Efficacy of a mycotoxin binder against dietary fumonisin, deoxynivalenol, and zearalenone in rats

It was hypothesized that a mycotoxin binder, Grainsure E, would inhibit adverse effects of a mixture of fumonisin B1, deoxynivalenol, and zearalenone in rats. For 14 and 28 days, 8-10 Sprague-Dawley rats were fed control diet, Grainsure E (0.5%), toxins (7 μg fumonisin B1/g, 8 μg of deoxynivalenol/g and 0.2 μg of zearalenone/g), toxins (12 μg of fumonisin B1/g, 9 μg of deoxynivalenol/g, and 0.2 μg of zearalenone/g + Grainsure E), or pair-fed to control for food intake of toxin-fed rats. After 28 days, decreased body weight gain was prevented by Grainsure E in toxin-fed female rats, indicating partial protection against deoxynivalenol and fumonisin B1. Two effects of fumonisin B1 were partly prevented by Grainsure E in toxin-fed rats, increased plasma alanine transaminase (ALT) and urinary sphinganine/sphingosine, but sphinganine/sphingosine increase was not prevented in females at the latter time point. Grainsure E prevented some effects of fumonisin B1 and deoxynivalenol in rats.     

Zinc distribution and speciation within rocket plants (Eruca vesicaria L. Cavalieri) grown on a polluted soil amended with compost as determined by XRF microtomography and micro-XANES

Zinc distribution and speciation within different organs (root, petiole, and leaf) of the edible plant Eruca vesicaria L. Cavalieri were determined using synchrotron microbeam X-ray techniques (XRF microtomography and mu-XANES) for plants grown in polluted soil with or without compost amendment. Data on soil derived from different extraction procedures and using mu-XANES analyses on rhizospheric soil indicated that compost amendment did not significantly influence the Zn speciation and availability in soil. However, major differences were observed within the plants. Plants grown in the presence of compost were able to partly block zinc immediately outside the root endodermis in the form of zinc-phytate, while a smaller Zn fraction was allowed to xylem transport as zinc-citrate. In the leaves, zinc was largely excluded from leaf cells, and about approximately 50% was in the form of phosphate precipitates, and the other 50% was complexed by cysteine and histidine residues. The reported data provide new information concerning the mechanisms of zinc tolerance in E. vesicaria L. Cavalieri, a very common edible plant in Mediterranean regions, and on the role of compost in influencing the molecular strategies involved in zinc uptake and detoxification.     

Metabolite production during in vitro colonic fermentation of dietary fiber: analysis and comparison of two European diets

Metabolite production and antioxidant released during colonic fermentation of naturally occurring dietary fiber (DF) from two European diets (Mediterranean and Scandinavian) were determined. With this aim, DF and associated components were isolated from both whole diets, as well as from cereals and fruits and vegetables comprising the diets. DF was used as substrate for colonic fermentation in a dynamic in vitro model of the colon, samples were collected, and fermentation metabolites were analyzed. Statistical differences between samples were observed in the concentrations of short-chain fatty acids and ammonia and in the ratio acetate/propionate/butyrate. Whole grain cereal DF generated a larger amount of propionate than refined flour cereal DF. Fruit and vegetable DF generated higher amounts of butyrate than cereal DF. Most antioxidant compounds were released from DF during in vitro colonic fermentation. It is concluded that different sources of DF may play a specific role in health maintenance mediated by metabolites produced during colonic fermentation.     

Sediment Load in Runoff Under Laboratory and Field Simulated Rainfall

Soil erosion is one of the most important problems in the Loess Plateau of China affecting sustainable agriculture. Near Luoyang (Henan Province, China), field plots were constructed to measure soil erosion rates under conventional tillage practices using field-simulated rainfall. Field rainfall experiments were carried out to compare previous results from laboratory rainfall simulations on the same soil for interrill conditions. Although in the laboratory experiments, a strong correlation was found between the stream power of the runoff water and the unit sediment load, this sediment transport equation overestimated the field rainfall simulation results. Another sediment transport equation derived by Nearing et al. for rill erosion was in better agreement with the results of the field experiments, although it also overestimated these values. The measured sediment load values during the field rainfall simulations were also lower than those found during field experiments on the same soil but with a loosened surface layer. This difference indicates the importance of soil physical condition of surfce like soil structure and aggregate size, which may contribute to the discrepancy between the field and laboratory experiment results.     

Beach nourishment: an ecologically sound coastal defence alternative? A review

• 1. Even though beach nourishment is generally considered as an environment‐friendly option for coastal protection and beach restoration, sizeable impacts on several beach ecosystem components (microphytobenthos, vascular plants, terrestrial arthropods, marine zoobenthos and avifauna) are described in the literature, as reviewed in this paper.
• 2. Negative, ecosystem‐component specific effects of beach nourishment dominate in the short to medium term, with the size of the impact being determined by (1) activities during the construction phase, (2) the quality and (3) the quantity of the nourishment sand, (4) the timing, place and size of project, and (5) the nourishment technique and strategy applied. Over the long term the speed and degree of ecological recovery largely depend on the physical characteristics of the beach habitat, mainly determined by (1) sediment quality and quantity, (2) the nourishment technique and strategy applied, (3) the place and the size of nourishment and (4) the physical environment prior to nourishment.
• 3. The limited information available on indirect and cumulative ecological effects indicates that these effects cannot be neglected in an overall impact assessment. Hence, for ecologically good practice of beach nourishment it is advised (1) to choose nourishment sands with a sediment composition comparable to that of the natural sediment, (2) to avoid short‐term compaction by ploughing immediately after construction, (3) to execute the nourishment in a period of low beach use by birds and other mobile organisms, (4) to choose a number of smaller projects rather than a single large nourishment project and (5) to select the nourishment technique with respect to the local natural values.
• 4. In order to allow an objective, scientifically sound, ecological adjustment of future nourishments, research should aim at (1) taking into account the full sandy beach ecosystem, (2) avoiding strategic imperfections in experimental design and (3) elucidating the biological processes behind impact and recovery of all ecosystem components.

Copyright © 2006 John Wiley & Sons, Ltd.     

CT diagnosis of occipital condyle fracture in a dog presented for severe cervical hyperesthesia

A 9-month-old male entire Doberman Pinscher presented with acute onset of severe cervical hyperesthesia after a fall. Neurological examination revealed a normal gait with low head carriage and severe cervical hyperesthesia. A CT scan of the cervical vertebral column revealed the presence of a comminuted fracture at the dorsomedial aspect of the right occipital condyle and sclerosis of the underlying bone. Medical management was initiated consisting of an external bandage, strict rest, and pain medication. Due to the lack of clinical improvement, the dog was euthanized 2 months after diagnosis. Histopathology of the lesion was compatible with a healing fracture.     

Landscape resistance and American marten gene flow

Landscape heterogeneity can influence animal dispersal by causing a directional bias in dispersal rate, as certain landscape configurations might promote, impede, or prevent movement and gene flow. In forested landscapes, logging operations often contribute to heterogeneity that can reduce functional connectivity for some species. American martens (Martes americana) are one such species, as they are considered specialists of late-seral coniferous forests. We assessed marten gene flow to test the hypothesis that habitat management has maintained landscape connectivity for martens in the managed forests of Ontario, Canada. We genotyped 653 martens at 12 microsatellite loci, sampled from 29 sites across Ontario. We expected that if forest management has an effect on marten gene flow, we would see a correlation between effective resistance, estimated by circuit theory, and genetic distance, estimated by population graphs. Although we found a positive relationship between effective resistance and genetic distance (Mantel r = 0.249, P < 0.001), marten gene flow was better described by isolation by Euclidean distance (Mantel r = 0.410, P < 0.001). Our results suggest that managed forests in Ontario are well connected for marten and neither impede nor promote marten gene flow at the provincial scale.     

Regional distribution of technetium-99m-ECD in the canine brain: Optimal injection–acquisition interval in adult beagles

Changes in the regional cerebral blood flow (rCBF), a measure for regional cerebral metabolism, have been reported in dogs suffering from behavioral problems like shadow chasing, anxiety, and compulsive disorders. The rCBF can be measured with single-photon emission computed tomography. Although the acquisition is performed afterward under general anesthesia, the distribution of technetium-99m-ethylene-diylbis-l-cysteine diethyl ester or ^99mTc-ECD, a tracer which becomes trapped in the brain, represents the rCBF at the moment the tracer was administered to the awake dog (fixed or frozen image). The aim of this study was to examine the in vivo stability and the duration of the fixed distribution of this tracer in the canine brain. Three acquisitions were performed 15, 40, and 65 minutes after tracer injection. Total counts and perfusion indices, normalized to the total brain counts and to the cerebellum, were calculated (semiquantification). At T65, significant differences in the perfusion indices occurred compared with at T15. This study shows that in dogs, regional differences in the clearance of ^99mTc-ECD result in significant alterations of the perfusion indices from 65 minutes onward after tracer injection. Therefore, it is recommended to start the acquisition between 15 and 40 minutes postinjection in dogs when this technique is used for studying rCBF alterations in dogs with behavioral problems.     

Devriesea agamarum causes dermatitis in bearded dragons (Pogona vitticeps)

Devriesea agamarum is frequently isolated from dermatitis in lizards, notably from cheilitis in spiny tailed lizards (genus Uromastyx). It was the aim of the present study to assess the role of this bacterium as a causative agent of dermatitis by fulfilling Koch's postulates. First, its association with diseased lizards was demonstrated. The bacterium was isolated from several, mainly desert dwelling squamate species showing symptoms of dermatitis and/or septicaemia. The affected lizards mainly belonged to the family of the Agamidae (genera Pogona, Uromastyx, Agama) and in one case to the Iguanidae (genus Crotaphytus). Secondly, the occurrence of D. agamarum in 66 clinically healthy bearded dragons, 21 clinically healthy Uromastyx species and 40 squamate eggshells was studied. The bacterium was isolated from the oral cavity of 10 bearded dragons but from none of the healthy Uromastyx species. Hence D. agamarum was found to be part of the oral microbiota in Pogona vitticeps. Finally, bearded dragons (P. vitticeps) were experimentally inoculated with D. agamarum by direct application of a bacterial suspension on intact and abraded skin. At the scarified skin of all inoculated lizards, dermatitis was induced from which D. agamarum was re-isolated. In conclusion, D. agamarum is a facultative pathogenic bacterium, able to cause dermatitis in agamid lizards when the integrity of the skin is breached.     

Characterization of the in vitro adhesion of Actinobacillus pleuropneumoniae to swine alveolar epithelial cells

Actinobacillus pleuropneumoniae biovar 1 serotypes 2, 5a, 9 and 10 strains were tested for their ability to adhere to alveolar epithelial cells in culture. For the serotypes 5a, 9 and 10 strains, optimal adherence was observed after growth of bacterial cells in a NAD-restricted medium (0.001% NAD). This condition was also associated with the expression of a 55 kDa outer membrane protein (OMP) and of fimbriae. For the serotype 2 strain, adherence and expression of fimbriae and a 55 kDa OMP was less influenced by the growth conditions. The N-terminal amino acid sequence of the 55 kDa OMP had no homology with any known sequence, suggesting that it is an as yet unknown protein. Adherence capabilities were significantly reduced following treatment of the bacteria with proteolytic enzymes or heat. These findings suggest that proteins are involved in adhesion. The hydrophobic bond-breaking agent tetramethylurea was unable to inhibit the adherence of A. pleuropneumoniae to alveolar epithelial cells. Treatment of the bacteria with sodium metaperiodate resulted in lower adhesion scores for the serotypes 2 and 9 strains but the inhibition of adhesion was clearly lower than after treatment with proteolytic enzymes. This indicates that, besides proteins, carbohydrates might also be involved in adhesion of A. pleuropneumoniae to alveolar epithelial cells. The finding that inhibition of adhesion was very high when bacteria were treated with a combination of sodium metaperiodate and pronase also suggests that more than one adhesin is involved.