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1.
Harvesting, handling and transporting quails to the slaughterhouses, other farms and laboratories might covertly reduce their welfare. The aim of this study was to evaluate the effects of two major sources of energy in poultry nutrition on reducing transportation stress in Japanese quail (Coturnix Coturnix japonica). Male quails (n = 60) were divided into two groups. The first group was fed corn‐based diet, and the second was fed wheat‐based diet supplemented with xylanase and phytase. At the end of the experiment (day 35), quails were subjected to 80 km of transportation. Immediately on arrival and after 24 h, heterophil counts, lymphocyte counts and H:L ratios were measured. On arrival, H counts were lower, L counts were higher, and H:L ratios were lower for corn‐fed group. After 24 h, wheat‐fed group showed lower increment of H counts, greater increment of L counts and also decrement of H:L ratios rather than corn‐fed group which showed increment of H:L ratios. However, these ratios were still lower in corn‐fed group. Results indicate that corn‐based diets can help Japanese quail to better resist transportation stress, although it seems that feeding wheat‐based diets supplemented with xylanase and phytase could have positive effects for coping better with stress after journeys.  相似文献   
2.
The Penman–Monteith (FAO-56 PM) equation is suggested as the standard method for estimating evapotranspiration (ET0) by the International Irrigation and Drainage Committee and Food and Agriculture Organization (FAO). On the other hand, the Hargreaves–Samani (HS) equation is an alternative method compared with the FAO-56 PM equation. In the present study, the original coefficient C of the HS equation is calibrated based on the FAO-56 PM equation for estimating the reference ET0 from 15 meteorological stations in central Iran (about 170,000 km2) under semiarid and arid conditions. After calibration, the new values for C are ranged from 0.0018 to 0.0037. The mean bias error (MBE), the root mean square error (RMSE), and the ratio of average estimations of ET0 (R) values for all stations are ranged from 0.12 to 5.38, ?5.35 to 1.15 mm d?1 and 0.64 to 1.28 for the HS equation and from 0.12 to 2.48, ?2.2 to 0.60 mm d?1, and 1.00 to 1.05 for the calibrated Hargreaves–Samani equation (CHS), respectively. Results indicate that the average RMSE and MBE values are decreased by 40% and 66%, respectively. Relationships for calibrating the C coefficient on the basis of annual average of daily temperature range (ΔT) and wind speed (V) are proposed, calibrated, and validated. Hence, the CHS equation can be used for ET0 estimates with acceptable accuracy instead of the FAO-56 PM method.  相似文献   
3.
This study aimed to investigate the interaction between regions with different climatic conditions(arid vs. semi-arid) and management(protected vs. unprotected) on the turnover and nestedness of vegetation in relation to physical, chemical and biological properties of soils in the Ilam Province of Iran. In each of the two regions, we sampled 8 sites(4 managed and 4 unmanaged sites) within each of which we established 4 circular plots(1000 m~2) that were used to investigate woody species, while two micro-plots(1 m×1 m) were established in each 1000-m~2 plot to analyze herbaceous species. In each sample unit, we also extracted three soil samples(0–20 cm depth) for measuring soil properties. The results indicated that the interaction between region and conservational management significantly affected the percent of canopy cover of Persian oak(Quercus brantii Linddl), soil respiration, substrate-induced respiration, as well as beta and gamma diversities and turnover of plant species. The percent of oak canopy cover was positively correlated with soil silt, electrical conductivity, available potassium, and alpha diversity, whereas it was negatively correlated with plant turnover. In addition, plant turnover was positively related to available phosphorus, while nestedness of species was positively related to organic carbon and total nitrogen. According to these results, we concluded that physical, chemical, and biological characteristics of limited ecological niche generally influenced plant diversity. Also, this study demonstrated the major contribution of the beta diversity on gamma diversity, especially in semi-arid region, because of the higher heterogeneity of vegetation in this area.  相似文献   
4.
International Aquatic Research - In the present investigation, we aimed to study diversity and cell abundance of phytoplankton in the southwest of the Caspian Sea. This survey included 4 transects...  相似文献   
5.
Bursaphelenchus willibaldi, associated with trees in two separate locations in forests of northern Iran, are characterized and illustrated based on morphological, morphometric and molecular data. The Iranian population of B. willibaldi has a body length of 392–595 μm, stylet length of 12–14 μm, c‐index of 9.0–14.5 and PUS length of 51–82 μm. Males have spicules 15–18 μm long along the arch line. The Iranian population showed morphometric variations compared with the originally described samples. For example, it has a shorter body in females and males, greater c‐index, slightly greater range of V, slightly smaller range of PUS and tail length. Molecular phylogenetic analysis of the recovered populations revealed both sequenced isolates forming a clade with one European isolate of the species using Bayesian inference (BI) analysis with full Bayesian posterior probability (BPP).  相似文献   
6.
Reference evapotranspiration (ET0) can be estimated on basis of pan evaporation data (Epan), whose measurements have the advantage of low cost, simplicity of the measuring equipment, simple data interpretation and application as well as suitability for locations with limited availability of meteorological data. Epan values were converted to ET0 using the pan evaporation coefficient (Kpan). In this study, seven common Kpan equations were evaluated for prediction of ET0 in the growing season (April to October) in arid region of Iran. The Cuenca approach was best suited compared to the standard FAO Penman–Monteith method (FAO-56 PM).  相似文献   
7.
The interactive influences of water quality and surge-flow irrigation (intermittent application of water) on infiltration into a bare loam soil, packed into a long metal flume, were measured with a laboratory recirculating infiltrometer devised for the experiments. Cumulative infiltration and final infiltration rates were measured over three irrigation episodes using synthetic waters of different qualities. Four water-quality combinations of low and high salinity levels (i.e., electrical conductivity, EC=1.5 and 7.5 dS/m) and low and high degree of sodicity [i.e., sodium adsorption ratio in the range of 5-10 and 25-35 mmol1/2 l-1/2] were tested. Results showed that surge-flow cumulative infiltration of low saline waters - especially during the first irrigation episode - was lower than the corresponding continuous-flow cumulative infiltration. Conversely, it was higher for high saline and high saline-sodic waters. Effects of the water-quality treatments on final infiltration rate were similar to and in agreement with the effects on cumulative infiltration. However, the range of the final infiltration rates among surge-flow treatments was larger than with the continuous-flow treatments. Overall, infiltration was higher with surge-flow application of high saline and high saline-sodic waters than with the continuous-flow treatment. The observed contrasting results for the surge effect with the low saline, high saline, and high saline-sodic water-quality treatments were attributed to soil consolidation, formation of a depositional seal layer, and the different levels of irrigation water salinity and sodicity. It was concluded that the "surge effect" phenomena (reduction in soil infiltration caused by surge flow) under brackish (saline, sodic, and saline-sodic) water application was not pronounced and had adverse effects, in comparison to the low saline-sodic water application. Consequently, from theory, practical application of surge-flow irrigation under these circumstances, from viewpoints of infiltration reduction and irrigation efficiency improvements, is questionable.  相似文献   
8.
Data have been collected from slaughterhouses in three provinces across the Northern Iran (Gilan, Mazandaran and Golestan) from March 2004 to March 2008. These data were collected to evaluate the prevalence of hydatidosis in slaughtered cattle, sheep and goats. During the study, 3,347,797 animals were slaughtered. These included 621,686 cattle, 1,719,725 sheep and 1,006,386 goats. The prevalence of infection in cattle, sheep and goats was 12%, 14.6% and 10.1%, respectively. The association of condemnation rates with seasons was not proven statistically.  相似文献   
9.
The destruction of natural ecosystems is an important issue in many parts of the world. In the west of Iran, a vast area of the Zagros Mountain range is covered by typical vegetation including several rare plant species, of which many are currently considered endangered by anthropogenic activities. Despite the important role of soil seed banks to help conserve these degraded plant communities, the floristic studies in the Zagros forests have only focused on above- ground vegetation. In this study, the characteristics of soil seed banks and above-ground vegetation were examined at two forest sites: an undisturbed control (Un) and a disturbed (D) site. The objectives of this study were 1) to investigate the diversity of above-ground vegetation and soil seed banks in disturbed and undisturbed forests, 2) to examine the soil properties and the germination characteristics of the soil seed bank in disturbed and undisturbed oak forests and 3) to estimate the potential of soil seed banks in the restoration of disturbed sites. The results show that soil properties between Un and D sites were significantly different with higher values of pH, NH4-N, N~o,, CEC, OC, clay and canopy percentage in the Un site than in the D site. The Simpson diversity, Margalef richness and evenness indices differed significantly between sites, either for the soil seed banks or the above-ground vegetation. After a period of 26 weeks, the germination speed and the mean daily number of germinants were significantly different between Un and D sites. Without other conservation measures, soil seed banks alone cannot result in a full recovery after severe disturbances in the oak forests of Zagros.  相似文献   
10.
Alfalfa (Medicago sativa), the world’s most influential forage crop, is infected by many diseases such as alfalfa bacterial wilt disease. The causal agent of bacterial crown and root rot and wilt disease is Pseudomonas viridiflava, which is a substantial pathogen of alfalfa worldwide. This pathogen spreads through the xylem and under field conditions, plants show growth stunting, chlorosis and wilting symptoms not previously reported. In this study- the first on Pseudomonas viridiflava on alfalfa from Iran, we have investigated the pathogenicity and genetic diversity of Pseudomonas viridiflava in some parts of Iran. To survey the causal agent of the disease, symptomatic plants were collected from the main alfalfa growing area. Pathogenicity of the collected strains was confirmed on alfalfa plants under green-house conditions using a completely randomized design. Determination of bacterial strains was done based on standard bacteriological methods and PCR assay using specific primers. Effects of bacterial strains on wet weight, dry weight, stem length and root length of infected plants were measured and the data were analyzed by SAS software and Duncan’s assessment. The diversity of liquid cellular proteins of bacterial strains was examined on Polyacrylamide gel. To delineate of genetic diversity the total DNA was drawn out. Fourteen random primers were used in a RAPD test. To sketch the dendrogram, RAPD fragments were used to calculate genetic diversity with NTSYS software. This data showed pathogenicity and genetic diversity of Pseudomonas viridiflava in Iran.  相似文献   
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