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81.
Antibacterial activity of the essential oil from Ferula gummosa seed   总被引:1,自引:0,他引:1  
Antibacterial activity of Ferula gummosa essential oil was studied against bacterial laboratory ATCC standards using the disk diffusion method. The results showed activity against Gram(+) bacteria and Escherichia coli. Little antibacterial activity was found against Pseudomonas aeruginosa.  相似文献   
82.
83.
Drought is currently one of the most severe abiotic factors limiting agricultural production. The high rates of population growth and global warming are expected to further exacerbate the threat of drought, especially in areas with a semi-arid climate as in the Middle East region. Selecting genotypes for improved drought tolerance has long been of interest for those involved in horticulture. The present research investigated the reaction of seven 10-year-old olive genotypes to drought stress in Dallaho Olive Research Station, Iran. To determine the reaction of genotypes to drought stress, physiological and biochemical characteristics, fruit and oil yield, and water use efficiency were measured. The results showed that different genotypes react differently to drought stress while drought decreased vegetative and reproductive traits such as shoot length and diameter, relative water content of the leaves, Ca and K percentage, and fruit yield. Finally, Dd1 and Bn6 showed the highest oil and fruit yield per hectare and the highest water use efficiency. In addition, Bn3 had a favorable status in most of the measured parameters. So, they can be suggested as the genotypes that are tolerant of drought stress. The results also showed that olive yield and irrigation management can be improved by applying proper irrigation levels and using tolerant genotypes.  相似文献   
84.
Gypsum-bonded particleboard manufactured from agricultural based material   总被引:2,自引:0,他引:2  
Gypsum-bonded particleboard (GBPB) panels were made from various mixtures of particles of bagasse (Saccharum officinarum L.) and wheat straw (Triticum aestivum L.), bonded with different ratios of particle/gypsum. This study examined the feasibility of bagasse and wheat straw particles in the production of GBPB. One-layer experimental GBPBs with a density of 1.05 or 1.20 g.cm-3 were manufactured at different ratios of bagasse/wheat straw, i.e., 100%/0%, 93.75%/6.25%, 87.5%/12.5%, 75%/25%, 50%/50%, 25%/75% and 0%/100% using two particle/ gypsum composite ratios, i.e., 1/2.75 and 1/3.25 by weight. Thickness swelling (TS), water absorption (WA), modulus of rupture (MOR), modulus of elasticity (MOE) and internal bond strength (IB) properties of the boards were evaluated and a statistical analysis was performed in order to examine the possible feasibility of these agricultural residues for use in commercial GBPB manufacturing. We determined that WA of panels decreases as the amount of straw increases to 100% and the LR/G (wood/gypsum) ratio decreases to 1/3.25, whereas the TS of panels decreases as the proportion of straw decreases to 0% and the LR/G ratio increases to 1/2.75. The experimental results also show that the MOR and MOE of panels containing 0%, 6.25% and 12.5% wheat straw with a LR/G ratio of 1/2.75 were higher than those of panels made from 25%-100% wheat straw with a LR/G ratio of 1/2.75, as well as those from all other percentages of straw with a LR/G ratio of 1/3.25. On the other hand, the IB of panels containing more than 12.5% straw with LR/G ratios of 1/2.75 and 1/3.25 were lower than those of panels made from 0-12.5% straw also with both LR/G ratios. Panels consisting of 0%, 6.25% and 12.5% wheat straw with LR/G ratios of 1/2.75 and 1/3.25 met the minimum EN standard requirements of mechanical properties for general purposes. All of the panels containing 0-100% wheat straw with a LR/ G ratio of 1/2.75 or 1/3.25 met the required level of TS for 24-h immersion.  相似文献   
85.
Choosing appropriate plants for urban landscapes is vital to avoid potential financial and environmental losses that may occur if all selection parameters are not taken into account. A methodology has been developed to assist landscape architects, planting designers, and urban horticulturists in the plant selection process. Tehran has been picked as a case study due to its arid and semi-arid climate which poses more challenges in front of an expert. After grouping plants, selection parameters have been defined for each plant group. Plant species were comparatively graded for each parameter by a group of eight specialists. Analytical hierarchy process (AHP) technique and hierarchical cluster analysis have been utilized to find the most adaptable plant species for the area according to the main selection parameters of zone tolerance, urban conditions, esthetics, maintenance, growth characteristics, and specific features. Several new plants were ranked high in the final tables suggesting that the urban landscape of Tehran has a great potential to become more attractive, less allergic, and less costly, as well as consuming less water. Before introducing new plants to the urban environment, they should be experimented on in small numbers for several years to confirm that they will not change the ecology of the whole region through invasion or posing a threat to any local plant species.  相似文献   
86.
1. Decreased semen quality is an underlying contributor to age-related subfertility in broiler breeder roosters. This study investigated the effects of dietary curcumin (derived from turmeric) supplementation as an antioxidant source on semen quality and fertility in broiler breeder roosters.

2. Twenty-eight Ross 308 roosters were randomly allotted to four groups with seven birds in each and were fed a standard diet supplemented with different levels of curcumin at 0 (C0), 10 (C10), 20 (C20) and 30 (C30) mg/bird per day from 48 through to 61 weeks of age. Body weight and semen quality traits were evaluated on a weekly basis and seminal concentrations of malondialdehyde (MDA) as a measure of antioxidation status were quantified at one-week intervals during the first 11 weeks of the trial (48–59 weeks of age). Semen samples from last 2 weeks (60 and 61 weeks of age) were used to artificially inseminate to assess the sperm-egg penetration (SP) in perivitelline membrane and fertility rates.

3. Except for body weight and ejaculate volume, other characteristics, including semen concentration, total sperm production, progressive motility and plasma membrane integrity were linearly improved by the increasing levels of curcumin supplementation (P < 0.01). However, dietary curcumin levels were linearly and quadratically associated with decreased seminal concentration of MDA (P < 0.01 and P < 0.03), percentage of abnormal sperm (P < 0.01 and P < 0.07) and increased plasma membrane functionality (P < 0.01 and P < 0.04), respectively. The SP holes in perivitelline membrane were increased in a linear and quadratic manner in response to increasing levels of curcumin (P < 0.01). Moreover, fertility rate was linearly improved (P < 0.01) as the dosage of curcumin increased, and resulted in 8, 12 and 14% improvements in the birds fed C10, C20 and C30, compared to C0, respectively.

4. In conclusion, the results showed that increasing levels of dietary supplementation of curcumin was associated with beneficial effects on semen quality indices and fertility rate in aged broiler breeder roosters.  相似文献   

87.
Tropical Animal Health and Production - In the present study, 10,116 body weight-age records were measured on 2537 Kermani lambs. The records were collected from Kermani Sheep Breeding Station,...  相似文献   
88.
This study aims to evaluate the effects of substituting increasing concentrations of shredded beet pulp (SBP) for corn silage (CS) on nutrient intake, sorting index, intakes of particle size and nutrients, meal and rumination patterns, and chewing activity of dairy cows. Four multiparous (126 ± 13 day in milk) and 4 primiparous (121 ± 11 day in milk) Holstein cows were used in a 4 × 4 Latin square design experiment with 4 periods of 21 days. Dietary treatments were (DM basis): 16% of dietary DM as CS without SBP (0SBP); 8% CS and 8% SBP (8SBP); 4% CS and 12% SBP (12SBP); and 0% CS and 16% SBP (16SBP). We observed a reduction in the extent of sorting against long particles and medium particles but for fine particles with increasing SBP levels in the diets. The number of eating bouts per day was lesser (8.2%) in cows fed SBP diets compared with 0SBP cows and corresponded with a reduction in eating time per d across treatments. The number of ruminating bouts per day was similar across diets (16.8 bouts/day), but substituting SBP for CS in the diets tended to decrease linearly ruminating bout length (5 min/bout) and tended to increase ruminating bout interval (8 min/day). Eating, ruminating and total chewing time when expressed as minutes per kilogram of forage NDF intake and peNDF > 8 intake increased when SBP was substituted for CS in the diets. Primiparous cows had greater ruminating time (57 m/day) and total chewing time (73 min/day), eating rate (0.01 kg of DM/min) compared with multiparous cows. Also, increasing forage NDF and peNDF>8, >8‐mm DM intakes are effective means of stimulating ruminating and chewing activities. This study showed that SBP could partially replace CS and not affect DM intake, but chewing activity may decrease slightly.  相似文献   
89.
The aim of the experiment was to investigate the replacement value of common bean residues in the diet of finishing lambs as an inexpensive fodder instead of wheat straw or maize silage. Forty Arabi male lambs with average body weight of 18.90 ± 0.6 kg were randomly divided into five treatments with eight replications. The five experimental treatments consisted of control diet, and 50% and 100% replacement of bean residues with wheat straw or 25% and 50% replacement with maize silage in the control diet respectively. Lambs were slaughtered at the end of the experiment to evaluate carcass traits and meat characteristics. Dry matter intake, blood glucose, urea nitrogen, cholesterol and triglyceride concentration were not affected by the experimental treatments. Apparent digestibility of nutrients; total concentration of volatile fatty acids, acetate and butyrate; and total rumen protozoa population were linearly increased by increasing the levels of bean residues, as replacement with wheat straw (p < .05). Replacement of bean residues in control diets instead of wheat straw or maize silage caused a positive linear incremental trend for average daily gain and total weight gain. There was no significant difference in daily gain, final weight and feed conversion ratio among the treatments. Instead of wheat straw or maize silage, replacement bean residues linearly increased chewing, ruminating and eating activities per neutral detergent fibre intake (p < .05). Carcass traits and physicochemical characteristics of meat were not affected by the treatments. It is advisable to use bean residues in the diet of lambs as an alternative to the wheat straw or maize silage, because no adverse effects were observed on rumen fermentation, blood metabolites and performance; moreover, improvement in average daily gain, total weight gain and digestibility of nutrients, and the fact that bean residue is less expensive than wheat straw and maize silage.  相似文献   
90.
The Persian squirrel (Sciurus anomalus) is habitat in the Middle East countries and feed on pine acorns and other seeds. The present study was carried out to investigate the histological and volumetric features of the oesophagus in Persian squirrels. Five adult male Persian squirrels were included in the study. The cervical, thoracic and abdominal oesophagus of all subjects were processed routinely and sectioned in a serial manner. Then, the total volume of the oesophagus and its different layers were estimated using Cavalieri's principle. Histological assessment revealed a non‐keratinized stratified squamous epithelium lining the mucosa. No glands were seen in the lamina propria and submucosa. Lamina muscularis was present as a distinct layer of smooth muscle cells separating the lamina propria from the tunica submucosa. The tunica muscularis consisted of two distinct layers of striated muscle fibres: inner circular and outer longitudinal that was intermingled with few scattered smooth muscle fibres especially in the abdominal region. The thoracic region contained more amount of the lamina muscularis and tunica muscularis in comparison to the cervical or abdominal regions. The obtained results revealed that the histological structure of the Persian squirrel oesophagus has differences and similarities with other rodents and even with other species of squirrel. These findings would be useful to improve the knowledge in the areas of histological structure of the rodent digestive system.  相似文献   
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