Computed Tomographic Features of Choanal Atresia in a Friesian Foal

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.     

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

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.     

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

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.     

<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>

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.     

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

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.     

Local and landscape effects of agricultural intensification on Carabid community structure and weed seed predation in a perennial cropping system

Context

The effects of agricultural intensification on service-providing communities remain poorly studied in perennial cropping systems. However, such systems differ greatly from annual cropping systems in terms of spatio-temporal dynamics and levels of disturbance. Identifying how land use changes at different scales affect communities and ecosystem services in those habitats is of major importance.

Objectives

Our objectives were to examine the effects of local and landscape agricultural intensification on ground beetle community structure and weed seed predation services.

Methods

We examined the effects of local vegetation management and landscape context on ground beetle community structure and weed seed predation in 20 vineyards of southwestern France in 2013 and 2014. Vineyards were selected along a landscape complexity gradient and experienced different management of local vegetation.

Results

The activity-density of ground beetles decreased with increasing landscape complexity while species richness and evenness remained unchanged. Phytophagous and macropterous species dominated ground beetle communities. Seed predation was positively related to the activity-density of one species, Harpalus dimidiatus, and was not affected by local management or landscape context. We found that within-year temporal diversity in ground beetle assemblages increased with landscape complexity.

Conclusions

Our study shows that increasing the proportion of semi-natural habitats in vineyard landscapes enhances the temporal diversity of ground beetles. However, we also found that measures targeting specific species delivering biological control services are a reasonable strategy if we are to maximize natural pest control services such as weed seed regulation to support crop production and reduce agrochemical use.

     

Plasma lipid lowering effects of wheat germ in hypercholesterolemic subjects

The present study was performed to investigate the possible effects of wheat germ supplementation on lipid metabolism in humans. Ten free-living adult subjects participated in the study. None was obese or diabetic. They all presented an, hypercholesterolemia (from 6.58 to 9.50 mM), associated in 6 over 10 cases to an hypertriglyceridemia (from 1.70 to 5.00 mM). The subjects were studied in three consecutive periods, during which they first were on their usual diet (first week), they then ingested a daily supplement of 30 g wheat germ (4 weeks) and then they returned to their usual basal diet (4 weeks follow-up). Dietary records were obtained for 7 and 3 consecutive days before and during wheat germ supplementation, respectively. Fasting blood samples were taken at the end of each period. After 4 weeks of wheat, germ intake, glycemia did not change while total plasma cholesterol significantly decreased (paired Student'st test,p0.05) from 7.80 to 7.15 mM. LDL and HDL cholesterol values did not show marked changes, but VLDL cholesterol significantly dropped by 40.6%. Thus, the plasma/HDL total cholesterol ratio was significantly lower. Apoprotein B and A1 decreased. In the hypertriglyceridemic subjects, this was accompanied by a significant reduction of plasma triglycerides (1.64 vs. 2.68 mM) and a marked drop of VLDL triglycerides (–51%). Taken as a whole, the present results obtained in humans are very close to those previously obtained in the rat [40] and point out that wheat germ may play a beneficial role in the dietary management of hyperlipidemia.Part of the data communicated in this paper was presented at the Fibre 90 Conference, 17–20 April 1990, Norwich, UK.     

Isolation and properties of lipolysis inhibitory proteins from wheat germ and wheat bran

Proteins inhibiting pancreatic lipasein vitro have been isolated from wheat germ and wheat bran, with relative molecular mass ranging from 24,400 to 27,500. Inhibition of pancreatic lipase by the wheat germ proteins is related to their ability to interact with the emulsified substrate and to hinder the adsorption of the enzyme on the interface. The extent of inhibition depends on the amount of substrate and is independent of the enzyme concentration. Bile salts forming micelles in the concentration range used are able to partially reverse the inhibition of pancreatic lipase by the wheat germ proteins. The nutritional significance of the data obtained is discussed.     

Aluminium chemistry in two contrasted acid forest soils and headwater streams impacted by acid deposition,Vosges mountains,N.E. France

Al chemistry was studied in two acidic watersheds, one with a podzol, the other with an acid brown soil, in the Vosges mountains (N.E. France), by analysing both leaching and centrifugation soil solutions and spring waters over 3 yr. In the podzol, Al was mobilized in the eluvial horizons under the predominant influence of organic acidity, then leached down the profile as organic and F-bound Al. Strong undersaturation with respect to proto-imogolite and imogolite showed that the proto-imogolite theory of podzolization could not apply. Al was transferred from the soil to spring water mostly as Al³⁺ and Al-F. Al³⁺, as well as additional minor species (AlOH²⁺, AlSO₄ ⁺), originated from the redissolution of the top of the spodic horizons under the influence of both soil solution acidity and the occurrence of mobile anions derived from atmospheric deposition. Conversely, in the acid brown soil, Al mobilization was regulated by nitrate and occurred mainly as Al³⁺. Most of Al was retained in the deep soil and only traces of monomeric Al reached spring water. In the podzol eluvial horizons, soil solutions were undersaturated with respect to all relevant mineral phases and their chemical composition agree with the concept of a mobilization of Al from the solid soil organic Al and a control of Al³⁺ activity by complexation reaction with the solid and soluble soil organic matter and F. In the acid brown soil, soil solutions were found to be in equilibrium with natural alunite, and the formation of this mineral, if confirmed, would account for the occurrence of 'open' vermiculites instead of the expected hydroxy-Al interlayered vermiculites. Al solubility control in surface water of both watersheds remains unclear. The Al-F species in both watersheds and the likely control of Al solubility by alunite in the acid brown soil emphasize the influence of acid deposition on Al chemistry in acid watersheds.     

Uptake and nutrient balance of nitrogen,sulfur, and boron for optimal canola production in eastern Canada

Balanced plant nutrition is essential to achieve high yields of canola (Brassica napus L.) and get the best economic return from applied fertilizers. A field study was conducted at nine site‐years across eastern Canada to investigate the effects of nitrogen (N), sulfur (S) and boron (B) fertilization on canola nutrient uptake, nutrient balance, and their relationship to canola yields. The factorial experiment consisted of four N rates of 0 (N0), 50 (N50), 100 (N100), and 150 (N150) kg ha^?1, two S rates of 0 (S0) and 20 (S20) kg ha^?1, and three B treatments of 0 (B0), 2 kg ha^?1 at preplant (B2.0P), and 0.5 kg B ha^?1 foliar‐applied at early flowering stage (B0.5F). Each site‐year used the same experimental design and assigned treatments in a randomized complete block design with four replications. Fertilizer S application greatly improved seed yields at six out of nine site‐years, and the highest N use efficiency was in the N150+S20 treatment. Sulfur application generally increased seed S concentration, seed S removal, and plant total S uptake, while B fertilization mainly elevated straw B concentration and content, with minimal effect on seed yields. At the early flowering stage, plant tissue S ranged from 2.2 to 6.6 mg S g^?1, but the N : S ratio was over or close to the critical value of 12 in the N150+S0 combination at five site‐years. On average across nine site‐years, canola reached a plateau yield of 3580 kg ha^?1 when plants contained 197 kg N ha^?1, 33 kg S ha^?1 and 200 g B ha^?1, with a seed B content of 60 g B ha^?1. The critical N, S, and B values identified in this work and their potential for a posteriori nutrient diagnosis of canola should be useful to validate fertilizer requirements for canola production in eastern Canada.