A spatiotemporal study of bacterial community profiles associated with Atlantic bluefin tuna larvae,Thunnus thynnus L., in three Mediterranean hatcheries     

François‐Joël Gatesoupe  Denis Covès  Aurelio Ortega  Nikos Papandroulakis  Olav Vadstein  Fernando de la Gándara 《Aquaculture Research》2013,44(10):1511-1523

During the first 2 years of larval rearing trials with Atlantic bluefin tuna, survival was a challenging issue. As bacterial colonization of the gut has been shown to play a key role for other species, we studied the profiles of the microbiota associated with individual larvae at different stages in three distant hatcheries. The Bacterial Community Profile (BCP) was quantified based on PCR‐DGGE analyses of partial amplicons from 16S rDNA. Considerable individual variability in BCP was observed before onset of feeding, and the BCP did not show regular fluctuation during ontogenesis. Microalgae were added to the rearing tanks in two of the three hatcheries, but it was not possible to distinguish the effect of location from the effect of algal addition on BCP. In one hatchery, the larvae were reared either with algal addition or in mesocosm, but due to high individual variability, no significant difference in BCP was detected between the two groups. It was hypothesized that this variability was caused by differences in health, physiological status and developmental stage of the larvae. A practical conclusion from the study is the need to analyse a considerable number of individuals to reflect statistically significant differences between the microbial communities associated with rearing groups.  相似文献   

Retrospective evaluation of 155 adult equids and 21 foals with tetanus in Western,Northern, and Central Europe (2000–2014). Part 1: Description of history and clinical evolution          下载免费PDF全文

Gaby van Galen DVM  PhD  DECEIM  DECVECC  Claude Saegerman DVM  PhD  DECVPH  Joke Rijckaert DVM  Helene Amory DVM  PhD  DECEIM  Lara Armengou DVM  PhD  DECEIM  Barbora Bezdekova DVM  PhD  DECEIM  Inge Durie DVM  DECEIM  Rikke Findshøj Delany DVM  Nathalie Fouché DVM  DVM  Laura Haley MVB  Michael Hewetson BVSc  DECEIM  Rene van den Hoven DVM  PhD  DECEIM  Anna Kendall DVM  DECEIM  Fernando Malalana DVM  DECEIM  MRCVS  Jessika Muller Cavalleri DVM  DECEIM  PhD  Tresemiek Picavet DVM  DECEIM  PhD  Katja Roscher DVM  DECEIM  Denis Verwilghen DVM  PhD  DECVS  Meret Wehrli Eser DVM  DECEIM  Cornélie Westermann DVM  PhD  DECEIM  Tim Mair BVSc  PhD  DECEIM 《Journal of Veterinary Emergency and Critical Care》2017,27(6):684-696

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Effects of partial immersion in water on vertical ground reaction forces and weight distribution in dogs     

Levine D  Marcellin-Little DJ  Millis DL  Tragauer V  Osborne JA 《American journal of veterinary research》2010,71(12):1413-1416

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Computed Tomographic Features of Choanal Atresia in a Friesian Foal     

Gaby van Galen  Géraldine Bolen  Denis Verwilghen  Anne-Laure Etienne  Silvia Rabba  Sigrid Grulke  Frederic Billen  Frederic Snaps 《Journal of Equine Veterinary Science》2010

A 3-week-old Friesian colt with a history of respiratory distress since birth was presented to our facility. Results after an endoscopy showed obstruction of the right nasal passage to the nasopharynx. Computed tomography was performed to further characterize this unilateral blockage. The images demonstrated a complete membranous obstruction of the ventral meatus, along with deviation of the vomer bone toward the left side of the nasal cavity. The diagnosis of unilateral choanal atresia was confirmed. This report is the first to describe computed tomographic features of choanal atresia in a foal.  相似文献   

Effects of dredging operations on sediment quality: contaminant mobilization in dredged sediments from the Port of Santos, SP, Brazil     

Ronaldo J. Torres  Denis M. S. Abessa  Fernando C. Santos  Luciane A. Maranho  Marcela B. Davanso  Marcos R. L. do Nascimento  Antonio A. Mozeto 《Journal of Soils and Sediments》2009,9(5):420-432

Background, aim, and scope  

Contaminated sediments are a worldwide problem, and mobilization of contaminants is one of the most critical issues in environmental risk assessment insofar as dredging projects are concerned. The investigation of how toxic compounds are mobilized during dredging operations in the channel of the Port of Santos, Brazil, was conducted in an attempt to assess changes in the bioavailability and toxicity of these contaminants.  相似文献   

Effects of field and landscape variables on crop colonization and biological control of the cabbage root fly Delia radicum     

Céline Josso  Anne Le Ralec  Lucie Raymond  Julia Saulais  Jacques Baudry  Denis Poinsot  Anne Marie Cortesero 《Landscape Ecology》2013,28(9):1697-1715

Agriculture intensification has deeply modified agroecosystems from field to landscape scales. To achieve successful pest control using natural enemies, understanding species interactions over all scales remains a challenge. Using the cabbage root fly as a model, we studied whether field and landscape characteristics influenced colonization and infestation of broccoli fields by the pest and its control by natural enemies. We also determined whether species of different trophic level or host specialization would respond to environmental characteristics at the same spatial extent. During a multiple-species and multiple-spatial extent study in northwestern France, we recorded pest colonization and infestation in 68 fields, collected associated natural enemies and assessed crop damages. In each field, we considered management practices and characterized the surrounding landscape in 50–500 m-wide buffers. Our main findings are that Delia radicum and its main natural enemies respond to both field and landscape characteristics. Semi-natural areas supported both crop colonization by pests and natural enemy action. The pest and its enemies differed in their responses to field or landscape variables. Landscape elements such as field banks favored the movement of the pest while impeding the movement of some natural enemies. Pest pressure did not increase with the neighboring density of Brassica crops. The presence of natural enemies did not reduce crop damage but reduced pest emerging rates. Finally, specialist parasitoids responded to the landscape at larger spatial extents than generalists. These results outline the complexity of improving pest control through landscape management.  相似文献   

Microphytobenthic production estimated by in situ oxygen microprofiling: short-term dynamics and carbon budget implications     

Lionel Denis  Fran?ois Gevaert  Nicolas Spilmont 《Journal of Soils and Sediments》2012,12(10):1517-1529

Purpose

Short-term temporal variability of microphytobenthic primary production is suspected to be of the same magnitude as seasonal variability, but data remain very scarce due to methodological limitations. In this context, a 6-day in situ high-frequency survey was performed in a temperate intertidal mudflat using an automated microprofiling system.

Materials and methods

In situ microphytobenthic primary production was measured using an automated acquisition system for oxygen microprofiles. More than 900 microprofiles, acquired during six consecutive days in April 2008, allowed the establishment of robust relationships between oxygen production and irradiance. Moreover, simultaneous measurements of fluorescence parameters and oxygen microprofiles during two diurnal emersion periods led to significant correlations between relative electron transport rate (rETR) and gross oxygen production (GOP).

Results and discussion

The use of an automated system allowed the estimation of oxygen exchanges during both immersion and emersion periods, and to our knowledge, this is the first study presenting continuous measurements during six consecutive days. The intertidal mudflat studied here was characterized by a maximum net oxygen production of 6.74?mmol?O₂?m^?2?h^?1. Evidence for microphytobenthic migration behavior was observed during several periods and induced important depletion in oxygen production while irradiance remained high. Consequently, estimations of GOP from fitted photosynthesis?Cirradiance curves (P?CI curves) showed an overestimation of 31?% compared to the GOP actually measured during the whole deployment.

Conclusions

This study confirmed that oxygen microsensors may be used to record microphytobenthic primary production, as resulting dynamics agreed with fluorescence data, while production values were in accordance with those presented in the literature. High-frequency microprofiles acquisition may be an easy way to monitor short-term temporal changes in microphytobenthic primary production in order to calculate accurate carbon or oxygen budgets for intertidal areas.  相似文献   

Nature-inspired soluble iron-rich humic compounds: new look at the structure and properties     

Tatiana A. Sorkina  Alexander Yu. Polyakov  Natalia A. Kulikova  Anastasia E. Goldt  Olga I. Philippova  Alina A. Aseeva  Alexey A. Veligzhanin  Yan V. Zubavichus  Denis A. Pankratov  Eugene A. Goodilin  Irina V. Perminova 《Journal of Soils and Sediments》2014,14(2):261-268

Purpose

Humic substances (HS) being natural polyelectrolyte macromolecules with complex and disordered molecular structures are a key component of the terrestrial ecosystem. They have remarkable influence on environmental behavior of iron, the essential nutrient for plants. They might be considered as environmental friendly iron deficiency correctors free of synthetic iron (III) chelates disadvantages. The main goal of this study was to obtain water-soluble iron-rich humic compounds (IRHCs) and to evaluate their efficiency as chlorosis correctors.

Materials and methods

A facile preparation technique of IRHCs based on low-cost and available parent material was developed. The iron-containing precursor (ferrous sulfate) was added dropwisely into alkaline potassium humate solution under vigorous stirring and pH-control. A detailed characterization both of organic and inorganic parts of the compounds was provided, the iron species identification was carried out jointly by EXAFS and Mössbauer spectroscopy. Bioassay experiments were performed using cucumber Cucumis sativus L. as target plants. Plants were grown in modified Hoagland nutrient solution, prepared on deionized water and containing iron in the form of IRHCs. Total iron content in dry plants measured by spectrophotometry after oxidative digestion and the chlorophyll a content determined after acetone extraction from fresh plant were used as parameters illustrating plants functional status under iron deficiency condition.

Results and discussion

The high solubility (up to130 g/l) and iron content (about 11 wt%) of the IRHCs obtained allow considering them to be perspective for practical applications. A set of analytical methods has shown that the main iron species in IRHCs are finely dispersed iron (III) oxide and hydroxide nanoparticles. An application of the precursor solution acidification allows to obtain compounds containing a significant part of total iron (up to 30 %) in the form of partly disordered iron (II–III) hydroxysulphate green rust GR(SO₄ ^2?). Bioavailability of iron from IRHCs was demonstrated using bioassay in cucumber plants grown up on hydroponics under iron deficiency conditions.

Conclusions

The application of iron oxides chemistry for humic substance containing solution was proved to be an effective approach to synthesis of IRHCs. Using bioassay on cucumber plants C. sativus L. under iron deficiency conditions, the efficiency of compounds obtained as chlorosis correctors was demonstrated. Application of water-soluble IRHCs led to significant increase of chlorophyll a content (up to 415 % of the blank) and iron content in plants (up to 364 % of the blank) grown up on hydroponics.  相似文献   

<Emphasis Type="Italic">Streptococcus uberis</Emphasis>-specific T cells are present in mammary gland secretions of cows and can be activated to kill <Emphasis Type="Italic">S. uberis</Emphasis>     

Denis M  Lacy-Hulbert SJ  Buddle BM  Williamson JH  Wedlock DN 《Veterinary research communications》2011,35(3):145-156

The presence, phenotype and function of Streptococcus uberis-specific T cells in the mammary gland secretion (MGS) and blood of cows exposed to S. uberis were assessed. MGS T cells in the udder were purified and incubated with autologous blood monocytes as antigen-presenting cells (APC). Most cows, irrespective of prior S. uberis infection status and lactation status, were shown to have S. uberis-specific T cells both in MGS and in the blood. When cells from a subgroup of cows were studied, it was found that the S. uberis-specific T cells produced high levels of interferon-gamma (IFN-γ), but low levels of interleukin-10 (IL-10). A high percentage of responding T cells were of the CD8 ⁺ memory (CD45RO) subset. T cells from the MGS specific for S. uberis were propagated from animals during the drying off period and expanded in vitro using interleukin-2 (IL-2) and S. uberis antigens. This led to the accumulation of T cells of the CD8 ⁺ subset bearing memory cell markers (CD45A ⁻ , CD45RO ⁺ ), which released high levels of IFN-γ. Four of the five T cell lines derived from the MGS of three animals had substantial direct killing activity towards S. uberis in vitro. It is concluded that there is an emergence of S. uberis-specific bactericidal T cells in the MGS of cows after infection or environmental exposure to S. uberis. Vaccines aimed at activating and expanding this T cell population in the mammary glands of cattle may offer an avenue for the prevention of mastitis caused by S. uberis.  相似文献   

First reports of Trichinella pseudospiralis in wild boars (Sus scrofa) of Italy     

Merialdi G  Bardasi L  Fontana MC  Spaggiari B  Maioli G  Conedera G  Vio D  Londero M  Marucci G  Ludovisi A  Pozio E  Capelli G 《Veterinary parasitology》2011,178(3-4):370-373

Trichinella pseudospiralis is a non-encapsulated species infecting both mammals and birds. In Italy, this parasite was reported only in two night-birds of prey of Central Italy. In January 2010, Trichinella larvae were detected in three wild boars (Sus scrofa) of two regions of Northern Italy by enzymatic digestion. The parasites were identified as T. pseudospiralis by multiplex-PCR. The first infected wild boar was hunted in the Emilia Romagna region and the other two infected wild boars were bred outdoors in a small family farm of the Friuli Venezia Giulia region. These new epidemiological data reinforce the role of the wild boar as the main reservoir of T. pseudospiralis in Europe.  相似文献