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161.
This study was carried out to investigate the effects of bamboo charcoal and bamboo vinegar as alternatives of antibiotics in the diet of fattening pigs and their influence on growth performance, immune responses and fecal microflora populations. Crossed pigs (n = 144, 79 kg body weight) were divided into 12 heads per pen, four diets and three replications. The basal diet (negative control: NC) was supplemented with 0.3% antibiotics (positive control: PC), 0.3% bamboo charcoal (BC) and 0.3% bamboo vinegar (BV). Average daily weight gain and feed efficiency were higher (P < 0.05) in PC, BC and BV. The concentration of lactate dehydrogenase and cortisol were lower (P < 0.05), but the concentration of immunoglobulin G (IgG) and IgA were higher (P < 0.05) in PC, BC and BV. Counts of coliform bacteria and Salmonella spp. were lower (P < 0.05), while the counts of fecal anaerobic total bacteria and lactic acid bacteria were higher (P < 0.05) in PC, BC and BV. A reasonable inclusion of bamboo charcoal or bamboo vinegar as antibiotics in the diet of fattening pigs leads to a better growth performance, immune responses and fecal microflora populations. The results of the present study suggest that bamboo charcoal or bamboo vinegar could be a potential additives in animal production as an alternative to antibiotics.  相似文献   
162.
Leaf leachate of Anthemis cotula inhibits seed germination of the commonly cultivated field crops in Kashmir valley. Among the four indices of germination (GT, S, AS, CRG), S (speed of germination) and AS (speed of accumulated germination) are sensitive enough to establish the allelopathic activity of the leaf leachate. Inhibition of seed/grain germination of the field crops showed a species‐specific and dose‐dependent response with highest inhibition occurring at 5000 ppm concentration. Brassica campestris seeds are most sensitive, whereas those of Vigna radiata are least sensitive. Interestingly, achene germination of A. cotula is promoted by its own leachate at low concentrations and inhibited at high concentrations.  相似文献   
163.
164.
Remote sensing is currently a tremendous asset in controlling and monitoring soil salinity. Moderate resolution imaging spectroradiometer (MODIS) images can be obtained daily, are free, offer more opportunities to acquire cloud-free images and may be preferred over high-resolution spatial data. The main objective of this study was to evaluate the capability of MODIS imagery to assess soil properties when coupled with field soil sampling. The study area was ~95,000 ha, located in the south-east of Fars Province, Iran. In total, 240 soil samples were selected from 60 georeferenced soil pits, following a stratified random sampling approach. Sixteen spectral indices were calculated from a nadir-viewed MODIS scene to establish statistical correlation models between measured soil properties and MODIS band values. A precise map of the soil properties was produced using geostatistical techniques. A paired-sample t-test indicates that there are no significant differences between values estimated using MODIS data statistical modeling and laboratory-measured soil properties of samples collected through fieldwork. The results also indicate that image transformation (salinity index (SI) to radiance) reduces estimation errors and increases both model efficiency and the R 2 of the models. The results also indicate that MODIS imagery provides useful information on soil properties.  相似文献   
165.
Field experiments were conducted on rainfed wheat and mungbean for two consecutive seasons on a Udic Ustocrept to evaluate the effect of tillage techniques, fertilization, and weeding on crop yields and nutrient uptake. Tillage techniques were conventional, zero, and deep tillage. Fertilizer treatments consisted of a control, nitrogen (N) and phosphorus (P) fertilizer, and farmyard manure plus fertilizer. Grain yield of wheat (Triticum aestivum L.) was 2,404 kg/ha under conventional tillage, 2,008 kg/ha under zero tillage, and 2,839 kg/ha under deep tillage. Total dry matter of wheat was 7,612 kg/ha under deep tillage, 6,671 kg/ha under conventional tillage, and 6,016 kg/ha under zero tillage. Fertilizer application increased wheat grain yield by 112% and total dry matter by 150% over the control. Weed biomass of wheat was 57% greater under zero tillage than under conventional tillage. Mungbean (Vigna radiata L.) grain yield was 371 kg/ha under conventional tillage, 248 kg/ha under zero tillage, and 367 kg/ha under deep tillage. Mungbean total dry matter yield was 2,018 kg/ha under deep tillage, 1,814 kg/ha under conventional, and 1,143 kg/ha under zero tillage. Dry weed biomass in mungbean was 38% greater under zero tillage and 6% lesser under deep tillage than that of conventional tillage. Nitrogen and P uptake by weeds was greater under zero tillage compared with conventional and deep tillage.  相似文献   
166.
A five-year cotton–wheat rotation field experiment was conducted on two alkaline-calcareous soils, i.e., Awagat (coarse loamy) and Shahpur (fine silty), to investigate the impact of integrated nutrient and crop residue management on soil and crop productivity. Apparent nitrogen (N) balances were developed. Minimum five-year mean yield (Mg ha?1), obtained with Farmers’ Fertilizer Use (FFU) treatment was: cotton – Awagat, 2.19; Shahpur, 2.45; wheat – Awagat, 3.03; Shahpur, 3.94. With Balance Nutrient Management (BNM), yields increased (P ≤ 0.05) for cotton, 24% in Awagat and 18% in Shahpur soil; and wheat, 37% in Awagat and 24% in Shahpur soil. Maximum crop yields were obtained with Integrated Nutrient Management (INM), i.e., 3–5% higher than with BNM. Crop residue recycling increased the yields further, cotton by 2?7% and wheat by 2–10%. All nutrient management treatments, except for FFU without crop residue recycling, resulted in positive apparent N balances. INM improved SOM and NO3-N, contents.  相似文献   
167.
Two sets of column (70 cm)-leaching experiments were carried out by using pyritic marine sediments of Kojima lake (Okayama, Japan) to evaluate the influence of soil microorganisms (SMO), duration of oxidation, intensity of rainfall, and groundwater level on the changes in soil pH and dynamics of associated elements. The soil contained 6.5 g kg-1 pyrite, 43 g kg-1 organic carbon, and had a pH value of 8.0 determined by the sticky point method. The pH of the non-sterile soils (with SMO=set I) showed an acidic range (pH <6.5) after 2 weeks of incubation. A pronounced decrease of the pH (3–4) was detected during the 32-week period of incubation, while a more alkaline range of pH (>8.5) was recorded at the lower depths (40–50 cm) with the passage of time in most of the soils initially sterilized (without SMO=set II). When the water (25±2% air v.) content was about 200%, the pH of the non-sterile soils was less than 6 after 16 weeks of incubation, while for the same water content at 32 weeks after incubation, the pH of the soils was about 1 unit lower than that of the 16 weeks after incubation. However, the pH in sterilized soils was less than 6 after 32 weeks of incubation for a water content of about 150% (40±2% air v.), whereas, at such (40±2% air v.) levels of water or oxygenation, the pH of the soils decreased to about 3 in all the treatments with SMO. Application of rainfall and changes in the groundwater significantly (p≤0.01) enhanced the development of acidity in the top soils (0–15 cm) through leaching losses of Ca2+ and Mg2+, and led to a substantial increase of the amounts of water-extractable Fe3+ and A13+, indicating that the soils may have become permanently acidic through leaching.  相似文献   
168.
Caprine arthritis encephalitis (CAE) is a chronic debilitating disease of goats caused by a lentivirus responsible for economic losses as a result of a drop in milk production and weight loss. The objective of the study was to determine if indigenous goats from five different regions in the Sultanate of Oman exhibit serological evidence of exposure to CAEV using a competitive-inhibition ELISA technique. Blood samples were collected from slaughtered goats (N = 1,110) and from the National Serum Bank (n = 528). In total, 83 (5.1%) of screened samples were classed as seropositive. The results provide the first serological evidence for the presence of CAEV in Oman.  相似文献   
169.
Summary Two Sonchus asper (spiny annual sow-thistle) biotypes, suspected of being resistant to the sulfonylurea herbicide metsulfuron-methyl, were collected in 1996 from two barley ( Hordeum vulgare ) fields in central Alberta, Canada. Both fields had received at least six applications of acetolactate synthase (ALS)-inhibiting herbicide(s). The responses of the two resistant (R) biotypes and two susceptible (S) biotypes to several sulfonylurea herbicides, and to herbicides and herbicide mixtures with other mechanisms of action, were compared. Both R biotypes were highly resistant to all sulfonylurea herbicides, but their control with other herbicides and mixtures was effective and comparable to that of the S biotypes. ALS extracted from an R biotype was about 440 times more resistant to metsulfuron-methyl than that of an S biotype, indicating that resistance was conferred by an ALS enzyme that was less sensitive to inhibition by the herbicide. Competitiveness and seed production of S. asper varied among biotypes, but the differences were probably the result of ecotype differences rather than resistance or susceptibility to sulfonylurea herbicides. This is the first reported occurrence of target site-based S. asper resistance to ALS-inhibiting herbicides.  相似文献   
170.
The isolation and NMR spectral data of epifriedelanol from Vitis trifolia are reported. It demonstrated antitumor activity in a potato disc bioassay.  相似文献   
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