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Chemical composition of alfalfa silage with waste date and its feeding effect on ruminal fermentation characteristics and microbial protein synthesis in sheep 下载免费PDF全文
R. Rajabi R. Tahmasbi O. Dayani A. Khezri 《Journal of animal physiology and animal nutrition》2017,101(3):466-474
This study was conducted to evaluate the effect of feeding ensiled alfalfa with waste date on ruminal fermentation characteristics, microbial protein synthesis, protozoa population and blood parameters in sheep. Eight rams were used in a 2 × 2 change over design. Each experimental period consisted of 21 days including 16 days for adaptation and 5 days for sampling. For ensiling, fresh alfalfa (Medicago sativa L.) with different levels of waste date (Phoenix dactylifera L.) were mixed together and ensiled in 100‐l containers for 45 days. Chemical composition of silages such as dry matter (DM), crude protein, NH3‐N, organic matter, NDF, ADF and pH were determined. Then, it was used as 30% (DM basis) in diets. The experimental diets were as follows: (i) control (diet containing alfalfa silage without waste date), (ii) diet containing alfalfa silage with 5 g waste date/95 g DM, (iii) diet containing alfalfa silage with 10 g waste date/90 g DM, and (iv) diet containing alfalfa silage with 15 g waste date/85 g DM. The results of this experiment showed that adding waste date to alfalfa during ensiling, improved silage quality, DM and energy level. Total protozoa population and all of holotrich, cellulolytic and entodinia in rumen fluid were increased linearly by increasing the level of waste date. Nitrogen (N) intake, urinary N excretion and nitrogen retention were affected by dietary treatments. Also, allantoin, uric acid, total purine derivatives, microbial protein synthesis, cholesterol level and blood urea nitrogen were significantly different. In conclusion, direct ensilage of alfalfa can be attained by mixing 15 g waste date/85 g DM and positive associative effects such as increased metabolizable energy (ME) and silage quality occurred. 相似文献
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Identification of Visceral Leishmaniasis‐Susceptible Areas using Spatial Modelling in Southern Caucasus 下载免费PDF全文
This study explores the application of spatial modelling techniques to generate susceptibility maps for a neglected zoonotic disease, visceral leishmaniasis (VL), in an endemic area in southern Caucasus that includes Iran, Armenia and Azerbaijan. The social and physical environment of southern Caucasus has been mainly characterized by the presence of several factors that are strongly associated with VL, which has caused a significant number of infections during the past decade. Three popular spatial modelling techniques, consisting of the weights of evidence, logistic regression and fuzzy logic methods, were evaluated and trained using a study area in north‐western Iran where an inventory of highly infected areas and high‐quality evidential factors was available. Model performance was assessed using the receiver‐operating characteristic (ROC) approach. According to the results of these assessments, the fuzzy logic method with γ = 0.5 was chosen for the prediction of VL incidence in southern Caucasus. The susceptibility map generated using the fuzzy logic method indicated that VL followed a spatial pattern at the conjunction of the three countries, which suggests that the prevalence of VL in southern Caucasus is socio‐ecologically dependent. 相似文献
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Payam Norouzi Ahmad Rajabi Mohammad Ali Izadbakhsh Saeid Shabanlou Fariborz Yosefvand Behrouz Yaghoubi 《Irrigation and Drainage》2020,69(3):398-416
In this study, the labyrinth weir discharge coefficient was simulated using the self‐adaptive extreme learning machine (SAELM) artificial intelligence model in two cases: normal orientation labyrinth weirs (NLWs) and inverted orientation labyrinth weirs (ILWs). First, the most optimized neuron of the hidden layer was computed. The number of hidden layer neurons was calculated as 30. Also, by analysing the results of different activation functions, it was concluded that the sigmoid activation function has higher accuracy than the others. Next, the superior model was identified by conducting a sensitivity analysis. The model approximated the discharge coefficient of labyrinth weirs with reasonable accuracy. For example, the R2, scatter index and Nash–Sutcliffe efficiency coefficient for the best model were estimated as 0.966, 0.034 and 0.964, respectively. In addition, the ratio of the total head above the weir to the height of the weir crest (HT/P) and the ratio of length of apex geometry to width of a single cycle (A/w) were identified as the most effective parameters. Furthermore, the uncertainty analysis results indicated that the superior model had an overestimated performance. Then, a relationship was proposed in terms of all input variables for the superior model. © 2020 John Wiley & Sons, Ltd. 相似文献