Showing papers by "University of Hohenheim published in 2015"

Rising Temperatures Reduce Global Wheat Production

Abstract: Crop models are essential tools for assessing the threat of climate change to local and global food production(1). Present models used to predict wheat grain yield are highly uncertain when simulating how crops respond to temperature(2). Here we systematically tested 30 different wheat crop models of the Agricultural Model Intercomparison and Improvement Project against field experiments in which growing season mean temperatures ranged from 15 degrees C to 32 degrees C, including experiments with artificial heating. Many models simulated yields well, but were less accurate at higher temperatures. The model ensemble median was consistently more accurate in simulating the crop temperature response than any single model, regardless of the input information used. Extrapolating the model ensemble temperature response indicates that warming is already slowing yield gains at a majority of wheat-growing locations. Global wheat production is estimated to fall by 6% for each degrees C of further temperature increase and become more variable over space and time.

On-line application of near infrared (NIR) spectroscopy in food production

Abstract: Near infrared (NIR) spectroscopy represents an emerging analytical technique, which is enjoying increasing popularity in the food processing industry due to its low running costs, and since it does not require sample preparation. Moreover, it is a non-destructive, environmental friendly, rapid technique capable for on-line application. Therefore, this technique is predestined for implementation as an analytical tool in industrial processing. The different fields of application of NIR spectroscopy reported in the present review highlight its enormous versatility. Quantitative analyses of chemical constituents using this methodology are widespread. Moreover, a wide range of qualitative determinations, e.g. for authenticity control, sample discrimination, the assessment of sensory, rheological or technological properties, and physical attributes have been reported. Both animal- and plant-derived foodstuffs have been evaluated in this context. Highly diverse matrices such as intact solid samples, free-flowing solids, pasty, and fluid samples can by analysed by NIR spectroscopy. Sophisticated conditions for the application in industrial scale comprise among others measurements on moving conveyor belts, in continuous flows in tubes, and monitoring of fermentation processes. For such purposes, different construction designs of NIR spectrometers for hyperspectral imaging, portable devices, fibre optical and direct contact probes as well as tube integrated probes measuring through windows, and automated sample cell loading have been developed. In the present review, emphasis was put on studies dealing with on-line application of NIR spectroscopy for industrial processes in the food industry, which were categorised according to their application conditions into semi-industrial scale and industrial scale.

Multimodel ensembles of wheat growth: many models are better than one

Abstract: Crop models of crop growth are increasingly used to quantify the impact of global changes due to climate or crop management. Therefore, accuracy of simulation results is a major concern. Studies with ensembles of crop models can give valuable information about model accuracy and uncertainty, but such studies are difficult to organize and have only recently begun. We report on the largest ensemble study to date, of 27 wheat models tested in four contrasting locations for their accuracy in simulating multiple crop growth and yield variables. The relative error averaged over models was 24-38% for the different end-of-season variables including grain yield (GY) and grain protein concentration (GPC). There was little relation between error of a model for GY or GPC and error for in-season variables. Thus, most models did not arrive at accurate simulations of GY and GPC by accurately simulating preceding growth dynamics. Ensemble simulations, taking either the mean (e-mean) or median (e-median) of simulated values, gave better estimates than any individual model when all variables were considered. Compared to individual models, e-median ranked first in simulating measured GY and third in GPC. The error of e-mean and e-median declined with an increasing number of ensemble members, with little decrease beyond 10 models. We conclude that multimodel ensembles can be used to create new estimators with improved accuracy and consistency in simulating growth dynamics. We argue that these results are applicable to other crop species, and hypothesize that they apply more generally to ecological system models.

The genomes of two key bumblebee species with primitive eusocial organization

Abstract: The shift from solitary to social behavior is one of the major evolutionary transitions Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Endogenous Arabidopsis messenger RNAs transported to distant tissues

Abstract: The concept that proteins and small RNAs can move to and function in distant body parts is well established. However, non-cell-autonomy of small RNA molecules raises the question: To what extent are protein-coding messenger RNAs (mRNAs) exchanged between tissues in plants? Here we report the comprehensive identification of 2,006 genes producing mobile RNAs in Arabidopsis thaliana. The analysis of variant ecotype transcripts that were present in heterografted plants allowed the identification of mRNAs moving between various organs under normal or nutrient-limiting conditions. Most of these mobile transcripts seem to follow the phloem-dependent allocation pathway transporting sugars from photosynthetic tissues to roots via the vasculature. Notably, a high number of transcripts also move in the opposite, root-to-shoot direction and are transported to specific tissues including flowers. Proteomic data on grafted plants indicate the presence of proteins from mobile RNAs, allowing the possibility that they may be translated at their destination site. The mobility of a high number of mRNAs suggests that a postulated tissue-specific gene expression profile might not be predictive for the actual plant body part in which a transcript exerts its function.

Genomic signatures of evolutionary transitions from solitary to group living

Abstract: The evolution of eusociality is one of the major transitions in evolution, but the underlying genomic changes are unknown We compared the genomes of 10 bee species that vary in social complexity, representing multiple independent transitions in social evolution, and report three major findings First, many important genes show evidence of neutral evolution as a consequence of relaxed selection with increasing social complexity Second, there is no single road map to eusociality; independent evolutionary transitions in sociality have independent genetic underpinnings Third, though clearly independent in detail, these transitions do have similar general features, including an increase in constrained protein evolution accompanied by increases in the potential for gene regulation and decreases in diversity and abundance of transposable elements Eusociality may arise through different mechanisms each time, but would likely always involve an increase in the complexity of gene networks

Impacts of Informal Caregiving on Caregiver Employment, Health, and Family

Abstract: As the aging population increases, the demand for informal caregiving is becoming an ever more important concern for researchers and policy-makers alike. To shed light on the implications of informal caregiving, this paper reviews current research on its impact on three areas of caregivers’ lives: employment, health, and family. Because the literature is inherently interdisciplinary, the research designs, sampling procedures, and statistical methods used are heterogeneous. Nevertheless, we are still able to draw several important conclusions: first, despite the prevalence of informal caregiving and its primary association with lower levels of employment, the affected labor force is seemingly small. Second, such caregiving tends to lower the quality of the caregiver’s psychological health, which also has a negative impact on physical health outcomes. Third, the implications for family life remain under investigated. The research findings also differ strongly among subgroups, although they do suggest that female, spousal, and intense caregivers tend to be the most affected by caregiving.

Integrative Analysis of Head and Neck Cancer Identifies Two Biologically Distinct HPV and Three Non-HPV Subtypes

Abstract: Purpose: Current classification of head and neck squamous cell carcinomas (HNSCC) based on anatomic site and stage fails to capture biologic heterogeneity or adequately inform treatment. Experimental Design: Here, we use gene expression-based consensus clustering, copy number profiling, and human papillomavirus (HPV) status on a clinically homogenous cohort of 134 locoregionally advanced HNSCCs with 44% HPV + tumors together with additional cohorts, which in total comprise 938 tumors, to identify HNSCC subtypes and discover several subtype-specific, translationally relevant characteristics. Results: We identified five subtypes of HNSCC, including two biologically distinct HPV subtypes. One HPV + and one HPV − subtype show a prominent immune and mesenchymal phenotype. Prominent tumor infiltration with CD8 + lymphocytes characterizes this inflamed/mesenchymal subtype, independent of HPV status. Compared with other subtypes, the two HPV subtypes show low expression and no copy number events for EGFR/HER ligands. In contrast, the basal subtype is uniquely characterized by a prominent EGFR/HER signaling phenotype, negative HPV-status, as well as strong hypoxic differentiation not seen in other subtypes. Conclusion: Our five-subtype classification provides a comprehensive overview of HPV + as well as HPV − HNSCC biology with significant translational implications for biomarker development and personalized care for patients with HNSCC. Clin Cancer Res; 21(4); 870–81. ©2014 AACR .

The effect of nitrification inhibitors on the nitrous oxide (N2O) release from agricultural soils—a review

Abstract: The use of nitrification inhibitors (NI) is a technique which is able to improve N fertilizer use efficiency, to reduce nitrate leaching and to decrease the emission of the climate‐relevant gas N₂O simultaneously, particularly in moderately fertilized agricultural systems adapted to plant N demand. The ammonia monooxygenase (AMO) is the first enzyme which is involved in the oxidation of NH$ _4^+ $ to NO$ _3^ - $ in soils. The inhibition of the AMO by NIs directly decreases the nitrification rate and it reduces the NO$ _3^- $ concentration which serves as substrate for denitrification. Hence, the two main pathways of N₂O production in soils are blocked or their source strength is at least decreased. Although it has been shown that archaea are also able to oxidize NH₃, results from literature suggest that the enzymatic activity of NH₃oxidizing bacteria is the most important target for NIs because it was much stronger affected. The application of NIs to reduce N₂O emissions is most effective under conditions in which the NI remains close to the N ‐ fertilizer. This is the case when the NI was sprayed on mineral ‐ N fertilizer granules or thoroughly mixed with liquid fertilizers. Most serious problems of spatial separation of NI and substrate emerge on pasture soils, where N₂O hotspots occur under urine and to a lesser extent under manure patches. From the few studies on the effect of different NI quantities it seems that the amount of NI necessary to reduce N₂O emissions is below the recommendations for NI amounts in practice. NIs can improve the fertilizer value of liquid manure. For instance, the addition of NIs to slurry can increase N uptake and yield of crops when NO$ _3^ - $ ‐ N leaching losses are reduced. It has clearly been demonstrated that NIs added to cattle slurry are very effective in reducing N₂O as well as NO emissions after surface application and injection of slurry into grassland soils. In flooded rice systems NIs can reduce CH₄emission significantly, whereas the effect on CO₂emission is varying. On the other hand, as an effect of the delay of nitrification by NIs, NH₃emission might increase when N fertilizers are not incorporated into the soil. As compared to other measures NIs have a high potential to reduce N₂O emissions from agricultural soils. Further, no other measure has so consistently been proofed according its efficiency to reduce N₂O emissions. From the published data [Akiyama et al. (2010) and more recent data from the years 2010–2013; 140 data sets in total] a reduction potential of approx. 35% seems realistic; however, further measurements in different management systems, particularly in regions with intense frost/thaw cycles seem necessary to confirm this reduction potential. These measurements generally should cover a whole annual cycle.

Is the privacy paradox a relic of the past? An in‐depth analysis of privacy attitudes and privacy behaviors

Abstract: The privacy paradox states that online privacy concerns do not sufficiently explain online privacy behaviors on social network sites (SNSs). In this study, it was first asked whether the privacy paradox would still exist when analyzed as in prior research. Second, it was hypothesized that the privacy paradox would disappear when analyzed in a new approach. The new approach featured a multidimensional operationalization of privacy by differentiating between informational, social, and psychological privacy. Next to privacy concerns, also, privacy attitudes and privacy intentions were analyzed. With the aim to improve methodological aspects, all items were designed on the basis of the theory of planned behavior. In an online questionnaire with N = 595 respondents, it was found that online privacy concerns were not significantly related to specific privacy behaviors, such as the frequency or content of disclosures on SNSs (e.g., name, cell-phone number, or religious views). This demonstrated that the privacy paradox still exists when it is operationalized as in prior research. With regard to the new approach, all hypotheses were confirmed: Results showed both a direct relation and an indirect relation between privacy attitudes and privacy behaviors, the latter mediated by privacy intentions. In addition, also an indirect relation between privacy concerns and privacy behaviors was found, mediated by privacy attitudes and privacy intentions. Therefore, privacy behaviors can be explained sufficiently when using privacy attitudes, privacy concerns, and privacy intentions within the theory of planned behavior. The behaviors of SNS users are not as paradoxical as was once believed. Copyright © 2014 John Wiley & Sons, Ltd.

The Use of Biostimulants for Enhancing Nutrient Uptake

Abstract: Fertilizer use in modern agriculture is highly inefficient; much of the applied fertilizer is released into the environment, causing environmental degradation. One way in which fertilizer use can be reduced without damaging plant nutrition is to enhance crop uptake of nutrients through the use of biostimulants. A broad definition of plant biostimulants, including substances sometimes categorized as biofertilizers or biopesticides, is used throughout this review: “Plant biostimulants are substances or materials, with the exception of nutrients and pesticides, which, when applied to plants, seeds, or growing substrates in specific formulations, have the capacity to modify physiological processes in plants in a way that provides potential benefits to growth, development, or stress response.” This definition includes a variety of substances, four of which will be reviewed in this article: seaweed extract, humic substances, amino acids, and plant-growth-promoting bacteria. We will concentrate on the positive effects of biostimulant application on plant nutrient uptake, and the underlying mechanisms, which include positive changes in soil structure or nutrient solubility, root morphology, plant physiology, and symbiotic relationships, will be discussed. Recommendations for future research directions include finding the most promising substances, isolating the active ingredients and clearly demonstrating the mechanisms by which they affect nutrient uptake. The beneficial effects and mechanisms must be consistently demonstrated in greenhouse and field experiments.

Effects of surgical and dietary weight loss therapy for obesity on gut microbiota composition and nutrient absorption.

Abstract: Evidence suggests a correlation between the gut microbiota composition and weight loss caused by caloric restriction. Laparoscopic sleeve gastrectomy (LSG), a surgical intervention for obesity, is classified as predominantly restrictive procedure. In this study we investigated functional weight loss mechanisms with regard to gut microbial changes and energy harvest induced by LSG and a very low calorie diet in ten obese subjects (n = 5 per group) demonstrating identical weight loss during a follow-up period of six months. For gut microbiome analysis next generation sequencing was performed and faeces were analyzed for targeted metabolomics. The energy-reabsorbing potential of the gut microbiota decreased following LSG, indicated by the Bacteroidetes/Firmicutes ratio, but increased during diet. Changes in butyrate-producing bacterial species were responsible for the Firmicutes changes in both groups. No alteration of faecal butyrate was observed, but the microbial capacity for butyrate fermentation decreased following LSG and increased following dietetic intervention. LSG resulted in enhanced faecal excretion of nonesterified fatty acids and bile acids. LSG, but not dietetic restriction, improved the obesity-associated gut microbiota composition towards a lean microbiome phenotype. Moreover, LSG increased malabsorption due to loss in energy-rich faecal substrates and impairment of bile acid circulation. This trial is registered with ClinicalTrials.gov NCT01344525.

What makes good antioxidants in lipid-based systems? The next theories beyond the polar paradox.

Abstract: The polar paradox states that polar antioxidants are more active in bulk lipids than their nonpolar counterparts, whereas nonpolar antioxidants are more effective in oil-in-water emulsion than their polar homologs. However, recent results, showing that not all antioxidants behave in a manner proposed by this hypothesis in oil and emulsion, lead us to revisit the polar paradox and to put forward new concepts, hypotheses, and theories. In bulk oil, new evidences have been brought to demonstrate that the crucial site of oxidation is not the air-oil interface, as postulated by the polar paradox, but association colloids formed with traces of water and surface active molecules such as phospholipids. The role of these association colloids on lipid oxidation and its inhibition by antioxidant is also addressed as well as the complex influence of the hydrophobicity on the ability of antioxidants to protect lipids from oxidation. In oil-in water emulsion, we have covered the recently discovered non linear (or cut-off) influence of the hydrophobicity on antioxidant capacity. For the first time, different mechanisms of action are formulated in details to try to account for this nonlinear effect. As suggested by the great amount of biological studies showing a cut-off effect, this phenomenon could be widespread in dispersed lipid systems including emulsions and liposomes as well as in living systems such as cultured cells. Works on the cut-off effect paves the way for the determination of the critical chain length which corresponds to the threshold beyond which antioxidant capacity suddenly collapses. The systematic search for this new physico-chemical parameter will allow designing novel phenolipids and other amphiphilic antioxidants in a rational fashion. Finally, in both bulk oils and emulsions, we feel that it is now time for a paradigm shift from the polar paradox to the next theories.

Water – A magic solvent for biomass conversion

Abstract: Hydrothermal biomass conversion processes provide the opportunity to use feedstocks with high water content for the formation of energy carriers or platform chemicals. The water plays an active role in the processes as solvent, reactant and catalyst or catalyst precursor. In this paper, the different hydrothermal processes of carbonization, gasification and liquefaction are introduced and the specific role of water is discussed for each of them. The high reactivity of the polar components of biomass in hot compressed water and its changing properties with temperature are the key to obtain high selectivities of the desired products. Despite the obvious advantages of hydrothermal conversion examples for industrial applications are rare. The main reason for not commercial application of water in the high temperature state is that there are no products that can be sold with profit and cannot be produced cheaper, with less capital risk, and with more simple processes.

REVIEW: Predictive ecology in a changing world

Abstract: 1. In a rapidly changing world, ecology has the potential to move from empirical and conceptual stages to application and management issues. It is now possible to make large-scale predictions up to continental or global scales, ranging from the future distribution of biological diversity to changes in ecosystem functioning and services. With these recent developments, ecology has a historical opportunity to become a major actor in the development of a sustainable human society. With this opportunity, however, also comes an important responsibility in developing appropriate predictive models, correctly interpreting their outcomes and communicating their limitations. There is also a danger that predictions grow faster than our understanding of ecological systems, resulting in a gap between the scientists generating the predictions and stakeholders using them (conservation biologists, environmental managers, journalists, policymakers). 2. Here, we use the context provided by the current surge of ecological predictions on the future of biodiversity to clarify what prediction means, and to pinpoint the challenges that should be addressed in order to improve predictive ecological models and the way they are understood and used. 3. Synthesis and applications. Ecologists face several challenges to ensure the healthy development of an operational predictive ecological science: (i) clarity on the distinction between explanatory and anticipatory predictions; (ii) developing new theories at the interface between explanatory and anticipatory predictions; (iii) open data to test and validate predictions; (iv) making predictions operational; and (v) developing a genuine ethics of prediction.

In vitro bioaccessibility of carotenoids, flavonoids, and vitamin C from differently processed oranges and orange juices [Citrus sinensis (L.) Osbeck].

Abstract: Carotenoid, flavonoid, and vitamin C concentrations were determined in fresh orange segments and a puree-like homogenate derived thereof, as well as freshly squeezed, flash-pasteurized, and pasteurized juices. Lutein and β-cryptoxanthin were slightly degraded during dejuicing, whereas β-carotene levels were retained. Vitamin C levels remained unaffected, whereas flavonoid levels decreased 8-fold upon juice extraction, most likely due to the removal of flavonoid-rich albedo and juice vesicles. Likewise, the presence of such fibrous matrix compounds during in vitro digestion was assumed to significantly lower the total bioaccessibility (BA) of all carotenoids from fresh fruit segments (12%) as compared to juices (29-30%). Mechanical disruption of orange segments prior to digestion did not alter carotenoid BA, whereas pasteurization of the freshly squeezed juice slightly increased BA by 9-11%. In addition to carotenoid BA, the stabilities of hesperidin, narirutin, and vitamin C including dehydroascorbic acid during in vitro digestion were monitored, and applied analytical methods were briefly validated.

Effects of anaerobic digestion on soil carbon and nitrogen turnover, N emissions, and soil biological activity. A review

Abstract: Sustainability in agriculture means the inclusion of several aspects, as sustainable agriculture systems must not compromise not only their ability to satisfy future needs by undermining soil fertility and the natural resource base but also sustainable agriculture has had to address a range of other issues including energy use, efficient use, and recycling of nutrients, the effects on adjacent ecosystems including the effects on water bodies and climate change. Organic manures are an important factor to keep the soil fertility level of soils. However, their management is often related to large emissions. In this context, anaerobic digestion is—similarly to composting—a treatment option for stabilization of biogenic wastes leading to a residual product called digestates, enabling the sanitation and the recycling and use as fertilizer. It is also a means to obtain energy from wastes as well as from dedicated energy crops. Therefore, anaerobic digestion potentially addresses several aspects of agricultural sustainability. This review discusses the current state of knowledge on the effects of anaerobic digestion on organic compounds in digestates and the most important processes influencing N emissions in the field, as well as the possible long-term effects on soil microbial biomass and soil fertility. The main findings are that (1) the direct effects of anaerobic digestion on long-term sustainability in terms of soil fertility and environmental impact at the field level are of minor relevance. (2) The most relevant effects of anaerobic digestion on soil fertility as well as on N emissions will be expected from indirect effects related to cropping system changes such as changes in crop rotation, crop acreage, cover cropping, and total amounts of organic manures including digestates. Furthermore, (3) the remaining organic fraction after anaerobic digestion is much more recalcitrant than the input feedstocks leading to a stabilization of the organic matter and a lower organic matter degradation rate after field application, enabling a similar reproduction of the soil organic matter as obtained by direct application of the feedstock or by composting of the feedstock. (4) Regarding emissions, the main direct effect of anaerobic digestion on a farm level is the influence on gaseous emissions during manure or digestate treatment and handling, whereas the direct effects of anaerobic digestion on a field level on emissions (NH3 − and N2O− emissions, NO3 - leaching) are negligible or at least ambiguous. (5) The main direct effects of anaerobic digestion on the field level are short-term effects on soil microbial activity and changes in the soil microbial community. Therefore, in terms of the effects on agricultural sustainability, potential cropping system-based changes induced by introduction of biogas plants are probably much more relevant for the overall performance and sustainability of the cropping system than the direct effects triggered by application of digestates in comparison to the undigested feedstocks. Furthermore, to get the full potential advances from implementation of biogas plants in terms of improvement of the nutrient use efficiency and reduction of greenhouse gas emissions, there is the need to introduce more sophisticated techniques to avoid counteracting effects by pollution swapping, e.g., by gas-tight closure of the digestate stores and direct soil incorporation of the field-applied digestates.

A review of the remote sensing of lower-tropospheric thermodynamic profiles and its indispensable role for the understanding and the simulation of water and energy cycles

Abstract: A review of remote sensing technology for lower-tropospheric thermodynamic (TD) profiling is presented with focus on high accuracy and high temporal-vertical resolution. The contributions of these instruments to the understanding of the Earth system are assessed with respect to radiative transfer, land-surface-atmosphere feedback, convection initiation, and data assimilation. We demonstrate that for progress in weather and climate research, TD profilers are essential. These observational systems must resolve gradients of humidity and temperature in the stable or unstable atmospheric surface layer close to the ground, in the mixed layer, in the interfacial layer – usually characterized by an inversion – and the lower troposphere. A thorough analysis of the current observing systems is performed revealing significant gaps that must be addressed to fulfill existing needs. We analyze whether current and future passive and active remote sensing systems can close these gaps. A methodological analysis and demonstration of measurement capabilities with respect to bias and precision is executed both for passive and active remote sensing including passive infrared and microwave spectroscopy, the global positioning system as well as water-vapor and temperature Raman lidar and water-vapor differential absorption lidar. Whereas passive remote sensing systems are already mature with respect to operational applications, active more » remote sensing systems require further engineering to become operational in networks. However, active remote sensing systems provide a smaller bias as well as higher temporal and vertical resolutions. For a suitable mesoscale network design, TD profiler system developments should be intensified and dedicated observing system simulation experiments should be performed. « less

The role of wildlife in the transmission of parasitic zoonoses in peri-urban and urban areas

Abstract: During the last 100 years in many countries of the world, there have been dramatic changes in natural/rural landscapes due to urbanization. Since many wildlife species are unable to adapt to these alterations in their environment, urbanization is commonly responsible for a decline of biodiversity in areas of urban development. In contrast, some wild animal species are attracted to peri-urban and urban habitats due to the availability of an abundant food supply and the presence of structures in which to shelter. Urban foxes and/or raccoons are common sights in many peri-urban and urban areas of Europe where they can reach far higher population densities than in their natural habitats. The same is true for foxes and dingoes in some urban areas of Australia. Unfortunately, some of these highly adaptable species are also hosts for a number of parasites of public health and veterinary importance. Due to the complexity of many parasitic life cycles involving several host species, the interactions between wild animals, domestic animals and humans are not fully understood. The role of potential hosts for transmission of a zoonotic disease in urban or peri-urban areas cannot be extrapolated from data obtained in rural areas. Since more than 75% of human diseases are of zoonotic origin, it is important to understand the dynamics between wildlife, domestic animal species and humans in urbanized areas, and to conduct more focused research on transmission of zoonotic parasites including arthropod vectors under such conditions.