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1.
Evaluating the Effects of Dietary Prebiotic Mixture of Mannan Oligosaccharide and Poly‐β‐Hydroxybutyrate on the Growth Performance,Immunity, and Survival of Rainbow Trout,Oncorhynchus mykiss (Walbaum 1792), Fingerlings
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Ebrahim H. Najdegerami Amir Tokmachi Farideh Bakhshi 《Journal of the World Aquaculture Society》2017,48(3):415-425
This study investigated the effects of dietary poly‐β‐hydroxybutyrate (PHB) and mannan oligosaccharide (MOS) on the growth performance, digestive enzyme activities, and disease resistance of rainbow trout fingerlings. A total of 420 fingerlings, distributed equally into four different groups, each with three replicates, were fed a basal diet (control), 2% PHB (PHB), 0.2% MOS (MOS), or a diet supplemented with a mixture of 2% PHB and 0.2% MOS (PHB+MOS) for 60 d. Results showed that dietary PHB and/or MOS did not cause significant improvement in the growth performance of the fingerlings. The gut pH was markedly reduced; however, the activities of the digestive enzymes (except for pepsin and amylase by dietary PHB) were not significantly improved by the dietary supplements. Results also showed that dietary PHB and/or MOS markedly increased the resistance of the fingerlings toward Yersinia ruckeri infection, while the lowest total antibody was observed in fish fed control and MOS, indicating that MOS exerts its protective effects by modulating other mechanisms. Overall, this study provided a first screening effort to determine the effects of PHB and/or MOS as dietary supplements in rainbow trout fingerlings to develop an optimal prebiotic mix for improving the growth and health status of rainbow trout. 相似文献
2.
Mahdi Ghorbanalizadgan Bita Bakhshi Anoshirvan Kazemnejad Lili Shahin Najar-Peerayeh Bahram Nikmanesh 《Iranian Biomedical Journal》2014,18(3):158-164
Background: The aim of this study was to determine the prevalence of virulence-associated genes and enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) analysis of Campylobacter spp. isolated from children with diarrhea in Iran. Methods: A total of 200 stool specimens were obtained from children under 5 years during July 2012 to July 2013. Detection of C. jejuni and C. coli was performed by standard biochemical and molecular methods. The presence of virulence-associated genes and genetic diversity of isolates was examined using PCR and ERIC-PCR analyses. Results: A total of 12 (6%) Campylobacter spp. were isolated from patients including 10 (4.5%) C. jejuni and 2 (1.5%) C.coli. The flaA, cadF and ciaB genes were present in 100% of isolates, while no plasmid of virB11 gene was present in their genome. The prevalence of invasion-associated marker was 100% among C. coli and was not detected in C. jejuni isolates. The distribution of both pldA and the genes associated with cytolethal distending toxin (CDT) was 58.3% in C. jejuni isolates. Seven distinct ERIC-PCR profiles were distinguished in three clusters using ERIC-PCR analysis. Genotyping analysis showed a relative correlation with geographic location of patients and virulence gene content of isolates. Conclusion: To our knowledge, this is the first molecular survey of Campylobacter spp. in Iran concerning genotyping and virulence gene content of both C. jejuni and C. coli. ERIC-PCR revealed appropriate discriminatory power for clustering C. jejuni isolates with identical virulence gene content. However, more studies are needed to clearly understand the pathogenesis properties of specific genotypes. Key Words: Campylobacter jejuni, Campylobacter coli, Ddiarrhea, Virulence factors 相似文献
3.
In recent years, common bean (Phaseolus vulgaris) and cowpea (Vigna unguiculata) plants in the north of Iran have exhibited symptoms resembling Cercospora leaf spot (CLS) disease. This study was initiated to elucidate the taxonomy and pathogenicity of cercosporoid taxa associated with leaf spot diseases of these two legume crops in Iran. A total of 138 samples with CLS symptoms were collected from cultivated common bean and cowpea species in northern Iran and subjected to microscopic examination, resulting in identification of 98 Cercospora and 59 Pseudocercospora samples. A six-locus phylogenetic analysis (ITS, actA, tef1, gapdh, his3, and cmdA) coupled with examination of the morphology of 42 representative isolates from these samples confirmed that several cercosporoid fungi occur on common bean and cowpea in Iran. Five Cercospora species (C. iranica, C. cf. flagellaris, Cercospora sp. G, Cercospora sp. T, and C. vignigena) and two Pseudocercospora species (P. griseola f. griseola and P. cf. cruenta) were found; of these, C. cf. flagellaris was the dominant species, occurring on both common bean and cowpea. Pathogenicity tests confirmed that all seven species could infect leaves of common bean and/or cowpea. This is the first report of C. iranica, Cercospora sp. G, and Cercospora sp. T associated with common bean and/or cowpea in the world. In addition, C. vignigena was recorded for the first time in Iran. Results achieved in this study will assist strategies for the management of CLS disease of common bean and cowpea. 相似文献
4.
Bakhshi Amrei Shahrbanou Peneva Vlada Rakhshandehroo Farshad Pedram Majid 《European journal of plant pathology / European Foundation for Plant Pathology》2022,162(3):739-750
European Journal of Plant Pathology - Longidorus armeniacae n. sp. is described and illustrated using morphological and molecular data. It was recovered from the rhizosphere of apricot trees in... 相似文献
5.
Investigation on dimensional stability of cotton plain weft knitted fabric manufactured from rotor spun yarn, subjected to
mercerization treatment has been represented. Several fabric samples were mercerized considering variation in time of treatment,
bath temperature, concentration of alkali solution and also mercerizing tension. Values of constant of course (K
c
), constant of wale (K
w
), the area geometry constant (K
s
) which are indicative of fabric dimensional stability were calculated after treatment for mercerized samples. Then, these
values were compared with those of un-treated samples subjected to dry and wet relaxation and also were compared with each
other. Based on the effect of each variable itself and their simultaneous effect, it was concluded that, mercerization treatment
and considered parameters had a distinctive influence on dimensional stability of the fabric. Mercerized samples had better
dimensional stability in comparison with un-treated ones. A comprehensive experimental analysis showed that, there is meaningful
difference between K
s
values of the samples mercerized at various conditions. Also, the area geometry constant (K
s
) achieved after treatment was higher than that of other relaxation methods. 相似文献
6.
Background: Cholera toxin B subunit (CTB) has been extensively considered as an immunogenic and adjuvant protein, but its yield of expression is not satisfactory in many studies. The aim of this study was to compare the expression of native and mutant recombinant CTB (rCTB) in pQE vector. Methods: ctxB fragment from Vibrio cholerae O1 ATCC14035 containing the substitution of mutant ctxB for amino acid S128T was amplified by PCR and cloned in pGETM-T easy vector. It was then transformed to E. coli Top 10F'' and cultured on LB agar plate containing ampicillin. Sequence analysis confirmed the mature ctxB gene sequence and the mutant one in both constructs which were further subcloned to pQE-30 vector. Both constructs were subsequently transformed to E. coli M15 (pREP4) for expression of mature and mutant rCTB. Results: SDS-PAGE analysis showed the maximum expression of rCTB in both systems at 5 hours after induction and Western-blot analysis confirmed the presence of rCTB in blotting membranes. The expression of mutant rCTB was much higher than mature rCTB, which may be the result of serine-to-threonine substitution at position 128 of mature rCTB amino acid sequence created by PCR mutagenesis. The mutant rCTB retained pentameric stability and its ability to bind to anti- cholera toxin IgG antibodies. Conclusion: Point mutation in ctxB sequence resulted in over-expression of rCTB, probably due to the increase of solubility of produced rCTB. Consequently, this expression system can be used to produce rCTB in high yield. Key Words: Escherichia coli, Point mutation, Cholera toxin B subunit (CTB), Protein expression 相似文献
7.
Pomegranate (Punica granatum L.) is one of the oldest known edible fruits. It is native to Iran and spread from Iran to other areas. In this study amplified fragment length polymorphism (AFLP) was used to detect intra- and inter-population genetic diversity of pomegranate. A group of 67 accessions belonged to 4 populations from Iran was studied using eight primer combinations. A total of 221 scorable bands were amplified, of which, 118 (54.13%) were polymorphic. Resolving power (Rp) ranged from 5.70 to 9.21, and the average of polymorphism information content (PIC) per primer pair was 0.40. According to Nei's gene diversity and allelic statistics, Isfahan population had a highest genetic diversity (H = 0.3646, I = 0.5327, Ne = 1.6467). Coefficient of gene differentiation between populations (GST) was 0.124, indicated that mainly proportion of genetic variation (87.6%), was within populations and the remaining (12.4%) of the variation was among populations that, also supported by analysis of molecular variance (AMOVA). The gene flow (Nm) varied from 0.969 to 10.404 between pair-wise populations and was 3.504 among all of the populations. The Jaccard similarity coefficient between individuals ranged from 0.26 to 0.88. The UPGMA dendrogram clustered all 67 accessions into 6 groups. In some cases accessions from same region were grouped together but in most cases, there was gene exchange. To study the genetic relationships among populations, a principal coordinate analysis (PCoA) based on Nei's genetic distances was performed. Results of this study showed that AFLP marker can be a useful tool for investigating the genetic diversity of pomegranate genotypes. 相似文献
8.
Ali Momenpour Ali Imani Davod Bakhshi Ehsan Akbarpour 《International Journal of Fruit Science》2018,18(4):410-435
ABSTRACTIn order to evaluate the tolerance of some almond genotypes to salinity, a factorial experiment was carried out based on completely randomized design (CRD), with two factors: genotypes in 11 levels (Tuono, Nonparaeil, Mamaie, Shokoufeh, Sahand, ‘Ferragnès,’ 1–16, 1–25, A200, 13–40 budded on GF677 rootstock, and GF677 (without budding)) and irrigation water salinity in five levels (0, 1.2, 2.4, 3.6, and 4.8 g/l of natural salt (equal electrical conductivity 0.5, 2.5, 4.9, 7.3, and 9.8 dS/m, respectively) and with 4 replication for each treatment in research greenhouse of Seed and Plant Institute in years 2013 and 2014. The results showed that with increasing salinity concentration, growth indicators include the branch height, branch diameter, number of total leaves, percentage of green leaves, leaf density on the main branch, leaf area and leaf area ratio, relative humidity content, chlorophyll index, chlorophylls a, b, total, scion fresh and dry weight, root fresh and dry weight have been reduced in the all genotypes studied, but percentage of necrotic leaves, percentage of downfall leaves, root fresh and dry weight ratio to scion fresh and dry weight, relative ionic percentage, and cell membrane injury percentage of leaves were increased. The results of chlorophyll fluorescence showed that salinity stress affected on the young trees by increasing the amount of minimum fluorescence (FO) and decreasing the maximum fluorescence (Fm) and reduced variable fluorescence (Fv) in the plants and reduced variable fluorescence ratio to maximum fluorescence of 0.83 in the control plants to 0.72 in Sahand cultivar and GF677 rootstock. The result showed that type of scion was affected in obstruction of Na+ absorption by the roots and their transported to leaves, as well as was affected in increasing uptake of K+ by the roots and their transported to leaves. In this research, GF677 is well tolerated to water salinity to 4.9 dS/m but with higher range of salinity showed stress effects. The result showed that type of genotypes budded on GF677 rootstock was very effective in tolerant to salinity. Overall, ‘Ferragnès’ was recognized as the most tolerant cultivar to salinity stress. This cultivar could tolerate salinity 3.6 g/l (Ec: 7.3 dS/m). Also, Sahand was recognized as the most sensitive cultivar to salinity stress. 相似文献
9.
Bakhshi B Pourshafie MR Navabakbar F Tavakoli A Shahcheraghi F Salehi M Faradjzadegan Z Zahraei SM 《Iranian Biomedical Journal》2008,12(3):159-165
Background: The virulence of a pathogenic Vibrio cholerae is dependent on a discrete set of genetic determinants. In this study, we determined the distribution of virulence determinants among the clinical and environmental isolates of V. cholerae. Methods: The antibiotic resistance profiles of the isolates were determined using standard disk diffusion assay. PCR assay was performed to analyze the presence of toxin genes of ctx, zot and ace. The composition of cholera toxin encoding element (CTX) region flanking of the V. cholerae isolates was also analyzed. Results: All of the clinical isolates (100%) showed a complete set of virulence genes and also the attachment site of the filamentous bacteriophage CTXphi. None of the environmental isolates contained the virulence genes and the attachment site of the CTXphi. Analysis of the flanking regions including the toxin-linked cryptic element and repeat in toxin genes revealed their integrity in the clinical isolates while in the environmental isolates they were absent or contained incomplete sequences. Comparison of the antibiotic resistance assay of the environmental and clinical isolates showed a significant difference in the resistance profiles of the isolates obtained from the two sites. High rates of resistance to co-trimoxosol, streptomycin and chloramphenicol were found with clinical isolates. Conclusion: The absence of all virulence determinants in the environmental strains may suggest that certain ecological features must be present for V. cholerae to acquire a complete set of virulence determinants and to turn them into pathogenic strains. 相似文献
10.