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31.
In forest reindeer of northern Sweden outbreaks of keratitis regularly appear in the height of summer in connection with marking of the calves.In forest reindeer conjunctival and corneal lesions, primarily due to foreign bodies and trauma, are found in abundance. In addition, large amounts of different bacteria are present in the conjunctival sacs of clinically healthy as well as diseased animals. It is suggested that the abundance of bacteria and the conjunctival and corneal lesions primarily are a result of the herding conditions of the forest reindeer, and furthermore that they cooperate as etiological factors in the development of keratitis. 相似文献
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For most of history, few things have mattered more to human communities than their relations with soil, because soil provided most of their food and nutrients. Accordingly, some of the earliest written documents were agricultural manuals intended to organize, preserve, and impart soil knowledge. Indeed, ancient civilizations often worshipped the soil as the foundry of life itself. For the past century or two, nothing has mattered more for soils than their relations with human communities, because human action inadvertently ratcheted up rates of soil erosion and, both intentionally and unintentionally, rerouted nutrient flows. 相似文献
34.
Verena Riedinger Marion Renner Maj Rundlöf Ingolf Steffan-Dewenter Andrea Holzschuh 《Landscape Ecology》2014,29(3):425-435
Previous studies focused mainly on the provision of ecosystem services by species movements between semi-natural and managed habitats, whereas data on spillover effects between two managed habitats or between habitats that provide target resources in non-overlapping time periods are lacking. We studied densities of three pollinator groups on sunflower fields as a late mass-flowering crop in 16 landscapes that differed in the relative cover of oil-seed rape as an early mass-flowering crop, in the relative cover of sunflowers and in the relative cover of semi-natural habitats. Our aim was to evaluate dynamics between two crops with non-overlapping flowering periods. Densities of bumble bees in late-flowering sunflower fields were enhanced by early-flowering oil-seed rape. Highest bumble bee densities in the late-flowering crop were reached in landscapes that combined high relative covers of oil-seed rape and semi-natural habitats. Further, low relative covers of oil-seed rape in spring led to decreased bumble bee densities in late-flowering sunflower fields in landscapes with high relative covers of sunflower fields (dilution effect), whereas in landscapes with high relative covers of oil-seed rape, no dilution of bumble bees was found. Thus, our results indicate that early mass-flowering crops can mitigate pollinator dilution in crops flowering later in the season. We conclude that the management of landscape-scale patterns of early and late mass-flowering crops together with semi-natural habitats could be used to ensure crop pollination services. Similar processes could also apply for other species groups and may be an important, but so far disregarded, determinant of population densities in agroecosystems. 相似文献
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ObjectiveTo evaluate the feasibility of measuring pulmonary transit time (PTT) in healthy cats by transthoracic echocardiography using the ultrasound contrast agent Sonovue®. To determine normalized PTT (nPTT) values in 42 healthy cats and to estimate the interobserver variability and the within-day repeatability of nPTT measurements.AnimalsForty-two privately owned healthy cats of different breeds, gender and age presented for cardiac examination.MethodsA bolus injection of contrast agent (Sonovue®) was administered intravenously. The right parasternal short axis echocardiographic view was used to record the contrast agent's transit time from the pulmonary artery to the left atrium. Pulmonary transit time and nPTT were determined independently by three examiners with different levels of experience.ResultsNormalized PTT was 4.12 ± 1.0 (mean ± SD) in our population. The median interobserver variability across our population was 6.8%, the median within-day variability for the three observers were 13.1%, 12.7% and 13%. No effect of the observer's experience on nPTT measurement was identified. Age, sex and body weight did not significantly influence nPTT.ConclusionsThis study demonstrates that nPTT measurement is feasible in cats using ultrasound and the blood pool contrast media Sonovue®. Measurements of nPTT can be performed in a clinical setting. Normalized PTT values in healthy cats are comparable with those reported in healthy dogs. 相似文献
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Background – Cutaneous T‐cell lymphoma (CTCL) in dogs is a heterogeneous disease complex, which consists of nonepitheliotropic (NE) and epitheliotropic forms. These lymphomas are readily recognized by the presence of dominant populations of cytologically atypical lymphocytes. Objective – The objective of this study was to introduce the key features of inflamed NE‐CTCL, which is easily confused with reactive, inflammatory histiocytic disease. Animals – Twenty‐four dogs (mean age 7.5 years) presented with inflamed NE‐CTCL. Lesions presented as nodules, plaques or masses. An initial diagnosis of cutaneous reactive histiocytosis (11 dogs) or histiocytic neoplasia (three dogs) was made by primary pathologists. Methods – Lesions were assessed by histology and immunohistochemistry to detect canine leukocyte antigens. Lesional genomic DNA was extracted and gene rearrangement analysis of the T‐cell receptor γ locus was assessed. Results – The cutaneous lesions consisted of pleocellular infiltration of the dermis with variable extension into the subcutis. The lesions often surrounded vessels and adnexae. Epitheliotropism was minimal or lacking. Small lymphocytes, plasma cells and intermediate to large, cytologically atypical lymphocytes were scattered between prominent histiocytic infiltrates. Atypical lymphocytes often had marked variation in the intensity of CD3 expression. Molecular clonality analysis of the T‐cell receptor γ locus revealed clonal expansion of T cells in 22 of 23 dogs tested. Conclusion – The recognition of inflamed NE‐CTCL and its differentiation from cutaneous reactive histiocytosis depends on careful assessment of lymphocyte morphology and immunostaining patterns. Confirmation of the diagnosis is best accomplished by T‐cell antigen receptor gene rearrangement analysis. 相似文献
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Holland JL Outerbridge CA Affolter VK Maggs DJ 《Journal of the American Veterinary Medical Association》2006,229(9):1442-1446
OBJECTIVE: To compare detection rates of feline herpesvirus 1 (FHV-1) DNA in skin biopsy specimens from cats with herpetic dermatitis, cats with nonherpetic dermatitis, and cats without dermatitis. DESIGN: Prevalence survey. Animals-5 cats (9 biopsy specimens) with herpetic ulcerative dermatitis, 14 cats (17 biopsy specimens) with nonherpetic ulcerative dermatitis, and 8 cats (21 biopsy specimens) without clinically apparent skin lesions. PROCEDURES: A single-phase PCR assay was used to detect FHV-1 DNA in biopsy specimens. Assay results were compared with results of histologic examination. RESULTS: FHV-1 DNA was detected in all 9 biopsy specimens from the 5 cats with herpetic dermatitis and in 1 of 17 biopsy specimens from the 14 cats with nonherpetic dermatitis, but was not detected in any of the 21 biopsy specimens from the 8 cats without dermatitis. When results of histologic examination were used as the gold standard, sensitivity and specificity of the PCR assay were 100% and 95%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results confirmed that FHV-1 DNA can be detected in the skin of cats with herpetic dermatitis and suggest that the virus may play a causative role in the disease. In addition, the PCR assay may be useful in confirming a diagnosis of herpetic dermatitis. 相似文献
40.
Christina-Luise Ross Verena Wilken Stefanie Krück Kerstin Nielsen Karen Sensel-Gunke Frank Ellmer 《Archives of Agronomy and Soil Science》2017,63(14):1939-1950
Fermentation in combination with subsequent composting of biowaste is a preferred method for municipalities to recycle organic byproducts and transform them into useful end products for soil amelioration or plant fertilization. These compost products, especially if obtained from household wastes, can be a source of hazardous components, e.g. heavy metals, pathogens, synthetic chemicals or toxic organic compounds. An avoidance test with two earthworm species (Eisenia fetida and Aporrectodea caliginosa) was conducted to assess the impact of differently processed biowaste based digestate products on soil invertebrates. Body weight changes were recorded, as well as differences in effects on adult versus juvenile earthworms.
While E. fetida showed no avoidance towards the digestate products (negative avoidance, meaning that the tested products were preferred, of 80 to 100 %), A. caliginosa rejected the crude biowaste digestate compost in higher concentrations (avoidance of 45 %), but not the agglomerated or pelletized variants. A clear weight gain of up to 25 % was observed only for individuals of E. fetida. The developmental stages of the worms were not crucial for the outcome of the avoidance test.
Based on the results of this study the application of biowaste products on arable land cannot be recommended without constraints. 相似文献