83 research outputs found

    How are they really doing? Animal welfare on organic laying hen farms in terms of health and behaviour

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    The present study describes the current welfare situation on commercial organic laying hen farms in Sweden in terms of indoor environment, bird health and behaviour.Organic laying hen farms (n = 11) in Sweden were visited for one day each. The farm visits were performed at the end of lay and involved farmer interviews, indoor environment assessments, behavioural observations and tests and clinical examinations in one flock per farm.In 95% of all human avoidance distance test trials performed, the hens distanced themselves from the observer before the test was completed. Median number of birds per flock approaching during a novel object test (n = 4 trials per flock) was 2 (0-9). These results may indicate a high level of fear of humans and general fearfulness among the hens.Plumage damage was especially prevalent and most severe on the breast and belly, tail and wings, with median prevalence of moderate-severe damage of 96% (84-100), 96% (72-100) and 98% (94-100), respectively. Median prevalence of keel bone deviations was 67% (32-84) with 3% fractures (0-8). Median prevalence of breast skin lesions was 57% (10-74). There was a significant positive association between breast skin lesions and keel bone deviations (P = 0.02) and foot pad hyperkeratosis (P < 0.001). Median prevalence of severe hyperkeratosis was 33% (8-96), with prevalence being significantly lower where litter depth was thicker (P = 0.003). More dust bathing events were observed in flocks where litter depth was thicker (P = 0.007).The present study contributes with updated knowledge of laying hen welfare on organic farms in Sweden. The results confirm the findings of previous on-farm studies, demonstrating that important issues, including keel bone damage and severe feather pecking, remain in need of attention to ensure the welfare of laying hens in future commercial egg production

    Easier said than done! Organic farmers consider free-ranging important for laying hen welfare but outdoor areas need more shelter - important gaps between research and practice

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    1. The aim of the present study was to investigate the design and management of free-range areas and their use by birds on commercial organic laying hen farms in Sweden and to document farmers' perspectives on outdoor access for poultry.2. Eleven Swedish organic laying hen farms were visited. The farmers were interviewed about general farm management, bird health and behaviour and outdoor access. The free-range areas were assessed in terms of proportion covered by protective (high) vegetation and any artificial shelters provided. The numbers of hens ranging at different distances from the house were recorded twice during the day.3. The outdoor area within 250m from the house contained 0-5% vegetation cover on six of the farms and at least 80% pasture on seven farms. On 10 farms, no more than 13% of the flock was observed outdoors. Of the hens observed in the free-range area, the median proportion ranging within 20m from the house or veranda per observation event was 99% (IQR=55-100%), confirming reports by the farmers.4. Free-range access was considered important by all farmers, primarily for welfare reasons and most agreed that protective vegetation cover and/or artificial shelters were important in encouraging free-ranging. However, there was marked variation among the farmers in their suggestions on how to attract hens outside

    Does the scientific knowledge reflect the chemical diversity of environmental pollution? – A twenty-year perspective

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    Environmental policymaking relies heavily on the knowledge of the toxicological properties of chemical pollutants. The ecotoxicological research community is an important contributor to this knowledge, which together with data from standardized tests supports policy-makers in taking the decisions required to reach an appropriate level of protection of the environment. The chemosphere is, however, massive and contains thousands of chemicals that can constitute a risk if present in the environment at sufficiently high concentrations. The scientific ecotoxicological knowledge is growing but it is not clear to what extent the research community manages to cover the large chemical diversity of environmental pollution. In this study, we aimed to provide an overview of the scientific knowledge generated within the field of ecotoxicology during the last twenty years. By using text mining of over 130,000 scientific papers we established time-trends describing the yearly publication frequency of over 3500 chemicals. Our results show that ecotoxicological research is highly focused and that as few as 65 chemicals corresponded to half of all occurrences in the scientific literature. We, furthermore, demonstrate that the last decades have seen substantial changes in research direction, where the interest in pharmaceuticals has grown while the interest in biocides has declined. Several individual chemicals showed an especially rapid increase (e.g. ciprofloxacin, diclofenac) or decrease (e.g. lindane and atrazine) in occurrence in the literature. We also show that university- and corporate-based research exhibit distinct publication patterns and that for some chemicals the scientific knowledge is dominated by publications associated with the industry. This study paints a unique picture and provides quantitative estimates of the scientific knowledge of environmental chemical pollution generated during the last two decades. We conclude that there is a large number of chemicals with little, or no, scientific knowledge and that a continued expansion of the field of ecotoxicology will be necessary to catch up with the constantly increasing diversity of chemicals used within the society

    Assessing variation in the potential susceptibility of fish to pharmaceuticals, considering evolutionary differences in their physiology and ecology

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    Fish represent the planet's most diverse group of vertebrates and they can be exposed to a wide range of pharmaceuticals. For practical reasons, extrapolation of pharmaceutical effects from 'model' species to other fish species is adopted in risk assessment. Here, we critically assess this approach. First, we show that between 65% and 86% of human drug targets are evolutionarily conserved in 12 diverse fish species. Focusing on nuclear steroid hormone receptors, we further show that the sequence of the ligand binding domain that plays a key role in drug potency is highly conserved, but there is variation between species. This variation for the oestrogen receptor, however, does not obviously account for observed differences in receptor activation. Taking the synthetic oestrogen ethinyloestradiol as a test case, and using life-table-response experiments, we demonstrate significant reductions in population growth in fathead minnow and medaka, but not zebrafish, for environmentally relevant exposures. This finding contrasts with zebrafish being ranked as more ecologically susceptible, according to two independent life-history analyses. We conclude that while most drug targets are conserved in fish, evolutionary divergence in drug-target activation, physiology, behaviour and ecological life history make it difficult to predict population-level effects. This justifies the conventional use of at least a 10× assessment factor in pharmaceutical risk assessment, to account for differences in species susceptibility.Swedish Foundation for Strategic Environmental Research (Mistra)UK Natural Environment Research Council (NERC)AstraZeneca's Global SHE Research Programm

    Sensitive and robust gene expression changes in fish exposed to estrogen – a microarray approach

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    <p>Abstract</p> <p>Background</p> <p>Vitellogenin is a well established biomarker for estrogenic exposure in fish. However, effects on gonadal differentiation at concentrations of estrogen not sufficient to give rise to a measurable vitellogenin response suggest that more sensitive biomarkers would be useful. Induction of zona pellucida genes may be more sensitive but their specificities are not as clear. The objective of this study was to find additional sensitive and robust candidate biomarkers of estrogenic exposure.</p> <p>Results</p> <p>Hepatic mRNA expression profiles were characterized in juvenile rainbow trout exposed to a measured concentration of 0.87 and 10 ng ethinylestradiol/L using a salmonid cDNA microarray. The higher concentration was used to guide the subsequent identification of generally more subtle responses at the low concentration not sufficient to induce vitellogenin. A meta-analysis was performed with data from the present study and three similar microarray studies using different fish species and platforms. Within the generated list of presumably robust responses, several well-known estrogen-regulated genes were identified. Two genes, confirmed by quantitative RT-PCR (qPCR), fulfilled both the criteria of high sensitivity and robustness; the induction of the genes encoding zona pellucida protein 3 and a nucleoside diphosphate kinase (nm23).</p> <p>Conclusion</p> <p>The cross-species, cross-platform meta-analysis correctly identified several robust responses. This adds confidence to our approach used for identifying candidate biomarkers. Specifically, we propose that analyses of an nm23 gene together with zona pellucida genes may increase the possibilities to detect an exposure to low levels of estrogenic compounds in fish.</p

    Bird health, housing and management routines in Swedish organic broiler chicken farms.

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    Slower-growing broilers on organic farms have replaced fast-growing hybrids to increase bird welfare. Due to limited knowledge of broiler welfare and management on organic farms in Sweden, the study aim was to gather information regarding health, housing and management routines, in order to describe the current situation on these. Farm visits performed in 2018 included 8 out of 12 established organic farms, on which either Rowan Ranger or HubbardJA57/HubbardJA87 were reared. Chickens in the observed flocks were 55 ± 6 (44–62) days of age. Observations included farmer interviews, indoor environment assessments, clinical examinations and gait scoring. Clinical examinations revealed no severe remarks, however minor to moderate plumage dirtiness, food pad dermatitis and hock burns were found in 47%, 21% and 13% of the birds, respectively. Although no severe walking impairments were observed, minor to moderate gait abnormalities were seen in two-thirds of the birds. Gait in birds assessed outdoors was significantly better than in birds observed indoors. Body weight uniformity was low in all flocks. This study provides increased knowledge of certain chicken health and welfare aspects, housing and management on Swedish organic farms. Future research should further investigate important aspects related to bird welfare, such as the high mortality rates observed

    ECOdrug: A database connecting drugs and conservation of their targets across species

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    Pharmaceuticals are designed to interact with specific molecular targets in humans and these targets generally have orthologs in other species. This provides opportunities for the drug discovery community to use alternative model species for drug development. It also means, however, there is potential for mode of action related effects in non-target wildlife species as many pharmaceuticals reach the environment through patient use and manufacturing wastes. Acquiring insight in drug target ortholog predictions across species and taxonomic groups has proven difficult because of the lack of an optimal strategy and because necessary information is spread across multiple and diverse sources and platforms. We introduce a new research platform tool, ECOdrug, that reliably connects drugs to their protein targets across divergent species. It harmonizes ortholog predictions from multiple sources via a simple user interface underpinning critical applications for a wide range of studies in pharmacology, ecotoxicology and comparative evolutionary biology. ECOdrug can be used to identify species with drug targets and identify drugs that interact with those targets. As such, it can be applied to support intelligent targeted drug safety testing by ensuring appropriate and relevant species are selected in ecological risk assessments. ECOdrug is freely accessible and available at: Http://www.ecodrug.org

    Genetic variations in A20 DUB domain provide a genetic link to citrullination and neutrophil extracellular traps in systemic lupus erythematosus

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    Objectives: Genetic variations in TNFAIP3 (A20) de-ubiquitinase (DUB) domain increase the risk of systemic lupus erythematosus (SLE) and rheumatoid arthritis. A20 is a negative regulator of NF-κB but the role of its DUB domain and related genetic variants remain unclear. We aimed to study the functional effects of A20 DUB-domain alterations in immune cells and understand its link to SLE pathogenesis. Methods: CRISPR/Cas9 was used to generate human U937 monocytes with A20 DUB-inactivating C103A knock-in (KI) mutation. Whole genome RNA-sequencing was used to identify differentially expressed genes between WT and C103A KI cells. Functional studies were performed in A20 C103A U937 cells and in immune cells from A20 C103A mice and genotyped healthy individuals with A20 DUB polymorphism rs2230926. Neutrophil extracellular trap (NET) formation was addressed ex vivo in neutrophils from A20 C103A mice and SLE-patients with rs2230926. Results: Genetic disruption of A20 DUB domain in human and murine myeloid cells did not give rise to enhanced NF-κB signalling. Instead, cells with C103A mutation or rs2230926 polymorphism presented an upregulated expression of PADI4, an enzyme regulating protein citrullination and NET formation, two key mechanisms in autoimmune pathology. A20 C103A cells exhibited enhanced protein citrullination and extracellular trap formation, which could be suppressed by selective PAD4 inhibition. Moreover, SLE-patients with rs2230926 showed increased NETs and increased frequency of autoantibodies to citrullinated epitopes. Conclusions: We propose that genetic alterations disrupting the A20 DUB domain mediate increased susceptibility to SLE through the upregulation of PADI4 with resultant protein citrullination and extracellular trap formation

    A Complex Genomic Rearrangement Involving the Endothelin 3 Locus Causes Dermal Hyperpigmentation in the Chicken

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    Dermal hyperpigmentation or Fibromelanosis (FM) is one of the few examples of skin pigmentation phenotypes in the chicken, where most other pigmentation variants influence feather color and patterning. The Silkie chicken is the most widespread and well-studied breed displaying this phenotype. The presence of the dominant FM allele results in extensive pigmentation of the dermal layer of skin and the majority of internal connective tissue. Here we identify the causal mutation of FM as an inverted duplication and junction of two genomic regions separated by more than 400 kb in wild-type individuals. One of these duplicated regions contains endothelin 3 (EDN3), a gene with a known role in promoting melanoblast proliferation. We show that EDN3 expression is increased in the developing Silkie embryo during the time in which melanoblasts are migrating, and elevated levels of expression are maintained in the adult skin tissue. We have examined four different chicken breeds from both Asia and Europe displaying dermal hyperpigmentation and conclude that the same structural variant underlies this phenotype in all chicken breeds. This complex genomic rearrangement causing a specific monogenic trait in the chicken illustrates how novel mutations with major phenotypic effects have been reused during breed formation in domestic animals
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