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91.
The aim of the present study was to evaluate the potential effects of olive leaf (Olea europea L.) extract (OLE) on common carp (Cyprinus carpio) health in response to ambient ammonia toxicity. Fish were fed with experimental diets containing OLE (0, 1, 5 and 10 g/kg) for 60 days followed by a 3‐hr challenge with ammonia (0.5 mg/L unionized ammonia‐N). Results showed that haemoglobin levels, differential leucocyte counts and mean corpuscular haemoglobin concentration were not affected by dietary OLE levels and ammonia challenge. Ammonia challenge significantly increased red blood cells and decreased blood mean corpuscular volume, mean corpuscular haemoglobin, plasma lysozyme, complement and bactericidal activities. Plasma lysozyme, complement and total immunoglobulin values improved by 5 and/or 10 g OLE/kg supplementation. Before the ammonia exposure, the 5 and 10 g OLE/kg treatment significantly increased blood white blood cell, but there was no significant difference among the treatments after the ammonia exposure. Ammonia exposure significantly increased plasma malondialdehyde levels; however, 1 and 5 g OLE/kg treatments had significantly lower values compared to the other treatments. The present results suggest that 1 g OLE/kg diet may improve fish health and reduce the adverse effects of ammonia toxicity on common carp.  相似文献   
92.
An 8‐week study was applied to evaluate the effects of feed restriction and starvation on growth, proximate composition, haematological and biochemical factors in juvenile Siberian sturgeon Acipenser baerii with an average weight of 54 ± 0.6 g. Fish were randomly divided into nine indoor tanks (1,050 L volume) with 30 fish per tank in a flow‐through system at 18 ± 0.4°C. Three feeding strategies were considered: I) fed at satiation (F), II) restricted feeding at the rate of 1% body weight per day (R) and III) starvation (S) each with 3 replicates. Fish were fed with commercial pellets 4 times daily, but no feed was considered for S group throughout the trial. Basal level at the start, 4 and 8 weeks after initiation of the experiment, blood samples were taken from 5 fish/tank to measure the haematological and biochemical parameters. Moreover, growth performance was recorded every 2‐week interval. At the end of the experiment, the growth parameters and proximate composition were significantly different among the treatments. As expected, the highest weight (164.7 ± 2.1 g) was observed in F group compared to R (101 ± 1.7 g), or S (42.4 ± 0.8 g) groups. The highest (12.07 ± 0.14%) and lowest (5.37 ± 0.42%) fat contents were observed in F and S groups, respectively, while the protein was not affected in R group compared with F group. In addition, most haematological and biochemical indices of Siberian sturgeon were affected by starvation at week 4 and 8, while few changes were observed in restricted feeding. The highest mean corpuscular volume, mean corpuscular haemoglobin, plasma total protein, cholesterol and triglyceride was found in S group, while the lowest value of plasma glucose was observed in this group. It can be concluded that Siberian sturgeon adjusts the physiological condition in short‐term (4 weeks) feed restriction using stored metabolites to have basal metabolism and due to this, a short period of feed restriction strategy recommends to the optimum nutritional management of Siberian sturgeon to cost‐saving during unsuitable conditions.  相似文献   
93.
94.
The ethanolic extracts of Curcuma longa and Alpinia galanga exhibited excellent (100%) phytotoxic activity against Lemma minor. These extracts were also found to possess good antifungal activities against Trichophyton longifusus (65% and 60%, respectively), while in the brine shrimp lethality bioassay were found to be toxic with LD50 of 33 and 109 mincrog/ml, respectively. These extracts were found quite inert in antibacterial bioassay, while the extract from C. longa, tested for insecticidal activity, was also found to be devoid of any activity.  相似文献   
95.
Heaves is a common condition of horses of cold climate that is characterized by small airway inflammation and obstruction following exposure of susceptible horses to moldy hay and straw. It has been shown that helper T lymphocytes (Th) orchestrate the inflammatory response in asthma and in various animal models of allergic lung diseases by the release of Th2-type cytokines. Results of previous studies indicate that a predominant expression of Th2-type response by airway cells may also be present in heaves. To evaluate the temporal mRNA expression of Th1 (IFN-gamma) and Th2 (IL-4, IL-5) type cytokines in heaves and their relationship to clinical disease, we studied the pulmonary mechanics and cytokine mRNA expression (IL-4, IL-5 and IFN-gamma) in bronchoalveolar lavage lymphocytes of horses with heaves (n=6) and control (n=6) before and after 24h and 9 days of continuous natural inhalation challenge. Starting 24h after challenge horses with heaves, but not control horses, had a significant increase in pulmonary elastance and the number of lymphocytes expressing mRNA for IL-4 and IL-5. These changes were further increased at 9 days, at which time the number of cells positive for IFN-gamma mRNA was decreased. In this study we have shown that BAL lymphocytes of horses with heaves during clinical exacerbation have a predominant Th2-type cytokine response and that this response coincides in time with the presence of airway obstruction.  相似文献   
96.
Fifteen of 100 mastitic milk samples from goats suffering from mastitis were tentatively identified as members of the genus Nocardia on the basis of selected phenotypic and chemotaxonomic characteristics. Six of the 155 strains were confirmed as Nocardia farcinica by 16S rDNA gene sequencing and subsequent aligning with relevant actinomycetes found in electronic databases and 2 by other identification criteria. N. farcinica is a serious cause of mastitis with a significant prevalence (15%) among the examined goats. Efforts are needed to optimise and simplify isolation and identification methods.  相似文献   
97.
When chickpea shoots were placed in solanapyrone A, the compound could not be recovered from the plant and symptoms developed. These consisted of loss of turgor, shrivelling and breakage of stems and flame-shaped, chlorotic zones in leaflets. In similar experiments with solanapyrone B, only 9.4% (22 μ g) of the compound taken up was recovered and stems remained turgid but their leaflets became twisted and chlorotic and some abscized.Cells isolated from leaflets of 12 chickpea cultivars differed by up to five-fold in their sensitivity to solanapyrone A and this compound was 2.6–12.6 times more toxic than solanapyrone B, depending on cultivar.Glutathione reacted with solanapyrone A in vitro reducing its toxicity in a cell assay and forming a conjugate. Measurement of reduced glutathione concentration and glutathione-S-transferase (GST) activity among cultivars showed that the differences of their means were highly significant and both were negatively and significantly correlated with their sensitivity to solanapyrone A. Treatment of shoots with solanapyrone A enhanced total, reduced and oxidized glutathione content as well as GST activity 1.26-, 1.23-, 1.50- and 1.94-fold, respectively. Similarly, treatment of shoots with the safener, dichlormid, also raised total, oxidized and reduced glutathione levels and GST activity 1.42-, 1.07-, 1.43-, 1.42-fold, respectively. Cells isolated from shoots treated with dichlormid at 150 and 300 μ g per shoot were 2.45 and 2.66 times less sensitive to solanapyrone A, with LD50values of 71.5 and 77.8 μ g ml−1, respectively, as compared to 29.2 μ g ml−1for controls.  相似文献   
98.
Vegetative propagation techniques such as grafting can be used, in conjunction with field studies, to decouple the relative effects of age and size on tree metabolism and growth. Despite interest in this approach, little attention has been paid to the best metrics for assessing the growth performance of grafted plants over time. Based on an analysis of the grafting literature and our own data, we show that the choice of metrics to assess tree growth can entirely change the conclusions reached about the relative importance of age versus size. We recommend that absolute as well as relative rates of growth are calculated and that scion size be standardized as much as possible at the start of the experiment. Once proper metrics are chosen, all of the available published evidence is largely concordant with two concepts: (1) age-mediated controls of tree growth are likely to be important during the first few years of a tree's life (before phase change); and (2) after the first few years of a tree's life, size-mediated factors largely prevail over age-mediated factors in determining tree growth rates. We found no support for theories invoking age-mediated sink limitations in old trees.  相似文献   
99.
<正>Erratum to:Journal of Forestry Reasearch,(2013)24(3):611-614DOI10.1007/s11676-013-0393-2The original version of this article unfortunately contained one mistake in author name in the footnote.The second author's name,"Mousa Rasouli",actually should be Hamid Soofi Mariv.The corrected version of the footnote should be as the following:  相似文献   
100.
Using spectral reflectance to estimate crop status is a method suitable for developing sensors for site-specific agricultural applications. When developing spectral analysis methods, it is important to know the influence of different crop parameters on the spectral reflectance profile. The objective of this report was to present and evaluate a multivariate method for objective hyperspectral analysis in the examination of how different parts of the reflectance spectrum are affected by disease severity and above ground plant density. Data from two field experiments were used; fungal disease severity assessments in wheat 1998 and above ground plant density measurements 2003. The analysis method consisted of two steps: a pre-processing step where the data was normalized and a classification step for estimating the crop variable. Using only 12% of the data as training data, the method resulted in coefficients of determination (R 2) of 94.3% for the disease severity data and 96.9% for the plant density data. The hyperspectral analysis method presented could also be used to extract spectral signatures of disease severity and plant density using the experimental data. In general, two types of spectral signatures for both data sets, with respect to increasing disease severity and decreasing plant density, were observed (1) a flattening of the green reflectance peak together with a general decrease in reflectance in the near infrared region and, (2) a decrease of the shoulder of the near infrared reflectance plateau together with a general increase in the visible region between 550 and 750 nm.  相似文献   
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