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311.
A study was conducted to investigate the effects of dietary oligofructose (1, 2 and 3%) on the blood profiles of beluga (Huso huso) juveniles (18.77 ± 0.76 g) compared to fish fed an un-supplemented diet. After 7 weeks of feeding on the experimental diets, haematological parameters, metabolic products (cholesterol, glucose and total protein) and serum enzymes (lactate dehydrogenase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase) were measured. Compared to the control group (0% oligofructose), dietary oligofructose had no effect on red blood cell counts (RBC), mean corpuscular volume (MCV), mean cellular haemoglobin (MCH) or mean cell haemoglobin concentration (MCHC) (P > 0.05). However, haemoglobin (Hb) concentration, leucocyte (WBC) levels and the proportion of lymphocytes were significantly higher (P > 0.05) in the 2% oligofructose fed fish than in the 3% oligofructose fed fish. Additionally, haematocrit (Hct) values (P = 0.049) and the proportion of lymphocytes (P ≤ 0.01) were significantly higher in the 2% oligofructose group than in the control group. Although serum glucose and total protein remained unaffected, serum cholesterol was significantly lower in the 2% oligofructose group than in the control and 3% oligofructose group (P < 0.05). The results of the present study showed that oligofructose had no significant effects on serum lactate dehydrogenase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. These results indicate that fish blood profiles could be affected by prebiotics, which should be taken into account in future studies.  相似文献   
312.
The aim of this study was to determine the biochemical and histopathological effects of indoxacarb on an economic fish species Cyprinus carpio. The fish were divided into four triplicated groups exposed to either of 0% (control), 5% (0.75 mg/L), 10% (1.5 mg/L) or 20% (3 mg/L) of the pesticide LC50. Blood sampling was performed after 7, 14 and 21 days exposure. There were no changes in blood calcium levels at any times. In the indoxacarb‐treated fish, chloride levels decreased at the first and increased at the second sampling compared to the control. In 3 mg/L treatment, phosphorus increased significantly after 7 days compared to the control. Plasma glucose levels decreased significantly at the 7th and 14th days sampling; however, it increased at the 21st day. After 7 days, creatinine level in 3 mg/L treatment was significantly lower than the control; however, the creatinine levels of indoxacarb treatments were higher than the control at the 21st day. The indoxacarb‐treated fish had higher plasma urea levels compared to the control at the 7th day. At the 21st day, plasma urea level at 3 mg/L was significantly lower than the control treatment. Edema, Lamellar curling, hyperplasia, lamellar fusion and hyperaemia were observed in the indoxacarb‐treated fish gill. Tubular necrosis, hematopoietic necrosis, melanomacrophage aggregates, Bowman's capsule edema, glomerulus degeneration and hyperaemia were observed in the indoxacarb‐treated fish kidney. Generally, sublethal concentrations of indoxacarb cause stress, hydromineral imbalance, metabolism alteration and gill and kidney damages in common carp.  相似文献   
313.
We investigated the altitudinal variation of Carpinus betulus L. in the Hyrcanian forest using leaf macro-morphological and micro-morphological traits. We collected a total of 1600 leaves from two locations. In each location, we sampled six populations along an altitudinal gradient ranging from 100 m to 1,150 m. We found that trees in the higher elevations have smaller leaf lamina than those in the lower elevations. In contrast, leaf mass per area was high at low altitudes and increased newly at the higher ones. Stomatal dimension was negatively correlated with elevation, while stomatal density was positively correlated with elevation. We also found that two transects showed the same plasticity trend. Leaf area showed the highest plasticity, while the number of veins showed the lowest plasticity. This study shows that altitude, and related temperature and rainfall, represents an important driving force in Carpinus betulus leaf morphological variation. Moreover, our results suggest that leaf area, leaf mass per area and stomatal density could influence the species responses to different ecological conditions.  相似文献   
314.
Two-spotted spider mite (TSSM) and onion thrips are serious pests of potatoes in the Ardabil region (Iran). In the present study, anthocorid species were identified in potato fields of this region during 2006 and 2007. The results of the abundance study indicate that Orius niger (Wolff) and O. minutus (Linnaeus) are major predators of these pests in potato fields. The life table parameters of these predators were compared when they were fed 2nd instar larvae of onion thrips or female TSSM on potato leaves. In these experiments, O. niger had a lower nymphal mortality, longer oviposition period, higher net reproductive rate (R 0), and higher intrinsic rate of natural increase (r m ) when fed thrips instead of mites. O. minutus feeding on mites compare to thrips had a lower nymphal mortality, longer oviposition period, higher net reproductive rate, and higher intrinsic rate of natural increase. Based on these results, it can be concluded that these predators could be useful as biological agents in potato fields.  相似文献   
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317.
Nineteen agrochemical traits of 20 almond inter-specific backcrosses progenies were evaluated and compared for three consequence years to find out their phenotypic diversity and determine the relationships of fruit quality traits in almond × peach backcrosses breeding progenies. The variation was observed for traits of phenology parameters (blooming time, ripening time), Physical parameters (fruit weight, width, height, shape, thickness, skin pubescences, colour and flower type), chemical parameters (total sugar content, soluble solids content and acidity) and sensory parameters (attractiveness, taste, and flavor) and yield. Many fruit characteristics that are important to breeders are present in this collection. A high variability was found in the evaluated almond progenies and significant differences were found among them in all studied quality attributes. Year-by-year variations were observed for majority of traits. A significant correlation was found among the fruit height, fruit width, skin pubescences and yield. Fruit height showed a significant positive correlation with fruit weight and fruit thickness and some other traits and a negative correlation with the titratable acidity, skin pubescences and fruit flavour. A high negative correlation was found between the fruit weight and titratable acidity (?0.8). Low coefficients were got between the flower colour and skin pubescences. In addition, principal component analysis it possible to established similar groups of genotypes depending on their quality characteristics and to study relationships among pomological traits in almond progenies evaluated.  相似文献   
318.
In order to investigate the changes in chlorophyll fluorescence, chlorophyll, relative water content (RWC) and forage yield of corn and sorghum under various irrigation regimes and combination treatments of barley residue, zeolite and superabsorbent polymer, an experiment was conducted over 2 years in Kerman, Iran. A randomized complete block design arranged in a factorial split was used with three replications. Two irrigation regimes of normal and drought stress based on 70 and 140 mm cumulative pan evaporation, respectively, and two plant species (corn and sorghum) as factorial combinations were compared in the main plots. Five treatments, (1) 10 t ha?1 zeolite + 4.5 t ha?1 residue, (2) 60 kg ha?1 superabsorbent + 4.5 t ha?1 residue, (3) 5 t ha?1 zeolite + 30 kg ha?1 superabsorbent + 4.5 t ha?1 residue, (4) 4.5 t ha?1 residue and (5) – control, were compared in subplots. In both plants, forage yield, potential quantum yield (Fv/Fm), chlorophyll a, total chlorophyll and carotenoid contents decreased significantly under drought stress. Chlorophyll a content, SPAD index and Fv/Fm were higher in corn than in sorghum, but RWC was higher in sorghum. Corn produced higher forage yield (62.8 t ha?1) than sorghum (49.3 t ha?1). The application of 10 t ha?1 zeolite with 4.5 t ha?1 residue increased most traits more than any of the other treatments, but the superabsorbent had no significant effect on the studied traits.  相似文献   
319.
Knowing the concentrations of the nutrient elements in soils is important due to their toxic effect on humans and the environment. The aims of this study were to assess the effects of water quality, depths, and distances of lateral installation on soil chemical properties during turfgrass cultivation. A field experiment was conducted using a Split-Split-Plot design based on the randomized complete block (RCB) design with two treatments (well water and wastewater) and eight sub-treatments (45 and 60 cm distance of the laterals and 15, 20, 25, and 30 cm depths of laterals) in three replicates on a sandy loam soil, in Shahrekord, Iran. Soil samples were collected from 0 to 30 and 30 to 60 cm depth for measuring nitrate (NO3?), electrical conductivity (EC), and pH at the end of the experiment. During the experiment, fecal coliform was also measured at the soil surface. Results indicated that by increasing lateral distance, NO3? level increased in both layers. With installing laterals in deeper levels, NO3? concentration decreased at the beginning, then increased in the first layer, whereas in the second layer, NO3? concentration decreased. In addition, installing laterals in deeper depth caused an increase in soil EC in the top layer, but a decrease in the lower layer. However, the results showed that there was no significant effect of the treatments (well water and wastewater) and the sub-treatments (distance and depths of laterals) on soil pH. The results also show that with increasing laterals depth, fecal coliform level decreased at the soil surface.  相似文献   
320.
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