pescado en la dieta de guineas (Numida meleagris): desempeño productivo y calidad de la carcasa

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    Guinea fowl (Numida meleagris) is a poultry species suitable for use in meat production to expand and diversify the local poultry industry because of its advantages of high consumer acceptance, resistance to common poultry diseases, and tolerance to poor management conditions. However, the poor feed conversion of this species increases feed costs and limits production. To reduce feed costs it is imperative to find locally available feedstuffs of low cost but with adequate nutritional value. The use of a fermented fish by-product meal (FFBPM) as a protein source in guinea diets could satisfy these criteria and reduce feed costs. This study with 180 birds was undertaken to evaluate the effects of the inclusion of a FFBPM in guinea diets on productive performance and carcass quality. Treatments consisted of FFBPM inclusion at levels of 0 (control), 5, and 10% in each of the starter, grower, and finisher diets. Feed and birds were weighed at 0, 35, 63, and 84 d to determine body weight (BW) and feed conversion. At 84 d, half the birds of each treatment were processed for evaluating carcass composition and determining yields of carcass and major cuts. Fasted live body weights, and plucked and dressed carcass weights were recorded and yields calculated. No significant differences in BW were observed among treatments at 0,63, and 84 d. At 35 d, BW was lower (P < 0.05) in birds with a 10% FFBPM inclusion. Feed conversion at 35 d was also higher with 10% FFBPM and lower in control birds, whereas those receiving 5% FFBPM did not differ from those of the other treatments. Birds fed 10% FFBPM showed significantly lower live, plucked, and dressed weights than those of the control and those fed 5% FFBPM. No differences among treatments were observed in yields of dressed carcass, major cuts, and the proportions of flesh, skin, and bone. However, the percentage of abdominal fats was significantly lower in birds fed a 10% FFBPM than in birds of the control and in those fed the 5% FFBPM level. The results of this study indicate that the inclusion of up to 5% FFBPM in guinea diets has no detrimental effect on bird performance and carcass quality. Thus, FFBPM could be a valuable feed ingredient to supply part of the dietary protein requirements of guinea fowl. La crianza de guinea (Numida meleagris) es una alternativa viable para aumentar la producción local de carne de aves debido a su buena aceptación por el consumidor, resistencia a enfermedades y tolerancia a condiciones de manejo adversas. Sin embargo, la pobre conversión alimenticia de estas aves aumenta los costos de alimentación, limitando su producción. Para reducir dichos costos es necesario utilizar ingredientes poco costosos pero de valor nutricional adecuado. La utilización de un subproducto fermentado de pescado (SPFP) como fuente de proteína en dietas de guinea podría satisfacer estos requisitos y reducir los costos de alimentación. El propósito de esta investigación fue evaluar el efecto de la inclusión de SPFP en dietas de guineas sobre el desempeño productivo y la calidad de la carcasa. Los tratamientos consistieron en la inclusión de 0, 5 y 10% SPFP en las dietas de iniciación, crecimiento y terminación. Se pesó el alimento y las aves a los 0, 35, 63 y 84 d para determinar el peso corporal y la conversión alimenticia. A los 84 d, se procesaron 90 aves para evaluar la calidad de la carcasa y determinar el rendimiento de la misma y sus componentes principales. Se midió su peso vivo en ayuno, peso desplumado y peso listo para cocinar y se calcularon los rendimientos. No se observaron diferencias significativas en peso corporal entre los tratamientos a los 0, 63 y 84 d. A los 35 d el peso corporal fue menor (P < 0.05) en aves a las que se les suministró un 10% SPFP. La conversión alimenticia a los 35 d fue mayor en aves a las que se les suministró 10% SPFP y menor en las aves control, mientras la de aquellas a las que se les suministró 5% SPFP fue similar a la del resto de los tratamientos. Las aves con 10% SPFP registraron un peso vivo, desplumado y listo para cocinar más bajo (P < 0.05) que las aves control y aquéllas con 5% SPFP. No se encontraron diferencias en el rendimiento de la carcasa, cortes principales ni en la proporción de carne, hueso y piel. Sin embargo, el porcentaje de grasa abdominal fue menor (P < 0.05) para las aves a las que se les suministró 10% SPFP y mayor en aves del grupo control. Los resultados de este experimento indican que la inclusión de hasta 5% SPFP en la dieta no tiene efectos detrimentales sobre el desempeño productivo y la calidad de carcasa. El SPFP podría ser un recurso alimentario útil para suplir parcialmente los requisitos proteicos de la guinea

    A bio-inspired robust controller for a refinery plant process

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    This research presents a novel bio-inspired knowledge method, based on gain scheduling, for the calculation of Proportional-Integral-Derivative controller parameters that will prevent system instability. The aim is to prevent a transition to control system instability due to undesirable controller parameters that may be introduced manually by an operator. Each significant operation point in the system is identified first. Then, a solid stability structure is calculated, using transfer functions, in order to program a bio-inspired model by using an artificial neural network. The novel method is empirically verified under working conditions in a real refinery plant process

    A Bio-inspired knowledge system for improving combined cycle plant control tuning

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    This study presents a novel bio-inspired knowledge system, based on closed loop tuning, for calculating the Proportional-Integral-Derivative (PID) controller parameters of a real combined cycle plant. The aim is to automatically achieve the best parameters according to the work point and the dynamics of the plant. To this end, several typical expressions and systems were taken into account to build the model for this multidisciplinary study. Each of these expressions is appropriated for a particular system. The novel method is empirically verified under a real case study based on an auxiliary steam system of a combined cycle plant

    Preparation and Study of the Antibacterial Applications and Oxidative Stress Induction of Copper Maleamate-Functionalized Mesoporous Silica Nanoparticles

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    Mesoporous silica nanoparticles (MSNs) are an interesting class of nanomaterials with potential applications in different therapeutic areas and that have been extensively used as drug carriers in different fields of medicine. The present work is focused on the synthesis of MSNs containing a maleamato ligand (MSN-maleamic) and the subsequent coordination of copper(II) ions (MSN-maleamic-Cu) for the exploration of their potential application as antibacterial agents. The Cu-containing nanomaterials have been characterized by different techniques and the preliminary antibacterial effect of the supported maleamato-copper(II) complexes has been tested against two types of bacteria (Gram positive and Gram negative) in different assays to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The biological results showed a moderate antibacterial activity against Escherichia coli which motivated a more detailed study of the antibacterial mechanism of action of the synthesized maleamate-containing nanosystems and whose findings showed oxidative stress generation in bacterial cells. All the prepared nanomaterials were also tested as catalysts in the “solvent free” selective oxidation of benzyl alcohol, to observe if there is a potential correlation between the catalytic oxidation capacity of the materials and the observed oxidative stress in bacteria. This may help in the future, for a more accurate rational design of antibacterial nanosystems, based on their observed catalytic oxidation activity.This research was funded by Ministerio de Ciencia, Innovación y Universidades Spain-FEDER, grants number CTQ2015-66164-R and CTQ2017-90802-REDT and by Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT) (PICT 2015 Nº1558)

    Evaluation of the potential of total proanthocyanidin content in feces as an intake biomarker.

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    Due to the health benefits associated with proanthocyanidins (PAs), it is useful to identify dietary PA biomarkers that can be determined by simple methods. Since increased levels of circulating PA metabolites are associated with increased fecal PA content, this study explores the spectrophotometric measurement of fecal PA content and its use as a biomarker of PA intake. To this end, fecal PA content was measured using an adaptation of Porter’s spectrophotometric method in samples from a preclinical study and an observational study. In the former, excretion of 250–400 mg PA polymer equivalents/100 g feces was observed during supplementation and the day after, together with a significant association (p < 0.05) between PA intake and the excretion of both intact PAs and some PA metabolites, i.e., (+)-catechin, (−)-epicatechin and syringic acid. No relationship between intake and excretion was found in the observational study, either for the entire group (mean excretion of 240 ± 226 mg PA polymer equivalents/100 g feces) or after stratification into tertiles of consumption. In conclusion, the spectrophotometric determination of total PA content in feces proved to be a valid compliance marker in a preclinical study, but it was not associated with PA intake in free-living subjects. The potential of total PA excretion in observational studies, determined in fecal samples collected the day before dietary recall or in several fecal samples from the same subject, remains to be elucidated, as does a complete validation of the method proposed here.post-print552 K

    A Hybrid Regression System Based on Local Models for Solar Energy Prediction

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    The aim of this study is to predict the energy generated by a solar thermal system. To achieve this, a hybrid intelligent system was developed based on local regression models with low complexity and high accuracy. Input data is divided into clusters by using a Self Organization Maps; a local model will then be created for each cluster. Different regression techniques were tested and the best one was chosen. The novel hybrid regression system based on local models is empirically verified with a real dataset obtained by the solar thermal system of a bioclimatic house

    Demersal and epibenthic communities of sedimentary habitats in the Avilés Canyon System, Cantabrian Sea (NE Atlantic)

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    The aim of this study was to describe the epibenthic and demersal communities of the Avilés Canyon System (ACS) in relation to the environmental variables that characterize their biotope. ACS (Cantabrian Sea, NE Atlantic) was recently included in the Natura 2000 network as a Site of Community Importance (SCI). Data of faunal biomass derived from 6 surveys carried out using beam trawl and otter trawls in 2009 and 2010 within INDEMARES and ERDEM projects. Data were divided into two groups to obtain information about the two ecological compartments: benthic and demersal. The total number of species used in this analysis ascended to 116 in the case of benthic organisms and 110 in the case of demersal. Hierarchical clustering analysis was applied to obtain groups of samples similar in terms of species composition for the two ecological components. Depth was the main discriminating factor for grouping hauls, showing high consistency of bathymetric range independently from the compartment examined. Six groups were identified by depth as follows: medium shelf (∼100–200 m), external shelf (∼150–300m), shelf break (∼300–400 m), upper-slope (∼500–700 m), upper middle-slope (∼700–1100 m), and lower-middle-slope (1200–1500 m). SIMPER analysis on biomass values was performed to determine the structure of the faunal assemblages observed for each group in both compartments. Using biomass values for the analysis allowed for the exploration of groups playing important roles in ecosystem functioning and energy fluxes taking place on the sedimentary bottom of this SCI. Finally, CCA analysis revealed that the main environmental drivers were depth, broad scale bathymetric position index (BPI), near-bottom salinity, sedimentary type, and dynamics related variables (Q50 phy and So). This study gives an inventory of the soft bottom assemblages along a very wide depth range (100–1500 m) inside a SCI, linking both epibenthic and demersal communities with the biotope preferences. This study contributes to fundamental knowledge on soft-bottom communities as a pre-requisite, necessary for the next steps in terms of management framework in the SCI

    Interspecific Introgression in Cetaceans: DNA Markers Reveal Post-F1 Status of a Pilot Whale

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    Visual species identification of cetacean strandings is difficult, especially when dead specimens are degraded and/or species are morphologically similar. The two recognised pilot whale species (Globicephala melas and Globicephala macrorhynchus) are sympatric in the North Atlantic Ocean. These species are very similar in external appearance and their morphometric characteristics partially overlap; thus visual identification is not always reliable. Genetic species identification ensures correct identification of specimens. Here we have employed one mitochondrial (D-Loop region) and eight nuclear loci (microsatellites) as genetic markers to identify six stranded pilot whales found in Galicia (Northwest Spain), one of them of ambiguous phenotype. DNA analyses yielded positive amplification of all loci and enabled species identification. Nuclear microsatellite DNA genotypes revealed mixed ancestry for one individual, identified as a post-F1 interspecific hybrid employing two different Bayesian methods. From the mitochondrial sequence the maternal species was Globicephala melas. This is the first hybrid documented between Globicephala melas and G. macrorhynchus, and the first post-F1 hybrid genetically identified between cetaceans, revealing interspecific genetic introgression in marine mammals. We propose to add nuclear loci to genetic databases for cetacean species identification in order to detect hybrid individuals.

    Diagnostic ability of multifocal electroretinogram in early multiple sclerosis using a new signal analysis method

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    Purpose To determine if a novel analysis method will increase the diagnostic value of the multifocal electroretinogram (mfERG) in diagnosing early-stage multiple sclerosis (MS). Methods We studied the mfERG signals of OD (Oculus Dexter) eyes of fifteen patients diagnosed with early-stage MS (in all cases &lt; 12 months) and without a history of optic neuritis (ON) (F: M = 11:4), and those of six controls (F:M = 3:3). We obtained values of amplitude and latency of N1 and P1 waves, and a method to assess normalized root-mean-square error (FNRMSE) between model signals and mfERG recordings was used. Responses of each eye were analysed at a global level, and by rings, quadrants and hemispheres. AUC (area under the ROC curve) is used as discriminant factor. Results The standard method of analysis obtains further discrimination between controls and MS in ring R3 (AUC = 0.82), analysing N1 waves amplitudes. In all of the retina analysis regions, FNRMSE value shows a greater discriminating power than the standard method. The highest AUC value (AUC = 0.91) was in the superior temporal quadrant. Conclusion By analysing mfERG recordings and contrasting them with those of healthy controls it is possible to detect early-stage MS in patients without a previous history of ON
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