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41.
Mojtaba Mohammadi Arani Amir Parviz Salati Omid Safari Saeed Keyvanshokooh 《Aquaculture Nutrition》2019,25(4):854-861
This study was carried out to assess the effects of Pediococcus acidilactici on zebrafish (Danio rerio). Different levels of P. acidilactici including 0, 1 × 106, 2 × 106, 4 × 106 and 8 × 106 colony‐forming unit per g of the diet (cfug?1) were examined in fish with 120 ± 10 mg weight for 60 days in a completely randomized design. The results showed that the best growth indices were recorded in group 4 × 106 cfug?1 (p < 0.05). The highest number of total viable count and lactic acid bacteria of intestine were found in group 4 × 106 cfug?1 (p < 0.05). The maximum activity of digestive enzymes including amylase, lipase, protease and alkaline phosphatase was observed in group 4 × 106 cfug?1. The highest activity for superoxide dismutase was recorded in group 4 × 106 cfug?1 while catalase, glutathione peroxidase and glutathione reductase showed the highest activity in group 8 × 106 cfug?1. The most growth inhibition zone of Aeromonas hydrophylla, Flavobacterium columnare, Vibrio anguillarum and Edwardsiella tarda was found in group 4 × 106 cfug‐1 (p < 0.05). Therefore, P. acidilactici as a probiotic improved growth and immunity of the zebrafish and could be used by zebrafish farmers. 相似文献
42.
Ghasem Mohammadi Taida Juliana Adorian Gholamreza Rafiee 《Aquaculture Nutrition》2020,26(5):1476-1492
The present research explored the effects of Bacillus subtilis on water quality, growth, immune responses, endotoxemia and protection against lipopolysaccharide (LPS) damages in Nile tilapia Oreochromis niloticus under biofloc system. B. subtilis was added at 0, 1, 2, 3 and 4 grams (1.19 × 108 CFU/g) per kg of basal diet, named T1 (control), T2, T3, T4 and T5, respectively, and fed to fish (14.82 ± 0.42 g) for 50 days. The concentrations of TAN, NO2 and NO3 were significantly reduced, and fish fed probiotics displayed significantly better growth performances versus the control, concomitantly with significantly enhanced activities of digestive enzymes. They also showed significantly declined serum glucose and cholesterol vice versa significantly improved immune responses (total protein, albumin, globulin, lysozyme, alternative complement, protease, immunoglobulins, alkaline phosphatase and respiratory burst), antioxidant capacity (superoxide dismutase, total antioxidant capacity, malondialdehyde) and skin mucus parameters (total protein, lysozyme, alternative complement, protease, immunoglobulins). Meanwhile, significantly lower endotoxin (LPS) concentrations were detected in the intestines and serum of fish fed probiotics. LPS challenge induced profound oxidative stress and impaired immune responses. Interestingly, probiotic alleviated LPS‐induced damages and restored mentioned parameters. In conclusion, B. subtilis effectively enhanced fish production, immunity and protection against LPS‐induced damages in tilapia under biofloc system. 相似文献
43.
Asad Mohammadi Zarejabad Mohammad Ali Jalali Mohammad Sudagar Somayeh Pouralimotlagh 《Fish physiology and biochemistry》2010,36(3):655-659
The effect of environmental salinity on hematological parameters of great sturgeon Huso huso juveniles was studied. Five-month-old juveniles (mean body weight 28.3 ± 2.1 g) were subjected to 0, 3, 6, 9, and 12 ppt
salinities. The hematological parameters were assessed after a period of 20 days rearing at these salinities. After transfer
from fresh water to brackish water, red blood cells, hematocrit, haemoglobin and mean corpuscular haemoglobin decreased, but
mean corpuscular volume increased. Mean corpuscular haemoglobin concentration, white blood cells, monocyte counts, and eosinophil
counts showed no significant variations with increase in environmental salinity. An increase was found in lymphocyte counts
according to the increase of salinity from 0 to 12 ppt, while the fresh water control group maintained basal levels. Decrease
in neutrophil counts was observed in great sturgeon with increase in environmental salinity. These data show significant effect
of salinity on the blood parameters of great sturgeon. 相似文献
44.
Wael Morad Semida Taia Ali Abd El-Mageed Khaulood Hemida Mostafa Mohamed Rady 《The Journal of Horticultural Science and Biotechnology》2019,94(5):632-642
Plant biostimulants are an emerging trend of crop management products which can enhance nutrient uptake, plant growth and productivity under various abiotic stresses. The ability of diluted bee-honey extract (DHE) to enhance the tolerance of onion plants to salinity stress has been investigated. Two-season field experiments were consecutively conducted in 2015/16 and 2016/17 to study the effect of 25–50 g/L DHE foliar application on growth, yield, physio-biochemical attributes, and antioxidative defence of two onion cultivars (i.e. GizaRed and Giza-20) grown on a saline soil (EC = 8.81 dS m?1). Results exhibited that DHE significantly increased biomass production, bulb yield and water use efficiency, leaf photosynthetic and pigments contents. Additionally, DHE applicati\on also improves osmoprotectants, membrane stability index (MSI) and relative water content (RWC), and enzymatic and non-enzymatic antioxidants of both onion cultivars in comparison with untreated control plants. In general, both cultivars showed a similar response to the DHE. Results of this study highlighted the potential impact of DHE as a promising plant bio-stimulant for overcoming the harmful effects of soil salinity stress by increasing the activity of plant antioxidative defence systems 相似文献
45.
We used a goal programming technique to determine the optimal harvest volume for the Iranian Caspian forest. We collected data including volume, growth, wood price at forest roadside, and variable harvesting costs. The allometric method was used to quantify seques- trated carbon. Regression analysis was used to derive growth models. Expected mean price was estimated using wood price and variable harvesting costs. Questionnaire was used to determine the constraints and the equation coefficients of the goal programming model. The optimal volume was determined using the goal programming method according to multipurpose forest management. LINGO software was used for analysis. Results indicated that the optimum volumes of species were 250.25 m3.ha-1 for beech, 59 m3.ha-1 for hornbeam, 73 m3.ha-1 for oak, 41 m3.ha-1 for alder, and 32 m3.ha-1 for other species. The total optimum volume is 455.25 m3.ha-1. 相似文献
46.
Forest fires are an important environmental concern worldwide, affecting the soil, forests and human lives. During the process of burning, soil nutrients are depleted and the soil is subsequently more vulnerable to erosion. Nowadays it is necessary to identify the factors influencing the occurrence of fire and fire hazard areas, in order to minimize the frequency of fire and avert damage. Logistic regression was used to study the forest fire risk and identify the most influential factors in the occurrence of forest fires. Climatic variables (temperature and annual precipitation), human factors (distance from streams and farmland) and physiography (land slope and elevation) were considered and their correlation with the occurrence of fires investigated. Results of model validation and sensitivity of various areas to fire were examined with the ROC coefficient and Hosmer–Lemeshow test. The estimated coefficients for the independent variables indicated that the probability of occurrence of fire is negatively related to land slope, site elevation and distance from farmlands, but is positively related to amount of annual precipitation. 相似文献
47.
Modulation of calcium channels in cardiac and neuronal cells by an endogenous peptide 总被引:8,自引:0,他引:8
Calcium channels mediate the generation of action potentials, pacemaking, excitation-contraction coupling, and secretion and signal integration in muscle, secretory, and neuronal cells. The physiological regulation of the L-type calcium channel is thought to be mediated primarily by guanine nucleotide-binding proteins (G proteins). A low molecular weight endogenous peptide has been isolated and purified from rat brain. This peptide regulates up and down the cardiac and neuronal calcium channels, respectively. In cardiac myocytes, the peptide-induced enhancement of the L-type calcium current had a slow onset (half-time approximately 75 seconds), occurred via a G protein-independent mechanism, and could not be inhibited by alpha 1-adrenergic, beta-adrenergic, or angiotensin II blockers. In neuronal cells, on the other hand, the negative effect had a rapid onset (half-time less than 500 milliseconds) and was observed on both T-type and L-type calcium channels. 相似文献
48.
Tropical Animal Health and Production - Separation of autosomal and sex-linked direct additive genetic effects has significant role in sheep breeding programs. Hence, this study was conducted to... 相似文献
49.
Reza Mohammadi Kouresh Nader Mahmoodi Reza Haghparast Stefania Grando Maryam Rahmanian Salvatore Ceccarelli 《Journal of Crop Science and Biotechnology》2011,14(4):281-288
This study was carried out to identify superior barley genotypes for the rainfed areas of western Iran using a participatory
varietal selection (PVS) approach. Three field experiments were conducted in two randomly selected farmers’ fields and in
one rainfed research station in the 2006–07 cropping season with 69 genotypes (including one local and one improved check).
Several univariate and multivariate methods were used to analyze qualitative (farmers’ scores) and quantitative (grain yield)
data. Individual farmers’ scores in each village were positively correlated, indicating that the farmers tended to discriminate
genotypes in similar fashion, although the genotypes actually selected by farmers were different in the two villages. In recent
years, a greater number of farmers in western Iran preferred the improved variety (Sararood-1) over the local barley (Mahali),
while in this project the farmers preferred the new genotypes over the two checks. This was also verified by the quantitative
data showing that the checks were outyielded by the new genotypes. Farmers were efficient in identifying the best genotypes
for their specific environment, as shown by biplot analysis, indicating their competence in selection. The genotypes selected
by the breeder and farmers were almost similar but some differences existed. In conclusion, PVS is a powerful way to involve
farmers for selecting and testing new cultivars that are adapted to their needs, systems and environments. 相似文献
50.
Mohamadi Yalsuyi Ahmad Forouhar Vajargah Mohammad Hajimoradloo Abdolmajid Mohammadi Galangash Mohsen Prokić Marko D. Faggio Caterina 《Veterinary research communications》2022,46(2):389-396
Veterinary Research Communications - Industrial chemical solutions are widely used as a method to disinfection of aquaculture water and environments. The aim of the present study was to evaluate... 相似文献