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871.
The feed efficiency and selected organ weights of rats fed diets containing 3 or 7% corn fiber, extruded corn fiber or silica were compared to rats fed a fiber-free diet. No significant differences were found in feed efficiency, spleen, lung or liver weights for any of the treatments relative to the fiber-free control diet.  相似文献   
872.
Aplysina is the best representative genus of the family Aplysinidae. Halogenated substances are its main class of metabolites. These substances contribute greatly to the chemotaxonomy and characterization of the sponges belonging to this genus. Due to their pharmacological activities, these alkaloids are of special interest. The chemistry of halogenated substances and of the alkaloids has long been extensively studied in terrestrial organisms, while the number of marine organisms studied has just started to increase in the last decades. This review describes 101 halogenated substances from 14 species of Aplysina from different parts of the world. These substances can be divided into the following classes: bromotyramines (A), cavernicolins (B), hydroverongiaquinols (C), bromotyrosineketals (D), bromotyrosine lactone derivatives (E), oxazolidones (F), spiroisoxazolines (G), verongiabenzenoids (H), verongiaquinols (I), and dibromocyclohexadienes (J). A compilation of their (13)C NMR data is also part of the review. For this purpose 138 references were consulted.  相似文献   
873.
Objective  To evaluate the quality of brachial plexus blockade with 0.75% ropivacaine in domestic chickens.
Study design  Prospective experimental trial.
Animals  Six 30-week-old female chickens, weighing 4.5 ± 0.4 kg.
Methods  Six brachial plexus injections were performed after anesthetic induction with isoflurane. After achieving adequate muscle relaxation, the animals were positioned in dorsal recumbency and injected with ropivacaine (1 mL kg−1). The birds recovered and assessments of motor function and response to pinch were scored every 5 minutes for 180 minutes. The scores were from zero (no response) to three (greatest response). The scores over time were analyzed using a Wilcoxon nonparametric test with statistical significance accepted if p  ≤ 0.05.
Results  There was a significant difference ( p  < 0.05) from 15 to 130 minutes and 15 to 120 minutes for motor and sensory blocks, respectively. The onset of both blocks took 15 minutes and the effective periods of sensory and motor anesthesia were 105 and 115 minutes, respectively. Comparison between blocks at different times did not demonstrate significant differences ( p  > 0.05).
Conclusions and clinical relevance  No complications were observed after the technique. Brachial plexus blockade with 0.75% ropivacaine is a simple and effective technique for procedures on the thoracic limb of domestic chickens.  相似文献   
874.
A structure-antifungal activity relationship (SAR) study of 22 related cinnamic acid derivatives was carried out. Attention was focused on the antifungal activities exhibited against Aspergillus flavus, Aspergillus terreus, and Aspergillus niger. (E)-3-(4-methoxy-3-(3-methylbut-2-enyl)phenyl)acrylic acid (16) exhibited antifungal activity against A. niger, comparable to that of miconazole and a significant antifungal effect against A. flavus and A. terreus as well. A structure-activity relationship (SAR) study of related cinnamic acid derivatives has allowed a model to be proposed for the recognition of the minimal structural requirements for the antifungal effect in this series.  相似文献   
875.
Seroprevalence of and risk factors for toxoplasmosis in sheep from different properties in the Jaboticabal microregion, São Paulo State, Brazil were determined. Antibodies to Toxoplasma gondii were found in sera of 52.0% of 488 sheep tested by indirect fluorescent antibody test (IFAT ? 64). T. gondii seropositivity in sheep was significantly associated with gender of the sheep, pasturing system, contact with cats, and the use of mineral supplements and the type of feed.  相似文献   
876.
The marine ornamental fish trade (MOFT) is a worldwide industry that targets a remarkable quantity and diversity of reef fish species and provides an important source of revenue for exporting countries, particularly developing nations in Southeast Asia. Here we provide, for the first time, an economic assessment of the MOFT to the European Union (EU), one of the key players of the marine aquarium trade, along with the USA and Japan. Data from EUROSTAT (the European Statistical System) was analysed for the MOFT between 2000 and 2011. Results show that this industry was not affected by the economic crisis and accounted for a total of 135 million Euros during the study period. Both the UK and Indonesia have been reinforcing their importance as leading importer and exporter countries, respectively. The long‐term temporal pattern of the MOFT by EU and non‐EU countries is described, as well as its diversity and evenness between importing and exporting countries. The present economic assessment also identifies the key players of this industry, and ultimately contributes to management and conservation practices that may enhance the sustainable use of world's coral reefs.  相似文献   
877.
Visceral leishmaniasis (VL) is a growing zoonosis with an increasing number of new cases and a rapid geographical spreading of the disease. In the present study, a canine survey was carried out in the city of Montes Claros (320,000 inhabitants), an endemic area of American visceral leishmaniasis in the state of Minas Gerais, Brazil. A total number of 4795 dogs were examined by serology, which showed a rate of seropositivity of 5%. Isoenzymatic analysis confirmed Leishmania infantum chagasi as the local aetiological agent of CVL. Canine tissues were assayed for the presence of Leishmania parasite DNA using different techniques. The infectivity of asymptomatic, oligosymptomatic and symptomatic seropositive dogs was tested by xenodiagnosis using laboratory reared Lutzomyia longipalpis. Rates of infection of 5.4%, 5.1% and 28.4% were found for the phlebotomine sand flies that fed in asymptomatic, oligosymptomatic and symptomatic dogs, respectively. Our results indicate that, under experimental conditions, symptomatic dogs are about four times more infective to VL vectors than oligosymptomatic or asymptomatic animals. The lower infectivity rates of dogs displaying any of the last two clinical forms of leishmaniasis, however, must be taken into account in the epidemiology of CVL.  相似文献   
878.
The optimum concentration of anaesthetic used to facilitate fish handling can be determined based on induction and recovery time, among other factors. This study aimed to evaluate the effectiveness of the essential oil of Aloysia triphylla (EOAT) as an anaesthetic in the handling of Nile tilapia juveniles. Nile tilapias exemplars were immersed at 0 (control group), 10, 20, 30, 40, 80, 150, 300 and 450 μL L?1 EOAT to evaluate sedation, anaesthesia and recovery time. The stress response was evaluated by the determination of plasma glucose, cortisol, lactate and paraoxonase levels in anaesthetized (300 μL L?1 EOAT) and non‐anaesthetized fish. Fillets from both groups were evaluated for organoleptic characteristics (taste and odour). Concentrations of 80–450 μL L?1 EOAT were effective in inducing anaesthesia. There was a significant reduction in plasma cortisol levels one hour after handling in individuals anaesthetized with 300 μL L?1 EOAT compared to the control group. Tasters did not detect differences in fillet taste and odour between fish exposed and not exposed to EOAT. A concentration of 300 μL L?1 EOAT is recommended for handling Nile tilapia because it presents good anaesthetic induction and recovery times, causes a reduction in plasma cortisol levels one hour after handling and does not affect the taste or odour of the fillets.  相似文献   
879.
Tropical Animal Health and Production - The aim of the present study was to develop and evaluate an equation to predict body weight (BW) using hip width (HW) in Pelibuey ewe lambs and ewes. Five...  相似文献   
880.
Thermal processing often results in disruption of the native conformation of whey proteins, thus affecting functional properties. The aim of this work was to evaluate the effects of moderate electric fields on denaturation kinetics and thermodynamic properties of whey protein dispersions at temperatures ranging from 75 to 90 °C. Application of electric fields led to a lower denaturation of whey proteins, kinetically traduced by lower values of reaction order (n) and rate constant (k) (p < 0.05), when compared to those from conventional heating under equivalent heating rates and holding times. Furthermore, the application of electric fields combined with short come-up times has reduced considerably the denaturation of proteins during early stages of heating (>30% of native soluble protein than conventional heating) and has determined also considerable changes in calculated thermodynamic properties (such as E(a), ΔH(?), ΔS(?)). In general, denaturation reactions during moderate electric fields processing were less dependent on temperature increase.  相似文献   
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