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41.
1. A 6-week study was conducted to investigate the effects of phytase and hydroalcoholic extract of Withania somnifera root (WS) on productive performance and bone mineralisation of laying hens in the late phase of production.

2. Diets were arranged factorially (3?×?2?×?2) and consisted of a positive control with adequate Ca (4·37%) and nonphytate P (NPP; 0·39%) and a negative control diet with Ca (4·06%) and NPP (0·36 %); three concentrations of Withania somnifera (0, 65 and 130?mg/kg diet); and two concentrations of microbial phytase (0 and 300 U/kg diet).

3. A total of 144 72-week-old Hy-Line W36 laying hens were randomly assigned to the 12 treatment groups. Each treatment was replicated 4 times (4 x 3 hens). Egg production and egg weight were recorded daily, while feed intake and egg quality traits were recorded every two weeks. Bone quality traits were evaluated at the end of experiment.

4. Withania somnifera supplementation increased egg production and lowered egg weight only in the second two weeks of the experiment. Addition of phytase significantly depressed specific gravity of the eggs for the entire experiment period. No dietary treatment effects were observed on egg shell thickness and yolk weight.

5. Withania somnifera at 130?mg/kg did not affect feed intake. The hens fed on the positive control diet had higher albumen weight than the negative control diet in the second two-week period. Supplementation of the positive control diet with 65?mg/kg Withania somnifera in the absence of phytase significantly improved shell weight compared with the negative control (5·779 vs. 5·273?g respectively).

6. Supplementing Withania somnifera significantly improved Ca and P retention in tibia bone. In addition, an increase in tibia bone P was observed with phytase supplementation. There were significant interactions between Withania somnifera content and phytase for tibia bone Ca and P.

7. The results of this experiment indicated that dietary Withania somnifera has beneficial effects on tibia bone Ca and P content, and phytase improved tibia bone P retention without adverse effects on productive performance.  相似文献   
42.
We measured erodibility and mean weight diameter (MWD) of soil aggregates in different parts of a forest road. Samples of topsoil were collected from cutslope, fillslope, road surface and forest ground to assess the texture, bulk density, moisture, CaCO3 and organic matter. Soil aggregate stability was determined by wet sieving. Soil erodibility on the road surface was 2.3 and 1.3 times higher than on the fillslope and cutslope, respectively. The forest soil had the lowest erodibility. Aggregate stability of cutslope and road surface were low and very low, respectively. There was a significant negative relationship between cutslope erodibility with CaCO3 and sand content. Cutslope erodibility increased with increasing silt, clay and moisture content. On fillslopes, MWD increased with in-creasing rock fragment cover, plant cover, litter cover, organic matter and sand. There was a strong negative correlation between fillslope erodibility and organic matter, sand and MWD. There was no significant difference between erodibility of bare soil and soils beneathRubus hyrcanusL. and Philonotis marchica (Hedw.) Brid.  相似文献   
43.
In order to investigate the effect of anesthesia on serum parameters, Beluga, Huso huso (L.) were blood-sampled immediately without anesthesia (control) or subjected to following anesthesia procedure: 40, 120, and 240 s exposure to 3,000, 700, and 500 mg l−1 clove solution, respectively. Blood samples were collected after these periods, when fish were immobile and reached stage 4 anesthesia. Results showed that cortisol and glucose levels were significantly high in 700 and 500 but not 3,000 mg l−1 group compared to control. Serum lactate levels were significantly high in 500 mg l−1 group compared to control group. Lactate levels were not significantly differed between control, 3,000, and 700 mg l−1 groups. There were no significant differences in serum levels of cholesterol, total protein, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, Na+, Cl, K+, and Ca2+. Results suggest that rapid anesthesia with higher dose is better than slow anesthesia with lower dose for blood sampling in Beluga.  相似文献   
44.
The effects of zinc–methionine (Zn‐Met) supplementation on growth, blood metabolites and gastrointestinal development were investigated in two experiments with sheep. The objective of Experiment 1 was to determine the effects of Zn‐Met supplementation on hormones and metabolites involved in growth and energy balance regulation, while Experiment 2 aimed to determine the effects of Zn‐Met on feed intake, body weight, gastrointestinal development and liver glycogen concentration in lamb. The animals were assigned to groups with different concentrations of dietary Zn‐Met (0, 0.4, 0.8 and 1.2 g/day) in both experiments. In Experiment 1, feeding different doses of Zn‐Met increased plasma insulin‐like growth factor 1 (IGF‐1) concentration, but it linearly decreased plasma growth hormone (GH). No differences were observed in blood cortisol, insulin and glucose concentrations among the treatments. In Experiment 2, addition of Zn‐Met to the diets did not lead to changes in the body weights of the lambs. Both average daily gain and dry matter intake (DMI) increased linearly with increasing concentrations of dietary Zn‐Met. Lambs receiving Zn‐Met showed higher liver glycogen concentrations than the control. While significant increases were observed in the villus height and crypt depth in the duodenum and jejunum as a result of Zn‐Met supplementation, no change was detected in blood glucose concentrations (p > 0.05). Our findings suggest that dietary Zn‐Met may improve growth, energy balance and gastrointestinal development in sheep.  相似文献   
45.
In this study, various concentrations of polyethylene terephthalate (PET) polymeric solution were investigated to produce hollow nanofiber yarn. First, the electrospining apparatus was designed in a way that to put PVA multifilament in the core and to twist PET nanofibers onto multifilament yarn as a sheath simultaneously, followed by dissolving PVA yarn in hot water, PET hollow nanofiber yarn was produced. In this survey, it has been observed that the average thickness of sheath increased by increasing concentrations of PET polymeric solution. Results showed that maximum efficiency of extracting the PVA multifilament from the hollow yarn under certain conditions (concentration of 18 % (w/v) of PET, applied voltage of 10 kV, and flow rate of 0.0526 ml/h) was more than 85 %. The mechanical and physical properties of PET hollow yarns were investigated and indicated that the hollow nanofiber yarns at concentration of 30 % and 18 % polymeric solution had the lowest strength and the highest regain moisture, respectively.  相似文献   
46.
A proper collector is designed and examined in electrospinning process to produce electrospun nanofibers with favored mechanical propertied. The quality of product was controlled by changing and optimizing the process variables, namely electrospinning time, gap distance, and collector rotating speed in a manner that well-aligned yarns were fabricated from polyacrylonitrile (PAN) dilute solutions. It was found that the tensile characteristics of fabricated yarns are greatly dependent on the process variables. Incorporation of multi-walled carbon nanotubes (MWCNTs) into the polymer solution revealed improvement to the yarn strength because of enhancement in alignment of the filaments. The state of fiber alignment and dispersion of MWCNTs were detected by means of scanning electron microscopy. It was illustrated that combination of nanofibers and microfibers gives PAN/MWCNTs composite nanofibers with high surface area and high porosity to satisfy sophisticated users.  相似文献   
47.
The supercritical fluid extraction (SFE) of the aerial parts of Perovskia atriplicifolia Benth. was studied. The effect of different parameters such as pressure, temperature, modifier identity, and modifier volume on the SFE of the plant was investigated. The extracts were analyzed by GC and GC-MS and compared with the essential oil obtained from P. atriplicifolia Benth by steam distillation. The supercritical extracts and the steam-distilled products had very different compositions. The main constituents of the oil obtained by steam distillation were 1,8-cineole, limonene, camphor, beta-caryophyllene, alpha-pinene, camphene, and alpha-humulene. On the other hand, the major components of SFE extracts were 1,8-cineole, limonene, camphor, beta-caryophyllene, gamma-cadinene, alpha-pinene, and alpha-terpinyl acetate. The results showed that increasing the temperature from 35 to 65 degrees C (at a constant pressure of 100 atm) drastically reduced the number of extracted components. Also, the number of extracted constituents and the percent of main analytes increased when lower pressures were used. Using different modifiers (e.g., methanol, ethanol, dichloromethane, and hexane) for the extraction of the plant at low pressure (100 atm) and temperature (35 degrees C) showed that hexane was more selective than the other modifiers.  相似文献   
48.
ABSTRACT

A pot experiment was conducted in a greenhouse on a calcareous soil (fine, mixed, mesic, Fluventic Haploxerepts) to study the interaction of zinc (Zn) and boron (B) on the growth and nutrient concentration of corn (Zea mays L.). Treatments consisted of a factorial arrangement of seven levels of B (0, 2.5, 5, 10, 20, 40, and 80 mg kg? 1as boric acid), two sources of Zn [zinc sulfate (ZnSO4 · 7H2O) and zinc oxide (ZnO)], and three levels of Zn (0, 5, and 10 mg kg? 1) in a completely randomized design with three replications. Plants were grown for 70 d in 1.6 L plastic containers. Applied Zn significantly increased plant height and dry matter yield (DMY) of corn. Source of Zn did not significantly affect growth or nutrient concentration. High levels of B decreased plant height and DMY. There was a significant B × Zn interaction on plant growth and tissue nutrient concentration which were rate dependent. In general, the effect of B × Zn interaction was antagonistic on nutrient concentration and synergistic on growth. It is recommended that the plants be supplied with adequate Zn when corn is grown in high B soils, especially when availability of Zn is low.  相似文献   
49.
The purpose of this study was to determine the factors influencing consumers' attitudes toward organic agricultural products. The study is correlational research. Results of regression analysis indicated that the variables of health awareness, knowledge of organic products, and consumers' motivations and age explained 32% of the changes in attitudes about organic products. The authors therefore recommend educational initiatives to increase knowledge and awareness and influence attitudes and consumption habits.  相似文献   
50.
Seeds of many woody plant species have one of several types of dormancy. They do not germinate unless specific environmental signals are in place or events occur. This study was conducted to evaluate the effects of scarification treatments on seed dormancy and germination of Acacia nilotica (L.) Willd. ex Del., Prosopis juliflora (Sw.) DC. and Dodonaea viscosa (L.) Jacq. The following treatments were applied: T1, untreated seed (control); T2, sulphuric acid (97%) for 45 min; T3, boiling water for 5 min. The seeds were cultured on a Murashige and Skoog (MS) medium after sterilization. The responses of seeds to treatments were compared with each other and with the control treatment. Germination was observed daily for a 30-day period. Results indicated positive responses to treatments, while impermeable seed coats may be responsible for low germination rates in intact seeds as seen experimentally in the untreated control. The highest germination was obtained for P. juliflora and D. viscosa acid-scarified seeds (80.8%-90.8%) and for scarified seeds of A. nilotica (50.2%) boiled in water. The germination indices, i.e., final germination percentage (FG), mean daily germination (MDG) and germination rate (GR), were significantly affected by treatments and species (p<0.01).  相似文献   
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