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1.
We analyzed the nuclear ribosomal internal transcribed spacer (ITS) 1 and ITS2 sequences for Bangladesh isolates of Ascaridia galli, and we determined that the sequences were unreliable as molecular markers for distinguishing A. galli from other Ascaridia species, because the sequences showed high identity with that of A. columbae. However, the ITS1 sequences were available for designing PCR primers distinguishable between Ascaridia galli and Heterakis spp. Bangladesh isolates of A. galli constituted a monophyletic clade along with other geographical isolates in the cytochrome c oxidase subunit I (COI) phylogenetic tree, however, we could not clarify the phylogenetic relationships between A. galli and other Ascaridia spp., because their available sequences in GenBank were very few. The developed PCR method using DNA from A. galli and Heterakis spp. eggs would enable differential diagnosis of the individual infections in the future.  相似文献   
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The present study was conducted for 60 days to delineate the efficacy of various dietary immunomodulators like mannan oligosaccharide (MOS), yeast extract (YE), protein hydrolysate (PH) and chlorella (CL) in Labeo rohita fingerlings. Five hundred and eighty‐five L. rohita fingerlings (average weight: 4.15 ± 0.07 g) were randomly distributed in 13 treatment groups with each of three replicates. Thirteen semi‐purified isonitrogenous (crude protein 324.7–332.5 g kg?1) and isocaloric (17.66–17.80 MJ kg?1) diets were prepared with three graded levels (1%, 2% or 4%) of immunostimulants, except the control. At the end of the feeding trial, weight gain%, specific growth rate, feed conversion ratio, leucocyte count, erythrocyte count, haemoglobin content, serum protein, globulin, albumin–globulin ratio, nitroblue tetrazolium (NBT) value and survival percentage were evaluated. Growth was significantly higher in the MOS‐fed group. All the immune parameters studied were also recorded higher in the MOS 1%‐supplemented group. The survival percentage after challenging with Aeromonas hydrophila was higher (P<0.05) in the MOS‐, YE‐ and PH‐fed groups and the lowest in the CL‐treated group. It can be concluded that dietary supplementation of MOS at a 1% dietary level promotes growth and survival in L. rohita fingerlings. In contrast, higher inclusion levels of immunostimulants led to an immunosuppressive effect in L. rohita fingerlings.  相似文献   
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Understanding the vertical and lateral distribution of soil organic carbon (SOC) and soil organic carbon density (SOCD) is indispensable for soil use and environmental management because of their vital role in soil quality assessments. Primarily, they are needed in calculating soil organic carbon storage (SOCS). The objective of this research was to provide digital maps of SOC and SOCD variation as well as their uncertainties at multiple standardized depths (H1: 0–5, H2: 5–15, H3: 15–30, H4: 30–60 and H5: 60–100 cm) using a parsimonious model with optimized terrain-related attributes and satellite-derived data. SOCS were evaluated at soil subgroup levels. An area of about 808 km2 with varying elevation, plant cover and lithology from the Miandoab region, West Azerbaijan Province, Iran was selected as a case study area. A total of 386 soil samples were collected from 104 profiles comprising various soil genetic horizons. A continuous spline function was then fitted to the target properties in advance of creating a dataset at five standard depth intervals (following the GlobalSoilMap project). These were then grouped into three classes including top (H1), middle (H2, H3 and H4) and bottom (H5) depths to ease interpretation. Static and dynamic covariates (30-m resolution) were derived from a digital elevation model (DEM) and a suite of Landsat-8 spectral imageries, respectively. Four candidate models including stepwise multiple linear regression (SMLR), random forest (RF), cubist (CU) and extreme gradient boosting (XGBoost) Tree were tested in this study. Finally, the digital maps at 30-m resolution of SOC and SOCD and their uncertainties were prepared using the best-fit model and the bootstrapping method, respectively. Four soil subgroups (Gypsic Haploxerepts, Typic Calcixerepts, Typic Haploxerepts and Xeric Haplocalcids) were identified across the study area. The covariates had variable contributions on the evaluated models. The XGBoost Tree model generally outperformed other models for prediction of SOC and SOCD (R2 = 0.60, on average). Regardless of soil subgroups, the uncertainty analysis showed that the SOCD map had a low prediction interval range value indicating high accuracy. Additionally, the highest SOCS and SOCD was observed at the top followed by middle and bottom depths in the study area. All subgroups exhibited a decreasing trend of SOCD with increasing depth. A similar trend was also observed for SOCS. The highest SOCD (on average) was observed in Gypsic Haploxerepts (4.71 kg C/m2) followed by Typic Calcixerepts (4.46 kg C/m2), Typic Haploxerepts (4.45 kg C/m2) and Xeric Haplocalcids (4.40 kg C/m2). Overall, the SOCS normalized by area within soil order boundaries was greater in Inceptisols than Aridisols across the study area. The findings of this study provide critical information for sustainable management of soil resources in the area for agricultural production and environmental health in the Miandoab region of Iran.  相似文献   
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For effective varietal improvement of horticultural crops peach (Prunus persica) and nectarine (Prunus persica var. nucipersica), information about their population structure and genetic relatedness plays an important role. In this study we used retrotransposon-based markers (iPBS) to estimate the genetic diversity and population structure of 48 peach and nectarine genotypes from various distinct geographical regions of Punjab and Khyber Pakhtunkhwa, Pakistan. A total of 461 alleles were identified from PCR amplicons derived from nine iPBS primer pairs with an average of 8.5 alleles/locus. Among all four groups the genotypes collected from Swat and Hunza had the highest and the lowest expected heterozygosity, unbiased expected heterozygosity and Shannon’s information index, respectively. We constructed a Neighbour-Joining dendrogram and performed principal coordinate analysis based on the distance matrices, and both forms of analysis grouped the 48 genotypes into two distinct clusters. The STRUCTURE software distributed the forty-eight genotypes into two main populations (k?=?2) indicating a low diversity between genotypes collected from Chakwal, Swat, Mansehra and Hunza.

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An experiment in seed morphology and seed germination techniques of Albizia procera was carried out in the nursery of the Forestry and Wood Technology Discipline,Khulna University,Bangladesh in order to discover the source variation in seeds and pre-sowing treatment effects on seed germination.Mature seeds of A.procera were collected from healthy trees in home garden plantations from five different districts in Bangladesh and treated with four pre-sowing treatments,i.e.,control,immersion in cold water (4°C for 24 h)and immersion in hot water(80°C for 10 min and 100°C for 1 min).The average length,width and thickness of seeds were calculated as 0.502±0.485,0.420±0.060 and 0.191±0.118 cm,respectively.Germination was conducted in poly-bags with a mixture of topsoil and cow dung in a ratio of 3:1.The results revealed that pre-sowing treatments affected the rate of germination of seeds,which significantly increased the germination percentages of seeds in hot water treatments compared with those in control (60.60%)and the cold water treatment(4°C for 24 h,63.53%).The highest germination success was 82.07%in the treatment of immersion in hot water(80°C)for 10 min,followed by 79.00%in immersion in hot water(100°C)for 1 min.Germination started 4 to 6 days after seed sowing and completed in a period of 22 to 25 days in all treatments.ANOVAs showed statistically significant differences(p0.05)in seed germination starting dates,closing dates,germination percentages and rates of germination among treatments,but no significant differences in seed germination starting dates,closing dates,germination period,germination percentages and rates of germination among the seed sources.The study also revealed that the interaction between seed source variation and treatment effect significantly differed in seed germination starting dates,closing dates,germination percentages and rates of germination. The hot water(100°C for 1 min)treatment is recommended for seed germination of A.procera in rural Bangladesh.  相似文献   
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The present work was conducted to study the comparative efficacy of two anti-protozoan (babesicidal) drugs on the recovery and health of horses. A total of 80 horses, showing typical clinical symptoms of the disease, were selected for this study; the presence of babesiosis was confirmed through blood smear examination. These animals were divided into two groups i.e. A and B. Horses of Group A, were treated with diminazene diaceturate, while horses of Group B were treated with diminazene aceturate. Efficacy of the drugs was determined by the reversal of clinical signs and a negative blood smear examination. The efficacy of diminazene diaceturate was demonstrated to be 80% while diminazene aceturate was found to have 90% efficacy against babesiosis.  相似文献   
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Sweet and sour are the most important taste of blueberries, and they are produced by sugar and acid, respectively. Their contributions to the taste depend not only on the levels of sugar and acid, but also on the types and relative proportions of sugar and acid. Therefore, it is very important to evaluate the composition and levels of sugar and acid in blueberries. Regional differences and variety diversity also affect the sugar and acid characteristics of fruits. Therefore, this study selected two main producing regions in northern China(Weihai and Yingkou) to examine the sugar and acid characteristics of 11 common blueberry cultivars. The indexes measured included soluble sugars, organic acids, soluble solid content and titratable acidity. The results showed that glucose and fructose were the major sugars, and citric acid and quinic acid were the major organic acids. Correlation analysis showed that glucose, fructose, and sucrose were positively correlated with total sugar content; the citric acid content was positively correlated with the titratable acidity and total organic acids. Titratable acidity, glucose, fructose, sucrose, total sugar content, citric acid, shikimic acid and total acid content of the blueberries varied significantly between regions(P0.05). In general, compared with Weihai blueberries, Yingkou blueberries had higher sugar content and lower acid content. The results of this study may provide useful references for the evaluation of sweet and sour flavors and cultivar selection of blueberries.  相似文献   
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