73,034 research outputs found

    WELFARE, PRODUCTIVITY AND QUALITATIVE TRAITS OF EGG IN LAYING HENS REARED UNDER DIFFERENT REARING SYSTEMS

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    The welfare, production performance and some qualitative characteristics of eggs obtained under three different rearing systems (conventional, organic and organic-plus) were compared. Three homogeneous groups, each of 120 White Leghorn hens, fed the same diets, were assigned to different rearing systems and data were recorded for 1 year. The welfare indicators were the following: first impact, behavioural patterns, tonic immobility and plumage status. Productive performance was recorded (% deposition; egg weight) and some qualitative traits (Haugh index, yolk colour, yolk, albumen and egg shell weight) were evaluated. Well-being was greatly affected by rearing system. The best welfare status was observed in hens of the organic-plus group, whereas the worst was in the conventional group (caged hens). Caged hens showed little interest or fear of observers, at times they had high tonic immobility and some aggressive pecking; the status of their plumage was very poor. On the contrary, caged hens produced more eggs, even if their qualitative traits (Haugh index and yolk colour) were worse than the organicplus eggs. The intense motor activity of organic hens and the concurrent intake of grass reduced their productive level; further egg deposition seemed more affected by seasonal variation

    COMPARISON OF TWO CHICKEN GENOTYPES ORGANICALLY REARED: OXIDATIVE STABILITY AND OTHER QUALITATIVE TRAITS

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    The effect of genotype on the oxidative stability and other qualitative traits of chicken meat was studied. Two groups of 200 chicks (Ross 205 and Kabir) were reared according to the organic farming system. At 81 d of age 20 birds per group were slaughtered and after refrigeration (24 h at 4°C) of the carcasses, Pectoralis major muscles were excised for analyses.Samples were analysed after 0, 24, 48, 72 and 96 hours of storage at 4°C under continuous fluorescent illumination (2300 lux). The analyses concerned the chemical composition and the shear force (only at time 0) and the progress of several traits as pH, CIELAB values, Thiobarbituric Acid Reactive Substances (TBARS), panel test and fatty acid composition (at 0 and after 96 h). Genotype greatly affected the physico-chemical characteristics and the sensory evaluation. The meat from Ross chickens showed high TBARS values, perhaps due to selection for growth rate that reduced their adaptability to greater space allowance and to poorer environmental conditions; these higher TBARS values were also negatively correlated to lightness and yellowness. The initial level of TBARS affected the oxidative stability of breast meat during storage. The amount of TBARS showed significantly negative relationship with the sensory evaluation; breast meat of Kabir had higher scores for liking when the level of malondialdehyde was less than 2.5 mg kg-1

    SUSTAINABILITY OF POULTRY PRODUCTION USING THE EMERGY APPROACH: COMPARISON OF CONVENTIONAL AND ORGANIC REARING SYSTEMS

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    The organic production system is an important strategy, compatible with sustainable agriculture, avoiding the use of chemical compounds,limiting the intensity of production and providing controls along the entire chain of production. The aim of this study is to compare conventional and organic poultry production in terms of emergy analysis. The main differences in the two systems were the emergy cost for poultry feed and for cleaning/sanitization of the buildings between successive productive cycles. In both production systems the poultry feed represented more than 50% of the emergy flow. Regarding the agronomic phase, it was shown that almost all the organic crops, avoiding chemical fertilizers and pesticides, saved around 60% emergy. The emergetic costs for housing of the birds were very similar in both systems. Relating the emergy results with productive performance it is possible to show that, although the annual productive performance was much lower in organic than in conventional (206%), transformity of organic poultry was around 10% lower. Comparison of the organic poultry system with a conventional one from the viewpoint of sustainability showed that all the emergy-based indicators are in favour of the organic farming system with a higher efficiency in transforming the available inputs in the final product, a higher level of renewable inputs, a higher level of local inputs and a lower density of energy and matter flows

    MEAT QUALITY OF THREE CHICKEN GENOTYPES REARED ACCORDING TO THE ORGANIC SYSTEM

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    The meat quality of three poultry genotypes with differing growth rates (fast-growing Ross; medium and slow growing Kabir and Robusta maculata, respectively) was compared. All the birds were reared according to the organic production system which requires a paddock with grass pasture (4 m2/bird) and a slaughter age greater than 81 d. The trial was carried out on 100 female chickens per strain. The meat quality was affected by the 20 different degree of maturity of the strains at slaughter age, which was 70% for Ross, 52 % for Kabir and 78% for Robusta maculata. Ross and Kabir were slaughtered at 81 d, whereas Robusta maculata, required 120 d to reach a commercial weight (>2 kg). The meat of all the three genotypes showed good qualitative traits. The main differences of the three genotypes regarded moisture, lipid, pHu, colour, iron, oxidative stability and overall acceptance. Compared with Kabir and Robusta maculata Ross meat had more fat, lower pHu and iron, and was 25 paler. The oxidative stability during display (24-96 h at 4° C) and acceptance were the worst. Kabir chickens, being the least mature strain, had the highest moisture content with a high cooking loss. The slower-growing genotypes showed a good adaptation to the extensive rearing conditions, while the fast-growing genotype showed unbalanced muscle response to the greater activity and the oxidative stability of the meat was reduced

    Interpolatory Weighted-H2 Model Reduction

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    This paper introduces an interpolation framework for the weighted-H2 model reduction problem. We obtain a new representation of the weighted-H2 norm of SISO systems that provides new interpolatory first order necessary conditions for an optimal reduced-order model. The H2 norm representation also provides an error expression that motivates a new weighted-H2 model reduction algorithm. Several numerical examples illustrate the effectiveness of the proposed approach

    Emissions of Volatile Organic Compounds Inferred From Airborne Flux Measurements over a Megacity

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    Toluene and benzene are used for assessing the ability to measure disjunct eddy covariance (DEC) fluxes of Volatile Organic Compounds (VOC) using Proton Transfer Reaction Mass Spectrometry (PTR-MS) on aircraft. Statistically significant correlation between vertical wind speed and mixing ratios suggests that airborne VOC eddy covariance (EC) flux measurements using PTR-MS are feasible. City-median midday toluene and benzene fluxes are calculated to be on the order of 14.1±4.0 mg/m<sup>2</sup>/h and 4.7±2.3 mg/m<sup>2</sup>/h, respectively. For comparison the adjusted CAM2004 emission inventory estimates toluene fluxes of 10 mg/m<sup>2</sup>/h along the footprint of the flight-track. Wavelet analysis of instantaneous toluene and benzene measurements during city overpasses is tested as a tool to assess surface emission heterogeneity. High toluene to benzene flux ratios above an industrial district (e.g. 10–15 g/g) including the International airport (e.g. 3–5 g/g) and a mean flux (concentration) ratio of 3.2±0.5 g/g (3.9±0.3 g/g) across Mexico City indicate that evaporative fuel and industrial emissions play an important role for the prevalence of aromatic compounds. Based on a tracer model, which was constrained by BTEX (BTEX– Benzene/Toluene/Ethylbenzene/m, p, o-Xylenes) compound concentration ratios, the fuel marker methyl-tertiary-butyl-ether (MTBE) and the biomass burning marker acetonitrile (CH<sub>3</sub>CN), we show that a combination of industrial, evaporative fuel, and exhaust emissions account for >87% of all BTEX sources. Our observations suggest that biomass burning emissions play a minor role for the abundance of BTEX compounds in the MCMA (2–13%)

    The Preservation of Cued Recall in the Acute Mentally Fatigued State: A Randomised Crossover Study.

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    The objective of this study is to investigate the impact of acute mental fatigue on the recall of clinical information in the non-sleep-deprived state. Acute mental fatigue in the non-sleep-deprived subject is rarely studied in the medical workforce. Patient handover has been highlighted as an area of high risk especially in fatigued subjects. This study evaluates the deterioration in recall of clinical information over 2 h with cognitively demanding work in non-sleep-deprived subjects.A randomised crossover study involving twenty medical students assessed free (presentation) and cued (MCQ) recall of clinical case histories at 0 and 2 h under low and high cognitive load using the N-Back task. Acute mental fatigue was assessed through the Visual Analogue Scale, Stanford Scale and NASA-TLX Mental Workload Rating Scale.Free recall is significantly impaired by increased cognitive load (p < 0.05) with subjects demonstrating perceived mental fatigue during the high cognitive load assessment. There was no significant difference in the amount of information retrieved by cued recall under high and low cognitive load conditions (p = 1).This study demonstrates the loss of clinical information over a short time period involving a mentally fatiguing, high cognitive load task. Free recall for the handover of clinical information is unreliable. Memory cues maintain recall of clinical information. This study provides evidence towards the requirement for standardisation of a structured patient handover. The use of memory cues (involving recognition memory and cued recall methodology) would be beneficial in a handover checklist to aid recall of clinical information and supports evidence for their adoption into clinical practice

    ASPETTI COMPORTAMENTALI, PRESTAZIONI PRODUTTIVE E QUALITÀ DELL'UOVO IN GALLINE ALLEVATE CON IL METODO BIOLOGICO

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    The aim of this trial was to study the effect of organic housing system on the behaviour, productive performance and the qualitative characteristics of eggs. The experiment was conduced directly in the field on Hy-Line laying hens from the beginning of the productive period (17 weeks of age) till the end of productive career. The animals were divided in two homogeneous groups and assigned to the following housing system: control, conventional cage (18 bird/m2) and organic 6 birds m2 in a covered straw-bedded house with access to a paddock (4 m2/bird). A standard feed with the same nutritive characteristics was given ad libitum to the chickens. For the organic, more than 80% of the ingredients (maize, wheat and whole soybean) were organically grown, as established by Regulation 1804/99. Ethological parameters (first impact, tonic immobility and behavioural patterns) and the plumage conditions showed better welfare conditions in organic laying hens. The greater movement of those animals lowered productive performances (lighter and less eggs); on the contrary the higher welfare and the minor overexploitation of organic animals permitted a longer productive life. The microbiological safety of eggs showed low levels of mesophila bacteria even though the organic system increased their mean value. There were few enterobacteria (< 100 CFU) and Salmonella spp. not present in any of the eggs analysed

    Research Performance of Engineering Colleges in Karnataka as reflected in the Scopus Database

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    This paper intends to assess the growth of research publications and citations of engineering colleges affiliated to Visvesvaraya Technological University (VTU), Belagavi based on Scopus database. It is attempted to analyze parameters like the growth of research output among rural and city colleges i.e. geographical distribution of publications, pattern of research communication, share of national and international collaboration across Karnataka and high productivity institutions and top highly published journals and cited papers
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