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21.
Kiuomars Rohani‐Ghadikolaei Wing‐Keong Ng Eesa Abdulalian Aghajari Naser Aftabsavar Yusuf 《Aquaculture Research》2012,43(10):1487-1498
Aqueous extracts of green [Ulva lactuca Linnaeus and Enteromorpha intestinalis (Linnaeus) Nees] and red [Gracilaria corticata (J. Agardh) J. Agardh] seaweeds from the Persian Gulf of Iran were examined for their potential usefulness as components of microalga Isochrysis galbana culture medium against conventional f/2 medium. Isochrysis galbana was successfully cultured using the tested seaweed extracts (SWE) and exhibited higher or similar cell density and biomass when SWE were used as a supplement or an alternative medium respectively. When the SWE were used as an alternative medium, microalgal protein, lipid and ash content were similar but carbohydrate increased compared with control. Total saturated fatty acids decreased with a corresponding increase in total mono‐ and polyunsaturated fatty acids following supplementation of f/2 medium with SWE. Eicosapentaenoic acid (EPA) was not affected by SWE treatments but docosahexaenoic acid (DHA) tended to decrease, except for I. galbana cultured with U. lactuca extract. With the exception of potassium, SWE did not significantly impact the mineral content of cultured I. galbana. The study points to the potential usefulness of specific SWE in the production of microalgae as a food source in aquaculture. 相似文献
22.
Most ecological studies in North Africa reveal a process of continuous degradation of rangeland ecosystems as a result of overgrazing. This degradation appears across the decreasing of perennial grass diversity. Indeed, the majority of steppe ecosystems are characterized by a low density of perennial grass species at present. This study evaluated the effects of temperature and water limitation on the seed germination of Stipagrostis ciliata(Desf.) de Winter, a perennial grass species. The seeds were collected from the Bou Hedma Park, Sidi Bouzid Governorate, Central Tunisia. The thermal time and hydrothermal time models were used to describe the seed germination of S. ciliata under different water potentials and temperatures. The germination response of S. ciliata seeds in darkness was evaluated over a range of temperatures(15°C, 20°C, 25°C, 30°C and 35°C) and across a wide range of osmotic potentials(0.0, –0.2, –0.6, –1.2, –1.6 and –2.0 MPa) of the polyethylene glycol(PEG6000) solutions at each temperature level. Among the tested temperatures, 25°C was found to be the optimal temperature to the germination of S. ciliata seeds. The final germination percentage(75.2%) was obtained with distilled water. The progressive decrease of osmotic potential of the PEG6000 solutions inhibited the seed germination. However, the number of days to first germination was increased with a reduction of osmotic potential. A significant positive relationship was identified between final germination percentage of S. ciliata seeds and osmotic potential of the PEG6000 solutions, with R~2 ranging from 0.5678 to 0.8761. Furthermore, a high degree of congruency between predicted and observed germination time course curves was observed. In general, S. ciliata exhibits a significant adaptation capacity for water limitation and high temperature in arid ecosystems. 相似文献
23.
This experiment was conducted to evaluate the effects of three nutrient recipes containing different concentrations of macronutrients in the vegetative stage [Vegetative Nutrient Solution: (VNS-I, VNS-II, and VNS-III)] and two nutrient recipes in reproductive stage [Reproductive Nutrient Solution: (RNS-I and RNS-II)], on physiological and biochemical parameters of strawberry ‘Paros’ in a soilless system. The results indicated the significant effects of nutrient solution on the photosynthetic capacity, yield, minerals uptake and titratable acidity of strawberry fruits. In the other hand fruit total soluble solids affected by vegetative nutrient solution. The highest yield was obtained under application of lowest level of minerals. Vegetative growth including leaf number and leaf area, as well as total chlorophyll were the highest as potassium (K+), calcium (Ca2+), and nitrogen (N) concentrations were increased. The highest content of N and Ca2+ uptake were in VNS-III × RNS-I formulation. Additionally, the highest vitamin C was in VNS-I formulation. Moreover, the most firmed fruits and the highest post-harvest shelf life of fruits were produced in VNS-III × RNS-I formulation. 相似文献
24.
Triticeae γ-type seed prolamins have undergone many rounds of gene duplications during evolution. However, the population genetics of total Triticeae γ-prolamin genes has not been studied in an evolutionary perspective so far. Here, evolutionary pattern of γ-prolamin multigene family containing 557 sequences from wheat and closely related species (γ-gliadins), rye (γ-secalin) and barley (γ-hordeins) was investigated. Furthermore, Triticeae genomes were searched for low immuno-reactive celiac disease (CD) epitope contents in their γ-prolamins for the possibility of developing less immunogenic cultivars. Large numbers of haplotypes with segregating sites and mutations in γ-type seed prolamin multigene family were evident. Polymorphism analyses of both promoters and coding regions of species-specific γ-prolamins demonstrated no deviation from neutral theory. The sliding window revealed that most of the singleton polymorphic sites are resided in the variable R1 domain. Furthermore, the significant negative Tajima’s D and H tests’ values of each groups 1, 2, 3, and 8 showed a selective sweep for R and D genome duplication processes. The dN/dS ratio analysis revealed strong purifying selection acting upon duplication of the two ancestral branches, while the neutral selection among overall groups was observed. Our results support previously reported findings that the groups of 2, 3, 8 (D genome) and 10 (A genome) can potentially be recommended for selection approaches or genetic engineering of less immunogenic cereal grains. Furthermore, the results provide new insights on the evolutionary dynamics of γ-prolamin multigene family, polyploidy speciation and phylogeny of Triticeae species. 相似文献
25.
A metabolic approach to understanding adaptation to sea water by endangered Persian sturgeon,Acipenser persicus fingerlings 
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下载免费PDF全文 Saeed Hajirezaee Ali Reza Mirvaghefi Hamid Farahmand Naser Agh 《Aquaculture Research》2018,49(1):341-351
In this study, metabolic responses of Persian sturgeon fingerlings to hyperosmotic condition were investigated by NMR‐based metabolomics. Persian sturgeon fingerlings (n = 2010, mean total weight: 3.2 ± 0.6 g; mean total length: 8.5 ± 1.5 cm) were held in freshwater (FW) for 96 hr and then acclimated in brackish water (BW) (12 g/L) for 24 hr. Blood samples were taken before and after salinity acclimation. The major metabolite changes corresponding to salinity acclimation were related to amino acids, osmolytes and energy metabolites. The plasma glucose levels increased significantly after 24 hr acclimation in BW (p < .05). Other energetic metabolites (acetate, acetoacetate, beta‐hydroxybutyrate, phosphocreatine, creatine, glycerol) showed no significant changes after 24 hr salinity challenge (p > .05). The osmolytes (taurine, trimethylamine‐N‐oxide, choline, N,N‐dimethylglycine) and amino acids (aspartate, glutamate, glutamine, leucine, phenylalanine, β‐alanine, histidine, threonine, cysteine) declined significantly after 24 hr acclimation in BW (p < .05). However, the levels of glycine elevated after 24 hr acclimation in BW (p < .05). Other amino acids including aspargine, isoluecine, Tyrosine, Tryptophan, Valine, and Lysine showed no significant changes after salinity challenge (p > .05). The considerable decreases in almost all plasma amino acids and all osmolytes showed specific importance of these metabolites in osmotic adaptation of fish in BW. Also, it seems that Persian sturgeon fingerlings rely more on oxidation of glucose to meet energetic requirements of osmoregulation than oxidation of lipids, as we observed no detectable changes in metabolites associated with lipid oxidation during osmotic acclimation in BW. Our results may help to understand osmoregulation in a chondrostei fish species from a metabolic approach. 相似文献
26.
Sebastián Meier Gustavo Curaqueo Naser Khan Nanthi Bolan Joaquín Rilling Catalina Vidal Natalia Fernández Jacquelinne Acuña María-Eugenia González Pablo Cornejo Fernando Borie 《Journal of Soils and Sediments》2017,17(5):1237-1250
Purpose
Copper (Cu) contamination has been increasing in land ecosystems. Biochars (BCs) and arbuscular mycorrhizal fungi (AMF) are known to bind metals, and metallophyte can remove metals from soils. Will BC in combination with AMF contain the Cu uptake by a metallophyte growing in a metal-contaminated soil? The objective of this study was to investigate the effects of BCs on the Cu immobilization and over soil microbial communities in a metal-contaminated soil in the presence of AMF and metallophyte.Materials and methods
Two BCs were produced from chicken manure (CMB) and oat hull (OHB). A Cu-contaminated sandy soil (338 mg kg?1) was incubated with CMB and OHB (0, 1, and 5 % w/w) for 2 weeks. Metallophyte Oenothera picensis was grown in pots (500 mL) containing the incubated soils in a controlled greenhouse for 6 months. A number of analyses were conducted after the harvest. These include plant biomass weight, microbial basal respiration, and dehydrogenase activity (DHA), AMF root colonization, spore number, and glomalin production; changes in fungal and bacterial communities, Cu fractions in soil phases, and Cu uptake in plant tissues.Results and discussion
The BCs increased the soil pH, decreased easily exchangeable fraction of Cu, and increased organic matter and residual fraction of Cu. The BCs provided favorable habitat for microorganisms, thereby increasing basal respiration. The CMB increased DHA by ～62 and ～574 %, respectively, for the low and high doses. Similarly, the OHB increased soil microbial activity by ～68 and ～72 %, respectively, for the low and high doses. AMF root colonization, spore number, and total glomalin-related soil protein (GRSP) production increased by ～3, ～2, and ～3 times, respectively, in soils treated with 1 % OHB. Despite being a metalophyte, O. picensis could not uptake Cu efficiently. Root and shoot Cu concentrations decreased or changed insignificantly in most BC treatments.Conclusions
The results show that the BCs decreased bioavailable Cu, decreased Cu uptake by O. picensis, improved habitat for microorganisms, and enhanced plant growth in Cu-contaminated soil. This suggests that biochars may be utilized to remediate Cu-contaminated soils.27.
This study was carried out to determine the seroprevalence of feline leukemia virus (FeLV), feline immunodeficiency virus (FIV) and Toxoplasma gondii (T. gondii) infection among stray and owned cats in southeastern Iran and to identify the influence of age, sex, lifestyle, health status, and laboratory findings on seropositivity. The overall infection rate for FIV, FeLV, and T. gondii was 19.2%, 14.2%, and 32.1% respectively. Results of the multivariate logistic regression analysis showed that old adults more likely to be seropositive than juveniles for FIV, FeLV, and T. gondii (adjusted odds ratios [ORs], 1.84, 1.56, and 2.57 respectively). Anemic and diseased cats ([ORs], 6.62 and 0.9) were at a greater risk of testing positive for FeLV. Male cats were 4.91 times as likely to have FIV as were female and hyperglobulinemia was significantly more prevalent in FIV-infected cats ([ORs], 3.4). In conclusion, FIV and FeLV seem to be endemic in Iran and retroviral-associated immunosuppression may be a risk factor for active toxoplasmosis in infected cats. 相似文献
28.
Prediction breeding value and genetic parameter in Iranian Holstein bulls for milk production traits
Mashhadi MH Kashan NE Nassiry MR Torshizi RV 《Pakistan journal of biological sciences: PJBS》2008,11(1):108-112
Data set included records of 43303 cows for first lactation. Records were collected from 2000 to 2006 in Animal Breeding Center of Iran Studied traits were yield of milk, fat, protein and percentage of fat and protein. Total number of animal was 197561 individual in pedigree. Genetic and phenotypic parameters were estimated with REML method under single trait Animal Model. Breeding values were predicted with BLUP procedure. The model for the analyses included the factors herd-year-season as fixed factor (1694 levels), animal as random effect and age at calving as co variable with minimum and maximum of 23 and 36 month. Respectively the estimated heritabilities were 0.35 (+/-0.02), 0.33 (+/-0.02), 0.31 (+/-0.017), 0.28 (+/-0.02), 0.27 (+/-0.016) for milk, fat, protein yield, percent of fat and protein. Mean of breeding values of sires were 180.2 (+/-28.2), 3.7 (+/-1.26), 2.3 (+/-1.06), -0.036 (+/-0.014) and -0.028 (+/-0.009) for milk, fat, protein yield, percent of fat and protein, respectively. 相似文献
29.
Identification of bacterial agents causing mortality in postlarvae of giant freshwater prawn (Macrobrachium rosenbergii) in south‐west coastal districts of Bangladesh 下载免费PDF全文
下载免费PDF全文 Farzana E Hossain Abu Mohammed Ramim M Shafiqur Rahman Ali Muhammad Omar Faruque M Niamul Naser Muhammad Manjurul Karim 《Aquaculture Research》2017,48(7):3545-3555
Following an incidence of freshwater prawn Macrobrachium rosenbergii postlarvae (PL) mortality in hatcheries in summer 2012, samples from dead PL, rearing water and prawn feed from two south‐west coastal districts of Bangladesh were collected to isolate, identify and characterize the agents causing PL mortality. Antibiogram profile of sixteen randomly selected bacteria, isolated from dead PL, that grew on TCBS, to 20 different antibiotics belonging to 12 major groups revealed that the drug resistance pattern varied from moderate (56% to the drugs: ciprofloxacin, cefotaxime, nitrofurantoin, kanamycin) to complete (to penicillin, ceftazidime and oxacillin) level. To identify the isolates, amplified rDNA restriction analysis (ARDRA) classified them in to four groups, and RAPD (randomly amplified polymorphic DNA) typing yielded nine different types of isolates within these four ARDRA groups. The 16S rDNA gene sequences identified that the groups were genotypically diverse belonging to the bacterial species: Enterobacter cloacae, Klebsiella pneumoniae, Exiguobacterium profundum and Enterococcus casseliflavus, respectively, that all demonstrated their killing potential to PLs in a simulated environment. The study therefore identified four different bacterial pathogens, one of which, Exiguobacterium profundum is reported for the first here in Bangladesh, that demand special consideration for disease management strategy. 相似文献
30.
Mass culture of fairy shrimp Branchinecta orientalis (G. O. Sars 1901) (Crustacea: Anostraca) using effluent of rainbow trout Oncorhynchus mykiss (Walbaum 1792) ponds 下载免费PDF全文
下载免费PDF全文 Navid Pormehr Yabandeh Lynda Beladjal Naser Agh Behrooz Atashbar Gilbert Van Stappen 《Aquaculture Research》2017,48(11):5455-5462
The variable quality and high price of Artemia (Leach 1819) cyst products, used worldwide as live food, motivate aquaculturists to find an appropriate alternative, especially for fresh/brackish water organisms. In this study, Branchinecta orientalis (G. O. Sars 1901), a common fairy shrimp in north‐western Iran, was reared for 15 days using effluent from trout ponds enriched with effluent filtrate as sole feed, or co‐fed with microalgae (Scenedesmus sp.). The effluent filtrate was replaced by algae at different ratios (25% and 50%), and feeding experiments were designed at densities of 100, 200 and 400 individuals/L in 3‐L containers and at 100 individuals/L in 20‐L containers. The results indicated that, at a certain density, the final length and survival were not significantly affected by different feeding regimes (p > .05). In 3‐L containers, the highest length and survival were observed at the lowest density. B. orientalis contained the highest amounts of proteins, carbohydrates and lipids, though, when co‐fed algae, although the differences with the treatment fed solely effluent filtrate were often limited. Inclusion of algae in the diet also resulted in higher levels of a number of PUFAs. Our study proves that B. orientalis can be mass‐cultured successfully using trout effluent as culture medium without additional microalgae. Fish pond effluent is massively available as a cheap food source. Recycling aquaculture effluent for this type of live food production contributes to lowering the use of natural resources and to less discharge of nutrient loads into natural water bodies. 相似文献