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1.
Macrophages function as phagocytes and antigen-presenting cells in the body. As has been demonstrated in mammals, administration of clodronate [dichloromethylene bisphosphonate (Cl2MBP)] encapsulated liposomes results in depletion of macrophages. Although this compound has been used in chickens, its effectiveness in depleting macrophages has yet to be fully determined. Here, we show that a single administration of clodronate liposomes to chickens results in a significant depletion of macrophages within the spleen and lungs of chickens up to 4 d post-treatment. This finding suggests that, in order to obtain depletion of macrophages in chickens for greater than 5 d, it is necessary to administer clodronate liposomes 4 d apart. The study also showed that 2 treatments of clodronate liposomes at 4-day intervals resulted in the depletion of macrophages for up to 10 d. The findings of the present study will encourage more precise studies to be done on the potential roles of macrophages in immune responses and in the pathogenesis of microbial infections in chickens.  相似文献   
2.
The Algerian hedgehog Atelerix algirus is an insectivorous species. However, the exact composition of its natural diet remains largely undetermined, especially in relation to seasonal variations in food availability. From March to November, we simultaneously analysed the composition of 180 hedgehog faecal samples and food availability in the Soumman Valley, Algeria to assess food selection in this species. The faeces contained 196 different prey species, of which 92% belonged to the class Insecta. The highest prey species diversity was found in the Coleoptera order (100 species recorded) and the highest species occurrence was found in Hymenoptera (65% of the prey items, mainly represented by the harvester ant Messor barbarus, a crop-ravaging species). This study shows that the Algerian hedgehog is mainly a generalist species with a diet that is strongly linked to food availability. However, seasonal variations were observed in prey selection, and a notable shift in food preference was observed during autumn. The exact nature of these changes in feeding behaviour remains to be investigated, notably in relation to changes in energy requirements of this species before hibernation, in terms of quantity and/or quality.  相似文献   
3.
Vitamin A deficiency is widely prevailing in children and women of developing countries. Deficiency of vitamin A causes night blindness, growth retardation, xerophthalmia and increases the susceptibility against epidemic diseases. Among different interventions of overcoming malnutrition, biofortification is the most acceptable and preferred intervention among researchers, growers and consumers. Maize is grown and consumed in those regions where vitamin A deficiency is most prevalent; thus, targeting this crop for provitamin A biofortification is the most appropriate solution. Different breeding strategies including diversity analysis, introduction and stability analysis of exotic germplasm, hybridization, heterosis breeding, mutagenesis and marker‐assisted selection are practised for exploring maize germplasm and development of provitamin A‐enriched cultivars. Genome‐wide association selection and development of transgenic maize genotypes are also being practised, whereas RNA interference and genome editing tools could also be used as potential strategies for provitamin A biofortification of maize genotypes. The use of these breeding strategies for provitamin A biofortification of maize is comprehensively reviewed to provide a working outline for maize breeders.  相似文献   
4.
Composites based on pure Basalt and Basalt/Jute fabrics were fabricated. The mechanical properties of the composites such as flexural modulus, tensile modulus and impact strength were measured depending upon weave, fiber contents and resin. Dynamic mechanical analysis of all composites were done. From the results it is found that pure basalt fiber combination maintains higher values in all mechanical tests. Thermo-gravimetric (TG/DTG) composites showed that thermal degradation temperatures of composites shifted to higher temperature regions compared to pure jute fabrics. Addition of basalt fiber improved the thermal stability of the composite considerably. Scanning electron microscopic images of tensile fractured composite samples illustrated that better fiber-matrix interfacial interaction occurred in hybrid composites. The thermal conductivity of composites are also investigated and thermal model is used to check their correlation.  相似文献   
5.
Removal of early fruiting branches with greater potassium doses caused more source and no sink at early stages of growth, leading to improved yield, yield components, and fiber quality traits in Bt cotton. The study used manual alteration of plant architecture (F1, no branch removal; F2, removal of first fruiting branch; F3, removal of first and second fruiting branches; F4, removal of all squares from first fruiting branch; F5, removal of all squares from first and second fruiting branches) and potassium rates (50, 100, and 150 kg ha?1) in a randomized complete block design and was repeated for 2 years (2011 and 2012). Increasing potassium application increased total bolls per plant and cotton yield to the greatest levels in F3 and F5, against lowest level in the control. Ginning out turn, fiber length, seed oil, and seed protein content were influenced by fruiting branch or square removal but the difference was less. Increasing potassium improved seed and fiber quality.  相似文献   
6.
More than 50% of global soil organic carbon stocks are stored below 20 cm of soil depth capable of massively altering global C cycle and climate. However, subsoil C dynamics are largely overlooked implicitly assuming that surface and subsoil C dynamics are similar. Here, we compared the soil C dynamics in surface and subsurface soil layers in response to nitrogen and maize leaf litter additions. Soils, sampled from 0 to 5, 15 to 35, 35 to 55 and 55 to 75 cm depths, were incubated at 25°C after adding litter, nitrogen (NH4NO3) or litter plus nitrogen. Soil respiration (C mineralization) was measured throughout the incubation period. Litter addition significantly increased C mineralization in all the soil layers. However, the soil CO2 release relative to control was more than twofold higher in 15–35 and 35–55 cm soil layers than the surface layer. Nitrogen additions significantly decreased C mineralization in 0–15 cm soil, increased in 35–55 cm and had minimal effects in the 15–35 and 55–75 cm layers. Different soil C dynamics in surface and subsurface soil layers found in our study contradict the general assumption that soil C dynamics may be treated similarly along different soil depths.  相似文献   
7.
The objective of this study was to evaluate carob pods and their effect on growth performance, antioxidant activities, carcass and caecal characteristics and equilibrium modification of the caecal microbiota population of growing NZW rabbits. Eighty weaned rabbits (initial body weight: 625.00 ± 26.46 g) were randomly allocated into four dietary groups of 20 rabbits each until 90 days of age. Dietary groups were as follows: C (basal diet with no supplementation), CP1 (basal diet + 2.5% carob pods), CP2 (basal diet + 5% carob pods) and CP3 (basal diet + 10% carob pods). Rabbits given the CP2 diet had significantly higher daily and final body weights compared with the other experimental groups. The increase in inclusion rate of carob pods significantly decreased feed intake, whereas carob pods at 5% in the CP2 group recorded the best value of feed conversion ratio. Rabbits in the CP3 group showed the worst slaughter weight and carcass dressing percentage weight. No significant effect was found on meat protein and ash contents. Cholesterol, low‐density lipoprotein, high‐density lipoprotein and triglycerides decreased significantly (p < 0.05) in rabbits treated with carob pods compared with the control. Because of high content of the antioxidant compounds in CP2 and CP3 groups, the activities of glutathione peroxidase, glutathione S‐transferase, catalase and superoxide dismutase increased, whereas the concentration of thiobarbituric acid‐reactive substance decreased significantly. Rabbits given the CP2 diet had a significantly higher volatile fatty acid concentration and a lower pH in content of the caecum compared to the other groups. The data of microbial analysis for C group showed a significant increase in Escherichia coli and Clostridium counts. Lactobacillus and Bacillus counts increased significantly more in the CP2 and CP3 groups than in the other groups. In conclusion, 5% of carob pods in the diet stimulated the performance of growing rabbits, and thus, it has potential as an unconventional feed resource for rabbits without any adverse effects.  相似文献   
8.
Summary

Anthracnose, caused by Colletotrichum musae, is the major disease affecting the quality of banana fruit during storage. To control banana anthracnose, the combined effects of coatings with gum arabic [GA; at 5, 10, 15 or 20% (w/v)] and 0.75% (w/v) chitosan (CH) were investigated and compared to untreated controls. In vitro results showed significant (P < 0.05) inhibition of mycelial growth and conidial germination of C. musae in all combined treatments compared to the untreated controls after 7 d of incubation at room temperature (25°C). However, potato dextrose agar (PDA) plates amended with 10% (w/v) GA gave the most promising results among all test treatments in suppressing mycelial growth (86%) and inhibiting conidial germination (80%), while no effective inhibition of conidial germination was observed in the controls. In vivo results confirmed that 10% (w/v) GA was the optimum concentration to control fruit decay (70%), while showing efficacy on the reduction of growth of C. musae on artificially inoculated banana fruit. The combined coatings of GA + CH also significantly delayed ripening in terms of weight loss, fruit firmness, soluble solids content, and titratable acidity. These results support the possibility of using 10% (w/v) GA combined with 0.75% (w/v) CH as an alternative strategy to control post-harvest anthracnose disease in banana fruit.  相似文献   
9.
Nanotechnology is a rapidly growing field having potential applications in many areas. Nanoparticles (NPs) have been studied for cell toxicity, immunotoxicity, and genotoxicity. Tetrazolium-based assays such as MTT, MTS, and WST-1 are used to determine cell viability. Cell inflammatory response induced by NPs is checked by measuring inflammatory biomarkers, such as IL-8, IL-6, and tumor necrosis factor, using ELISA. Lactate dehydrogenase (LDH) assay is used for cell membrane integrity. Different types of cell cultures, including cancer cell lines have been employed as in vitro toxicity models. It has been generally agreed that NPs interfere with either assay materials or with detection systems. So far, toxicity data generated by employing such models are conflicting and inconsistent. Therefore, on the basis of available experimental models, it may be difficult to judge and list some of the more valuable NPs as more toxic to biological systems and vice versa. Considering the potential applications of NPs in many fields and the growing apprehensions of FDA about the toxic potential of nanoproducts, it is the need of the hour to look for new internationally agreed free of bias toxicological models by focusing more on in vivo studies. Key Words: Cytotoxicity, in vitro, Metal nanoparticles, Toxicology, Review  相似文献   
10.
Effects of waxing of the fruit and of the use of cellophane for lining storage boxes on chemical quality indices (including ethanol and acetaldehyde) and flavour scores of Feutrell's Early mandarin during storage at room conditions were determined. Maximum changes during storage of waxed mandarins in film-lined boxes occurred in ethanol contents which were followed by acetaldehyde, total soluble solids (TSS)/acid ratio, TSS and acid contents. There were negative and highly significant linear relationships between flavour scores, and ethanol content and acetaldehyde content. The r2 values indicated that over 90% of the variation in flavour scores could be explained by changes in ethanol and acetaldehyde contents whereas only 50% of the variation in flavour scores could be predicted by changes in total acid and TSS/acid ratios. There were comparatively greater increases in ethanol and acetaldehyde content, lesser increases in TSS and greater decreases in total solids of waxed mandarins during storage than those of unwaxed fruits stored in film lined boxes; the ratio of ethanol and acetaldehyde (E/A) of waxed mandarins was also higher. Decreases in citric acid content during storage correlated linearly to increases in the E/A ratio at the 1% level of significance indicating that citric acid metabolism was affected during storage of waxed mandarins at ordinary room conditions.  相似文献   
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