Risk factors for infection of sow herds with porcine reproductive and respiratory syndrome (PRRS) virus

In 1992, the porcine reproductive and respiratory syndrome virus (PRRSV) of European type (PRRSV-EU) was introduced in Denmark. By 1996, the virus had spread to approximately 25% of the Danish herds. In January 1996, a modified-live vaccine based on the American type of the virus (PRRSV-US) was used in replacement boars for Danish artificial insemination (AI) centres and from July 1996, the vaccine was used in PRRSV-EU infected herds for prevention of disease. Soon after vaccine introduction, PRRSV non-infected herds experienced outbreaks of disease due to infection with PRRSV-US. In this study, we investigated the risk factors (biosecurity level, animals, exposure from PRRSV-US-infected neighbour herds, semen, herd size, pig density and herd density) for infection with PRRSV-US in a cohort of 1071 sow herds; we used a nested case-control study. The retrospective observation period lasted from June 1996 (when they all were non-infected) to October 1997. Seventy-three non-vaccinated, closed sow herds became infected with the vaccine strain during this period. Each case herd was matched with two control herds from the cohort (controls had not been infected at the time of infection in the case herds). The data were analysed using a Cox-regression model. The hazard of infection increased significantly with exposure from PRRSV-US-infected neighbouring herds, purchase of animals from herds incubating PRRSV-US infection, increasing herd size and purchase of semen from boars at PRRSV-US-infected AI centres. The results are consistent with the modified-live vaccine strain spread to other herds by trade with animals and semen and by neighbour (area) transmission. We suggest that virus spread by aerosols was a frequent mode of transmission.     

Dermatitis associated with microfilariae (Filarioidea) in 10 dogs

Dermatitis associated with microfilariae of a nematode of the superfamily Filarioidea was diagnosed in 10 dogs from the western United States. Clinically, lesions were single or multiple papules and plaques with alopecia, scarring, erythema, ulceration, or crusting. Eight dogs had lesional pruritus. Microscopically, there was perivascular, periglandular, to interstitial inflammation, with many eosinophils and/or plasma cells, and scarring affecting the dermis and subcutis. Microgranulomas containing microfilaria were seen in six dogs. Microfilariae were noted in microgranulomas or free in the dermis or subcutis, but not in vessels. In one case, an adult female nematode emerged from a biopsy sample that was placed in physiologic saline. Study of this nematode revealed that it was a filarioid of the family Onchocercidae; it was identified as Acanthocheilonema sp. (syn: Dipetalonema ). Antigen tests of five dogs were negative for Dirofilaria immitis . The Knott tests and/or filter tests of nine dogs were negative for microfilariae. An indirect fluorescence antibody test of one dog was also negative for D. immitis . One dog was not evaluated for microfilariae.     

Suitability of carbon isotope discrimination,ash content and single mineral concentration for the selection of drought‐tolerant winter rye

Carbon isotope discrimination (?) has been proposed as selection criterion for grain yield under dry conditions, and ash content (m_a) and mineral concentration were suggested as surrogates for ?. In this study, the relationship between grain yield, ?, m_a and mineral concentration (Si, Ca, K, Mg) was examined in 2011 and 2012 on 16 winter rye genotypes grown under severe drought, mild drought (2012 only) and well‐watered conditions. Analyses were performed on mature flag leaves and grains. Highly significant differences between water regimes occurred for all measured traits. ?, m_a and mineral concentrations were significantly correlated with grain yield under severe drought in 2011, but not in 2012 except for ? in flag leaf. ? was related to m_a and mineral concentrations. Although the correlations were quite inconsistent, the results indicate that the measured traits can potentially be used as selection criterion for drought tolerance in rye. For a final statement about the suitability of these traits in rye breeding, the results should be secured with a larger and more diverse set of genotypes.     

Atmospheric CO2 enrichment induces life strategy- and species-specific responses of collembolans in the rhizosphere of sugar beet and winter wheat

We studied atmospheric CO₂ enrichment effects on life form types, species composition, dominance structure and individual density of collembolans under cultivation of sugar beet and winter wheat. The study was part of a long-term CO₂ enrichment field experiment (FACE: Free Air CO₂ Enrichment) at the Federal Agricultural Research Centre (FAL) in Braunschweig (Germany), using isotopically labelled CO₂. The stable C-isotopic signature (δ¹³C) of collembolan species, plant material, and soil indicated CO₂ impacts on C translocation. The δ¹³C values of both crops significantly increased from above-ground to below-ground plant parts and significantly decreased under FACE conditions. The δ¹³C values of collembolan species differed significantly depending on CO₂ treatment and crop and showed a distinct tendency depending on plant growth stage. The extent, to which δ¹³C values of collembolans decreased under FACE conditions, was species- and life strategy-dependent. The stable C-isotopic signatures of euedaphic and hemiedaphic species were similar in the control, but, depending on crop, differently affected by atmospheric CO₂ enrichment. Under winter wheat cultivation, hemiedaphic species showed more negative δ¹³C values than euedaphic ones under FACE conditions. CO₂ enrichment effects on occurrence, density and dominance distribution of the collembolan species differed strongly between crops and their developmental stages, which reveal crop-specific below-ground effects due to different food qualities in the rhizosphere. CO₂ impacts were stronger under sugar beet compared to winter wheat cultivation. Independent of crop, CO₂ enrichment enhanced the diversity of collembolans before harvest and increased the proportion of hemiedaphic in relation to euedaphic species in a community. Our results on collembolan communities imply CO₂-induced changes in the root-derived carbon resources used by the soil food web. The present study reveals atmospheric CO₂ enrichment impacts to specifically affect collembolan species according to their food preferences.     

Hearth Bread Characteristics: Effect of Protein Quality,Protein Content,Whole Meal Flour,DATEM, Proving Time,and Their Interactions

The effects of protein quality, protein content, ingredients, and baking process of flour blends on hearth loaves were studied. The flour blends varied in protein composition and content. Flours of strong protein quality produced hearth loaves with larger loaf volume, larger bread slice area, and higher form ratio (height/width) than flours of weak protein quality. The effect of protein content on hearth loaf depended on the size distribution of the proteins. Increasing protein content was associated with increased percentage of the largest glutenin polymers, and loaf volume and slice area increased significantly. The form ratio, however, remained unchanged with increasing flour protein content. Strong protein quality flours tolerated addition of whole meal flour better than weak protein quality flours. Increased amount of flour with strong protein quality improved hearth bread characteristics to a larger extent than increased protein content. Diacetyl tartaric acid ester of monoglycerides (DATEM) improved hearth bread characteristics, but the effect was small compared with the effect of protein composition.     

Effects of Plant Extracts on the Reversal of Glucose-Induced Impairment of Stress-Resistance in Caenorhabditis elegans

Enhanced blood glucose levels are a hallmark of diabetes and are associated with diabetic complications and a reduction of lifespan. In order to search for plant extracts that display preventive activities in such a scenario, we tested 16 extracts used in human nutrition for their survival enhancing activities in the nematode Caenorhabditis elegans. Nematodes were exposed for 48 h to 10 mM glucose in the absence or presence of 0.1 % extract. Thereafter, survival was measured at 37 °C. Extracts made from coffee, kola, rooibos and cinnamon, did not influence the glucose-induced reduction of survival. Those made from ginseng, camomile, lime blossom, paraguay tea, balm, rhodiola, black tea, or knotgrass all extended the lifespan of the glucose-treated nematodes significantly but did not rescue survival completely. Extracts from the leaves of blackberries, from hibiscus, elderberries, or jiaogulan completely countered the glucose-induced survival reduction. A potent activation of the proteasome was shown for the most preventive extracts suggesting a more efficient degradation of proteins impaired by glucose. In conclusion, we present a simple animal model to screen for plant extracts with potency to reverse glucose toxicity. Extracts from blackberry leaves, hibiscus, elderberries, and jiaogulan were identified as very potent in this regard whose exact mechanisms of action appear worthwile to investigate at the molecular level.     

Intranasal peptide-induced peripheral tolerance: the role of IL-10 in regulatory T cell function within the context of experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is a T cell-mediated autoimmune disease commonly employed as a model for multiple sclerosis. Extensive studies have demonstrated that EAE may be prevented or ameliorated by the intranasal administration of soluble peptides representing encephalitogenic epitopes. There is increasing evidence that this peptide administration may function via the generation of regulatory cells. The mechanism of action of these cells remains controversial and it seems likely that it may vary between experimental models. At present the majority of work on regulatory cells has centred on characterising naturally occurring regulators, or those generated artificially ex vivo, and less is known about induced regulatory cells produced following peptide administration. This report aims to briefly outline the evidence for the existence of natural regulatory T cells and to introduce the sub-types of induced regulatory T cells now recognised.In several of these regulatory cell systems investigated to date, interleukin-10 (IL-10) has been shown to be important in cell function. This has not been directly investigated in a model employing peptide therapy to induce peripheral tolerance, hence the purpose of this study was to investigate the role of IL-10 in the generation of these regulatory cells. This work has employed both a TCR transgenic mouse system, for predominantly in vitro studies of cell function, and an IL-10 knock-out mouse strain to investigate in vivo disease protection. The results summarised in this report demonstrate that IL-10 is fundamentally important in the generation of disease protection following intranasal peptide therapy.