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21.
This study investigates the effects of replacing fish oil with two vegetable oils (Sunflower oil and Soybean oil) on growth performance, salinity tolerance, hematological and serum biochemical profile of Rutilus rutilus over 56 days. Five diets were supplemented with 8% of either fish oil (FO) (control), sunflower oil (SFO), and soybean oil (SO) or a combination of 4% FO with 4% SFO and 4% FO with 4% SO, respectively. Triplicate groups of fish (24 fish per tank with an average body weight, of 5.52 g) were assigned to each diet. Blood samples were taken from the caudal vein of 75 apparently healthy fish at the end of trial. Hematological values of the blood samples were determined using standard techniques. At the end of the experiment fish were exposed to salinity stress. The results showed that the best growth performance was in fish fed the control diet, but the differences were minor among treatments containing vegetable oils (P > 0.05). Serum cholesterol and glucose concentrations were significantly higher in fish fed dieta containing vegetable oils (P < 0.05). Red blood cell count (RBC), hematocrit (Ht) and hemoglobin (Hb) in groups fed diets containing SFO and SO were higher than other groups (P < 0.05). There was no significant difference in survival after 48 h salinity stress (P > 0.05). These results indicate that in cases where fish oil is scarce or expensive, vegetable lipids can be used as replacements without any serious negative growth performance and health impacts.  相似文献   
22.
This research was carried out to estimate yield stability of 18 barley breeding lines using different parametric and non-parametric statistics across 15 environments during 2012–2015 growing seasons. The results of combined analysis of variance (ANOVA) and additive main effect and multiplicative interaction (AMMI) analysis showed that environments (E), genotypes (G), GE interaction, as well as the first four interaction principal component axes were highly significant, suggesting that the lines interacted differentially with environments, so further general adaptability and stability analysis across environments should be followed before being introduced for cultivation. Based on correlation coefficient and principal components analysis (PCA), most of the non-parametric statistics were significantly inter-correlated with parametric statistics, hence seem to be suitable alternatives to complement parametric statistics. Furthermore, according to the static and dynamic concepts of stability, the results revealed that stability statistics can be clustered into three groups. The overall stability analysis following different stability methods concluded that four lines (G5, G7, G17 and G20) were highly stable for grain yield in rain-fed conditions of subtropical regions of Iran. Thus, these lines can be recognized as the most stable lines for cultivation in diverse environments of semi-warm regions of Iran.  相似文献   
23.
Between 2013 and 2015, several surveys were conducted throughout forest areas in the north of Iran with the aim of isolating and identifying fungi present on trees showing decline symptoms. Fungal species, isolated from symptomatic wood tissues of various tree genera, including Zelkova, Acer, Parrotia, Quercus, Diospyros, Fagus, Fraxinus, Populus, Pinus, Pterocarya, Gleditsia, Carpinus, Ulmus, Crataegus, Alnus, Mespilus, Punica, Cydonia, Cupressus and Prunus, were morphologically identified and characterized. A molecular identification based on comparisons of DNA sequences of the β‐tubulin gene allowed us to identify seven species belonging to Phaeoacremonium; namely, Phaeoacremonium parasiticum, Pm. alvesii, Pm. minimum, Pm. iranianum, Pm. scolyti, Pmfraxinopennsylvanicum and Pm. croatiense were isolated and identified. Phaeoacremonium minimum was the most common species and isolated from Gleditsia caspica, Parrotia persica, Cydonia oblonga and Alnus glutinosa. Pathogenicity on selected plants using a mycelium plug inoculation method revealed that most of these species are pathogenic to all the tested trees, with Pm. parasiticum and Pm. minimum being the most pathogenic species. According to host plant species and geographical distribution, the majority of Phaeoacremonium species found represent new records. This is also the first report of Pm. croatiense in Iran and outside Croatia.  相似文献   
24.
Helicobacter‐like organisms are frequently found in canine stomachs, but the relationship between such organisms and gastric pathology has not been established. However, some such organisms have zoonotic importance. The aims of this study were to evaluate the morphological and biochemical characteristics of cultivable canine gastric Helicobacter‐like organisms (GHLOs) in pets and stray dogs and their prevalence in these two groups of dogs. Specimens were taken by gastroscopy from 30 clinically healthy stray dogs and 30 pet dogs. Cultures were positive from biopsies of 11/30 of stray and 6/30 of pet dogs. The isolated Helicobacters were observed by light microscopy and studied by biochemical, physiological and PCR analysis. Some of the isolated GHLO's displayed atypical shapes that were similar to Helicobacter pylori or Helicobacter acinonychis in stray dogs’ cytological examinations. They had 2–3 helices and were smaller than other canine GHLOs. One of these atypical Helicobacter strains was cultured. It was not possible to distinguish such strains by routine PCR and biochemical evaluations. Electron microscopy showed a smaller Helicobacter (2 μm in length) with 2 or 3 helixes. This study demonstrates that not all canine gastric Helicobacters are 5–15 μm in length, as has been previously proposed, and portrays the need for further investigation of canine GHLOs.  相似文献   
25.
Apparent crude protein (ADCCP), crude fat (ADCCF) and gross energy (ADCGE) digestibility coefficients of several typical and novel feedstuffs were determined to be employed in the formulated diets of subadult beluga (17.70 ± 0.234 kg) diets via two faecal collection methods of settlement (SFCM) and stripping (StM). The tested feedstuffs included three fish meals, three terrestrial animal by‐products, three plant protein concentrates, nine high‐protein plant meals and three low plant protein meals. ADCCP values varied in different fish meals ranging from 89.5% for Mexican sardine meal to 93.2% for anchovy meal with SFCM. ADCCP values for plant protein concentrates ranged from 82.8% for wheat gluten meal to 92% for soy protein with SFCM. ADCCP ranged from 37.2% for whole wheat to 75.6% for spirulina meal with SFCM. ADCGE was lower in low‐protein plant meals (64.1%) in comparison to high‐protein plant meals (70.2%). Fish meals showed the highest ADCCF values. A significant (< 0.05) quadratic regression relation (r2 = 0.92) was observed among in vivo ADCCP of five feedstuff classes fed to beluga and in vitro ADCCP. The differences among ADC values appear to be significantly related to the effects of feedstuffs and therefore diet and faecal collection methods.  相似文献   
26.
The concentration of polycyclic aromatic hydrocarbons (PAHs) was determined in seawater, sediment, and Rock oyster Saccostrea cucullata collected from four sampling sites in the inter-tidal areas of Bushehr province. The total concentrations of 14 PAHs varied from 1.5 to 3.6 ng/L in seawater, 41.7 to 227.5 ng/g dry weight in surface sediment, and 126 to 226.1 ng/g dry weight in oyster tissue. In comparing PAH concentrations among the three matrices in Bushehr province, data showed that the pattern of individual PAHs in seawater, oyster, and sediment were different. The oysters tended to accumulate the lower molecular weight and the more water-soluble PAHs. Sediment samples were distinguished from the sea water and oyster samples by the presence of high molecular weight PAHs, especially six-ring PAHs. Three- and four-ring PAHs were the most abundant compounds among the 14 PAHs investigated in surface seawater, sediment, and oyster samples. As expected, differences in octanol/water partition coefficient among individual PAHs and the greater persistence of the higher molecular weight PAHs contributed to the accumulation patterns in oyster and sediment. The results of the study suggested that the main sources of PAHs in the seawater and sediment in the region were mixed pyrolitic and petrogenic inputs.  相似文献   
27.
Topography has an important influence on the distribution of soils and their properties, especially in hilly lands, and related data are easily available, measurable and recognizable from digital elevation models (DEMs). To our knowledge, little attention has previously been paid to the effect of DEM attributes on the distribution of soils, using ordination methods. The objective of this study was to analyze relationships between topographical properties derived from DEM and soil distribution and to discuss their applicability in Digital Soil Mapping (DSM). The study was carried out in the Borujen area of central Zagros, Iran. A total of 13 plots (each one of 6.75 ha) were set up to calculate the percentages of the dominant soil series. Fifteen DEM attributes, including slope, aspect, curvature, maximum and minimum curvature, planform curvature, profile curvature, tangent curvature, wetness index, power index, sediment index, area solar radiation, direct radiation, diffuse radiation and direct duration were also computed. Canonical Correspondence Analysis (CCA) was used to summarize the data set and to evaluate the expected relationships. The results obtained show that there was a relatively strong correspondence between soils' series distribution and topographical properties. The DEM attributes that best related to the first axis were maximum curvature, slope and sediment index, all of which significantly positive correlated, and wetness index, direct duration and minimum curvature, all of which were negatively related. The second axis showed a negative trend with wetness index, direct duration and aspect, and a positive trend with sediment index and slope. These gradients were closely related to the first three canonical axes and explained 71.8% of the total variance of the soil series. The residual variance (28.2% of the total variance) was related to other soil forming factors, like parent material and vegetation cover, which were not investigated in this study. Considering that DEMs are still the most important source of environmental information, understanding the role of topographical factors in a region should help us to identify soils and their properties better and enable us to apply these derivates as input data in DSM.  相似文献   
28.
In the present study, we examined the mortality rate, egg production, and clinical signs of quail experimentally infected with a field isolate of A/Chicken/Iran/339/02 (H9N2) avian influenza virus obtained from an infected commercial layer farm with severe morbidity and mortality. A total of 120 quail at 14 days old were randomly divided into four groups of vaccinated (B and C) and unvaccinated (A and D) birds. Vaccination was done on days 20 and 32, and viral inoculation of birds in groups C and D was then carried out on day 43. For evaluation of viral transmission, at 24 hr postinoculation additional unvaccinated birds were placed in direct contact with challenged birds. All the birds were evaluated for clinical signs, egg production, antibody production, viral titration in lung homogenates, and viral transmission following inoculation. All unvaccinated-challenged birds were infected and showed clinical signs, whereas the infection rate along with clinical signs of vaccinated-challenged birds reached 30%-40%. Although vaccination induced high antibody titers, reduction in food and water consumption was evident in this vaccinated-challenged group compared with the unchallenged control group. These results could indicate that inactivated vaccine did not fully prevent the infection, although it was capable of protecting birds against clinical signs and significantly decreased viral titers in lungs after intranasal challenge.  相似文献   
29.
Sulphuric acid-modified bagasse has been used as low-cost adsorbent for the removal of methylene blue (MB) dye from aqueous solution. In order to remove organic compounds that contribute to chemical oxygen demand (COD), pretreatment with thorough washing of adsorbent using boiling distilled water was performed instead of conventional washing using distilled water at room temperature only. This has resulted in the highest efficiency of color removal of 99.45% and COD reduction of 99.36% for MB dye solution at pH 9. Effects of initial pH, dye concentration, adsorbent dosage, temperature, and contact time have been studied. The adsorption of MB dye was pH dependent. Langmuir and Freundlich isotherm models were tested on the adsorption data. The kinetic experimental data were analyzed using pseudo-first order, pseudo-second order, and the intraparticle diffusion model in order to examine the adsorption mechanisms. The adsorption process followed the Langmuir isotherm as well as the Freundlich isotherm and pseudo-second-order kinetic model. The process was found to be endothermic in nature.  相似文献   
30.
This experiment was conducted in split plots based on randomized complete block design with three replications. Three crop sequences: (R1): chickpea, sunflower, wheat, and canola; (R2): green manure, chickpea, green manure, wheat, green manure, and canola; (R3): canola, wheat, and canola were used as main plots. Sub plots consisted of six methods of fertilization: (N1): farmyard manure; (N2): compost; (N3): chemical fertilizers; (N4): farmyard manure + compost; (N5): farmyard manure + compost + chemical fertilizers; and (N6): control. Results showed that the enzyme activities were higher in the N4 treatment. The highest amount of acid phosphatase, protease, dehydrogenase activity, and grain yield was observed in R2 sequence. The highest urease activity (58.6 µg g?1 h?1) was obtained in R2N4 treatment. In R2N4 treatment using in-farm inputs, a non chemical fertilizer system can be carried out to improve soil biological activity.  相似文献   
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