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41.
A 6‐week feeding trial was conducted for determining the effects of dietary essential amino acids (EAA) deficiencies on growth performance and non‐specific immune responses in silvery‐black porgy juveniles (4.7 ± 0.1 g initial weight). Eleven isoproteic (ca. 47%) diets were formulated including a control diet containing the optimum quantity of EAA, and ten EAA‐deficient diets. All diets contained 36% fish meal and 18.5% crystalline EAA and non‐essential amino acids (NEAA) as the main source of dietary proteins. All the EAA and NEAA incorporated in the crystalline amino acids mixture of the control diet simulated the amino acids profile of the fish meal. The other 10 EAA‐deficient diets were formulated by the deletion of each of the 10 EAA (crystalline form) from the control diet and replaced by a mixture of NEAA for the adjustment of dietary nitrogen contents. At the end of the experiment, fish fed with threonine‐deficient diet showed the lowest survival rate (< .05), whereas growth performance decreased in fish fed all EAA‐deficient diets, although the reduction in body growth varied depending on the EAA considered. Plasma total protein decreased in all experimental groups except for fish fed the phenylalanine‐deficient diet. Fish fed with arginine‐ and lysine‐deficient diets had the lowest plasma C3, C4, lysozyme, total immunoglobulin and total superoxide dismutase activity (< .05). Present results indicated that lysine, methionine and threonine were the most limiting EAA in terms of growth performance; however, arginine, threonine and lysine were the most limiting EAA for innate immunity responses in silvery‐black porgy juveniles.  相似文献   
42.
Abstract

In order to reduce the damage caused by the late-season drought stress of canola, a factorial split-plot experiment was performed based on the randomized complete blocks design with three replications in Karaj, Iran. The treatments were Potassium sulfate in two levels, including application and non-application of potassium sulfate, irrigation at three levels including normal irrigation (control), restricted irrigation from the flowering and pod formation stage, as factorial were in main plots and winter canola cultivars including Opera, L72, KR1, GKH3705, GKH0224 were in subplots. The simple effect of irrigation and potassium sulfate on all of the studied traits and the simple effect of cultivar on all traits except chlorophyll b were significant. The interaction effect of irrigation?×?cultivar on soluble carbohydrate, stomatal resistance, proline content, chlorophyll a and total chlorophyll content was significant. The interaction effect of irrigation?×?potassium sulfate on the amount of soluble carbohydrates, stomatal resistance and proline content of leaves was significant. In irrigation interruption from the pod formation stage, the promising line of L72, and in irrigation interruption from the flowering stage, the Neptune cultivar exhibited the most positive effect of potassium application on the studied traits. As a result, the application of potassium sulfate in addition to the L72 and Neptune cultivars is recommended in areas similar to the tested area encountering the late-season drought stress.  相似文献   
43.
Tropical Animal Health and Production - The present experiment was conducted to investigate the effect of using an extract of Ascophyllum nodosum algae (Tasco®, AN) on feed digestibility and...  相似文献   
44.
To understand epidemiology of Bacillus anthracis in Iran, the morphological, biochemical, and virulence specifications of 32 B. anthracis isolates, collected from human, sheep, cattle, goat, and environmental specimens obtained from throughout Iran were examined by conventional and molecular approaches. B. anthracis isolates were characterized in multiple ways: (1) capsule formation both on bicarbonate agar and in defibrinated horse blood, (2) motility of vegetative forms, (3) hemolysis on 5% sheep blood agar, (4) penicillin G susceptibility, (5) lecithinase production on egg yolk agar, (6) gelatin hydrolysis, (7) ability to develop “string of pearls” on tryptose agar, and (8) capability to develop mucoid colonies in presence of CO2 were assessed. In addition, biochemical properties such as indole, methyl red, catalase, citrate utilization, and finally nitrate reduction tests were used. All the tested isolates produced identical morphological and biochemical patterns with those of the vaccine strain B. anthracis 34F2 Sterne. In order to assess potential virulence of isolates at genomic level, PCR protocols assaying for the pXO1 and pXO2 loci were employed. The intriguing high level of phenotypic similarity between Iranian isolates of B. anthracis and the 34F2 Sterne strain deserves further studies at genomic level.  相似文献   
45.
The present study aimed at assessing the effects of addition of thymol [0 (T0), 2.5 mg/L (T2.5), 5 mg/L (T5) and 10 mg/L (T10)] to water on biochemical and antioxidant responses of common carp, Cyprinus carpio, during 3-h transportation. The lowest dissolved oxygen and ammonia levels after transportation were related to T2.5 and T5 treatments respectively. T5 treatment exhibited lower cortisol/glucose responses after transportation and 24 h after that, whereas T2.5 and T10 exhibited elevations in these parameters at the same times. Hyperammonaemia and hyperchloraemia were observed in T2.5 treatment immediately after transportation, but such changes were observed in all treatments, 24 h after transportation. Addition of 10 mg/L thymol to water prevented uraemia after transportation, but all thymol-treated fish exhibited uraemia, 24 h after transportation. Thymol treatment failed to mitigate lactate elevation immediately after transportation; nevertheless, T2.5 and T10 had, respectively, the lowest and highest lactate levels, 24 h after transportation. T5 treatment inhibited alteration in superoxide dismutase activity, immediately after transportation, and T10 exhibited a similar effect, 24 h after transportation. Addition of 2.5 mg/L thymol to water significantly increased catalase activity immediately after transportation, but such a response was observed in all treatments, 24 h after transportation. T2.5 and T10 exhibited higher malondialdehyde levels than T0 immediately after transportation, but such a response was observed in all thymol-treated fish, 24 h after transportation. In conclusion, addition of 5 mg/L thymol is beneficial in reducing water ammonia concentration and stress in carp during transportation.  相似文献   
46.
The California Simulation of Evapotranspiration of Applied Water (Cal-SIMETAW) model is a new tool developed by the California Department of Water Resources and the University of California, Davis to perform daily soil water balance and determine crop evapotranspiration (ET c ), evapotranspiration of applied water (ET aw ), and applied water (AW) for use in California water resources planning. ET aw is a seasonal estimate of the water needed to irrigate a crop assuming 100% irrigation efficiency. The model accounts for soils, crop coefficients, rooting depths, seepage, etc. that influence crop water balance. It provides spatial soil and climate information and it uses historical crop and land-use category information to provide seasonal water balance estimates by combinations of detailed analysis unit and county (DAU/County) over California. The result is a large data base of ET c and ET aw that will be used to update information in the new California Water Plan (CWP). The application uses the daily climate data, i.e., maximum (T x ) and minimum (T n ) temperature and precipitation (P cp ), which were derived from monthly USDA-NRCS PRISM data (PRISM Group 2011) and daily US National Climate Data Center (NCDC) climate station data to cover California on a 4 km×4 km change grid spacing. The application uses daily weather data to determine reference evapotranspiration (ET o ), using the Hargreaves-Samani (HS) equation (Hargreaves and Samani 1982, 1985). Because the HS equation is based on temperature only, ET o from the HS equation were compared with CIMIS ET o at the same locations using available CIMIS data to determine correction factors to estimate CIMIS ET o from the HS ET o to account for spatial climate differences. Cal-SIMETAW also employs near real-time reference evapotranspiration (ET o ) information from Spatial CIMIS, which is a model that combines weather station data and remote sensing to provide a grid of ET o information. A second database containing the available soil water holding capacity and soil depth information for all of California was also developed from the USDA-NRCS SSURGO database. The Cal-SIMETAW program also has the ability to generate daily weather data from monthly mean values for use in studying climate change scenarios and their possible impacts on water demand in the state. The key objective of this project is to improve the accuracy of water use estimates for the California Water Plan (CWP), which provides a comprehensive report on water supply, demand, and management in California. In this paper, we will discuss the model and how it determines ET aw for use in water resources planning.  相似文献   
47.
The mechanical properties of thin spunbond tissues depend on the distribution of fibers in tissues structure. The optimum fiber distribution leads to the fiber mass uniformity spreading in the tissue structure. The present research defines an optimum model of fiber distribution in the tissue structure by using genetic algorithm. To find the applicability of the presented optimization method, some samples have been prepared from Polypropylene fibers (1.5 Den). The mechanical tests have been performed on tissue samples. The results confirmed that the developed model using genetic algorithm can be applied as a reliable method to determine optimum fiber distribution strongly.  相似文献   
48.
The aim of this study was to determine the gill histopathological characteristics of Caspian roach (Rutilus rutilus caspicus) fingerlings exposed to different concentrations of potassium permanganate (PM) and formalin (FO). The fish were exposed to different PM and FO concentrations over different periods: 1 ppm PM for 24 h (1‐P24), 2 ppm PM for 24 h (2‐P24), 5 ppm PM for 0.5 h (5‐P0.5), 10 ppm PM for 0.5 h (10‐P0.5), 10 ppm FO for 24 h (10‐F24), 20 ppm FO for 24 h (20‐F24), 40 ppm FO for 0.5 h (40‐F0.5) and 80 ppm FO for 0.5 h (80‐F0.5). After exposure, gill samples were collected for histological examination. The most frequent gill histopathological symptoms were hyperplasia and epithelial lifting. The order of the gill injury index (Ig.i) among the treatments was as follow: 1‐P24, 2‐P24 < 5‐P0.5, 40‐F0.5 < 10‐F24 < 10‐P0.5, 20‐F24, 80‐F0.5. Comparing the two agents, it is concluded that there is no significant difference in the gill damages between the agents during the short‐bath treatments. However, PM causes less pathological symptoms than FO during the long‐bath treatments. Comparing the bath durations, the agents showed different behaviours. PM‐treated fish showed significantly lower gill damage during the long‐bath compared to the short‐bath treatment; whereas, pathological symptoms of FO‐treated fish was dose‐dependent for each exposure period, separately. Overall, exposure of Caspian roach to PM, at the concentrations recommended for long bath, resulted in milder gill damages compared to FO.  相似文献   
49.
The physiological ionoregulatory, metabolic and immune responses of Persian sturgeon, Acipenser persicus, to acute stress were investigated. Water levels were lowered to the fish dorsal scutes, and fish were blood‐sampled before stress (pre‐stress), and 0, 6, 24 and 72 h after stress. Results showed that serum cortisol rapidly increased after stress, returning to initial levels at 24 h. Serum glucose significantly increased at 6 h, declining to the pre‐stress levels at 72 h. Serum triglyceride and cholesterol showed significant decreases at 0 h, then increasing to higher than the initial levels at 72 h. Serum T3 and T4 significantly decreased at 0 h and recovered at 72 h. Serum chloride levels showed no significant changes while serum calcium showed a significant increase at 0 h and a further increase until 72 h poststress. Serum total protein and alternative complement activity showed a significant initial decrease and recovery at 24 h with further increase at 72 h. Serum lysozyme activity increased significantly at 24 and 72 h after stress. Serum total immunoglobulin significantly increased at 0 h and peaked at 24 h. This is the first work showing thyroid hormone and immunological responses in Persian sturgeon subjected to stress, and the results show that this species follows a classical hormonal and energetic stress response, although, in the low range among the sturgeons. Although transient and moderate, confinement stress can induce significant changes in the innate immune response.  相似文献   
50.
Potassium permanganate (PM) is a therapeutic agent in aquaculture with strong oxidant properties. In this study, the effects of potassium permanganate treatment (PMT) on stress response and blood biochemistry were investigated in goldfish Carassius auratus. Two triplicate groups of fish were exposed to either 10 mg L?1 PM or clean water, over 30 min. Blood samples were collected at 0 and 0.5 h after exposure as well as 3 and 24 h. PMT caused significant increase in serum cortisol and glucose levels, 0.5 h post exposure, which stayed elevated until 24 h. Sodium decreased after exposure and did not return to initial levels. Chloride decreased at 0.5 and 3 h, but returned to initial levels at 24 h. Calcium decreased at 0.5 h and returned to initial at 3 h, but significantly increased at 24 h. Total protein, albumin and globulin levels increased at 3 h and stayed elevated until 24 h. Albumin:globulin ratio (A:G) levels decreased at 24 h post exposure. Results indicated that short‐term PMT caused stress response, hydromineral imbalance and possibly change in blood protein profile in goldfish, which lasted until 24 h post treatment.  相似文献   
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