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61.
Rabies is a zoonotic, fatal and progressive neurological infection caused by rabies virus of the genus Lyssavirus and family Rhabdoviridae. It affects all warm-blooded animals and the disease is prevalent throughout the world and endemic in many countries except in Islands like Australia and Antarctica. Over 60,000 peoples die every year due to rabies, while approximately 15 million people receive rabies post-exposure prophylaxis (PEP) annually. Bite of rabid animals and saliva of infected host are mainly responsible for transmission and wildlife like raccoons, skunks, bats and foxes are main reservoirs for rabies. The incubation period is highly variable from 2 weeks to 6 years (avg. 2–3 months). Though severe neurologic signs and fatal outcome, neuropathological lesions are relatively mild. Rabies virus exploits various mechanisms to evade the host immune responses. Being a major zoonosis, precise and rapid diagnosis is important for early treatment and effective prevention and control measures. Traditional rapid Seller's staining and histopathological methods are still in use for diagnosis of rabies. Direct immunofluoroscent test (dFAT) is gold standard test and most commonly recommended for diagnosis of rabies in fresh brain tissues of dogs by both OIE and WHO. Mouse inoculation test (MIT) and polymerase chain reaction (PCR) are superior and used for routine diagnosis. Vaccination with live attenuated or inactivated viruses, DNA and recombinant vaccines can be done in endemic areas. This review describes in detail about epidemiology, transmission, pathogenesis, advances in diagnosis, vaccination and therapeutic approaches along with appropriate prevention and control strategies.  相似文献   
62.
The present investigation was carried out in coastal Sundarbans of India to study the effects of farm yard manure, green leaf manure, and vermicompost on biological attributes of soils and yield in rice–tomato, rice–sunflower, and rice–chili cropping system over conventional farmer’s practices (control) by a strip-plot technique for the two consecutive years. The partial substitution of inorganic fertilizers through organics significantly increased the yield of various cropping systems. The use of organic materials significantly improved microbial biomass carbon, fluorescein diacetate hydrolyzing activities, dehydrogenase, and β-glucosidase activity over control, which varied in the tune of 51.6%, 67.4%, 50%, and 62.7%, respectively, due to variation in electrical conductivity (EC) of these soils. The improved soil microbial biomass and enzyme activities act as key driving factor for organic matter decomposition and nutrient transformation in organically amended soils which lead to better yield under such cropping sequences.  相似文献   
63.
Abstract

Critical values of boron (B) for wheat nutrition in soil and plant were determined through a pot experiment with twenty-one surface soils of Alluvial flood plain and Red-latertic belt comprising three major soil orders (Entisols, Alfisols, Inceptisols) with four levels of boron. Application of boron significantly increased the dry matter yield as well as uptake of B by plants. Critical concentration of hot calcium chloride (CaCl2) extractable B in soil for wheat was found to be 0.53?mg?kg?1. The critical plant B concentration varied with growth stages and values were 7.4?mg?kg?1 at panicle initiation and 4.18?mg?kg?1 at maturity, respectively. The findings of this investigation also recommend the application of 2?kg?B?1?ha?1 for ensuring B sufficiency to wheat in Indo-gangetic alluvial and Red-Lateritic soils.  相似文献   
64.
Endotoxin, also referred to as lipopolysaccharide (LPS), can stimulate localized or systemic inflammation via the activation of pattern recognition receptors. Additionally, endotoxin and inflammation can regulate intestinal epithelial function by altering integrity, nutrient transport, and utilization. The gastrointestinal tract is a large reservoir of both gram-positive and gram-negative bacteria, of which the gram-negative bacteria serve as a source of endotoxin. Luminal endotoxin can enter circulation via two routes: 1) nonspecific paracellular transport through epithelial cell tight junctions, and 2) transcellular transport through lipid raft membrane domains involving receptor-mediated endocytosis. Paracellular transport of endotoxin occurs through dissociation of tight junction protein complexes resulting in reduced intestinal barrier integrity, which can be a result of enteric disease, inflammation, or environmental and metabolic stress. Transcellular transport, via specialized membrane regions rich in glycolipids, sphingolipids, cholesterol, and saturated fatty acids, is a result of raft recruitment of endotoxin-related signaling proteins leading to endotoxin signaling and endocytosis. Both transport routes and sensitivity to endotoxin may be altered by diet and environmental and metabolic stresses. Intestinal-derived endotoxin and inflammation result in suppressed appetite, activation of the immune system, and partitioning of energy and nutrients away from growth toward supporting the immune system requirements. In livestock, this leads to the suppression of growth, particularly suppression of lean tissue accretion. In this paper, we summarize the evidence that intestinal transport of endotoxin and the subsequent inflammation leads to decrease in the production performance of agricultural animals and we present an overview of endotoxin detoxification mechanisms in livestock.  相似文献   
65.

Sulfated polysaccharides (SP) from seaweeds exhibit numerous biological activities and are less toxic than conventional antiviral drugs. However, little is known about their mode of action. This study aims at extracting the polysaccharides from brown seaweed Sargassum ilicifolium and then evaluating its antiviral activity against fish Betanodavirus. The extracted SP was characterized through FT-IR, 1H NMR, and thermal gravimetric analysis (TGA). The antiviral activity of SP was tested on SGA cell line by syncytia reduction and the polysaccharide represented a prominent antiviral activity to Betanodavirus by reducing the cytopathic effect (CPE) formation in vitro. The study revealed that SP effectively blocked viral attachment and entry. Moreover, during the in vivo challenge experiment in Gambusia affinis, SP treatment showed a significant decrease in the viral titers. Hence, these results indicate that the polysaccharides obtained from S. ilicifolium exhibited the high antiviral potential to Betanodavirus infection in fishes both in vitro and in vivo.

  相似文献   
66.
Background:Effect of monochromatic green light illumination on embryo development has been reported in chickens. The avian pineal gland is an important photo-en...  相似文献   
67.
In the present study, the extractability of available Boron (B) by different extractants was tested in relation to soil properties. Soil samples from different parts of Indo-Gangetic flood plains of West Bengal were collected and available B extracted with various extractant viz. hot calcium chloride (CaCl2) (HCC), Potassium di-hydrogen phosphate (PDP), tartaric acid (TA) and MCC. Plant availability of B was assessed by growing wheat (Triticum aestivum L.cv.K-1006) in such soils through pot experiments. HCC showed the highest available B content as well as highest correlation coefficient value with all plant growth parameters and soil properties. The B extracting efficiency of the tested extractants was found in the order of HCC > PDP > TA > MCC. Results showed that dry matter yield, plant B concentration and uptake was increased significantly after application of Borax. Linear Correlations, Multiple regression analysis using Mallow's Cp statistics proved HCC to be the best extractant for estimating available B in experimental soils.  相似文献   
68.
69.
A 7‐week study was conducted to investigate the effect of different fasting and re‐feeding regimes on compensatory growth and some physiological parameters of juvenile Siberian sturgeon (Acipenser baerii). Fish (46.5 ± 0.5 g) were fed on a diet (containing 450 g/kg crude protein and 20 MJ/kg digestible energy) according to four feeding regimes in triplicate including: control group (C, fed everyday), W1 (2 weeks of feeding followed by 1 week of fasting and 4 weeks of re‐feeding), W2 (1 week of feeding followed by 2 weeks of fasting and 4 weeks of re‐feeding) and W3 (3 weeks of fasting followed by 4 weeks of re‐feeding). The fasted groups including W1 (119.6 ± 2.1 g), W2 (118.0 ± 1.7 g) and W3 (108.5 ± 4.8) significantly lost their weights during fasting phase and did not attain the final weight of the C (137.3 ± 1.7 g) after re‐feeding phase. The re‐feeding phase increased the specific growth rate in the fasted groups compared to the C (p < .05). After the fasting phase, concentrations of T3, T4, glucose, total protein and triglyceride in plasma of fasted groups were decreased, but levels of total cholesterol, aspartate aminotransferase, alkaline phosphatase and lactate dehydrogenase increased compared to the C. After re‐feeding phase, except for glucose level, all mentioned metabolites were restored in the plasma of W1 group, but total protein level and aspartate aminotransferase concentrations in plasma were not restored in W2 and W3 groups. Overall, our finding demonstrated 4 weeks of re‐feeding was too short to induce full compensatory growth in A. baerii juveniles.  相似文献   
70.
The shear viscosity of three doughs of different wheat cultivars mixed to a farinograph level of 500 BU was measured at low shear rates as a function of the shear deformation using a cone-and-plate viscometer. Cyanoacrylate adhesive was used to attach the dough samples to the instrument surfaces to eliminate wall slip. Flours used were Dragon, Kosack, and a fodder wheat. A distinct difference was observed between the viscosities of the different flour cultivars. The strongest dough (Dragon), with the highest protein content and a good resistance in the farinograph, had the highest maximum viscosity. The doughs showed distinct strain hardening, more pronounced for the strong doughs. Maximum viscosity was obtained at a strain of ≈4, almost independent of the shear rate, but at higher values for stronger doughs (5 for Dragon, 4 for Kosack, and 3.5 for fodder wheat). The maximum was most pronounced for well-mixed doughs after resting. The viscosity and its variation with strain may be used as a measure of quality; a higher viscosity and a maximum occurring at high strains indicating good quality (related to the farinogram). The viscosity gradually decreased at higher strains. Apparent viscosity increases with strain and reaches a maximum value at a common strain, which suggests the presence of entangled molecules. The increase of maximum viscosity with increase in mixing also supports this theory. Resting the dough increases the maximum viscosity, which suggests the formation of new cross-links in the nonequilibrium entangled network during resting.  相似文献   
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