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1.
This experiment was conducted to evaluate the feasibility of gamma‐irradiated soybean meal (SBM) as a dietary ingredient on the performance, body composition, and digestive enzyme activity of Caspian brown trout, Salmo trutta caspius, juveniles. Five isonitrogenous and isoenergetic diets were formulated, in which fish meal was replaced by untreated (untreated SBM), gamma‐ray irradiated at 15 (15ISBM) and 30 (30ISBM) kGy, fermented (FSBM), fermented 15 KGy irradiated soybean meal (FISBM), respectively. Juvenile fish (2.1 ± 0.3 g) were fed with the test diets for 6 wk. Final body weight was significantly affected by dietary SBM treatment with highest values in fish fed FISBM and FSBM (P < 0.05). There were no significant differences in hepatosomatic and visceral indexes, condition factor, and survival among experimental groups (P > 0.05). The carcass proximate composition of lipid and protein in Caspian brown trout in FSBM and FISBM groups was higher than that of other groups. Levels of most whole‐body amino acids were not significantly different among Caspian brown trout fed the five diets. Results of this experiment showed that replacing SBM with FSBM and FISBM in the diet significantly increased the activities of proteolytic enzymes activities (P < 0.05). However, no significant differences were observed in both amylase and lipase activities among dietary treatments. Results of this study indicated that the level of gamma radiation used did not work but fermentation of SBM did increase some growth parameters of Caspian brown trout.  相似文献   
2.
The aim of this study was a comparison of key haematological features of diploid (2n) and triploid (3n) Caspian salmon (Salmo trutta caspius). Morphometric indices of erythrocytes were determined on blood smears by light microscopy. Triploidy significantly (P < 0.001) increased all morphometric indices measured in the erythrocytes including cell size, cell surface area, and cell volume. The increase in cell size was larger for the major (27%) axis than for the minor (22%) axis, thus making erythrocytes of 3n Caspian salmon more ellipsoidal. The estimated increase in erythrocyte nuclear volume (87%) was bigger than the theoretical expected 50% increase. Haematological indices were measured manually by hemocytometry. Triploids had lower numbers of red blood cells (RBC: 1,120,000 cells/mL in 2n vs. 700,000 cells/mL in 3n; P < 0.001) but they were larger in size (mean erythrocytic volume [MEV]: 363.1 nm3 in 2n vs. 483.3 nm3 in 3n; P < 0.001). The decrease in RBC number was not compensated by the increase in MEV and, thus, triploidy affected the haematocrit (Hct: 38.8% in 2n vs. 33.06% in 3n; P < 0.05). Total blood hemoglobin concentration was lower in triploid fish (Hb: 9.9 g/dL in 2n vs. 8.9 g/dL in 3n; P < 0.05). In contrast, mean erythrocytic hemoglobin (MEH: 95 μg in 2n vs. 133.2 μg in 3n; P < 0.001) was higher for 3n Caspian salmon as a result of their larger erythrocytes, although MEH concentration (MEHC: 0.26 g/dL in 2n vs. 0.27 g/dL in 3n) did not significantly differ (P > 0.05). White blood cell (WBC) counts (lymphocytes and neutrophiles) were measured and WBC/RBC ratios were calculated. There were no significant differences in WBC (15,710 cells/mL in 2n vs. 12,683 cells/mL in 3n; P > 0.05), lymphocytes, and neutrophils as %WBC as well as WBC/RBC ratios between two ploidy levels (P > 0.05). Triploid Caspian salmon showed higher erythrocyte abnormalities such as ‘twisted’, ‘tailed’, and ‘anucleated’ cells as well as high portions of immature RBC in blood smears in comparison with diploids (P < 0.001).  相似文献   
3.
Pregnancy‐associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these proteins in the maternal blood can be a good indicator of the presence of a live embryo. As certain aspartic proteinases are present in biological fluids in physiological and pathological conditions at various concentrations, it was necessary to determine the specificity of three radioimmunoassay (RIA) systems currently used for the detection of PAG molecules. Commercially available members of the aspartic proteinase family like pepsinogen, pepsin, chymosin, rennet, cathepsin D and renin were tested in a wide concentration range (10 ng/ml – 1 mg/ml). Pepsinogen cross‐reacted in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 50 μg/ml and 500 μg/ml concentrations, respectively. In the presence of pepsin, cross‐reaction was observed in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 500 μg/ml and 1 mg/ml concentrations, respectively. Chymosin and rennet could cross‐react in RIA 2 and RIA 3, while renin and cathepsin D did not decrease the binding of the tracer to antisera more, than that of the minimal detection limit. As the plasma/serum concentrations of the examined aspartic proteinases reported in the literature were outside the concentration range where cross‐reaction was observed, it can be concluded that these RIA systems were specific for the detection of PAGs in biological fluids.  相似文献   
4.
In this approach, a derivatization method is described for monitoring of organic acids in fermentation media without any separation step. The aqueous phase of fermentation media was evaporated and heated in a silylation reagent to form trimethylsilyl (TMS) derivatives. The silylated compounds are analyzed by 29Si nuclear magnetic resonance (29Si NMR) and gas chromatography-mass spectrometry (GC-MS). 29Si NMR can qualitatively monitor the components produced in the Krebs cycle. Quantification of these compounds is investigated by using selected ion monitoring mode of mass spectrometry. In this mode, mass to charge (m/z) values of their [M - 15]+ ions, which are 465, 275, 247, 221, 335, 251, and 313 of TMS derivatives of citric, alpha-ketoglutaric, succinic, fumaric, l-malic, oxaloacetic, and palmitic (as an internal standard), acids, respectively, are used. The limit of detection and the linear working range for derivatized citric acid were found to be 0.1 mg L(-1) and 10-3 x 10(4) mg L(-1). The relative standard deviation of the method for five replicates was 2.1%. The average recovery efficiency for citric acid added to culture media was approximately 97.2%. Quantitative results of GC-MS are compared with those obtained by an ultraviolet-visible method.  相似文献   
5.
Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma (ICP). We investigated the uptaking ability of lead (Pb) and cadmium (Cd) by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index (MAI). Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of F. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves (2.21) and F. rotundifolia had the highest MAI value for shoots (2.4).  相似文献   
6.
ABSTRACT

The present study was conducted to assess the ability of AquaCrop model in predicting of grain and biological yield of rice genotypes in water management. A two-year field experiment was conducted at the experimental farm of the Iranian Rice Research Institute in Rasht, Iran from 2016 to 2017. The experiment was established in a split-plot design with two irrigation management (continuous submergence and end season water stress) as the main plot, fourth rice genotypes as the sub-plot and three replications. The goodness-of-fit between observed and simulated grain yield and final biomass was assessed by means of the coefficient of determination (R 2), the absolute and normalized root mean square errors (RMSE). The RMSEn of predicting grain yield at calibration and evaluation stages was in the range of 6–12% and 6–8% for biological yield. The results indicated that AquaCrop model is suitable to predict grain yield and biological yield of rice genotypes in northern Iran. AquaCrop model can be used to determine optimization strategies to improve the water consumption of rice genotypes.  相似文献   
7.
Ovulation rate and prolificacy are the most important reproductive traits that have major impact on the efficiency of lamb meat production. Here, we compared the whole genomes of the Romanov sheep, known as one of the high prolific breeds, and four other sheep breeds namely Assaf, Awassi, Cambridge and British du cher, to identify genetic mechanisms underlying prolificacy in sheep. Selection signature analysis revealed 637 and 477 protein‐coding genes under positive selection from FST and nucleotide diversity (Pi) statistics, respectively. Further analysis showed that several candidate genes including LEPR, PDGFRL and KLF5 genes are involved in sheep prolificacy. The identified candidate genes in the selected regions are novel and provide new insights into the genetic mechanisms underlying prolificacy in sheep and can be useful in sheep breeding programmes to develop improved breeds for high reproductive efficiency.  相似文献   
8.
Major advancement in canola breeding depends on heterotic hybrids that require high general combining ability (GCA) and specific combining ability (SCA) inbred lines. In order to estimate heritability, gene action type, GCA, SCA and heterosis and to identify superior hybrids with wider adaptation to cold, one hundred canola hybrids were produced by crossing 10 lines and 10 testers in a Line?×?Tester mating design. The F1 and F2 generations were sown in α-lattice design in 2012 and 2013 growing seasons under optimum (early October) and late sowing (early November) conditions to be evaluated for days to flowering, days to physiological maturity, number of pods per plant, number of seeds per pod, thousand seed weight, seed yield and leaf electrical conductivity. The combined analysis indicated sufficient genetic diversity in the population and significant difference between two sowing date. The Line?×?Tester analysis presented significant GCA and SCA effects for all studied traits across optimum and late sowing conditions. The main gene action type was found to be non-additive, especially incomplete dominance and over-dominance in both conditions. Narrow-sense heritability ranged from low to moderate whereas broad-sense heritability was recorded more than 60% for all of the studied traits in both generations and conditions. The average heterosis in F2 population for all studied traits was lower than that in F1 representing this fact that heterosis is generally related to the heterozygosity at the population level and poorly correlated with heterozygosity at the individual level.  相似文献   
9.
This study was conducted to investigate the impact of water salinity (ECw) and sodicity (SARw) on saturated (Ks) and relative (Kr) hydraulic conductivities in two clay (C) and sandy clay loam (SCL) soils. The results showed that the Ks decreased with increasing SARw, and in all of water quality treatments, the Ks of SCL soil was higher than that of the C soil. Sodicity effect (even at high SARw) on the Kr of clay soil was minimized by high salinity. Although Kr of both soils similarly responded to ECw and SARw, microstructure of clay soil was more sensitive to water quality. Effect of ECw on soil structure was greater than that of SARw. In order to assess the applicability of artificial neural networks (ANNs) in estimating Ks and Kr, two types of FFBP and CFBP ANNs and two training algorithms, namely Levenberg–Marquardt (LM) and Bayesian regulation, were employed with two strategies of uniform threshold and different threshold functions. Multiple linear regressions were also used for Ks and Kr prediction. Based on the ANN results of second strategy, best topology (4–5–4–1) was belonged to CFBP network with LM algorithm, LOGSIG–LOGSIG–TANSIG threshold functions, and values of MAE and R2 are equal to 0.1761 and 0.9945, respectively. Overall, the efficacy of ANNs is much greater than regression method for Ks prediction.  相似文献   
10.
Background: Bone tissue engineering requires materials that are biocompatible, mechanically suited for bone function, integrated with the host skeleton, and support osteoinduction of the implanted cells for new bone formation. The aim of this study was to compare the osteogenic potential of xenograft with hydroxyapatite/β- tricalcium phosphate (HA/β-TCP) scaffold. Methods: New Zealand rabbits (n = 9) were divided into 3 groups. Osteoblast cells were originally isolated from rabbit iliac crest and cultured in DMEM/F12. After creating a critical-sized defect (2 × 3 cm) in rabbit tibia bone, the defect was filled with an implant of HA/TCP with osteoblasts and xenograft in the hole of left (as control) and right tibia, respectively. The new bone formation and the development of bone union within the defect were evaluated by x-ray images and eosine and hematoxylin staining at 4, 8, and 12 weeks post-operation. Results: The bone partially formed in both groups was filled with osteoblast cultured on porous implants at 4 weeks. Over time, progressive bone regeneration was observed inside the pores. Moreover, a progressive vascular ingrowth and progressive integration with the host bone were obvious in xenograft when compared to HA/β-TCP. A good integration between the xenograft implants and the bone was observed radiographically and confirmed by histological section. Conclusion: The result showed that the bone defect can be repaired using both synthetic and xenograft implants. However, the xenograft showed a better osteointegration as compared to HA/β-TCP scaffold.Key Words: Osteoblasts, Hydroxyapatite/β-Tricalcium phosphate (TCP), Bone tissue  相似文献   
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