Efficient age determination: how freezing affects eye lens weight of the small rodent species Arvicola terrestris

Age determination of animals by measuring the weight of their eye lenses is a widely used method in wildlife biology. In general, it is recommended to prepare lenses immediately after trapping to avoid errors in the age estimation due to decomposition of lens tissue. However, in many field studies, large numbers of animals need to be trapped over long periods of time in huge areas and by many different field workers. Therefore, the immediate preparation of eye lenses imposes a considerable logistic constraint that could be avoided by prior freezing of trapped animals. To assess the impact of freezing, weights of lens of frozen and unfrozen eyes of 114 Arvicola terrestris were compared pair wise. The frozen lenses weighed at average 3.3% (95% CI: 2.4-4.1%) more than the unfrozen ones from the same animals. Freezing time, weight of lenses and mean temperature of the trapping day as an indicator of decomposition speed did not affect the freezing-induced weight increase. Age estimates based on weights of unfrozen lenses varied between 24 and 445days. Estimates based on frozen lenses were systematically higher. Applying a constant correction factor of 1.033−1 for the weight of frozen lenses corrects this overestimation of age. We conclude that age determination with frozen lenses of small rodents can yield valid age estimates if a correction factor for freezing is applied. Thus, age determination can be organised much more efficiently in field studies, which is highly advantageous for many ecological, agricultural and epidemiological research project

Direktsaat von Mais im Biolandbau

Der Mais ist für die Fütterung von Wieder- als auch Nichtwiederkäuer eine sehr wertvolle Pflanze. Im Biolandbau wird für den Maisanbau aufgrund der einfacheren Unkrautregulierung standardmässig der Pflug verwendet. Bezüglich Bodenerosion, Verdichtung und Abschwemmung ist aber gerade beim Maisanbau der Pflugeinsatz nicht optimal. Die Direktsaat von Mais löst diese Probleme weitgehend und erhöht auch im Biolandbau die Akzeptanz, da auf dem geschlossenen Boden auch die Ernte bodenschonender durchgeführt werden kann. Ein Direktsaatsystem ohne Einsatz von Roundup ist äusserst anspruchsvoll. Die letztjährigen Versuche haben gezeigt, dass unter optimalen Voraussetzungen die Direktsaat von Mais im Biolandbau möglich ist. Die Wahl der Gründüngung ist für die Unkrautkonkurrenz und damit für die Wirtschaftlichkeit entscheidend. Die Messerwalze hilft die Gründüngungen soweit zu schädigen, dass sie den Mais nicht mehr konkurrenzieren. Auf dieses Gerät kann nicht verzichtet werden. Die Direktsaat in eine stehende Begrünung ist aber sehr anspruchsvoll. Für dieses Jahr wurden die vier verschiedenen Begrünungsmischungen auf drei Standorten im Kanton Aargau, Zürich und Schaffhausen im Herbst 2013 ausgesät. Im Frühjahr 2014 erfolgte die Direktsaat

Age, season and spatio-temporal factors affecting the prevalence of Echinococcus multilocularis and Taenia taeniaeformis in Arvicola terrestris

Background: Taenia taeniaeformis and the related zoonotic cestode Echinococcus multilocularis both infect the water vole Arvicola terrestris. We investigated the effect of age, spatio-temporal and season-related factors on the prevalence of these parasites in their shared intermediate host. The absolute age of the voles was calculated based on their eye lens weights, and we included the mean day temperature and mean precipitation experienced by each individual as independent factors. Results: Overall prevalences of E. multilocularis and T. taeniaeformis were 15.1% and 23.4%, respectively, in 856 A. terrestris trapped in the canton Zürich, Switzerland. Prevalences were lower in young (≤ 3 months: E. multilocularis 7.6%, T. taeniaeformis 17.9%) than in older animals (>7 months: 32.6% and 34.8%). Only 12 of 129 E. multilocularis-infected voles harboured protoscoleces. Similar proportions of animals with several strobilocerci were found in T. taeniaeformis infected voles of <5 months and ≥5 months of age (12.8% and 11.9%). Multivariate analyses revealed strong spatio-temporal variations in prevalences of E. multilocularis. In one trapping area, prevalences varied on an exceptional high level of 40.6-78.5% during the whole study period. Low temperatures significantly correlated with the infection rate whereas precipitation was of lower importance. Significant spatial variations in prevalences were also identified for Taenia taeniaeformis. Although the trapping period and the meteorological factors temperature and precipitation were included in the best models for explaining the infection risk, their effects were not significant for this parasite. Conclusions: Our results demonstrate that, besides temporal and spatial factors, low temperatures contribute to the risk of infection with E. multilocularis. This suggests that the enhanced survival of E. multilocularis eggs under cold weather conditions determines the level of infection pressure on the intermediate hosts and possibly also the infection risk for human alveolar echincoccosis (AE). Therefore, interventions against the zoonotic cestode E. multilocularis by deworming foxes may be most efficient if conducted just before and during winter

Modelling the habitat selection of the bearded vulture to predict areas of potential conflict with wind energy development in the Swiss Alps

Global warming impels countries to dramatically reduce their release of greenhouse gas emissions and increase their reliance on green energy, notably wind power. Yet, without cautious planning, the sprawl of wind turbines could negatively impact biodiversity, especially flying vertebrates that are otherwise already threatened. Inherent risks for vulnerable and endangered species are usually mitigated by banning constructions within buffer areas around nesting locations. This approach, however, neglects species’ range dynamics and particularly falls short of protecting expanding populations, as in the case of natural returns or reintroduction programmes. We present here an alternative approach to mitigate wildlife-infrastructure conflicts, applying it to the bearded vulture, a species reintroduced in the European Alps. Combining casual observations and GPS locations of tagged individuals, we built several predictive distribution models with respect to bearded vulture age class and season and tested for models’ ability to correctly predict its future expansion in the Alps. Although immature and adult birds showed different habitat selection patterns, both in summer and winter, wide areas of the Swiss Alps (40%) offer suitable habitat. The above combined information enabled correctly predicting today’s use by breeding bearded vultures of previously unused areas. This study not only provides a detailed analysis of the bearded vulture’s ecological requirements in the Alps but also helps delineating areas where conflicts with wind energy production and other aerial infrastructure will likely occur in Switzerland. The resulting maps provide a large-scale planning tool that companies, landscape planners and wildlife managers can use in any environmental risk assessments

Successful cultivation of grain legumes mixed with cereals

This leaflet describes the suitability of the most promising grain legume/cereal mixtures that were tested in field trials, and provides in-depth information on the cultivation, economic efficiency and use of proven mixtures in Switzerland

Colorful Collar-Covers and Bells Reduce Wildlife Predation by Domestic Cats in a Continental European Setting

In many areas, domestic cats are the most abundant predators of small vertebrates. Due to the potential impact on prey populations by cats, there are calls to investigate the effectiveness of visual and acoustic cues as measures to reduce the cat’s hunting efficiency. In this study, we complement previous studies on the efficacy of Birdsbesafe collar-covers (BBScc) in a so far not investigated Continental European setting and explore the effectiveness in combination with a bell. We also evaluate the tolerability of these devices by the cat and the acceptance by their owners. With a randomized and comparative citizen science-based approach we collected data from 26 households with 31 study cats, which were wearing either a BBScc or both a BBScc and a bell. The BBScc reduced the number of birds brought home by 37% (probability of reduction of 88%). The number of mammals brought home was reduced by 54–62%, but only with the additional bell (probability of reduction of &gt;99%). About one fourth of the birds that could be dissected were found to have collided with a hard object prior to having been brought home by the cats. Our results are in line with previous findings from Australia, the United States, and the United Kingdom and highlight the great potential of visual and acoustic cues in reducing hunting success in domestic cats also in Continental Europe. On the other hand, our result show that the number of prey brought home by cats overestimates their hunting bag, if scavenging is not considered. The majority of cat owners reported that their cats habituated quickly to the BBScc. However, frequent scratching in some cats indicates that some individuals may not habituate. Most participating cat owners had a positive attitude toward the BBScc and said that they were willing to use it after the study. However, cat owners reported that their social environment (e.g., neighbors, family, friends) was relatively skeptical, which indicates a need for communication. To conclude, commercially available devices with visual and acoustic stimuli are straightforward and effective ways to mitigate the potentially harmful effect of domestic cats on wildlife

Influence of urbanization on the epidemiology of intestinal helminths of the red fox ( Vulpes vulpes ) in Geneva, Switzerland

Dixenous helminths that depend on rodent intermediate hosts are supposed to be negatively affected by urbanization due to lower supply of rodents in urbanized environments. Prevalence rates of dixenous, non-strictly monoxenous, and monoxenous helminths in 228 red foxes (Vulpes vulpes) along a gradient of increasing urbanization were assessed by morphological parasite identification in the city of Geneva, Switzerland. Multivariate analyses for the five most prevalent helminth species or genera revealed a significant decrease of prevalence rates for the dixenous helminths Echinococcus multilocularis and Taenia spp. from the rural (52.1 and 54.3%, respectively) to the urban area (30.0 and 20.0%, respectively), but not for the monoxenous nematode Uncinaria stenocephala (overall prevalence of 78.2%) and the non-strictly monoxenous nematode Toxocara canis (overall prevalence of 44.3%). The lower prevalence of Toxascaris leonina in the urban area (8.0%) compared to the rural area (59.6%) raises the question of whether rodent paratenic hosts play a major role for the population dynamics of this specie

Innovation in Argentina's Poultry Nutrition and Health Industry: Strategies of Knowledge-intensive Business Services

El objetivo de este estudio fue analizar las empresas de nutrición y sanidad aviar entre los años 2015-2018 y cómo innovaron para sostenerse en contextos globalizados. Se consideró como supuesto principal que las diferencias estaban dadas por el tipo de innovaciones desarrolladas y sus relaciones con otras firmas e instituciones. Para el trabajo fueron estudiadas -desde un enfoque sistémico sobre la innovación y en base a una encuesta- 40 empresas de capitales nacionales y multinacionales en la Argentina. Se concluyó que las empresas efectuaron diferentes tipos de innovaciones y que éstas son características diferenciadoras significativas: la innovación en servicios intensivos en conocimiento, el tipo de exportación y la cooperación tecnológica con universidades.The aim of the study was to analyze the innovation strategy of Argentine poultry nutrition and health firms between 2015-2018 to sustain themselves in globalized contexts. The main assumption was that the differences were given by the type of innovations and their relationships with other firms and institutions. By means of a survey, 40 firms in Argentina, of national and multinational origin, were studied from a systemic innovation approach. The conclusion was that the firms carried out different types of innovations, with significant differentiating characteristics, such as: the innovation in knowledge-intensive services, the type of export and the technological cooperation with universities.Facultad de Humanidades y Ciencias de la Educació

El Sector software y servicios informáticos en Entre Ríos: Caracterización y desafíos para su desarrollo

The article aims to describe and analyze the firms of the software services industry located in the province of Entre Ríos (Argentina), and compare them with those IN the rest of the country. For this, the contributions of the specialized literature on Knowledge Intensive Business Service (KIBS) are used as a framework, which allows to defne general and specifc characteristics of these firms. For the analysis, data from a survey carried out at the national level in 2017 were used in provinces where the largest agglomerations of SSI FIRMS are registered (out of the 177 frms in the sample, 32 correspond to Entre Ríos).Based on the results, a series of reflections on the potential of this sector are outlined considering it as clusters of Information Technology and Communication at the local level in the province of Entre Ríos. Theconclusions raise research problems and policy instruments for the sector at a regional level.El artículo tiene como objetivo describir y analizar las firmas del sector de software y servicios informáticos localizadas en la provincia de Entre Ríos (Argentina) y compararlas con las del resto del país. Para esto se utiliza como marco de referencia los aportes de la literatura especializada sobre Knowledge Intensive Business Service (KIBS), que permite defnir características generales y específcas de este tipo de firmas.Para el análisis se utilizaron datos de un relevamiento efectuado a nivel nacional en el año 2017 en provincias donde se registran las mayores aglomeraciones de firmas SSI (de las 177 firmas de la muestra, corresponden 32 a Entre Ríos).En base a los resultados se plantean una serie de reflexiones acerca de las potencialidades de este sector en términos de clusters de Tecnologías de la Información y Comunicación a escala local en la provincia de Entre Ríos. En las conclusiones se plantean problemas de investigación e instrumentos de políticas para el sector

Stability of the southern European border of Echinococcus multilocularis in the Alps: evidence that Microtus arvalis is a limiting factor

The known range of the zoonotic fox tapeworm Echinococcus multilocularis has expanded since the 1990s, and today this parasite is recorded in higher abundances throughout large parts of Europe. This phenomenon is mostly attributed to the increasing European fox populations and their invasion of urban habitats. However, these factors alone are insufficient to explain the heterogeneous distribution of the parasite in Europe. Here, we analysed the spatial interrelationship of E. multilocularis with the known distribution of seven vole species in Ticino, southern Switzerland. Among 404 necropsied foxes (1990-2006) and 79 fox faecal samples (2010-2012), E. multilocularis was consistently found in the north of the investigated area. No expansion of this endemic focus was recorded during the 22 years of the study period. This stable endemic focus is coincident with the known distribution of the vole species Microtus arvalis but not, or only partly, with the distribution of the other autochthonous vole species. Our results give evidence that this vole species plays a crucial role in the maintenance of the parasite's life cycle and that its absence could be a limiting factor for the spread of E. multilocularis in this regio