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Metal behaviour and availability at a contaminated dredge material disposal site within UK waters has been investigated using Diffusive Gradient in Thin films (DGT) passive sampling technology. Three stations representing contrasting history and presence of maintenance dredge disposal, including a control station outside the disposal site, have been studied and depth profiles of fluxes of different metals (Fe, Mn, Pb, Cu, Cd, Cr, Ni, Zn) to the binding gel (Chelex 100) have been derived. Higher flux rates and shallower mobilisation of metals (Mn and Fe) to the binding gel were observed at the disposal stations compared to the control station. Here we describe metal mobilization at different depths, linking the remobilization of Fe2+ and Mn2+ to the sediment (re)supply of other heavy metals of interest with a focus on Cd, Ni and Pb and as they are on the Water Framework Directive (WFD) list of priority substances and OSPAR list of priority pollutants. Results showed that Cd, Pb and Ni exhibited signs of resupply at the sediment-water interface (SWI). There was a potential increased mobilisation and source to the water column of Pb and Ni at the disposal site stations, but there was no Cd source, despite higher total loadings. This information has the potential to improve our current understanding of metal cycles at disposal sites. This work can be used as an indication of likely metal bioavailability and also assist in determining whether the sites act as sources or sinks of heavy metals. This information could assist disposal site monitoring and dredge material licensing.

The aim of the study was to investigate nutritional, physiological and immunological effects of a plant‐derived blend of isoquinoline alkaloids (Sangrovit® Extra) in healthy dogs. Two groups of healthy, adult beagles (N = 10) were tested in a cross‐over experiment, lasting two consecutive three‐week periods. The experimental group received 1.2 g additive/kg feed, according to the recommendation of 10–20 mg/kg live weight per day. The control group received the same feed without additive. Complete blood count, immunological parameters and amino acid concentrations in serum were assessed. Faeces were analysed for short‐chain fatty acids, lactate and ammonium; moreover, their quantity and consistency were determined. Neither feed intake, total apparent nutrient digestibility (crude protein and fat, organic matter, sodium, potassium) were affected by intake of the product. Lymphocyte and monocyte counts were slightly increased in both groups. Elevation was not treatment dependant. IgA, IgG, haptoglobin in serum and flow cytometric phenotyping of peripheral lymphocytes were not affected by alkaloids supplementation. Numerically greater methionine concentrations in blood serum occurred in the experimental group (p = 0.182). Quantity and consistency of faeces and ammonium concentration in faeces were not affected by the additive. Faecal concentrations of short‐chain organic acids differed between groups (acetic acid, % of total SCFA: control group 52.3 ± 5.2 vs. experimental group 57.1 ± 4.5, p = 0.042), lactate concentrations (d‐, l‐ and total) did not. Due to the shift of SCFA proportions in faeces, an effect of isoquinoline alkaloids (IQs) on the metabolic activity of intestinal microbiota is probable. In conclusion, the addition of IQs in the given dose was well tolerated and did not have adverse effects in healthy dogs. [ABSTRACT FROM AUTHOR]

Two feeding trials were conducted to investigate the effects of hydrolyzed (HY) or non-hydrolyzed (NHY) yeast (Kluyveromyces fragilis) in isoenergetic and isonitrogeneous diets in the postweaning period. In experiment 1, a total of 550 unsexed pigs (6.5 ± 0.5 kg BW), weaned at 24 ± 2 d of age, were allocated to five treatment groups, receiving either a control diet (CON) or diets with 1%, 3%, and 5% HY (groups HY1, HY3, and HY5, respectively), or a diet with 3% NHY (group NHY3). In experiment 2, a total of 48 male and female pigs (6.2 ± 0.3 kg BW, weaned at d 25) were allocated to three dietary groups (n = 8 replicates with two pigs) receiving a control diet (CON) or diets with 1% NHY or 1% HY. Eight animals were sacrificed 2 wk after weaning for histological investigations in the jejunum and colon, determination of apparent ileal digestibility (AID) of CP and ether extract (EE), and electrophysiological measurements in the jejunal tissue after addition of carbachol or l-glutamine using Ussing chambers. In experiment 1, different treatments had no significant effect on pig performance, but diet HY1 tended to increase ADG and G:F in wk 2 after weaning (P < 0.1). In experiment 2, diet HY1 increased feed intake in wk 2 (P < 0.05), whereas NHY yeast had no effect on feed intake. Villus height, villus/crypt ratio in jejunum (P < 0.05), and crypt depth in colon (P < 0.01) were increased in group HY1. Crypt depth in jejunum and small intestinal length were not affected by different treatments. The AID of CP and EE tended to increase in group HY1 (P < 0.1) compared with groups CON and NHY. In the Ussing chamber experiments, no changes in basal electrophysiological parameters were observed, and the reactions of the treatment groups to carbachol and l-glutamine were comparable. ADFI was positively correlated with different parameters of intestinal morphology (villus height, villus/crypt ratio, crypt depth in colon, length of small intestine), AID of CP, EE, and performance. The results suggest that a supplementation of 1% HY based on K. fragilis to pig diets may positively influence ADFI and intestinal morphology in pig in the early postweaning period (d 1 to 14). [ABSTRACT FROM AUTHOR]