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11.
Studies investigating improved protein:lipid ratios based on their effects on growth, nutrient utilization, digestive enzyme activities, blood metabolites and erythogram in tropical carnivorous fish are very scarce. This study evaluated the effect of different protein:lipid ratios on these parameters in the hybrid surubim Pseudoplatystoma corruscans × Leiarius marmoratus. Juvenile fish (8.90 ± 0.94 g initial weight) were fed 3% of total biomass for 60 days using four isoenergetic experimental diets with different protein:lipid ratios (9.00, 4.60, 3.54 and 1.78). Higher growth performance parameters were observed at higher protein:lipid ratios. The activities of intestine total alkaline protease, trypsin and lipase (U/mg protein) were not affected by dietary treatments. Chymotrypsin (U/mg protein) was higher in the 4.60 protein:lipid ratio group. Amylase (U/mg protein) was higher in intermediate groups. Blood glucose, total plasma protein, triglycerides, cholesterol and free amino acids decreased as the protein:lipid ratio decreased. Haematocrit was higher at the 9.00 and 4.60 protein:lipid ratios. Hybrid surubim showed metabolic adaptation to the different protein:lipid ratios tested. These results suggest that the 4.60 protein:lipid ratio showed the best protein‐sparing effect of lipids.  相似文献   
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The dieback and wilting caused by Erwinia psidii are emerging eucalypt diseases that have been observed since 2014 in the south and central‐south regions of Brazil. Field observations have shown variability in disease severity resistance among Eucalyptus spp. clones and species. It is hypothesized that this variability is due to genetic resistance. To confirm this hypothesis, inoculations in genetically distinct eucalypt plants are necessary. However, lack of an inoculation method and disease assessment makes difficult to select resistant genotypes for use in commercial plantations or genetic breeding programmes. Three inoculation methods were tested on eight clones of Eucalyptus spp. Among them, inoculum deposition with bacteria‐impregnated toothpick on the axillary buds was the simplest and most effective, capable to reproduce the disease symptoms observed under conditions of natural infection. We also developed a rating scale for disease assessment. Among eight clones tested, only Clone 1 (Eucalyptus saligna) and Clone 2 (Eucalyptus urophylla) were resistant.  相似文献   
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We compared the effects of medium light roast (MLR) and medium roast (MR) paper-filtered coffee on antioxidant capacity and lipid peroxidation in healthy volunteers. In a randomized crossover study, 20 volunteers consumed 482?±?61?ml/day of MLR or MR for four weeks. Plasma total antioxidant status (TAS), oxygen radical absorbance capacity (ORAC), oxidized LDL and 8-epi-prostaglandin F2α, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity were measured at baseline and after the interventions. MLR had higher chlorogenic acids-(CGA; 334?mg/150?mL) and less caffeine (231?mg/150?ml) than MR had (210 and 244?mg/150?ml, respectively). MLR also had fewer Maillard reaction products (MRP) than MR had. Compared with baseline, subjects had an increase of 21 and 26?% in TAS, 13 and 13?% in CAT, 52 and 75?% in SOD, and 62 and 49?% in GPx after MLR and MR consumption (P?相似文献   
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Genotoxic and antigenotoxic effects of acerola fruit at two stages of ripeness were investigated using mice blood cells. The results show that no ripeness stage of acerola extracts presented any genotoxic potential to damage DNA (Comet assay) or cytotoxicity (MTT assay). When antigenotoxic activity was analyzed, unripe fruit presented higher DNA protection than ripe fruit (red color) extract. The antioxidant capacity of substances also showed that unripe samples inhibit the free radical DPPH more significantly than the ripe ones. The results about determination of compounds made using HPLC showed that unripe acerola presents higher levels of vitamin C as compared to ripe acerola. Thus, vitamin C and the complex mixture of nutrients of Malpighia glabra L., and especially its ripeness stages, influenced the interaction of the fruit extract with the DNA. Acerola is usually consumed when ripe (red fruit), although it is the green fruit (unripe) that has higher potential as beneficial to DNA, protecting it against oxidative stress.  相似文献   
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Journal of Plant Diseases and Protection - This study aimed to investigate the effects of the essential oils of Cymbopogon flexuosus and Alpinia zerumbet in the treatment of cowpea [Vigna...  相似文献   
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Gaseous effluent from the treatment of contaminated soils must becontrolled to avoid atmospheric emissions of volatile organiccompounds during remediation. The combination of carbonadsorption with catalytic deep oxidation for control ofcyclohexane emissions is analysed in this paper. The activitiesof activated carbons prepared with almond shells and impregnatedwith CoO, Co3O4 and CrO3 were compared, inrelation with carbon structure, catalyst content and catalystspecies. The microcatalytic-chromatographic technique developedwas very suitable for rapid comparison of the catalyticactivities. Carbons with a better development of surface areaand pore volumes showed higher catalytic activities. Theincreasing of catalyst content also increased catalyticactivity. Cobalt is better than chromium to catalyse the deepoxidation of cyclohexane, the oxidation state of cobalt inCo3O4 being better than in CoO.  相似文献   
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Tropical Animal Health and Production - The objective of this study was to evaluate the inclusion of increasing levels of licuri meal as a substitute for soybean bran in the diet of pasture-based...  相似文献   
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The objective of the present study was to investigate the impact of considering population structure in cow genotyping strategies over the accuracy and bias of genomic predictions. A small dairy cattle population was simulated to address these objectives. Based on four main traditional designs (random, top‐yield, extreme‐yield and top‐accuracy cows), different numbers (1,000; 2,000 and 5,000) of cows were sampled and included in the reference population. Traditional designs were replicated considering or not population structure and compared among and with a reference population containing only bulls. The inclusion of cows increased accuracy in all scenarios compared with using only bulls. Scenarios accounting for population structure when choosing cows to the reference population slightly outperformed their traditional versions by yielding higher accuracy and lower bias in genomic predictions. Building a cow‐based reference population from groups of related individuals considering the frequency of individuals from those same groups in the validation population yielded promising results with applications on selection for expensive‐ or difficult‐to‐measure traits. Methods here presented may be easily implemented in both new or already established breeding programs, as they improved prediction and reduced bias in genomic evaluations while demanding no additional costs.  相似文献   
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