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41.
Concentrations of Cd, Pb, Cu, Zn and Ni were determined in surficial sediments from eleven sampling sites in Anzali wetland. Four different methods were tested to choose the most efficient procedure for determination of the metals. The measurement of the metal levels were performed using atomic absorption spectroscopy. In order to interpret analytical results, several statistical methods were applied. There were statistically significant differences among the accumulation of the metals in sediments, while differences were not be observed among the seasons. Sampling site eight showed the lowest similarity compared to others. Kurtzfassung. Gehalte an Cd, Pb, Cu, Zn und Ni wurden in den oberflächliche sedimenten von elf probestellen aus der Anzali Lagune gemessen. Vier verschiedene Methoden Wurden untersucht um das leistungsfähigste zu wählen. Die Messungen wurden mittles flammen-AAS vorgenommen. Zur Interpretation der Ergebnisse, mehrere statistische Methoden wurden angewendet. Es gab allgemein statistische Signifikanz Unterschiede zwischen der Akkumulation der Metalle in Sedimente. Beträchtliche Unterschiede zwischen den Jahrezeiten Konnten dagegen nicht festgestellt werden. Die Probestelle acht wies die geringste Ähnlichkeit mit den anderen auf.  相似文献   
42.
Bovine cysticercosis is an important food safety issue and can cause economic loss. A cross sectional study on Taenia saginata cysticercosis was carried out in slaughtered cattle in Iran in order to determine the infection rate during a three-years period, from 2005 to 2007. A total of 4,534,105 cattle were examined by routine meat inspection. The results showed that 11,410 cattle (0.25 %) were infected with Cysticercus bovis; among those 1,041 carcasses (0.02%) were condemned. In such carcasses the metacestodes caused extensive damage in the vicinity of cysts in infected cattle. The rejected carcasses had an average of 410 thousands USD loss annually.  相似文献   
43.
To evaluate the effects of drip irrigation regimes on potato (Solanum tuberosum L.) tuber yield and quality, an experiment was conducted in 2009 and 2010. Experimental factors were the irrigation regimes including: FI, providing 100% of the water requirement of potato; IR1, providing 70% of the water requirement of potato by reducing the applied irrigation water between planting and tuber initiation by 30%; and IR2, providing 70% of the water requirement of potato by reducing the applied irrigation water during the whole growing season by 30%; and three potato cultivars Agria, Almera and Sinora. The results indicated that cultivars Agria and Almera were much better than Sinora in terms of tuber yield under all irrigation regimes. For Agria and Almera, the experiments show that the full irrigation regime had the highest yield and water productivity. For Sinora, however, deficit irrigation yields higher water productivity than the full irrigation regime. Consequently, deficit irrigation IR1 and IR2 should be applied to Sinora, but not to Agria and Almera.  相似文献   
44.
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   
45.
The present work is undertaken mainly for genotyping of kappa-casein gene in buffalo bulls. DNA was extracted from the frozen semen of nine buffalo bulls used in artificial insemination in addition to 40 blood samples of male buffalo calves for identification and genotyping of kappa-casein gene by PCR-RFLP assay. Different restriction endonucleases, including HindIII, HinfI and Taq1 were used. The PCR product of the primer specific for K2 and KY gives the specific band at size 379 and 280 bp respectively. Digestion of 379 bp fragment K2 by restriction endonuclease HindIII generated two fragments of 156 and 223 bp. For fragment 280 bp kappa-casein KY, the above mentioned endonuclease generated two fragments of 180 and 100 bp. Digestion of the 379 bp PCR product with HinfI resulted two restriction fragments of 288 and 91 bp. On the other hand, the amplified DNA (379 bp) from buffalo remained undigested by Taq1 restriction enzyme.In conclusion, the PCR-RFLP technique demonstrated that bulls were monomorphic for the kappa-casein gene; they possess only allele B in homozygosis form.  相似文献   
46.
    
In recent decades, the conversion of forest to agricultural land has been a major worldwide concern and a cause of environmental and soil-quality degradation. In this study, soil-quality indices (SQIs) were applied using several soil properties to determine the effects of land use on soil quality in a 206.50 km2 area in Kurdistan Province, Iran. The Weighted Additive Soil Quality Index (SQIw) was calculated using two scoring methods and two soil indicator selection approaches. Nine soil-quality indicators/variables were measured for 124 soil samples (0–30 cm depth). Calculated SQIs were digitally mapped with a random forest (RF) model using auxiliary data. The RF model was the best predictor of the SQI computed using the total dataset (TDS) and linear score function (SQIw-TDS-linear). Soil quality was better estimated using non-linear scoring (r2 = 0.82) than with linear scoring (r2 = 0.73). The mean values of all SQIs were significantly greater in forestland than cropland. It is clear that soil quality is considerably reduced by deforestation, and that best management practices that maintain soil quality and reduce erosion must be developed for the soils of this region if they are to remain productive.  相似文献   
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