1,113 research outputs found
Influence of Ionophore Supplementation on Growth Performance, Dietary Energetics and Carcass Characteristics in Finishing Cattle during Period of Heat Stress.
Forty-eight crossbred heifers (378.1±18 kg) were used in a 56-d feeding trial (four pens per treatment in a randomised complete block design) to evaluate the influence of ionophore supplementation on growth performance, dietary energetics and carcass characteristics in finishing cattle during a period of heat stress. Heifers were fed a diet based on steam-flaked corn (2.22 Mcal NEm/kg) with and without an ionophore. Treatments were: i) control, no ionophore; ii) 30 mg/kg monensin sodium (RUM30); iii) 20 mg/kg lasalocid sodium (BOV20), and iv) 30 mg/kg lasalocid sodium (BOV30). Both dry matter intake (DMI) and climatic variables were measured daily and the temperature humidity index (THI) was estimated. The maximum THI during the study averaged 93, while the minimum was 70 (THI average = 79.2±2.3). Compared to controls, monensin supplementation did not influence average daily gain, the estimated NE value of the diet, or observed-to-expected DMI, but tended (p = 0.07) to increase (4.8%) gain to feed. Compared to controls, the group fed BOV30 increased (p≤0.03) daily gain (11.8%), gain to feed (8.3%), net energy of the diet (5%), and observed-to-expected DMI (5.2%). Daily weight gain was greater (7.6%, p = 0.05) for heifers fed BOV30 than for heifers fed MON30. Otherwise, differences between the two treatments in DMI, gain to feed, and dietary NE were not statistically significant (p>0.11). Plotting weekly intakes versus THI, observed intake of controls was greater (p<0.05) at THI values ≤77 than ionophore groups. When THI values were greater than 79, DMI of control and MON30 were not different (p = 0.42), although less than that of groups fed lasalocid (p = 0.04). Variation in energy intake was lower (p>0.05) in the ionophores group (CV = 1.7%) than in the control group (CV = 4.5%). Inclusion of ionophores in the diet resulted in relatively minor changes in carcass characteristics. It is concluded that ionophore supplementation did not exacerbate the decline of DM intake in heat-stressed cattle fed a high-energy finishing diet; on the contrary, it stabilised feed intake and favoured feed efficiency. Ionophore supplementation reduced estimated maintenance coefficients around 10% in finishing cattle during a period of heat stress. This effect was greatest for heifers supplemented with 30 mg lasalocid/kg of diet
Effects of Replacing Dry-rolled Corn with Increasing Levels of Corn Dried Distillers Grains with Solubles on Characteristics of Digestion, Microbial Protein Synthesis and Digestible Energy of Diet in Hair Lambs Fed High-concentrate Diets.
Four male lambs (Katahdin; average live weight 25.9±2.9 kg) with "T" type cannulas in the rumen and proximal duodenum were used in a 4×4 Latin square experiment to evaluate the influence of supplemental dry distillers grain with solubles (DDGS) levels (0, 10, 20 and 30%, dry matter basis) in substitution for dry-rolled (DR) corn on characteristics of digestive function and digestible energy (DE) of diet. Treatments did not influence ruminal pH. Substitution of DR corn with DDGS increased ruminal neutral detergent fiber (NDF) digestion (quadratic effect, p<0.01), but decreased ruminal organic matter (OM) digestion (linear effect, p<0.01). Replacing corn with DDGS increased (linear, p≤0.02) duodenal flow of lipids, NDF and feed N. But there were no treatment effects on flow to the small intestine of microbial nitrogen (MN) or microbial N efficiency. The estimated UIP value of DDGS was 44%. Postruminal digestion of OM, starch, lipids and nitrogen (N) were not affected by treatments. Total tract digestion of N increased (linear, p = 0.04) as the DDGS level increased, but DDGS substitution tended to decrease total tract digestion of OM (p = 0.06) and digestion of gross energy (p = 0.08). However, it did not affect the dietary digestible energy (DE, MJ/kg), reflecting the greater gross energy content of DDGS versus DR corn in the replacements. The comparative DE value of DDGS may be considered similar to the DE value of the DR corn it replaced up to 30% in the finishing diets fed to lambs
Effects of Combining Feed Grade Urea and a Slow-release Urea Product on Performance, Dietary Energetics and Carcass Characteristics of Feedlot Lambs Fed Finishing Diets with Different Starch to Acid Detergent Fiber Ratios.
Recent findings have shown that microbial nitrogen flow and digestible energy of diets are increased when urea is combined with a slow-release urea (SRU) in diets with a starch to acid detergent fibre ratio (S:F) 4:1. This affect is attributable to enhanced synchrony between ruminal N availability for microbial growth and carbohydrate degradation. To verify the magnitude of this effects on lamb performance, an experiment was conducted to evaluate the effects of combining urea and a SRU in diets containing S:F ratios of 3:1, 4:1, or 5:1 on performance, dietary energetics and carcass characteristics of finishing lambs. For that, 40 Pelibuey×Katahdin lambs (36.65±3 kg) were assigned to one of five weight groupings in 20 pens (5 repetition/treatments). The S:F ratio in the diet was manipulated by partially replacing the corn grain and dried distiller's grain with solubles by forage (wheat straw) and soybean meal to reach S:F ratios of 3:1, 4:1 or 5:1. An additional treatment of 4:1 S:F ratio with 0.8% urea as the sole source of non-protein nitrogen was used as a reference for comparing the effect of urea combination vs. conventional urea at the same S:F ratio. There were no treatment effects on dry matter intake (DMI). Compared the urea combination vs urea at the same S:F ratio, urea combination increased (p<0.01) average daily gain (ADG, 18.3%), gain for feed (G:F, 9.5%), and apparent energy retention per unit DMI (8.2%). Irrespective of the S:F ratio, the urea combination improved the observed-to-expected dietary ratio and apparent retention per unit DMI was maximal (quadratic effect, p≤0.03) at an S:F ratio of 4:1, while the conventional urea treatment did not modify the observed-to-expected net energy ratio nor the apparent retention per unit DMI at 4:1 S:F ratio. Urea combination group tended (3.8%, p = 0.08) to have heavier carcasses with no effects on the rest of carcass characteristics. As S:F ratio increased, ADG, G:F, dietary net energy, carcass weight, dressing percentage and longissimus thoracis (LM) area increased linearly (p≤0.02). Combining urea and a slow-release urea product results in positive effects on growth performance and dietary energetics, but the best responses are apparently observed when there is a certain proportion (S:F ratio = 4:1) of starch to acid detergent fibre in the diet
Compilation and R-matrix analysis of Big Bang nuclear reaction rates
We use the R-matrix theory to fit low-energy data on nuclear reactions
involved in Big Bang nucleosynthesis. A special attention is paid to the rate
uncertainties which are evaluated on statistical grounds. We provide S factors
and reaction rates in tabular and graphical formats.Comment: 40 pages, accepted for publication at ADNDT, web site at
http://pntpm3.ulb.ac.be/bigban
Physicochemical characterization and fatty acid content of ‘venadillo’ (Swietenia humilis Zucc.) seed oil
Physicochemical properties of Swietenia humilis Zucc seed oils were determined along with its fatty acid composition, by using gas-liquid chromatography. The oil content found in the germ portion of the seeds was 45.38%. From physicochemical oil evaluations, an oil density of 0.9099 mg∙ml-1 at 28°C; a refraction index of 1.4740 at 20°C; a saponification index of 159.55 mg KOH∙g-1; a peroxide index of 0.739 meq O2∙kg-1, and 0.367% free fatty acid content were shown. From chromatographic oil evaluations, eight fatty acids were identified showing palmitic (C16:0), stearic (C18:0), oleic (C18:1 cis-9), linoleic (C18:2 cis-9,12), and linolenic (C18:3 cis-9,12,15) as the most predominant. The percentage of saturated, monounsatured and polyunsatured fatty acids were at 18.45, 29.27 and 47.50%, respectively. These results show that ‘venadillo’ oil has a high content of essential fatty acids, mainly linoleic and linolenic. Therefore, this oil shows promissory uses as nutritional component to reduce the cholesterol and triglyceride levels in blood, mostly from patients with higher cardiovascular disease risks.Key words: Oil, α-linolenic acid, linoleic acid, oilseeds, Swietenia humilis
The Merger Rates and Mass Assembly Histories of Dark Matter Haloes in the Two Millennium Simulations
We construct merger trees of dark matter haloes and quantify their merger
rates and mass growth rates using the joint dataset from the Millennium and
Millennium-II simulations. The finer resolution of the Millennium-II Simulation
has allowed us to extend our earlier analysis of halo merger statistics to an
unprecedentedly wide range of descendant halo mass (10^10 < M0 < 10^15 Msun),
progenitor mass ratio (10^-5 < xi < 1), and redshift (0 < z < 15). We update
our earlier fitting form for the mean merger rate per halo as a function of
M_0, xi, and z. The overall behavior of this quantity is unchanged: the rate
per unit redshift is nearly independent of z out to z~15; the dependence on
halo mass is weak (M0^0.13); and it is nearly a power law in the progenitor
mass ratio (xi^-2). We also present a simple and accurate fitting formula for
the mean mass growth rate of haloes as a function of mass and redshift. This
mean rate is 46 Msun/yr for 10^12 Msun haloes at z=0, and it increases with
mass as M^{1.1} and with redshift as (1+z)^2.5 (for z > 1). When the fit for
the mean mass growth rate is integrated over a halo's history, we find
excellent match to the mean mass assembly histories of the simulated haloes. By
combining merger rates and mass assembly histories, we present results for the
number of mergers over a halo's history and the statistics of the redshift of
the last major merger.Comment: 12 pages, 9 figures, accepted in MNRA
Impact on the non-state sector community. Nirvana restaurant case study
El posicionamiento que ha ido adquiriendo en los últimos años el sector no estatal en la capital, con énfasis en la actividad gastronómica, tanto en la estructura de la competencia como en su capacidad generadora de valor, justifica la realización de la presente investigación, que tiene como objetivo, valorar el impacto del restaurante “Nirvana” en la comunidad, para lo cual se empleó un cuestionario en forma de encuesta elaborada a los fines del presente estudio y validada por el coeficiente Alfa de Crombach. La cantidad de encuestados se definió a partir del total de núcleos familiares que habitan en las cuadras más cercanas al restaurante, empleando para ello el programa Sample size carculator. Los resultados se procesaron a través de la estadística paramétrica, el análisis factorial y la prueba de contingencias de Chi cuadrado, empleando el programa SPSS versión 22. Se constató que el restaurante impacta positivamente en la comunidad, básicamente por su contribución a la actividad económica, variable altamente correlacionada con la generación de empleo, condiciones de vida e ingresos personales de los pobladores: De igual modo se observó que la percepción del impacto del restaurante por los encuestados presenta diferencia significativa (p<0,05), siendo valorada de mejor manera por los nacidos en la localidad, los que residen en esta por un mayor periodo de tiempo, los adultos mayores de 60 años, las femeninas y los que habitan más próximo a esta.The position that the non-state sector has acquired in recent years in the capital, with an emphasis on gastronomic activity, both in the structure of competition and in its capacity to generate value, justifies the conduct of this research, which has as objective, to assess the impact of the restaurant "Nirvana" in the community, for which a questionnaire was used in the form of a survey prepared for the purposes of this study and validated by the Alpha coefficient of Crombach. The number of respondents was defined based on the total number of families that live in the blocks closest to the restaurant, using the sample carculator program. The results were processed through parametric statistics, factor analysis and the Chi square contingency test, using the SPSS version 22 program. It was found that the restaurant positively impacts the community, basically due to its contribution to economic activity, variable highly correlated with the generation of employment, living conditions and personal income of the inhabitants: Similarly, it was observed that the perception of the impact of the restaurant by the respondents shows a significant difference (p <0.05), being better valued for those born in the locality, those who reside in it for a longer period of time, adults over 60 years of age, women and those who live closer to it
Immunoliposome-mediated drug delivery to Plasmodium-infected and non-infected red blood cells as a dual therapeutic/prophylactic antimalarial stragegy
One of the most important factors behind resistance evolution in malaria is the failure to deliver sufficiently high amounts of drugs to early stages of Plasmodium-infected red blood cells (pRBCs). Despite having been considered for decades as a promising approach, the delivery of antimalarials encapsulated in immunoliposomes targeted to pRBCs has not progressed towards clinical applications, whereas in vitro assays rarely reach drug efficacy improvements above 10-fold. Here we show that encapsulation efficiencies reaching N96% are achieved for the weak basic drugs chloroquine (CQ) and primaquine using the pH gradient loading method in liposomes containing neutral saturated phospholipids. Targeting antibodies are best conjugated through their primary amino groups, adjusting chemical crosslinker concentration to retain significant antigen recognition. Antigens from non-parasitized RBCs have also been considered as targets for the delivery to the cell of drugs not affecting the erythrocytic metabolism. Using this strategy, we have achieved unprecedented complete nanocarrier targeting to early intraerythrocytic stages of the malaria parasite for which there is a lack of specific extracellular molecular tags. Immunoliposomes studded with monoclonal antibodies raised against the erythrocyte surface protein glycophorin A were capable of targeting 100% RBCs and pRBCs at the low concentration of 0.5 μM total lipid in the culture, with N95% of added liposomes retained on cell surfaces. When exposed for only 15 min to Plasmodium falciparum in vitro cultures of early stages, free CQ had no significant effect on the viability of the parasite up to 200 nM, whereas immunoliposomal 50 nM CQ completely arrested its growth. In vivo assays in mice showed that immunoliposomes cleared the pathogen below detectable levels at a CQ dose of 0.5 mg/kg, whereas free CQ administered at 1.75 mg/kgwas, atmost, 40-fold less efficient. Our data suggest that this significant improvement is in part due to a prophylactic effect of CQ found by the pathogen in its host cell right at the very moment of invasion
Integument Mycobiota of Wild European Hedgehogs (Erinaceus europaeus) from Catalonia, Spain
There are some reports about the risk of manipulating wild hedgehogs since they can be reservoirs of potential zoonotic agents like dermatophytes. The aim of this study was to describe the integument mycobiota, with special attention to dermatophytes of wild European hedgehogs. Samples from spines and fur were cultured separately in Sabouraud dextrose agar (SDA) with antibiotic and dermatophyte test medium (DTM) plates. Nineteen different fungal genera were isolated from 91 cultures of 102 hedgehogs. The most prevalent genera were Cladosporium (79.1%), Penicillium (74.7%), Alternaria (64.8%), and Rhizopus (63.7%). A lower prevalence of Aspergillus (P = 0,035; χ 2 = 8,633) and Arthrinium (P = 0,043; χ 2 = 8,173) was isolated during the spring time and higher frequencies of Fusarium (P = 0,015; χ 2 = 10,533) during the autumn. The prevalence of Acremonium was significantly higher in young animals (70%, 26/37) than in adults (30%, 11/37) (P = 0,019; χ 2 = 5,915). Moreover, the majority of the saprophytic species that grew at the SDA culture were also detected at the DTM. Finally, no cases of ringworm were diagnosed and no dermatophytes spp. were isolated. Concluding, this study provides the first description of fungal mycobiota of the integument of wild European hedgehogs in Spain, showing a large number of saprophytic species and the absence of dermatophytes
Silica nanostructures against fungal growth : design and preparation of antifungal cotton fabrics
Altres ajuts: acord transformatiu CRUE-CSICThe preparation of antifungal-functionalized silica nanoparticles by covalent attachment of several silylated derivatives based on the topical antifungal agent Micozanole is described. Grafting and co-condensation procedures are used to obtain mesoporous or dense nanoparticles. Cotton fabrics have been coated with these antifungal-functionalized silica nanoparticles under ultrasonic conditions. The characterization of the functionalized nanoparticles and coated cotton fabrics is performed by microscopic and spectroscopic techniques. The antifungal activity of all the modified cotton textiles is tested against Trichophyton mentagrophytes CECT 2783, Aspergillus brasiliensis CECT 2091, Penicillium chrysogenum CECT 2307 and Candida albicans CECT 1001, resulting to be highly dependent on the microorganism. Remarkably, all of the modified fabrics are active against Candida albicans and Trichophyton mentagrophytes, with up to 75 and 90% effectiveness, respectively. High expectations arise for topical cutaneous applications in wound dressings (bandages, gauzes, strips)
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