Mortality factors, environmental contaminants, and parasites of white-tailed sea eagles from Greenland

Twelve white-tailed sea eagles (Haliaeetus albicilla groenlandicus) found dead between 1997 and 2000 in Greenland were examined to investigate the health status, including the causes of death and the burden of organochlorine contaminants and potentially toxic heavy metals. The determined causes of death were unspecific trauma (n = 6), lead poisoning (n = 2) with 36 and 26 ppm lead in the liver tissue, infectious diseases (n = 1), injuries sustained during intraspecific conflict (n = 1), and gunshot (n = 1). One lead poisoned eagle had a single lead shot pellet in its gizzard. No diagnosis could be made in one case because of decomposition of the carcass. Four of the investigated eagles were injured with lead shot or bullet fragments; one of the birds was killed with about 69 lead shots. Levels of organochlorine pesticides, polychlorinated biphenyls, mercury, and cadmium in organs were moderate. The parasite fauna consisted of one coccidian and three helminth species. The acanthocephalas Profiliocollis botulus and Corynosoma suduche as well as the nematode Stegophorus stellaepolaris are all new records for the white-tailed sea eagle.     

Serological evidence of continuing high Usutu virus (Flaviviridae) activity and establishment of herd immunity in wild birds in Austria

Usutu virus (USUV), family Flaviviridae, has been responsible for avian mortality in Austria from 2001 to 2006. The proportion of USUV-positive individuals among the investigated dead birds decreased dramatically after 2004. To test the hypothesis that establishment of herd immunity might be responsible, serological examinations of susceptible wild birds were performed. Blood samples of 442 wild birds of 55 species were collected in 4 consecutive years (2003--2006). In addition, 86 individuals from a birds of prey rehabilitation centre were bled before, at the peak, and after the 2005 USUV transmission season in order to identify titre dynamics and seroconversions. The haemagglutination inhibition test was used for screening and the plaque reduction neutralization test for confirmation. While in the years 2003 and 2004 the proportion of seropositive wild birds was <10%, the percentage of seroreactors raised to >50% in 2005 and 2006. At the birds of prey centre, almost three quarters of the owls and raptors exhibited antibodies before the 2005 transmission season; this percentage dropped to less than half at the peak of USUV transmission and raised again to almost two thirds after the transmission season. These data show a from year to year continuously increasing proportion of seropositive wild birds. The owl and raptor data indicate significant viral exposure in the previous season(s), but also a number of new infections during the current season, despite the presence of antibodies in some of these birds. Herd immunity is a possible explanation for the significant decrease in USUV-associated bird mortalities in Austria during the recent years.     

Top down preselection using marker assisted estimates of breeding values in dairy cattle

Top down preselection of young bulls before entering progeny testing has been proposed as a practicable form of marker‐assisted selection (MAS), especially in dairy cattle populations with large male paternal half‐sib families. Linkage phase between the superior (Q) and the inferior (q) QTL alleles of heterozygous sires (Qq at the QTL) with informative markers is established within each paternal half‐sib family and may be used for selection among grand‐progeny. If, additionally to sires, bulldams are also genotyped and data from consecutive generations are used, then a marker‐assisted best linear unbiased prediction (MA‐BLUP) model can be employed to connect the information of all generations and families of a top down design, and to select across all families. A customized ‘augmented’ sire model (with sires and dams of sires as random effects) is introduced for this purpose. Adapted formulae for the mixed model equations are given and their equivalence to a corresponding animal model and to a certain variant of previously proposed reduced animal models is shown. The application of the augmented sire model in MA‐BLUP estimation from daughter‐yield deviations and effective daughter contributions is presented.     

Classification of German white wines with certified brand of origin by multielement quantitation and pattern recognition techniques

A procedure is proposed for the determination of the authenticity of white wines from four German wine-growing regions (Baden, Rheingau, Rheinhessen, and Pfalz) based on their content of some major, trace, and ultratrace elements. One hundred and twenty-seven white wine samples possessing a certificate of origin, all of the 2000 vintage, were analyzed. The concentrations of 13 elements (Li, B, Mg, Ca, V, Mn, Co, Fe, Zn, Rb, Sr, Cs, and Pb) were determined in wine diluted 1:20 by sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). Indium was routinely used as internal standard. Supervised pattern recognition techniques such as discriminant analysis and classification trees were applied for the interpretation of the data. A quadratic discriminant analysis (QDA) allowed the four regions to be discriminated with 83% accuracy when using only eight variables (Li, B, Mg, Fe, Zn, Sr, Cs, and Pb), and the prediction ability for classifying new samples was 76%. By use of a second method, a decision tree, the classification of samples coming from the four regions could be performed with an accuracy of 84% when only four elements were used: Li (very low in samples from Baden), Zn (abnormally low in the samples from the Rheingau), and Mg and Sr (both important for the differentiation between Pfalz and Rheinhessen samples). For this method, the prediction ability was only 74% in the identification of unknown samples. The robustness of the QDA model was not good enough, and therefore the tree is better recommended for the classification of new wine samples from these areas of German wine production.     

Absorption, translocation and metabolism of metamitron in Chenopodium album

BACKGROUND: In recent years, common lambsquarters (Chenopodium album L.) populations from sugar beet fields in different European countries have responded as resistant to the as‐triazinone metamitron. The populations have been found to have the same D1 point mutation as known for atrazine‐resistant biotypes (Ser₂₆₄ to Gly). However, pot experiments revealed that metamitron resistance is not as clear‐cut as observed with triazine resistance in the past. The objectives of this study were to clarify the absorption, translocation and metabolic fate of metamitron in C. album. RESULTS: Root absorption and foliar absorption experiments showed minor differences in absorption, translocation and metabolism of metamitron between the susceptible and resistant C. album populations. A rapid metabolism in the C. album populations was observed when metamitron was absorbed by the roots. The primary products of metamitron metabolism were identified as deamino‐metamitron and metamitron‐N‐glucoside. PABA, known to inhibit the deamination of metribuzin, did not alter the metabolism of metamitron, and nor did the cytochrome P450 inhibitor PBO. However, inhibition of metamitron metabolism in the presence of the cytochrome P450 inhibitor ABT was demonstrated. CONCLUSION: Metamitron metabolism in C. album may act as a basic tolerance mechanism, which can be important in circumstances favouring this degradation pathway. Copyright © 2011 Society of Chemical Industry     

Investigations into shaking mink syndrome: an encephalomyelitis of unknown cause in farmed mink (Mustela vison) kits in Scandinavia.

An apparently novel neurological disease clinically characterized by shaking, tremors, seizures, staggering gait, and ataxia was first observed in farmed mink kits in Denmark in 2000 and subsequently in Sweden, Denmark, and Finland in 2001, and again in Denmark in 2002. Lymphoplasmacytic encephalomyelitis was found in the affected kits. The lesions were most severe in the brainstem and cerebellum and consisted of neuronal degeneration and necrosis, neuronophagia, focal and diffuse gliosis, perivascular cuffs formed by lymphocytes, plasma cells and macrophages, and segmental loss of Purkinje cells. Testing was conducted to determine the cause of the disease, including general virological investigations (virus culture, negative-staining electron microscopy, immunoelectron microscopy, polymerase chain reaction for herpesviruses, adenoviruses, pestiviruses, and coronaviruses), tests for specific viral diseases (canine distemper, Borna disease, Louping ill, West Nile virus infection, tick-borne encephalitis, Aleutian disease), tests for protozoa (Toxoplasma gondii, Neospora caninum, Encephalitozoon cuniculi), bacteria (general culture, listeria, Clamydophila psittaci), and intracerebral inoculation of neonatal mice. The results of all these investigations were negative. One group of 3 mink kits inoculated intracerebrally with brain homogenate of affected mink developed clinical signs and histological lesions similar to those observed in naturally infected mink. Based on the histopathological features, it is postulated that the disease is caused by a yet unidentified virus.     

Screening for nutritive peptides that modify cholesterol 7alpha-hydroxylase expression

Bioactive peptides with a variety of effects have been described from several nutritive proteins. They exhibit antimicrobial, blood-pressure lowering, antithrombotic, immunomodulatory, and cholesterol-modulating effects. In this study, we have examined whether peptides derived from food proteins might influence bile acid synthesis. A reporter gene cell line that carries a cholesterol 7alpha-hydroxylase promoter fragment fused to firefly luciferase ( cyp7a-luc) was used to screen for nutritive peptides affecting cyp7a expression, the enzyme catalyzing the rate-limiting step in bile acid synthesis. Proteolytic hydrolysates were prepared from soy protein and bovine casein with pepsin, trypsin, chymotrypsin, and elastase and size fractionated using ultrafiltration. Several bioactive hydrolysates could be identified that inhibited luciferase expression. Also, an activation of kinase (AKT, ERK, p38-MAPK) signaling could be observed. Selected hydrolysates were further fractionated by reversed-phase HPLC. Bioactive HPLC-fractions were obtained from casein but not from soy hydrolysates; however, activity could not be recovered in single peak fractions. Peptides in such fractions were identified by mass spectrometry. Five selected peptides from alpha S1-casein present in active fractions were synthesized, but none of these showed activity in the cyp7a-luc screening system. However, two of them activated MAP-kinase signaling similar to the hydrolysates, which suggests, that these peptides are involved in cyp7a regulation by the casein hydrolysates.     

The influence of surfactants applied by sewage sludge on the behaviour of Atrazine and PAHs in semiarid soils

The effect of two surfactants applied via sewage sludge: LAS (linear Alkylbenzenesulfonate) and Nonylphenol as a metabolite of Nonylphenol ethoxylate, on PAHs and Atrazine mobility was investigated under semiarid soil conditions in a Vertisol and a Gypsisol treated with sewage sludge. In both cases the surfactants promoted the leachability of Atrazine only moderately compared to the untreated plot. PAHs were leached from the surface layer (0–20 cm) into 20–50 cm layer during the three month test period. Relatively higher leaching was observed in the sandy Gypsisol. Atrazine was leached only in the clayrich Vertisol where the surfactants were present longer than in the plot with sandy Gypsisol.     

The effect of the function type for describing the soil buffer power on calculated ion transport to roots and nutrient uptake from the soil

The relationship between amount of a nutrient in soil and its concentration in solution, the buffer curve, is usually non‐linear. However, most models that calculate nutrient transport in the soil and nutrient uptake by the plant often assume a linear buffer curve because of simpler programming. In this paper a model is presented that uses the Freundlich function to describe the non‐linear buffer curve in the soil. It has been shown that calculated uptake and depletion curves were not influenced by the shape of the buffer curve. In a sensitivity analysis the buffer capacity, soil solution concentration, soil water content, soil impedance factor, maximum influx and the curvature of the Freundlich function were varied and the influence on calculated uptake was studied. The buffer capacity in general had a minor influence and the linearity or non‐linearity of the buffer capacity had under no circumstances an influence on calculated uptake. Thus, the use of a linear buffer curve in transport models does not lead to a significant error in the results.     

Influence of soil pH and contents of organic carbon and clay on the volatilization of [14C]fenpropimorph after application to bare soil

The behaviour of the morpholine fungicide fenpropimorph applied to soil was investigated in a laboratory chamber. The volatility and metabolism of a ¹⁴C-labelled fenpropimorph formulation (Corbel^®) was studied after application to three soils (sandy loam, loamy clay and loamy sand), simulating a four-day weather scenario in the volatilization chamber. Additional experiments were conducted under standard climatic conditions over a period of 24 h using sandy soils with different pH values. The results of the first experiments showed that most of the radioactivity applied remained in the soils as unchanged fenpropimorph four days after application. In the experiments with the sandy loam and loamy clay, less than 5% of the applied radioactivity was removed by volatilization whereas 11·4% volatilized from the surface of the loamy sand. The comparatively higher volatilization of the fungicide from the loamy sand was confirmed by the later experiments indicating that higher soil pH favoured volatilization of [¹⁴C]fenpropimorph from sandy soils. Thus 5·6% (pH 5·0), 18·9% (pH 5·8) and 28·3% (pH 6·6) of the radioactivity applied volatilized within one day after application. The overall recoveries were between 93·8% and 111·3% in these experiments. © 1998 SCI