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101.
Rita C. Coelho Miguel A. Faria Joana Rocha Aida Reis Maria Beatriz P.P. Oliveira Eugénia Nunes 《Scientia Horticulturae》2009
The common bean (Phaseolus vulgaris L.) is the most consumed legume in the world. In Portugal, the geographic isolation of the region surrounded by the mountainous barrier of Peneda-Gerês, Barroso and Marão is thought to have the safeguard of a large number of adapted bean populations. In order to assess the value of this germplasm to breeding programs, a study of 20 Portuguese landraces collected in this Northern region were evaluated for agronomical (days to flowering, plant height, days to harvest, weight of seeds per plant and 100 seeds weight), chemical (crude protein) and genetic diversity (microsatellite DNA). 相似文献
102.
Astaxanthin krill oil enhances the growth performance and fatty acid composition of the Pacific whiteleg shrimp,Litopenaeus vannamei,reared under hypersaline conditions
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Hypersalinity culture of marine shrimp can lead to poor growth and feed efficiency. This study evaluated the effect of dietary supplementation of three oil sources (krill, fish and soybean) on the growth of Litopenaeus vannamei reared under high salinity. Shrimp of 2.79 ± 0.60 g were reared for 64 days under isosmotic (ISO, 23 ± 1.2 g/L) and hyperosmotic (HOS, 44 ± 2.0 g/L) conditions. Diets varied in their fatty acid composition: Control, 35 g/kg of the diet (as fed basis) soybean oil; Fish, 27 g/kg fish oil and 10 g/kg soybean oil; Krill, 48 g/kg krill oil and 4 g/kg soybean oil; Krill‐, 15 g/kg krill oil and 21 g/kg soybean oil; Krill+, 55 g/kg krill oil and 4 g/kg soybean oil. At harvest, Krill diet promoted the fastest shrimp growth (1.01 ± 0.01 g/week) and body weight (11.97 ± 2.01 g), regardless of water salinity. There were no significant differences in shrimp survival (93.4 ± 5.07%) and yield (554 ± 68.5 g/m2) among different diets. Shrimp fed Fish, Krill and Krill+ had higher concentrations of PUFA compared to those fed Control and Krill‐ diets. 相似文献
103.
To study the mechanism of coffee melanoidin formation, green coffee beans were prepared by (1) removal of the hot water extractable components (WECoffee); (2) direct incorporation of sucrose (SucCoffee); and (3) direct incorporation of type II arabinogalactan-proteins (AGPCoffee). As a control of sucrose and AGP incorporation, lyophilized green coffee beans were also immersed in water (control). The original coffee and the four modified "in bean" coffee models were roasted and their chemical characteristics compared. The formation of material not identified as carbohydrates or protein, usually referred to as "unknown material" and related to melanoidins, and the development of the brown color during coffee roasting have distinct origins. Therefore, a new parameter for coffee melanoidin evaluation, named the "melanoidin browning index" (MBI), was introduced to handle simultaneously the two concepts. Sucrose is important for the formation of colored structures but not to the formation of "unknown material". Type II AGPs also increase the brown color of the melanoidins, but did not increase the amount of "unknown material". The green coffee hot water extractable components are essential for coffee melanoidin formation during roasting. The cell wall material was able to generate a large amount of "unknown material". The galactomannans modified by the roasting and the melanoidin populations enriched in galactomannans accounted for 47% of the high molecular weight brown color material, showing that these polysaccharides are very relevant for coffee melanoidin formation. 相似文献
104.
Senegalese sole (Solea senegalensis) is a high-value commercial species with increasing importance in aquaculture. The aim of this work was to study the quality changes of this species during chilled storage under refrigeration, through sensory and chemical methods. In particular, the optimization of a quality index method (QIM) scheme was proposed as well as the definition of sensory and chemical quality criteria. A shelf life of 15 days was reported, and a QIM scheme based on a total of 22 demerit points (dp) was proposed. Biogenic amines were never detected, and the usual spoilage indicators, such as TVB-N and TMA-N, were not significantly produced during the period of sensory-acceptable quality (15 days). On the basis of the significant correlations (p<0.001) between sensory data and Ki values, a quality index (QI) 19 dp and a Ki>40% indicate unacceptable quality of iced Senegalese sole. 相似文献
105.
Paulo S.P. Santos DVM MS James N.B.M. Andrade DVM MS ré L. Selmi DVM MS Jorge L.O. Costa DVM MS Rafael R. Faleiros DVM MS Newton Nunes DVM MS PhD 《Journal of Veterinary Emergency and Critical Care》2003,13(1):7-12
Objective: To determine the cardiovascular effects of desflurane in dogs following acute hemorrhage. Design: Experimental study. Animals: Eight mix breed dogs. Interventions: Hemorrhage was induced by withdrawal of blood until mean arterial pressure (MAP) dropped to 60 mmHg in conscious dogs. Blood pressure was maintained at 60 mmHg for 1 hour by further removal or replacement of blood. Desflurane was delivered by facemask until endotracheal intubation could be performed and a desflurane expiratory end‐tidal concentration of 10.5 V% was maintained. Measurements and main results: Systolic, diastolic, and mean arterial blood pressure (SAP, DAP and MAP), central venous pressure (CVP), cardiac output (CO), stroke volume (SV), cardiac index (CI), systemic vascular resistance (SVR), heart rate (HR), respiratory rate (RR), partial pressure of carbon dioxide in arterial blood (PaCO2), and arterial pH were recorded before and 60 minutes after hemorrhage, and 5, 15, 30, 45 and 60 minutes after intubation. Sixty minutes after hemorrhage, SAP, DAP, MAP, CVP, CO, CI, SV, PaCO2, and arterial pH decreased, and HR and RR increased when compared with baselines values. Immediately after intubation, MAP and arterial pH decreased, and PaCO2 increased. Fifteen minutes after intubation SAP, DAP, MAP, arterial pH, and SVR decreased. At 30 and 45 minutes, MAP and DAP remained decreased and PaCO2 increased, compared with values measured after hemorrhage. Arterial pH increased after 30 minutes of desflurane administration compared with values measured 5 minutes after intubation. Conclusions: Desflurane induced significant changes in blood pressure and arterial pH when administered to dogs following acute hemorrhage. 相似文献
106.
The addition of organic acids to diet of young pigs has been shown to improve their zootechnical performance. The aim of these experiments was to evaluate the effects of dietary supplementation with BA (VevoVitall®) on the zootechnical performance (DWG and FCR), the gastrointestinal microflora of the weaner piglet and to determine the effects on the ileal digestibility. For the zootechnical and microbiological evaluations 124 28-day-old piglets were used. During 32 days half of them were fed a maize–soybean meal based diet and the other half this diet supplemented with 0.5% BA. At the end of the study the stomach and caecum contents were sampled from 12 animals of each group for microbiological determinations. For the ileal digestibility study 60-day-old ileo-rectal anastomosed piglets were used and fed alternatively the same diet supplemented or not with 0.5% BA. Digestibilities of total nitrogen (N), energy (E) and amino acids (AA) were evaluated.
The BA group had significantly higher DWG and FCR than that of the control group. BA reduced almost all the determined bacterial populations of the gastrointestinal tract of the piglet. The reductions were significant for gastric lactic acid bacteria and caecal E. coli. The ileal digestibility of E and AA was numerically improved and that of N significantly increased in the BA group. 相似文献
107.
Phosphorus (P) from plant-derived feedstuffs is mainly in the form of phytic-P, which has a very low bioavailability in monogastric animals. The non-absorbed phytic-P may contribute to P pollution, reduce mineral bioavailability and might reduce protein digestibility. The aim of this study was to evaluate the effects of the recommended levels of Ronozyme® P CT 5000 (750 U/kg — RP) and Natuphos® 5000 (500 U/kg — Nat) on the ileal apparent digestibility of total P, phytates (Phy), calcium (Ca), total nitrogen (N), energy, and amino acids (AA) in 60-day-old ileo-rectal anastomosed pigs. In a double Latin square design they were fed ad libitum either a maize–rapeseed meal based diet or this diet supplemented with RP or with Nat. RP and Nat increased the digestibility of P by 148% and 162%, of Phy by 84% and 76%, and of Ca by 44% and 50%, respectively. The total N digestibility was increased by 4% with RP (P < 0.01) and by 1% with Nat. A numerically increase of the digestibility of most of the AA was observed for Nat and of all AA for RP. Threonine digestibility was significantly increased by RP (P < 0.05). The results of this study indicate that phytases are able to increase the availability of proteins. 相似文献
108.
Water-use strategies in two co-occurring Mediterranean evergreen oaks: surviving the summer drought 总被引:1,自引:0,他引:1
David TS Henriques MO Kurz-Besson C Nunes J Valente F Vaz M Pereira JS Siegwolf R Chaves MM Gazarini LC David JS 《Tree physiology》2007,27(6):793-803
In the Mediterranean evergreen oak woodlands of southern Portugal, the main tree species are Quercus ilex ssp. rotundifolia Lam. (holm oak) and Quercus suber L. (cork oak). We studied a savannah-type woodland where these species coexist, with the aim of better understanding the mechanisms of tree adaptation to seasonal drought. In both species, seasonal variations in transpiration and predawn leaf water potential showed a maximum in spring followed by a decline through the rainless summer and a recovery with autumn rainfall. Although the observed decrease in predawn leaf water potential in summer indicates soil water depletion, trees maintained transpiration rates above 0.7 mm day(-1) during the summer drought. By that time, more than 70% of the transpired water was being taken from groundwater sources. The daily fluctuations in soil water content suggest that some root uptake of groundwater was mediated through the upper soil layers by hydraulic lift. During the dry season, Q. ilex maintained higher predawn leaf water potentials, canopy conductances and transpiration rates than Q. suber. The higher water status of Q. ilex was likely associated with their deeper root systems compared with Q. suber. Whole-tree hydraulic conductance and minimum midday leaf water potential were lower in Q. ilex, indicating that Q. ilex was more tolerant to drought than Q. suber. Overall, Q. ilex seemed to have more effective drought avoidance and drought tolerance mechanisms than Q. suber. 相似文献
109.
Aggressiveness,cultural characteristics and genetic variation of Ceratocystis fimbriata on Eucalyptus spp.
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L. S. S. Oliveira L. M. S. Guimarães M. A. Ferreira A. S. Nunes L. V. A. Pimenta A. C. Alfenas 《Forest Pathology》2015,45(6):505-514
Ceratocystis wilt caused by Ceratocystis fimbriata is currently one of the most important diseases affecting Eucalyptus in Brazil. This disease is controlled by planting resistant clones; however, possible variability in the pathogen population may compromise the selection of resistant genotypes. Therefore, this study aimed to evaluate the aggressiveness of C. fimbriata isolates obtained from Eucalyptus spp, as well as their cultural characteristics and genetic variation of their ITS rDNA gene region. We found a significant isolate × clone interaction, with the isolate RM35 being the most aggressive and presenting a broader spectrum of aggressiveness, causing greater xylem discoloration on a larger number of clones. This isolate is the most suitable for artificial inoculations focusing on the selection of resistant materials. Clones CLR‐236 and CLR‐212 were identified as the most resistant and clones CLR‐223 and CLR‐240 as the most susceptible and those that are recommended as reliable comparators in artificial inoculations. All isolates were morphologically similar and differed from C. fimbriata from sweet potato by the formation of a wide mouth endoconidiophore that produces doliform endoconidia. According to the culture media and temperature applied, the most favourable conditions for mycelial growth were observed using malt extract agar (MEA) and temperatures ranging from 24 to 26°C. There was no correlation between sporulation and aggressiveness. Great variation in ITS sequences was observed, and a total of five ITS genotypes were identified among the ten isolates tested. 相似文献