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31.
Effects of light intensities on growth, survival, reproductive and life span traits of Artemia urmiana were investigated under laboratory conditions. Nauplii of A. urmiana were hatched and raised in 100 g L?1 at four illuminations including 0, 100, 2000 and 5000 lx with 14:10 (light:dark) photoperiod. Mating pairs of mature animals were randomly isolated and reared continuously under similar conditions. The mode and potential of reproduction as well as adult survival shown by each pair were determined throughout their life span. Results showed that percentages of nauplii survival were significantly ( 0.05) different at 5000 and 0 lx (76.50% compared with 26.25%) respectively. Total number of offspring was highly correlated with the light intensities showing increased numbers at higher light intensities compared with darkness or 100 lx. Reproduction mode was relatively affected by various light intensities. Significant ( 0.05) differences were found both in reproductive period and life span at different illuminations. Maximum and minimum offspring productions per reproductive day were found at 5000 and 100 lx respectively. The relative degree of oviparity increased as the illumination decreased (57.92% compared with 22.65% at 0 and 5000 lx respectively). The optimum light intensities appear to be between 2000 lx and 5000 lx in this study. These findings could probably be useful for mass culture of A. urmiana in indoor or recirculating systems as well as in outdoor systems for intensive cyst and biomass production.  相似文献   
32.
The effects of dietary hydroalcoholic extract of honeybee pollen (HBPE) on growth performance, flesh quality, immunity and stress response were investigated. Two hundred fifty‐five rainbow trout (11.14 ± 1.06 g) were fed five diets containing increasing levels of HBPE: control, 0.25HBPE (0.25 g HBPE/kg), 0.5HBPE (0.5 g HBPE/kg), 1HBPE (1 g HBPE/kg) and 1.5HBPE (1.5 g HBPE/kg). After 56 days, rainbow trout fed the 0.5HBPE and 1HBPE diets displayed significantly higher weight gain (49.58 and 53.25 g) and protein efficiency (2.88 and 2.83) compared to those fed the control diet (4.89 and 2.05), respectively (p < .05). For flesh quality, higher protein content in the whole body of fish fed the 1HBPE (633.3 g/kg) and 1.5HBPE (640.9 g/kg) diets was observed when compared to other groups (p < .05). There were no significant differences in the saturated and monounsaturated fatty acid content. Individuals fed the 1HBPE (234.5 g/kg) and 1.5HBPE (234.7 g/kg) diets exhibited higher levels of n‐3 long‐chain polyunsaturated fatty acids in the muscle than the other groups (p < .05). In terms of the immune system, the serum lysozyme and alternative complement pathway haemolytic activity levels in the 0.5HBPE (47.66 and 148.00 U/ml) and 1HBPE (46.00 and 146.33 U/ml) treatments were higher than the other treatments (p < .05). When Aeromonas hydrophila was exposed to different dosages of HBPE, a higher inhibitory zone resulted from 1,000 and 1,500 mg/ml dosage. The lower levels of plasma cortisol were observed in the 1HBPE and 1.5HBPE groups after the complement stress test. Collectively, the present findings suggest that the 1HBPE diet supported superior growth, flesh quality, immunity and stress response of rainbow trout.  相似文献   
33.
This study was conducted to investigate the effect of different methods of using probiotics Bacillus subtilis and Bacillus licheniformis in soya bean‐based diets on the physiology of beluga (Huso huso) (351 ± 4 g). Five experimental diets were formulated to feed beluga for 10 weeks. The results showed that there was no significant difference in weight gain between control (446 g) and 70%SBM‐SPRAY2 (409 g) treatments. Long‐chain polyunsaturated fatty acids in the muscle of beluga fed control (203.2 g/kg) and 70%SBM‐SPRAY2 (166.4 g/kg) diet did not change statistically. Blood performance as a newly introduced factor in individuals fed dietary control (64.06) and 70%SBM‐SPRAY2 (64.33) had higher value as compared with those fed dietary 70%SBM‐DIET2 (61.90) (p < 0.05). Also, total protein (1.68 g/dl) and RBC (0.74 × 106/mm3) in fish fed 70%SBM were statistically lower than other treatments (p < 0.05). Lysozyme, alternative complement activity and total viable counts in beluga fed dietary probiotics were significantly higher than others. In conclusion, feeding fish with the 70%SBM‐SPRAY2 diet improved fish growth and health.  相似文献   
34.
Agriculture is a major source of nitrogen usage and release to environment. Due to the effect of water movement on solute transport, investigating the effect of different management scenarios of irrigation and drainage could be useful for reducing nitrate loss and environmental pollution. This study is a scientific attempt to assess the ability of HYDRUS-2D model to simulate the effect of subsurface controlled drainage on nitrate loss of paddy fields. So, two physical models with difference in depth of subsurface controlled drainage (40 and 60 cm) were constructed. The tanks were filled with loam silty soil texture and then transplanted rice. 90 kg/ha potassium nitrate fertilizer was added in two stages of rice growth. Mid-season drainage was applied 26 days after transplantation. After 17 days, drains were closed again and applied flooded irrigation with 5-cm water stagnant layer above soil surface. During experiment, nitrate concentration of drain water was measured. HYDRUS-2D was calibrated with measured data in 60 cm drain depth and validated with 40 cm drain depth. HYDRUS-2D could simulate nitrate concentration with the coefficient of determination 0.95 and 0.89 in calibration and validation stages, respectively. The comparison between the volume of drain water and nitrate concentration from the drains in the depths of 40 and 60 cm indicated lower nitrate load in depth of 40 cm. The results obtained proved that the presence of hardpan layer in depth of 25 cm rather than the absence of it causes increase in 3 % of average nitrate concentration and reduce in 17 % of water discharge.  相似文献   
35.
Shortage of fish meal (FM) resources in the marine environment, high price and high demand for this ingredient led researchers to seek for alternative protein resources such as meat and bone meal (MBM). The effects of adding MBM and garlic powder to the shrimp diet on growth performance, muscle composition, amino acid and fatty acid profiles of whiteleg shrimp (5.00 ± 0.23 g) were investigated. A total of six dietary treatments were formulated: 0%MBM (control without garlic powder), 25%MBM and 50%MBM (treatments without garlic powder; WG treatments); 0%MBM+G (control with garlic powder), 25%MBM+G and 50%MBM+G (treatments with garlic powder; G treatments). Our results indicated that increase MBM level in the diets (up to 50%MBM) impaired growth performance, muscle composition, fatty acid and amino acid profiles in the muscle of shrimp. Interestingly, garlic supplementation improved the aforementioned factors so that shrimp fed 50%MBM+G diet had no significant difference when compared to 0%MBM group. The current results indicated that garlic could increase levels of FM replacement by increasing feed intake, improving protein and amino acid utilization. Overall, 50%MBM+G diet is recommended for use in shrimp production.  相似文献   
36.
Background:FH, a hereditary disorder, is caused by pathogenic variants in the LDLR, APOB, and PCSK9 genes. This study has assessed genetic variants in a family, clinically diagnosed with FH. Methods:A family was recruited from MASHAD study in Iran with possible FH based on the Simon Broom criteria. The DNA sample of an affected individual (proband) was analyzed using WES, followed by bioinformatics and segregation analyses. Results:A novel splice site variant (c.345-2A>G) was detected in the LDLRAP1 gene, which was segregated in all affected family members. Moreover, HMGCR rs3846662 g.23092A>G was found to be homozygous (G/G) in the proband, probably leading to reduced response to simvastatin and pravastatin. Conclusion:LDLRAP1 c.345-2A>G could alter the PTB, which acts as an important part of biological pathways related to lipid metabolism. Key Words: Genetic research, LDLRAP1, Hypercholesterolemia, Hydroxymethylglutaryl-CoA Reductase Inhibitors  相似文献   
37.
Background:Variations in mtDNA-CN of PBLs, as a potential biomarker for GC screening has currently been subject to controversy. Herein, we have assessed its efficiency in GC screening, in parallel and in combination with sPG I/II ratio, as an established indicator of gastric atrophy. Methods:The study population included GC (n = 53) and non-GC (n = 207) dyspeptic patients. The non-GC group was histologically categorized into CG (n = 104) and NM (n = 103) subgroups. The MtDNA-CN of PBLs was measured by quantitative real-time PCR. The sPG I and II levels and anti-H. pylori serum IgG were measured by ELISA. Results:The mtDNA-CN was found significantly higher in GC vs. non-GC (OR = 3.0; 95% CI = 1.4, 6.4) subjects. Conversely, GC patients had significantly lower sPG I/II ratio than the non-GC (OR = 3.2; CI = 1.4, 7.2) subjects. The combination of these two biomarkers yielded a dramatic amplification of the odds of GC risk in double-positive (high mtDNA-CN-low sPGI/II) subjects, in reference to double-negatives (low mtDNA-CN-high sPGI/II), when assessed against non-GC (OR = 27.1; CI = 5.0, 147.3), CG (OR = 13.1; CI = 2.4, 72.6), or NM (OR = 49.5; CI = 7.9, 311.6) groups. Conclusion:The combination of these two biomarkers, namely mtDNA-CN in PBLs and serum PG I/II ratio, drastically enhanced the efficiency of GC risk assessment, which calls for further validations. Key Words: Biomarkers, DNA copy number variation, Mitochondrial DNA, Stomach neoplasms  相似文献   
38.
Five isonitrogenous (420 g kg?1 crude protein) and isoenergetic (16.3 kJ g?1) practical diets were formulated to contain fish oil (FO), Kilka fish oil (KFO), linseed (LO), canola (CO) and soybean (SBO) oils fed to juveniles of three‐spot gourami (Trichopodus trichopterus) (initial weight 1 ± 0.03 g) three times per day to apparent satiation for 14 weeks. Results showed the mean final weight of brooders was not significantly affected by dietary oil sources. Specific growth rate for fish fed in SBO and CO diets was statistically higher than for fish fed diet LO. Fish fed diets CO and KFO showed in significantly higher GSI value compared with other diets. Absolute fecundity was greatest in fish fed diets KFO and CO, which significantly differ with other treatments. Except for KFO diet, high fertilization percentages (87.3–93.45%) were observed in other treatments. Fatty acid composition of muscle and egg was found to be positively correlated with their respective dietary lipid sources. High levels of EPA, DHA and n‐3 HUFA in brooders fed diet FO negatively affect egg quality parameters. Therefore, the results demonstrated that vegetable oil‐based diets (CO, SBO and LO, respectively) can positively affect on growth performance of juveniles compared with fish oil‐based diets. Furthermore, CO and LO diets, respectively, showed positive effects on reproductive performance in Ttrichopterus compared with fish oil diets during experimental period under controlled conditions.  相似文献   
39.

Shortage of winter chill has reduced pistachio (Pistacia vera L.) fruit yield and quality from 2015 to 2018 in Iran. In this study accumulated chilling was determined by the chill hour (CH) and the dynamic (DM) model in five regions near Shahrebabak County, Kerman Province, Iran, for dormant season 2017–2018. The CH model has been routinely used in Iran for reporting chilling accumulation for pistachios. This study suggested that the DM better differentiated regional chill accumulations, the impact of chilling on phenological indices of growth and production between cultivars ‘Owhadi’ and ‘Akbari’, with and without rest-breaking (RB) treatments of Volk dormant oil. Volk oil treatment significantly improved vegetative and reproductive development, offset lack of chilling effects on pollination and nut filling, and may have advanced budbreak in some instances.

  相似文献   
40.
In this study, dissolved air flotation (DAF) was examined as a possible treatment method for the removal of chromium from aqueous solution and plating wastewater. Two coagulants, ferric chloride and poly aluminum chloride (PAC), were used for pretreatment of wastewater. Maximum removal of chromium was achieved for poly aluminum chloride (98 %). Artificial neural network was used for the prediction of the DAF system. The best neuron used for the prediction of chromium removal percentage of interpolated wastewater was 6 %. The mean score error and the coefficient correlation were 0.0007542 and 0.997, respectively.  相似文献   
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