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Anthracnose caused by Colletotrichum spp. is one of main strawberry diseases worldwide. The disease recently arrived in Iran and become epidemic in the Kurdistan province. A combination of morphological, molecular and pathogen-host interaction approaches (referred to the consolidated species concept) were applied to isolates from symptomatic strawberry tissues collected in Iran. Multi-gene phylogenetic analysis based on ITS-rDNA, beta-tubulin (TUB2) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) identified the species as the S5 clade of Colletotrichum nymphaeae. No significant intraspecies variation was observed in terms of morphology and pathogenicity. No significant genetic variation was observed among the isolates using inter simple sequence repeat analysis (ISSR) and primer pair combination of ERIC1/BOX and ERIC2/BOX fingerprinting markers. Based on the results of this study, it can be postulated that the C. nymphaeae population in Iran established itself from a single origin due to a founder effect. More generally, molecular dating based on relaxed clocks indicates co-radiation of C. nymphaeae S5 and strawberry plants and suggests high reciprocal specificity between the host and pathogen.  相似文献   
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Background: The aim of this trial was to investigate the effects of different inclusion levels of a partial y defatted black soldier fly(BSF, Hermetia il ucens L.) larva meal on the growth performance, nutrient digestibility, blood profile, gut morphology and histological features of piglets. A total of 48 newly weaned piglets were individual y weighed(initial body weight(IBW): 6.1 ± 0.16 kg) and randomly al ocated to 3 dietary treatments(4 boxes as replicates/treatment and 4 animals/box). BSF larva meal was included at increasing levels(0% [BSF0], 5% [BSF5] and 10% [BSF10]) in isonitrogenous and isoenergetic diets formulated for two feeding phases: I(from d 1 to d 23) and I(from d 24 to d 61). The weight gain(WG), average daily gain(ADG), average daily feed intake(ADFI) and feed conversion ratio(FCR) were calculated for each feeding phase and for the whole trial. The haematochemical parameters and nutrient digestibility of the piglets were also evaluated. A total of 3 piglets per box were slaughtered on d 61 and the slaughtered piglets were submitted to morphometric investigations and histopathological examinations.Results: No overal significant differences were observed for growth performance(P 0.05), except for the ADFI of phase I, which showed a linear response to increasing BSF meal levels(P 0.05, maximum for the BSF10 group). Dietary BSF meal inclusion did not significantly influence the blood profile, except as far as monocytes and neutrophils are concerned,and these showed a linear and quadratic response, respectively, to increasing BSF meal levels(P 0.05, maximum for the BSF10 and BSF5 groups, respectively). On the other hand, the nutrient digestibility, gut morphology and histological features were not affected by dietary BSF meal inclusion(P 0.05).Conclusions: The obtained results show that a partial y defatted BSF larva meal can be used as a feed ingredient in diets for weaned piglets without negatively affecting their growth performance, nutrient digestibility, blood profile, gut morphology or histological features.  相似文献   
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Background: The present work aimed at evaluating the effect of the dietary replacement of soybean oil(S) by two types of insect fats extracted from black soldier fly larvae(H, Hermetia il ucens L.) and yel ow mealworm larvae(T, Tenebrio molitor L.) on growth performance, nutrient digestibility, blood parameters, intestinal morphology and health of growing rabbits.Methods: At weaning, 200 crossbred rabbits(36 days old) were allotted to five dietary treatments(40 rabbits/group): a control diet(C) containing 1.5% of soybean oil and four experimental diets where soybean oil was partially(50%) or totally(100%) substituted by H(H50 and H100) or T(T50 and T100) fats. Total tract digestibility was evaluated on 12 rabbits per treatment. The growth trial lasted 41 d and, at slaughtering(78 days old), blood samples were collected from 15 rabbits per treatment, morphometric analyses were performed on duodenum, jejunum and ileum mucosa,and samples of liver, spleen and kidney were submitted to histological evaluation.Results: No difference was observed between the control and the experimental groups fed insect fats in terms of performance, morbidity, mortality and blood variables. The addition of H and T fats did not influence apparent digestibility coefficients of dry matter, protein, ether extract, fibre fractions and gross energy. Gut morphometric indices and organ histopathology were not affected by dietary inclusion of H and T fats.Conclusions: H and T fats are suitable sources of lipid in rabbit diets to replace soybean oil without any detrimental effect on growth performance, apparent digestibility, gut mucosa traits and health.  相似文献   
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Bifidobacteria strains from human origin were screened for the specific activity (beta-glucosidase activity) involved in the metabolism of dietary flavonoids. Five strains with high beta-glucosidase activity were selected for further metabolism analyses (high-performance liquid chromatography separations) of flavonoid glycosides occurring in Phaseolus vulgaris L. (common bean) seeds and seedlings. All selected strains were found to be active in the conversion of kaempferol 3-O-glucoside, daidzin, genistin, and glycitin into their aglyconic forms. No metabolites were detected after the fermentation tests with the diglucosidic compound kaempferol 3-O-xylosylglucoside. In addition, to verify the effective bioavailability of flavonoid aglycones, the degradation rates of daidzein, genistein, glycitein, and kaempferol, following incubation with selected strains, were monitored. The results showed that the five selected strains of bifidobacteria, being active in the biotranformation of flavonoid glycosides occurring in common bean seeds and seedlings, could be considered as probiotic dietary adjuncts to improve the nutritional and health properties of flavonoid-based products, comprising hypothetical common bean food derivatives.  相似文献   
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Since 2006, the members of the molecular epidemiological working group of the European "EPIZONE" network of excellence have been generating sequence data on avian influenza and avian paramyxoviruses from both European and African sources in an attempt to more fully understand the circulation and impact of these viruses. This review presents a timely update on the epidemiological situation of these viruses based on sequence data generated during the lifetime of this project in addition to data produced by other groups during the same period. Based on this information and putting it all into a European context, recommendations for continued surveillance of these important viruses within Europe are presented.  相似文献   
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Novel swine influenza virus subtype H3N1 in Italy   总被引:2,自引:0,他引:2  
To date, three subtypes of swine influenza viruses, H1N1, H1N2, and H3N2 have been isolated in Italy. In 2006, a novel swine influenza virus subtype (H3N1) was isolated from coughing pigs. RT-PCR performed on lung tissues, experimental infection in pigs with the novel isolate, and cloning the virus by plaque assay confirmed this unique H and N combination. The novel isolate was also antigenically and genetically characterized. Genetic and phylogenetic analysis showed that the complete HA gene of the H3N1 strain has the highest nucleotide identity to three Italian H3N2 strains, one isolated in 2001 and two in 2004, whereas the full length NA sequence is closely related to three H1N1 subtype viruses isolated in Italy in 2004. The remaining genes are also closely related to respective genes found in H1N1 and H3N2 SIVs currently circulating in Italy. This suggests that the novel SIV could be a reassortant between the H3N2 and H1N1 SIVs circulating in Italy.  相似文献   
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