Tissue fluoride accumulation and kidney lesions in freshwater‐reared Atlantic salmon (Salmo salar) fed with high dietary fluoride concentrations

Antarctic krill (Euphausia superba) and other marine zooplankton may contain high levels of fluoride. The aim of the present experiment was to determine whether dietary fluoride from Antarctic krill at levels similar to the old and the new EU allowable limits in fish feeds (150 and 350 mg kg^?1) would induce kidney lesions in freshwater‐reared Atlantic salmon (Salmo salar). In addition to the diets containing krill, two high‐sodium fluoride (NaF) diets (1500 and 3500 mg kg^?1) were used to investigate the effect on growth, feed intake, faecal excretion of minerals and accumulation of fluoride in various tissues. No major effects on growth or feed intake were observed. A higher proportion of the ingested fluoride was absorbed in salmon fed with the NaF diets compared with fish fed with krill shell diets. Fluoride accumulated in liver, kidney and especially bone. Faecal excretion of calcium and magnesium was higher for the NaF‐fed fish compared with fish fed with the control and krill shell diets, whereas the levels of these minerals in plasma were unaffected. Dietary fluoride from krill shells did not induce kidney lesions. One‐third of the salmon fed with the highest NaF diet showed signs of crystal formation within the distal tubules and/or collecting ducts in the kidney.     

The effect of food quality on glycogen content,the fatty acid profile and winter mortality in cultivated oyster spat (Ostrea edulis)

Winter mortality in hatchery reared oyster spat (Ostrea edulis) that received three different diets during the summer period was investigated. Oysters fed a natural type diet had a winter mortality of 18.3 ± 6.3% while oysters fed cultivated algae (a mixture of Tetraselmis suecica, Isochrysis galbana and Chaetoceros muelleri) had a mortality of 73.0 ± 9.7%. A group of oysters fed a mix between the two diets had a mortality of 54.7 ± 10.6%. Tissue samples were taken at the start of the experiment, after the summer period and after the winter period in order to determine growth and the content of glycogen and fatty acids. The glycogen content decreased for all groups during the winter but the decrease was highest in oysters fed the natural diet. This group also contained the largest variety of fatty acids, but there was no difference in the content of the essential fatty acids EPA, DPA and DHA between the groups. It is concluded that transplantation of spat to the sea in spring and early summer may reduce winter mortality since the feeding period on a more varied natural algal diet is prolonged compared to transplantation of spat later in the season.     

Nitrogen uptake,nitrate leaching and root development in winter‐grown wheat and fodder radish

Early seeding of winter wheat (Triticum aestivum L.) has been proposed as a means to reduce N leaching as an alternative to growing cover crops like fodder radish (Raphanus sativus L.). The objective of this study was to quantify the effect of winter wheat, seeded early and normally, and of fodder radish on N dynamics and root growth. Field experiments were carried out on a humid temperate sandy loam soil. Aboveground biomass and soil inorganic N were determined in late autumn; N uptake and grain yield of winter wheat were measured at harvest. Nitrate leaching was estimated from soil water samples taken at 1 m depth. Root growth was measured late autumn using the core break and root washing methods. Winter wheat root growth dynamics were followed during the growing season using the minirhizotron method. The 2013–2014 results showed that early seeding of wheat improved autumn growth and N uptake and reduced N leaching during the winter compared with the normal seeding time. Early‐seeded wheat (WW_early) was, however, not as efficient as fodder radish at reducing N leaching. Proper establishment of WW_early was a prerequisite for benefiting from early seeding, as indicated by the 2012–2013 results. Early seeding improved root growth throughout the 2013–2014 growing season compared with normal seeding time, but had no significant effect on crop grain yield. Our results indicate the potential of using early seeding as a tool to limit drought susceptibility and increase nutrient uptake from the subsoil.     

Comparative Nutrient Digestibility in Blue Foxes (Alopex lagopus) and Mink (Mustela vison) Fed Diets with Diverging Fat: Carbohydrate Ratios

Abstract

Nutrient digestibilities were evaluated in comparative experiments with blue foxes and mink by using six diets differing in fat:carbohydrate (F:C) ratios. In mink, apparent digestibilities of N and amino acids decreased with decreasing F:C ratio. N digestibility, and most amino acid digestibilities, were higher in blue foxes than in mink (P < 0.01). Fat digestibility in mink, but not in blue foxes, declined as the F:C ratio decreased (P < 0.05). Fat digestibility was higher in blue foxes than in mink (P < 0.05). Carbohydrate digestibility was not affected by the F:C ratio, but high levels of carbohydrates were digested more completely by foxes than by mink. The use of mink digestibility values in feed evaluations for blue foxes will consequently underestimate digestibility. Thus, to evaluate feed correctly, separate digestibility determinations should be made for mink and foxes.     

Economic values for lean meat and fat efficiency in Norwegian Landrace nucleus pig population

A profit function was developed to estimate economic values for new efficiency traits for fattening pigs in Norwegian Landrace. These traits were lean meat efficiency (LME) and fat efficiency (FE). LME and FE described how much feed the animal used to produce 1?kg lean meat and fat as a deviation from the mean. Both traits were derived from analysing total feed consumption in a random regression model which included lean meat and fat content of the carcass (FC) as random covariates. In addition, economic values and breeding values were calculated for days from 40 to 100/120?kg live weight (DAYS), lean meat percentage (LMP) and FC. To compare LME and FE with total feed intake (FI), two indexes were constructed. One index included LME, FE, DAYS, LMP and FC and was referred to as breeding goal A and one index included FI, LMP and DAYS and was referred to as breeding goal B. The standardized economic values for LME and FE were 8.9 and 2.9 EUR/σ_a, respectively. There was a larger variation in the index for breeding goal A (SD?=?5.65) than B (SD?=?3.97). The results suggested that the two efficiency traits had an economic importance in pork production and that there was a potential for increased genetic gain in profit by using breeding goal A compared to breeding goal B.     

Biochemical and structural factors contributing to seasonal variation in the texture of farmed Atlantic halibut (Hippoglossus hippoglossus L.) flesh

Factors contributing to the texture of fish flesh, including pH, water content, density of fast muscle fibers, and the concentration of collagen and hydroxylysyl pyridinoline (PYD) cross-links, were investigated post-rigor in commercially farmed Atlantic halibut (Hippoglossus hippoglossus L.). The fish was sampled every quarter for a 12 month period from May 2004 to May 2005. Hydroxyproline (HYP) as a measure of collagen and PYD were determined using a high-performance liquid chromatography (HPLC) method. An ANCOVA model with fork length and season as covariates were used to explore the seasonal effects on texture, pH, muscle fiber density, alkaline-insoluble collagen (a-i HYP), alkaline-soluble collagen (a-s HYP), and PYD cross-links. A multiple linear regression (MLR) showed that the most important factors contributing to texture were PYD>water (%)>a-i HYP>fiber density, while pH and a-s HYP did not show any correlation to texture. The contribution of fast muscle fiber density to texture was found to vary between sexes and with the season, contributing more in males and in the spring. The most important parameter affecting texture was PYD, explaining 64% (p<0.001) of the total variation in a linear regression analysis. It is concluded that cross-linking processes are of great importance for the rigidity and strength of the collagen in Atlantic halibut flesh. Farmed halibut should be harvested in the fall or early winter when texture and nutrition are good to obtain optimal quality.     

Comparing the performance of cereal varieties in organic and non-organic cropping systems in different European countries

Top ranking varieties are tested in multiple environments before and after registration in order to assess their value for cultivation and use (VCU testing). Recently, interest has increased in obtaining varieties specifically adapted to organic farming conditions. This raised the question if an independent system of trials may be required for this purpose. To help answering this question, through the exchange network of European cereal researchers SUSVAR (), a number of data sets of agronomic traits from barley, wheat and winter triticale, from trials performed in Denmark, Sweden, The Netherlands, France, Switzerland, UK and Germany, were made available and analysed using an approach based on mixed models involving parameters describing genetic correlation between the two types of experiments, i.e., organic and non-organic (high or low input). Estimated variance components and correlations were used to evaluate response to selection and index selection. The response to index selection was analysed as a function of the fraction of available trials assigned to the organic system. The genetic correlations were interpreted in terms of ranking agreement. We found high genetic correlations between both systems for most traits in all countries. Despite high genetic correlations, the chances of very good agreement in observed rankings were moderate. Combining information from both organic and non-organic systems is shown to be beneficial. Further, ignoring information from non-organic trials when making decisions regarding performance under organic conditions is a sub-optimal strategy.     

Transport of volatile chlorinated hydrocarbons in unsaturated aggregated media

Transport of volatile hydrocarbons in soils is largely controlled by interactions of vapours with the liquid and solid phase. Sorption on solids of gaseous or dissolved compounds may be important. Since the contact time between a chemical and a specific sorption site can be rather short, kinetic or mass-transfer resistance effects may be relevant. An existing mathematical model describing advection and diffusion in the gas phase and diffusional transport from the gaseous phase into an intra-aggregate water phase is modified to include linear kinetic sorption on gas-solid and water-solid interfaces. The model accounts for kinetic mass transfer between all three phases in a soil. The solution of the Laplace-transformed equations is inverted numerically. We performed transient column experiments with 1,1,2-Trichloroethane, Trichloroethylene, and Tetrachloroethylene using air-dry solid and water-saturated porous glass beads. The breakthrough curves were calculated based on independently estimated parameters. The model calculations agree well with experimental data. The different transport behaviour of the three compounds in our system primarily depends on Henry's constants.     

Assessment of seafood processing wastes as alternative sources of Selenium in plant production

Abstract

In some parts of the world, the soil selenium (Se) content is too low to ensure the Se level recommended for human or animal consumption in the crops produced. In order to secure a desired concentration of Se in crops, Se has been applied as mineral fertilizer to agricultural fields. Since only a minor part of the inorganic Se applied is utilized by plants and small increases in Se concentrations in, e.g., drinking water, may be toxic, the method is somewhat controversial. As an alternative to Se-enriched mineral fertilizer, different seafood-processing wastes have been examined as a source for Se in crop production. Both in greenhouse pot experiments and field trials the Se in seafood waste was not plant-available during the first growing season. There was no significant difference between the Se concentration in wheat growing in soil without added Se and in soil receiving Se from seafood waste in amounts ranging from 0.9 to 9 g ha^?1. Neither was any residual effect of Se in seafood waste seen during a second year growth period. Thus, seafood-processing waste cannot be regarded as a potential source of Se in crop production. Possible mobilization of formerly applied Se, as seafood-processing waste or Se enriched mineral fertilizer due to changes in soil redox conditions were examined in a leaching experiment. The mobility of formerly applied Se was generally very low, but the results indicated that under permanently wet soil conditions leaching of Se may occur in plant dormant periods in soils with low organic matter content and high pH.     

Anthocyanins in berries of ribes including gooseberry cultivars with a high content of acylated pigments

Consumption of berries from various sources including the genus Ribes has been associated with diverse potential health benefits. The 14 examined cultivars of European gooseberry (R. grossularia L.) contained in various proportions the 3-glucoside (3), 3-rutinoside (4), 3-xyloside (7), 3-O-beta-(6' '-E-caffeoylglucopyranoside) (8), and 3-O-beta-(6' '-E-p-coumaroylglucopyranoside) (10) of cyanidin and the 3-rutinoside (6) and 3-glucoside of peonidin (5). Pigments 3, 4, delphinidin 3-rutinoside (2), delphinidin 3-glucoside (1), and minor amounts of 6, 7, and 10 were found in red flowering currant (R. sanguineum Pursh). Golden currant (R. aureum Pursh) contained 3, 4, and trace amounts of 1, 6, and 7, while alpine currant (R. alpinum L.) contained 3, 4, and trace amounts of 10. The major anthocyanins in two cultivars of jostaberries (R. x nidigrolaria Bauer), 1-4, 8, and 10, reflected that this hybrid contained the major anthocyanins of both parents, black currant and gooseberry. This is the first complete identification of 8 and the ring size of the sugar of 10. Pigment 9 was tentatively identified as cyanidin 3-(6' '-Z-p-coumaroylglucoside). This new pigment occurred in minor amounts (<2%) in all R. grosssularia and R. x nidigrolaria cultivars. No commercially available berries have been reported to contain such high proportions of aromatic acylated anthocyanins as found in the gooseberry cultivars "Sams?", "Hinnom?ki Red", "Taastrup", "Lofthus", and "Glendal", which are in this context the most obvious candidates for consumption, colorant, and breeding programs.