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61.
Victor O. Akinseye Muideen D. Adebayo Oghenekaro O. Genesis Olubukola D. Adelakun Simeon I. B. Cadmus 《Tropical animal health and production》2018,50(4):761-772
We evaluated the prevalence of mycobacterial infections (i.e., Mycobacterium bovis and non-tuberculous mycobacteria [NTM]) and their associated risk factors among cattle herds and trade cattle in southwestern Nigeria. Through cross-sectional study design, cattle herds from three locations were screened using the single intradermal comparative cervical tuberculin test based on two diagnostic standards; more than 4 mm (? 4 mm) and more than 2 mm (? 2 mm) cut-off points. Abattoir study involved screening trade cattle for tuberculous lesions. Overall, 515 cattle from 45 herds were screened. Using >?4 mm, animal level and herd prevalence of 11.7 and 46.7% were recorded, respectively. Applying the ? 2 mm cut-off, animal level and herd prevalence increased to 31.1 and 60.0%, respectively. Significantly, using the ? 2 mm cut-off, cattle in medium size herds/extensive management system (OR?=?1.6; 95% CI 1.1–2.5) and Sokoto Gudali (OR?=?2.3; 95% CI 1.4–3.8) were more at risk of being positive reactors, while Rahaji (OR?=?0.3; 95% CI 0.1–0.7) breeds of cattle and cows in the peri-urban area (OR?=?0.4; 95% CI 0.2–0.9) were less at risk of being positive reactors. Again, M. avium reactor of 21.7% was observed. In the abattoir, 1797 cattle were examined with 126 lesions suggestive of tuberculosis (TB). Culture/molecular analyses confirmed 2.2% M. bovis and 0.9% NTM infections. Risk factors associated with bovine TB among trade cattle were sex (OR?=?4.0; 95% CI 1.2–13.5) and age (OR?=?0.3; 95% CI 0.1–0.9). We confirm 11.7% prevalence of mycobacterial infections among populations of cattle screened with breed and herd size being major risk factors. 相似文献
62.
Raquel Lucas-González Manuel Viuda-Martos José Ángel Pérez-Álvarez Juana Fernández-López 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(1):67-73
The aim of the work was to study the influence of particle size in the composition, physicochemical, techno-functional and physio-functional properties of two flours obtained from persimmon (Diospyros kaki Trumb. cvs. ‘Rojo Brillante’ (RBF) and ‘Triump’ (THF) coproducts. The cultivar (RBF and THF) and particle size significantly affected all parameters under study, although depending on the evaluated property, only one of these effects predominated. Carbohydrates (38.07–46.98 g/100 g) and total dietary fiber (32.07–43.57 g/100 g) were the main components in both flours (RBF and THF). Furthermore, insoluble dietary fiber represented more than 68% of total dietary fiber content. All color properties studied were influenced by cultivar and particle size. For both cultivars, the lower particle size, the higher lightness and hue values. RBF flours showed high values for emulsifying activity (69.33–74.00 mL/mL), while THF presented high values for water holding capacity (WHC: 9.47–12.19 g water/g sample). The bile holding capacity (BHC) and fat/oil binding values were, in general, higher in RBF (19.61–12.19 g bile/g sample and 11.98–9.07, respectively) than THF (16.12–12.40 g bile/g sample and 9.78–7.96, respectively). The effect of particle size was really evident in both WHC and BHC. Due to their dietary fiber content, techno-functional and physio-functional properties, persimmon flours seem to have a good profile to be used as potential functional ingredient. 相似文献
63.
We investigated the soil and soil water chemistry in abandoned terraced paddy fields (reed stand) and a thicket of deciduous
broad-leaved trees (thicket stand) on the same slope in Sado Island, Japan. The soils gathered from these plots were incubated
under different water conditions to examine the dynamics of dissolved ions. The organic carbon pool in the soil in the reed
stand at the lower slope position was greater than the thicket stand at the middle slope position. The high concentration
of base cations and an almost neutral pH of the soil water at the reed stand corresponded with the high exchangeable cation
concentrations and base saturation in the soil. These results reflect the mineral-rich groundwater percolating down the slope,
which may be produced by chemical weathering. An in situ sulfate reduction in the reed stand at deeper soil horizons was identified.
The different water conditions in the incubated soils affected the soil pH(H2O), transformation of Fe, and dominant anions (NO3
−, HCO3
−, and SO4
2−). These biogeochemical processes were more conspicuous in the reed stand at the lower slope position where the concentrations
of organic matter and base cations were high. When the abandoned terraced paddy field is developed for the conservation of
the Japanese crested ibis (Nipponia nippon) habitat in Sado Island, the reductive subsoil at the lower slope position should be kept waterlogged to limit sulfuric acid
generation. 相似文献
64.
The morphological, physical, and mechanical properties of the nonwood plant fiber bundles of ramie, pineapple, sansevieria,
kenaf, abaca, sisal, and coconut fiber bundles were investigated. All fibers except those of coconut fiber had noncircular
cross-sectional shapes. The crosssectional area of the fiber bundles was evaluated by an improved method using scanning electron
microscope images. The coefficient factor defined as the ratio of the cross-sectional area determined by diameter measurement,
to the cross-sectional area determined by image analysis was between 0.92 and 0.96 for all fibers. This indicated that the
area determined by diameter measurement was available. The densities of the fiber bundles decreased with increasing diameters.
The diameters of each fiber species had small variation of around 3.4%-9.8% within a specimen. The tensile strength and Young’s
modulus of ramie, pineapple, and sansevieria fiber bundles showed excellent values in comparison with the other fibers. The
tensile strength and Young’s modulus showed a decreasing trend with increasing diameter of fiber bundles. 相似文献
65.
Monique L. Sakalidis Jane D. Ray Vincent Lanoiselet Giles E. StJ. Hardy Treena I. Burgess 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(3):379-391
Members of the Botryosphaeriaceae, in particular Lasiodiplodia theobromae, Neofusicoccum parvum, N. mangiferum and Botryosphaeria dothidea, commonly cause stem cankers, dieback and stem end rot of mangoes worldwide. In the current study, eight taxa of Botryosphaeriaceae
were identified as canker-associated fungi, pathogens, potential pathogens or endophytes of mangoes in the Kimberley, Australia.
These include Neoscytalidium novaehollandiae, Ne. dimidiatum, Pseudofusicoccum adansoniae, P. ardesiacum, P. kimberleyense, Lasiodiplodia sp. 1, L. iraniensis and L. pseudotheobromae. The pathogenicity of a selection of these species toward fruit and branches was tested. All were pathogenic to mango in comparison
to the control, with Lasiodiplodia spp. being the most pathogenic. It appears that either geographic isolation or the unique growing conditions in the Kimberley
may have provided an effective barrier to the acquisition or establishment of known botryosphaeriaceous pathogens. Wounds
caused by mechanical pruning may provide an entry point for infection, whilst severe pruning may increase plant stress. 相似文献
66.
Takashi Naito Minoru Tanaka Satoshi Taba Tesuya Toyosato Atsushi Oshiro Kazuko Takaesu Kazuo Hokama Tomio Usugi Shinji Kawano 《Journal of General Plant Pathology》2007,73(2):139-141
In 1999, a disease of chrysanthemum [Dendranthema grandiflorum (Ramat.) Kitamura], characterized by virescence of flowers, occurred in Okinawa Prefecture. The causal agent was identified
as “Candidatus Phytoplasma aurantifolia” based on 16S rDNA sequencing.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB247462. 相似文献
67.
Breakdown and macroinvertebrate colonization of conifer needles (Cryptomeria japonica) and deciduous broadleaves (Euptelea polyandra) were investigated using litter bags in two study sites in streams flowing through a conifer plantation of C. japonica in Shikoku, southwestern Japan (one site with conifer canopy and another with mixed conifer and broadleaved canopy). Breakdown
rates and macroinvertebrate densities were compared between litter species (conifer needle vs broadleaf) and between the two
sites (conifer vs mixed canopy) to determine (1) whether breakdown rate of broadleaves is higher than conifer needles, (2)
whether macroinvertebrates prefer broadleaves to conifer needles, and (3) whether the difference in riparian canopy is reflected
in macroinvertebrate abundance. The results indicated that breakdown rates of broadleaves were higher than those of conifer
needles, suggesting poorer quality of the latter as food for macroinvertebrates. Differences in macroinvertebrate density
between needles and broadleaves were generally consistent with those in breakdown rates: broadleaves tended to have higher
densities than needles, suggesting that conifer needles were not preferred by macroinvertebrates. However, total macroinvertebrate
density in the conifer site was not significantly different from that in the mixed site, although the dominant shredder taxon
differed (conifer site: gammarids; mixed site: lepidostomatids). Although conifer needles are low-quality food for macroinvertebrates,
this may offer some advantages. Conifer needles remain on the streambed for longer periods owing to their lower breakdown
rates, being a constantly available resource. In addition, accumulations of conifer litter may effectively trap and retain
particulate organic matter. 相似文献
68.
Reto M Figueira ME Filipe HM Almeida CM 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(4):139-144
To evaluate the potential benefits and risks associated with tea consumption it is important to identify the constituents
of this beverage. Levels of some minerals, caffeine and catechins in green tea samples commercialized in Portugal were evaluated.
Potassium is the metal present in larger amount (92–151 mg/l). The content of sodium, calcium, fluoride, aluminium, manganese
and iron were 35–69, 1.9–3.5, 0.80–2.0, 1.0–2.2, 0.52–1.9, 0.020–0.128 mg/l, respectively. Chromium and selenium were not
detected. The resulting data showed considerable variability in catechins content. The levels of epigallocatechin gallate
(EGCG) ranged from 117 to 442 mg/l, epicatechin 3-gallate (EGC) from 203 to 471 mg/l, epigallocatechin (ECG) from 16.9 to
150 mg/l, epicatechin (EC) from 25 to 81 mg/l and catechin (C) from 9.03 to 115 mg/l. Caffeine contents in the green tea infusions
studied were between 141–338 mg/l. Green tea infusions provide significant amounts of catechins and could be an important
source of some minerals. 相似文献
69.
Growth,P uptake and rhizosphere properties of wheat and canola genotypes in an alkaline soil with low P availability 总被引:1,自引:0,他引:1
Zakaria Solaiman Petra Marschner Dongmei Wang Zed Rengel 《Biology and Fertility of Soils》2007,44(1):143-153
The aim of the present study was to assess the role of soil type on growth, P uptake and rhizosphere properties of wheat and
canola genotypes in an alkaline soil with low P availability. Two wheat (Goldmark and Janz) and two canola genotypes (Drum
and Outback) were grown in a calcareous soil (pH 8.5) at two P levels [no P addition (0P) or addition of 200 mg kg−1 P as Ca3(PO4)2 (200P)] and harvested at flowering or maturity. Shoot and root dry weight, root length and shoot P content were greater in
the two canola genotypes than in wheat. There were no consistent differences in available P, microbial P and phosphatase activity
in the rhizosphere of the different genotypes. Shoot P content was significantly positively correlated with root length, pH
and phosphatase activity in the rhizosphere. The microbial community composition, assessed by fatty acid methylester analysis,
of the canola genotypes differed strongly from that of the wheat genotypes. The weight percentage bacterial fatty acids, the
bacteria/fungi (b/f) ratio and the diversity of fatty acids were greater in the rhizosphere of the canolas than in the rhizosphere of the wheat
genotypes. In contrast to the earlier studies in an acidic soil, only small differences in growth and P uptake between the
genotypes of one crop were detected in the alkaline soil used here. The results confirmed the importance of root length for
P uptake in soils with low P availability and suggest that the rhizosphere microbial community composition may play a role
in the better growth of the canola compared to the wheat genotypes. 相似文献
70.
Tetsuo Tamada 《Journal of General Plant Pathology》2007,73(1):76-80
Four lines (designated MR0, MR1, MR2, and M8) from 13 accessions of Beta vulgaris subsp. maritima were selected on the basis of phenotypes produced after foliar rub-inoculation with Beet necrotic yellow vein virus (BNYVV). The susceptible phenotype developed bright yellow local lesions, whereas the resistant phenotype had symptoms ranging
from no visible lesions to necrotic lesions at the inoculation site. MR1 and MR2 lines had a resistant phenotype depending
on the isolate and the MR0 line was susceptible to all isolates of BNYVV tested. The M8 line was highly susceptible; the virus
spread systemically and caused severe stunting. These plant lines will be useful for distinguishing BNYVV isolates having
different pathogenicities, especially those controlled by RNA3 and/or RNA5. 相似文献