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11.
This study investigated the effects of dietary humic acid sodium salt on growth performance, haemato‐immunological and physiological responses, and resistance of rainbow trout, Oncorhynchus mykiss to Yersinia ruckeri. The experimental fish were divided into four groups; three of them were fed with humic acid incorporated diets (0.3% H3, 0.6% H6, 1.2% H12) and an additive free basal diet served as the control. Growth performance and haematological parameters of rainbow trout were not affected by humic acid supplemented diets (p > 0.05). However, dietary humic acid especially with 0.6% incorporation significantly increased stomach pepsin, intestinal trypsin and lipase activities p < 0.05. Following 60 days of feeding trial, fish were challenged with Yersinia ruckeri for 20 days. At the end of the challenge period, significantly higher (p < 0.05) survival rates were found in the 6% humic acid group compared to all other experimental treatment. Thus humic acid might replace antibiotics in diets for rainbow trout to control yersiniosis.  相似文献   
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13.
Macrosiphum rosae (L.) is one of the most destructive pests for Rosa damascena (Miller) when it is found in high numbers. In order to understand the population dynamics of this pest, our priority should be the determination of what extent environmental factors affect the pest population. In this study, we apply fuzzy logic modeling to visualize the population variations, which depends on the environmental factors (temperature and humidity), by using the data obtained from the field studies. After that, we determine the values of temperature and humidity that makes the number of M. rosae maximum by using the filled function method as a global optimization technique.  相似文献   
14.
Nano-TiO2 based multilayer nanocomposite films were fabricated on cationically modified woven cotton fabrics by layer-by-layer molecular self-assembly technique. Cationization process was used to obtain cationic surface charge on cotton fabrics. Attenuated total reflectance Fourier transform infrared spectroscopy analyses were used to verify the presence of cationic surface charge and multilayer films deposited on the fabrics. Scanning electron microscope micrographs of poly(sodium 4-styrene sulfonate)/TiO2, nano polyurethane/TiO2, and TiO2/poly(diallyldimethylammonium chloride) multilayer films deposited on cotton fabrics were taken. With nano-TiO2 based multilayer film deposition, the protection of cotton fabrics against UV radiation is enhanced. The UV protection durability of the self-assembled multilayer films deposited on the cotton fabrics was analyzed after 10 and 20 washing cycles at 40 °C for 30 min. Air permeability and whiteness value analysis were performed on the untreated and multilayer film deposited cotton fabrics. The effect of layer-by-layer deposition process on tensile strength properties of the warp and weft yarns was determined.  相似文献   
15.
The stuffed mussel is a traditional, ready-to-eat food in Turkey which is produced by cooking rice and various spices filled inside the mussel. This article examines the effect on sensory, chemical, and microbiological parameters of stuffed mussels of two gas mixtures—MAP1 50% N2/50% CO2 and MAP2 100% CO2—used as modified atmospheres for cold storage at +4°C. Air packaged samples were chosen as the control group. Based primarily on sensory characteristics, MAP1 gas mixture was the most effective for stuffed mussel. According to sensory results, it has been determined that the control samples kept until the 11th day, while the MAP1 and the MAP2 groups kept until the 13th day. Of the chemical indices determined, the TVB-N values of MAP1 and MAP2 remained lower than the proposed acceptability limits of 20 mg N/100 g, up to 13 days of storage. Microbiological analysis results did not find any differences between the groups. It was found that the shelf life of air and MAP1-MAP2 packaged samples were 7 and 11 days, respectively.  相似文献   
16.
A nutrition trial with striped catfish (Pangasianodon hypophthalmus) juveniles was undertaken to evaluate the effect of replacing dietary fishmeal (FM) protein with corn gluten meal (CGM). A diet with FM as the main protein source was used as the control diet (FM). Five experimental diets (approximately 320 g kg?1 crude protein) were formulated to progressively replace 20% (CGM20), 40% (CGM40), 60% (CGM60), 80% (CGM80) and 100% (CGM100) of FM protein. Fifteen fish per tank (initial weight 11.2 ± 0.6 g) were randomly distributed into 18 80‐litre fibreglass tanks connected to a closed recirculation system (temperature 30.3 ± 1.0 °C). The diets were tested in triplicate for 12 weeks. The final weight and specific growth rate (SGR) of fish fed diets CGM20, CGM40 and CGM60 were not significantly different compared to fish fed the FM diet. Feed intake (FI) tended to decrease with increasing dietary CGM level. Striped catfish fed FM, CGM20 and CGM40 had significantly lower feed conversion ratio (FCR) compared with fish fed CGM80 and CGM100 (< 0.05). The protein efficiency ratio (PER) of fish fed the CGM80 and CGM100 diets was significantly lower than those of all other treatments (< 0.05). Total ammonia‐nitrogen (TAN) excretion increased with elevated dietary CGM inclusion. The viscerosomatic index (VSI) of fish fed the CGM80 and CGM100 diets were significantly higher (< 0.05) than those of fish fed the other treatments. The crude lipid content in the final body composition of the striped catfish was elevated significantly with increasing dietary CGM levels. Fish fed the CGM80 and CGM100 diets displayed haematocrit levels significantly lower (< 0.05) than those fed the other diets. The haemoglobin content in fish was significantly higher in fish fed CGM20 and lower at CGM100 compared to fish fed the FM diet. The results of the present trial indicated that the optimum level of FM protein replacement with CGM determined by quadratic regression analysis was 25.1% on the basis of maximum SGR.  相似文献   
17.
Genotype X environment interactions were estimated for several traits in potato from a combined analysis of 11 genotypes grown at 3 locations for 2 years. Genotype X location X year and Genotype X location interactions were significant for the majority of the traits studied. Yield, reducing sugar content, dry matter content, leaf area, plant height and starch content should be tested over multiple locations and years in order to separate the genotype × environment interaction components from the total genotypic variance.  相似文献   
18.
Journal of Plant Diseases and Protection - Sweet cherry leaf spot, caused by Alternaria spp., causes significant yield losses to sweet cherry production globally. This study was aimed at...  相似文献   
19.
The authors used the empirical equations of mathematical modelling for the energy and protein balance simulation, with the view of calculating the body weight gain in broilers fed various diets. The results found by using the model were compared with the experimental data obtained by several authors. A standard deviation of +/- 1.20% and a mean error of +/- 0.28% and a mean error of +/- 0.28% which proved that the model average was a sufficient estimate of the experimental average were found. Furthermore, using the regression method, a significant correlation of variables was evidentiated.  相似文献   
20.
In 2009 a greenhouse experiment was conducted to determine the effects of boron (B) and plant growth-promoting rhizobacteria (PGPR) on wheat (Triticum aestivum spp. vulgare cv ‘Bezostiya’) and barley (Hordeum vulgare cv ‘Tokak’) on plant growth, freezing injury, and antioxidant enzyme capacity. Results showed that boron (0, 1, 3, 6, 9 kg B ha?1) and PGPR application (Bacillus megaterium M3, Bacillus subtilis OSU142, Azospirillum brasilense Sp245 and Raoultella terrigena) at which 50% of leaves were injured (LT50) values and ice nucleation activities in both plants were found statistically significant. Boron application with all PGPR strains decreased LT50 values in wheat and barley plants under noncold stress (NCS) and cold stress conditions (CS). There were statistically significant differences between bacterial inoculation and B fertilizer in terms of root and shoot dry weight under NCS and CS conditions. Reactive oxidative oxygen species (ROS) and antioxidant enzyme activities (SOD, POD, CAT) were negatively affected CS conditions and decreased with reduced temperatures of media, but B and PGPR applications alleviated the low-temperature deleterious effects in both plants species tested. The lowest ROS and antioxidant enzyme (SOD, POD, CAT) of wheat and barley were observed with 6 kg B ha?1 with R. terrigena.  相似文献   
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