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221.
Turmeric Powder,Curcuma longa L., in Common Carp,Cyprinus carpio L., Diets: Growth Performance,Innate Immunity,and Challenge against Pathogenic Aeromonas hydrophila Infection 下载免费PDF全文
Microbial diseases cause economic loss in aquaculture on a global scale, and the use of commercial antibiotics for disease treatment produces undesirable side effects. As many medicinal herbs have evolved a potent defense against pathogenic bacteria, there is a growing interest in these herbs as sources for natural antibacterial agents. In this context, this study was undertaken to evaluate the effect of turmeric powder (TP), Curcuma longa, on the performance and innate immunity of common carp, Cyprinus carpio L., and its challenge against Aeromonas hydrophila infection. Fish (1.4 ± 0.06 g) were fed 0.0 (control), 1.0, 2.0, or 5.0 g TP/kg diet up to satiation twice daily for 10 wk. After the feeding trial, fish of each treatment were intraperitoneally injected by pathogenic A. hydrophila, and they were kept under observation for 10 d during which the daily mortality was recorded. The growth‐promoting effect of TP was monitored and observed where fish growth and innate immunity increased significantly as dietary TP levels increased. According to the regression curve, the most suitable TP level for optimal fish growth and health was found to be 2.0 g/kg. On the other hand, TP inclusion in the fish diet did not significantly affect fish body contents. The obtained results indicate that TP supplementation is a promising immunostimulant, which could improve fish performance and innate immunity and prevent common carp aermoniosis at a level of 2.0 g/kg diet. 相似文献
222.
Leaching column experiments were conducted to determine the degree of mobility of heavy metals (HMs) and nutrients after the addition of municipal solid sewage sludge (MSS) in a sandy‐loam soil. Treatments were (1) soil application of low metal content MSS, (2) soil application of metal‐enriched municipal solid sewage sludge (EMSS), and (3) control. The MSS application represented a dose of 200 Mg dry weight (dw) ha–1. Soil columns were incubated at room temperature for 15 d and were irrigated daily with distilled water to make a total of 557 mm. Leachates were collected and analyzed for HMs and nutrients. The Ni and Pb added to soil via MSS and EMSS were found to be leached through the 20 cm columns of calcareous sandy soil although Ni and Pb concentrations in the percolate were small relative to the total amounts of metals applied. Losses of K+ from the EMSS, MSS, and control were 92.5, 82.0, and 52.5 kg ha–1, respectively. Losses of Mg2+ were in the range from 104.4 (control treatment) to 295.2 kg ha–1 (EMSS), while the loss of Ca2+ was in the range from 265.0 (control treatment) to 568.2 kg ha–1 (EMSS). The results showed that the amounts of P leached from EMSS (3.02 kg ha–1) and MSS (2.97 kg–1 ha–1) were significantly larger than those from the control treatment (1.54 kg ha–1). The geochemical code Visual MINTEQ was used to calculate saturation indices. Leaching of P in different treatments was controlled by rate‐limited dissolution of hydroxyapatite, β‐tri‐Ca phosphate, and octa‐Ca phosphate. The results indicate that application of MSS to a sandy soil, at the loading rate used in this study, may pose a risk in terms of groundwater contamination with Ni, Pb, and the studied nutrients. 相似文献
223.
This study was conducted to evaluate the redistribution of the heavy metals Cd, Cu, Pb, Ni, and Zn among different soil fractions by N fertilizers. In a lab experiment, soil columns were leached with distilled water, KNO3, NaNO3, NH4NO3, or Ca(NO3)2 · 4H2O. After leaching, soil samples were sequentially extracted for exchangeable (EXCH), carbonate (CARB), organic‐matter (OM), Mn oxide (MNO), Fe oxide (FEO), and residual (RES) fractions. Distilled water significantly increased the concentrations of Cd and Ni in EXCH fraction, while concentration of Cu and Zn did not change significantly. Application of KNO3, NaNO3, NH4NO3, or Ca(NO3)2 · 4H2O significantly increased the concentrations of Cd and Zn in EXCH fraction, while concentration of Pb and Ni was decreased. Application of all fertilizers caused an increase of Cu in the OM fraction. Moreover, leaching with these solutions significantly increased Cd [except in Ca(NO3)2 · 4H2O], Cu, and Zn concentrations in the CARB fraction, while Pb and Ni concentrations were decreased. With application of all leaching solutions, Zn in the EXCH, CARB, FEO, and MNO fractions was significantly increased, while Zn in the OM fraction did not change. The mobility index indicated that Ca(NO3)2 · 4H2O increased the mobility of Cd, Cu, and Zn in the soil, whereas NaNO3 decreased the mobility of Pb and Ni in the soil. The mobility index of Pb decreased by all leaching solutions. Thus, these results suggest that applying N fertilizers may change heavy‐metal fractions in contaminated calcareous soil and possibly enhance metal mobility and that N‐fertilization management therefore may need modification. 相似文献
224.
Ebrahimi G Ouraji H Khalesi MK Sudagar M Barari A Zarei Dangesaraki M Jani Khalili KH 《Journal of animal physiology and animal nutrition》2012,96(4):591-599
This study evaluated the effects of a commercial prebiotic, Immunogen, on feed utilization, growth rate, immunity promotion and carcass composition of the common carp Cyprinus carpio fingerlings. The fingerlings were adopted for 2 weeks and then reared in triplicate groups in 250-l tanks (n = 15 per tank with average initial weights of 11.12 ± 0.55 g). The fish fed on five isonitrogenous and isoenergetic experimental diets containing different levels of Immunogen (0, 0.5, 1, 1.5 and 2.5 g prebiotic/kg diet) to apparent satiation thrice a day for 8 weeks. Weight gain showed no differences among the groups fed different Immunogen levels. Both feed efficiency ratio and protein efficiency ratio significantly (p < 0.05) increased with increasing Immunogen levels from 0.5 to 1.5 g/kg diet. The highest protein content (p < 0.05) was found in the fish fed a diet containing 2.5 g/kg prebiotic. Haematological parameters and plasma total protein concentration were also significantly higher (p < 0.05) in the fingerlings fed diets containing 1.5 and 2.5 g/kg prebiotic in relation to the control. The control fish contained the highest mean of total bacterial counts. The lowest mean (p < 0.05) of total bacterial counts was observed in the fish fed the diet containing 2.5 g/kg Immunogen. The present study reveals that a dietary Immunogen supplementation from 1 to 1.5 g/kg is capable to improve the feed efficiency and growth performance of C. carpio fingerlings as well as their resistance to A. hydrophila infection. 相似文献
225.
Morovati H Shirvani E Noaman V Lotfi M Kamalzadeh M Hatami A Bahreyari M Shahramyar Z Morovati MH Azimi M Sakhaei D 《Tropical animal health and production》2012,44(6):1127-1129
Bovine leukemia virus (BLV), the causative agent of enzootic bovine leukosis (EBL) is an exogenous C-type oncovirus in the Retroviridae family. It causes significant economic losses associated with the costs of control and eradication programs due to carcass condemnation at slaughter and restrictions of export of cattle and semen to importing countries. The main objective of this research was to determine the seroprevalence of BLV infection in cattle herds in central region of Iran (Isfahan province) using a commercial enzyme-linked immunosorbent assay (ELISA) to detect serum antibodies against BLV. Samples of blood serum were collected from 403 female dairy cattle (Holstein-Friesian) from 21 livestock farms and 303 animals (81.9%) were BLV seropositive. A significant association was found between age as a potential risk factor and BVL seroprevalence with animals ≥ 4 years (86.6%) having a significantly (χ(2) = 35.6, p < 0.001) higher seroprevalence compared to those < 4 years (54.2%). We found no significant statistical association between seroprevalence and pregnancy, lactation status and farming systems as potential risk factors in this study (p > 0.1). It is concluded that BLV infection is a very common problem in the study area. Hence, control measures should be instituted to combat the disease and further studies are required to investigate the impact of this disease on dairy production in the country. 相似文献
226.
The use of organic residues might be appropriate in maintaining long‐term P requirement of crops. Eight plant residues and two manures in a wide range of C : N ratios were incubated for 12 weeks at 25°C, during which the processes of decomposition and formation of acid‐extractable P (P release) were assessed. Residues were incubated moist in bags and inoculated with a soil suspension. The exponential model was found to be suitable to describe decomposition and P‐release rates from residues. There were two distinct parts of P release in each time curve, which gave two rate constants and were calculated as the slope of each part. The rates of P release of the residues were considerably higher during the first 4 weeks of incubation than during the second phase of incubation (weeks 5–12). Phosphorus release by residues was similar to the decomposition pattern. The residue P content was correlated with P release, but not with decomposition rate. Mass loss and release of P were greater from sunflower and wheat residues than from sheep manure, suggesting that a high C : N ratio does not necessarily retard decomposition. The model parameters of P release were derived which are suitable to estimate the P‐fertilizer effect of organic residues. Our results suggest that the use of organic residues as a source for short‐ and long‐term P supply for crops should be encouraged. 相似文献
227.
228.
Talei Daryush Nekouei Mojtaba Khayam Mardi Mohsen Kadkhodaei Saeid 《Journal of Crop Science and Biotechnology》2020,23(4):301-309
Journal of Crop Science and Biotechnology - The polyploidy induction using mutagenic chemicals is one of the breeding approaches to improve enhancing productivity of yield and secondary metabolites... 相似文献
229.
Optimization of the extraction and analysis of phytochemicals can improve the production and quality of foods. The aim of this study is to evaluate ultrasound-assisted extraction of phenolic compounds from unripe grape (Vitis vinifera). At first stage, conventional thermal extraction was carried out in order to optimize the temperature (50, 70, 90 °C) and duration (20, 40, and 60?min) of the process (control). Investigations showed that the optimum condition of temperature and duration is 70 °C and 30?min, respectively. Then, grape pulp was treated for 30?min by ultrasound at a fixed frequency of 20?kHz. Results showed that ultrasound application increased the total phenolic content of the samples considerably. In addition, individual phenolic composition of the samples, namely rutin, gallic acid, hydroxybenzoic acid, syringic acid, p-coumaric acid, quercetin, and resveratrol were measured by HPLC. A good relation was observed between chromatographic and total phenol results. This study showed that ultrasound-assisted extraction is a sufficient method to produce verjuice as a rich and inexpensive source of antioxidants. 相似文献
230.
Electro-spun polyethylene terephthalate (PET) mat as a keratoprosthesis skirt and its cellular study
Esmaeil Biazar Mehrnaz Ahmadian Saeed Heidari K Akbar Gazmeh Seyed-Farzad Mohammadi Alireza Lashay Mohsen Heidari Hamed Eslami Mohammadali Sahebalzamani Hassan Hashemi 《Fibers and Polymers》2017,18(8):1545-1553
Artificial keratoprostheses are indispensable for visual rehabilitation in patients with end-stage corneal blindness. This study aimed to assess the biocompatibility of polyethylene terephthalate nanofibrous mats and its potential as a novel synthetic keratoprosthesis skirt material for corneal tissue engineering. Nanofibrous mats were prepared by an electrospinning method and were first treated with the CO2 plasma to yield carboxylic groups on the surface; finally, the modified PET mat was cross linked with collagen using water-soluble carbodiimide as a coupling agent. The samples were evaluated by ATR-FTIR, scanning electron microscope (SEM), contact angle, and cell culture. The cross-linking of collagen on PET surface was confirmed by ATR-FTIR spectroscopy and SEM images The 79° difference was obtained in the contact angle analysis, obtained for the collagen-cross-linked nanofibrous mat than the non-modified nanofibrous mat. Cellular investigation showed limbal epithelial progenitor cells (LEPCs) has been better adhesion, cell growth, and proliferation of collagen-crosslinked nanofibrous samples than other samples. The bioavailability of PET fibers with covalently attached collagen was found to be identical to that of PET fibers with covalent attachment is a suitable method for enhancing the biocompatibility of scaffolds special as a good skirt in keratoprosthesis designs. 相似文献