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301.
Toxoplasmosis is a widespread zoonotic disease that causes significant morbidity and mortality in human fetus and in immunocompromised patients. Moreover, it becomes a major cause of abortion in sheep and goats. Since consumption of meat of infected lamb and goat is considered as the main sources of human infection in Iran, this study was undertaken to determine the prevalence of Toxoplasma infection in edible tissues of sheep and goats in Shiraz in 2008. Samples of brain, tongue, liver, and muscles of neck, intercostals, and femoral were taken from 56 sheep and 22 goats and tested by PCR. The total prevalence of Toxoplasma infection among animals was found to be 33.3%. Five out of 22 goats (22.7%) and 21 out of 56 sheep (37.5%) were infected by Toxoplasma. Differences between the prevalence rate of infection among females (nine out of 14 = 46%) and males animals (12 out of 45 = 29.5%) was significant (P = 0.013). Furthermore, a positive correlation was found between the age of animals and the rate of infection; animals greater than 2 years old showed a higher rate of infection (47%) in comparison with those less than 2 years old (25%, P = 0.04). The highest infected tissue was tongue (21.8%) followed by brain (19.2%) and femoral and intercostal muscles (17.9%). This study demonstrated a high level of Toxoplasma infection in slaughtered animals in Shiraz and these should be considered as the main sources of infection for human population in the region.  相似文献   
302.
The importance of the linkage between nutrition and health is a hot issue. Like other food-related sectors, the meat industry is undergoing foremost transformations, driven among other things by changes in consumer requirements. The present study was designed to evaluate the lipid stability and antioxidative potential of leg and breast microsomal fraction of broiler meat fed on ALA and ATA. For the first 3 weeks of growth, broilers were fed on feed supplemented with ATA (200 mg/kg of feed) and during the last 3 weeks broilers were fed on feed supplemented with ALA (25, 75, 150 mg/kg of feed) and a constant level of ATA (200 mg/kg of feed). The body weight of the carcass was measured after every week of growth until 6 weeks. Positive correlation between the antioxidant activity and the TPC was observed. Higher values of TBARS were detected in leg muscles than in breast muscles. HPLC data revealed ALA and ATA contents were higher in T(4) (leg, 5.55 ± 0.19 and 3.87 ± 0.15 μg/mg of protein; breast, 5.63 ± 0.20 and 2.03 ± 0.10 μg/mg of protein, respectively) and lowest in T(5) (ALA, leg, 1.40 ± 0.06 μg/mg of protein; breast, 1.54 ± 0.05 μg/mg of protein; ATA, leg, 1.25 ± 0.06 μg/mg of protein; breast, 0.63 ± 0.008 μg/mg of protein), in which the only oxidized oil was used. Oxidized oil in feed reduced weight gain and increased TBARS, whereas TPC, DPPH, ALA, and ATA values decreased in both leg and breast meat.  相似文献   
303.
To investigate the seed protein and major mineral nutrient (Fe, Zn, P, and N) contents and their accumulation procedure in the seeds of common bean (Phaseolus vulgaris L.), a biennial experiment was conducted under two contrasting moisture regimes (normal irrigation and water deficit). Seed reserves of eight genotypes (WA4502-1, WA4531-17, Akhtar, D81083, AND1007, KS21486, MCD4011, and COS16) were investigated at four stages of seed filling period (SFP). Split-plot experiments were performed as randomized complete block design with four replications. The results showed significant differences in the evaluated characteristics in both factors, the genotypes and the moisture regimes. Fe content of the seeds was affected the most by drought stress and reduced in all stages, while seed nitrogen and protein contents were affected the least under stress condition. The percentages of reductions due to water deficit were higher in stage 1 for Fe, stage 2 for Zn, and stage 4 for P and N. In the stage 3, minerals had the least changes. Nitrogen content of the seeds at mid-stages of SFP increased slightly under drought stress. Drought stress also caused 39–69% reductions in the grain yield of the genotypes. Under drought stress condition, the concentrations of Fe and N in the white bean seeds were less than that of the red and the Chitti genotypes. However, the seed P contents of the white bean seeds were higher than that of the other genotypes.  相似文献   
304.
Citrus, especially Kinnow, fruit yield and quality in Pakistan is not competitive with other countries, which could be mainly attributed to a lack of good nutrient management for citrus orchards. Many of the soils under these orchards have been reported as deficient in potassium (K). Therefore, work was initiated for improving citrus fruit yield, size, and quality through K nutrition management. Experiments were conducted in four districts of Punjab including Faisalabad, Toba Tek Singh, Jhang, and Sargodha and four rates of potash, i.e., 0, 50, 75 and 100 kg dipotassium oxide (K2O) ha?1 were applied using sulfate of potash (SOP) along with recommended rates of phosphorus (P) and nitrogen (N). Soils of all the selected sites were clay loam or sandy clay loam and deficient in K. The leaf analysis also showed that all the selected orchards were deficient in K. Application of K increased the fruit yield and quality but K at100 kg K2O ha?1 was more effective in increasing the fruit weight and size, and peel thickness than other K rates in all the selected orchards. Juice volume and percentage significantly increased when K was applied at 75 kg K2O ha?1 at all sites. Nutrient uptake like K, P, and N enhanced with the increase in K application rate, however, the highest calcium (Ca)+ magnesium (Mg) was recorded at 50 kg K2O ha?1. The results indicated that all rates of K application improved the fruit yield and quality and reduced fruit dropping, however, 75 kg K2O ha?1 rate was more effective as juice volume and percentage, total soluble solid (TSS)/acid ratio and nutrient uptake showed significant improvement.  相似文献   
305.
Drought is currently one of the most severe abiotic factors limiting agricultural production. The high rates of population growth and global warming are expected to further exacerbate the threat of drought, especially in areas with a semi-arid climate as in the Middle East region. Selecting genotypes for improved drought tolerance has long been of interest for those involved in horticulture. The present research investigated the reaction of seven 10-year-old olive genotypes to drought stress in Dallaho Olive Research Station, Iran. To determine the reaction of genotypes to drought stress, physiological and biochemical characteristics, fruit and oil yield, and water use efficiency were measured. The results showed that different genotypes react differently to drought stress while drought decreased vegetative and reproductive traits such as shoot length and diameter, relative water content of the leaves, Ca and K percentage, and fruit yield. Finally, Dd1 and Bn6 showed the highest oil and fruit yield per hectare and the highest water use efficiency. In addition, Bn3 had a favorable status in most of the measured parameters. So, they can be suggested as the genotypes that are tolerant of drought stress. The results also showed that olive yield and irrigation management can be improved by applying proper irrigation levels and using tolerant genotypes.  相似文献   
306.
Land-use changes and land cover strongly influence carbon stock and distribution within ecosystems. Changing the land-use from natural forest to other land-uses has been more rapid in the past few decades than at any time in Iran’s history. In this study, we investigated the effects of changing the land-use from natural forest to other land-uses on carbon stocks in northern Iran. We selected five sites for this study: (I) a natural forest, (II) an agricultural field and (III) plantations of three different species (Alnus subcordata. L, Acer velutinum.Boiss and Cupressus sempervirens). We examined the effects of land-use changes on: (I) soil carbon stock (0–50 cm depth), (II) biomass and carbon content of grassy vegetation and litter and (III) above- and below-ground biomass C in trees. Soil C stock was higher under A. velutinum and C. sempervirens whereas it was lower under A. subcordata and agricultural sites. Biomass and C content of grassy vegetation were significantly higher at A. velutinum and C. sempervirens plantations. However, litter biomass and C content were significantly higher at the natural forest site. Natural forest had the highest amount of C content in above- and below-ground biomass. Total ecosystem C stocks declined following land-use changes.  相似文献   
307.
Juniperus species (juniper) are resistant to drought and have medicinal properties. In order to investigatethe condition of juniper reproduction and prevent a decline in its area, largely caused by problems in natural regeneration, the asexual reproduction of juniper has received special attention besides its sexual propagation. Among the six species of juniper in Iran, the most abundant are Juniperus polycarpos and J. excelsa. Juniperus polycarpos is ambi-sexual and J. excelsa unisexual. We show that collecting seeds in September provided for better germination than in November. In sexual propagation 82.0% and in asexual (graft) 47.6% success were achieved. Compared to a mixture of water, lime and hormones, a natural treatment of only water had better results. Diurnal change of temperature increased germination of juniper seeds over a constant temperature. Aphyllous stem cuttings from mature and old trees are less successful in rooting than leafy cuttings of juniper saplings. A treatment with Aaterra significantly reduced the percentage of rooted cuttings and total root length. Aliette, Fongarid, Octave, Benomyl, Delsene M and Maneb fungicides significantly increased the percentage of rooted cuttings but did not affect total root length. Autumn explants formed more calli than spring explants. Successful multiplication was achieved by treating buds with a mixture of 0.7% polyvinyl pyrrolidone (PVP) and 2% sucrose and cultured in a basal MS or WRC medium, with a maximum number of new buds. In consideration of extracted material of juniper species in remedy of infectious, fungus, contagious diseases as well as for drought resistance and longevity of this species in severe arid environmental conditions and various industrial applications, reproduction and seed production by micro propagation and biotechnology are necessary.  相似文献   
308.
1. In this study, neural network (NN) and response surface (RS) models were developed to investigate the response [average daily gain (ADG) and feed efficiency (FE)] of young broiler chickens to dietary protein and lysine. For this purpose, data on their responses to dietary protein and lysine were extracted from the literature and separate NN and RS models were constructed.

2. Comparison between the NN and RS models revealed higher accuracy of prediction with the NN models compared to the RS models. In terms of R 2 values, the NN models developed for both ADG (R 2 = 0.923) and FE (R 2 = 0.904) were far superior to the RS models (R 2 for ADG = 0.511; R 2 for FE = 0.67). This suggests that the NN models can serve as an alternative option to conventional regression approaches including use of RS models.

3. Optimisation of the NN models developed for response to protein and lysine showed that diets containing 220.7 (g/kg of diet) protein and 12.85 (g/kg of diet) lysine maximise ADG, whereas maximum FE is achieved with diets containing 241.3 and 13.12 (g/kg) protein and lysine, respectively. Based on the optimisation results, optimal dietary protein and lysine concentrations for maximum FE in broiler chickens during the starting period are higher than for ADG.  相似文献   

309.
Different shapes of dispersed phase such as sphere, laminar and fibrillar can form in the matrix phase of polymer blends. Production of blend fibers in melt spinning process can result more effective in fibrillar phase morphology formation than in other processes. In this research, the matrix-fibril morphology development during the melt spinning of polypropylene/poly(butylenes terephthalate) was studied. The shapes of blend dispersed phase collected from different zones of the melt spinning line were evaluated by scanning electron micrographs (SEM) and rheological mechanical spectra (RMS). The results showed that fibrillar shape could not be created in the PP/PBT blend fiber samples exited from the spinneret orifice (gravity spun fibers) at low contents (5 percent) of the PBT dispersed phase. However, a complete fibrillar structure was formed in all the as-spun PP/PBT blend fiber samples (melt drawn). The rheological evaluations confirmed a network structure resulting from fibril formation for the samples with high contents (20–40 %) of the PBT dispersed phase and the formation of spherical shape with low contents (5–10 %) of the PBT dispersed phase in matrix of the blend fibers. It was observed that the flow fields of processing zones and blend ratio, in producing the blend fibers, have intensive effects on morphological variations; besides there was a strong relation between the mechanical and morphological properties.  相似文献   
310.
A new method for determining the dye distribution in the cross section of polyamide rods from the scanner data is presented. Three commercial disperse dyes are used for dyeing purposes and two series of dyed samples are prepared. The first set is the samples with the full diffusion of dyes within the cross section of rods that used as the reference samples while the second set includes samples with different depths of penetrations, hence they benefit from non homogenous dye distribution in their cross sections. A conventional scanner is characterized with the ColorChecker SG and the transformation matrix is computed to convert the RGB values of samples to the CIEXYZ data. The spectral reflectances as well as the RGB values of the cross sections of the full diffused dyed samples are measured and the classical version and the weighted version of principal component analysis technique are employed to estimate the spectral behaviors of homogenous dyed samples from the CIEXYZ values obtained from the corresponding RGB data. Finally, the well known Kubelka Munk equation is employed to estimate the concentration of dyes in the cross sections of samples. The work is extended to non homogenous dyed samples to find the spatial distributions of dyes over the cross sections of rods. Similar to full diffused dyed samples, the spatial reflectance spectra of the cross sections are firstly estimated from the measured RGB values and then the spatial concentrations are computed. The plotted concentration-distance profiles confirm the classical variations of dye concentrations over the cross sections of dyed rods similar to those that are obtainable by conventional methods such as multiple membranes and Boltzmann-Matano as well as laser scanning confocal microscopy methods.  相似文献   
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