Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2016
Authors
Zhibo HamborgAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Juliet Biira Jens Leth Hougaard Mogens LundAbstract
Denmark is one of the EU countries with a highly recognised agricultural sector, a high level of animal health and one of the lowest medication usages. In this article we aim to provide an overview of both private and public animal health incentives nested in the cattle and pig production industry that influence the decisions and behaviours of farmers in prevention of livestock disease epidemics. Not only do individual Danish pig and cattle farmers aim at highly efficient animal production, they are also involved in collective marketing and contracting which can enhance social capital, peer pressure and instill a greater sense of ownership of disease control prevention. Public incentives including rules on how animals should be transported within Denmark, SPF certification requirements and rules on farm biosecurity further improve farmer incentives to prevent animal diseases. However, Danish pig and cattle farmers’ incentives could be further improved by specifying consequences for not following requirements such as failure to make a compulsory biosecurity plan. The relatively high compensation in case of a disease outbreak provides a safety net for farmers, encourages them to quickly report suspected notifiable diseases but it could also reduce incentives for disease prevention due to the relatively high amounts of compensation.
Abstract
No abstract has been registered
Authors
Biancha CavicchiAbstract
No abstract has been registered
Abstract
Process-based models (PBM) for simulation of weather dependent grass growth can assist farmers andplant breeders in addressing the challenges of climate change by simulating alternative roads of adap-tation. They can also provide management decision support under current conditions. A drawback ofexisting grass models is that they do not take into account the effect of winter stresses, limiting theiruse for full-year simulations in areas where winter survival is a key factor for yield security. Here, wepresent a novel full-year PBM for grassland named BASGRA. It was developed by combining the LIN-GRA grassland model (Van Oijen et al., 2005a) with models for cold hardening and soil physical winterprocesses. We present the model and show how it was parameterized for timothy (Phleum pratense L.),the most important forage grass in Scandinavia and parts of North America and Asia. Uniquely, BASGRAsimulates the processes taking place in the sward during the transition from summer to winter, includ-ing growth cessation and gradual cold hardening, and functions for simulating plant injury due to lowtemperatures, snow and ice affecting regrowth in spring. For the calibration, we used detailed data fromfive different locations in Norway, covering a wide range of agroclimatic regions, day lengths (latitudesfrom 59◦to 70◦N) and soil conditions. The total dataset included 11 variables, notably above-ground drymatter, leaf area index, tiller density, content of C reserves, and frost tolerance. All data were used inthe calibration. When BASGRA was run with the maximum a-posteriori (MAP) parameter vector fromthe single, Bayesian calibration, nearly all measured variables were simulated to an overall normalizedroot mean squared error (NRMSE) < 0.5. For many site × experiment combinations, NRMSE was <0.3. Thetemporal dynamics were captured well for most variables, as evaluated by comparing simulated timecourses versus data for the individual sites. The results may suggest that BASGRA is a reasonably robustmodel, allowing for simulation of growth and several important underlying processes with acceptableaccuracy for a range of agroclimatic conditions. However, the robustness of the model needs to be testedfurther using independent data from a wide range of growing conditions. Finally we show an exampleof application of the model, comparing overwintering risks in two climatically different sites, and dis-cuss future model applications. Further development work should include improved simulation of thedynamics of C reserves, and validation of winter tiller dynamics against independent data.
Authors
Johanna Gottschamel Andreas G. Lössl Stephanie Ruf Yanliang Wang Morten Skaugen Ralph Bock Jihong Liu ClarkeAbstract
Abstract Dengue fever is a disease in many parts of the tropics and subtropics and about half the world’s popula- tion is at risk of infection according to the World Health Organization. Dengue is caused by any of the four related dengue virus serotypes DEN-1, -2, -3 and -4, which are transmitted to people by Aedes aegypti mosquitoes. Cur- rently there is only one vaccine (DengvaxiaÒ) available (limited to a few countries) on the market since 2015 after half a century’s intensive efforts. Affordable and accessible vaccines against dengue are hence still urgently needed. The dengue envelop protein domain III (EDIII), which is capable of eliciting serotype-specific neutralizing antibod- ies, has become the focus for subunit vaccine development. To contribute to the development of an accessible and affordable dengue vaccine, in the current study we have used plant-based vaccine production systems to generate a dengue subunit vaccine candidate in tobacco. Chloroplast genome engineering was applied to express serotype- specific recombinant EDIII proteins in tobacco chloroplasts using both constitutive and ethanol-inducible expression systems. Expression of a tetravalent antigen fusion con- struct combining EDIII polypeptides from all four ser- otypes was also attempted. Transplastomic EDIII- expressing tobacco lines were obtained and homoplasmy was verified by Southern blot analysis. Northern blot analyses showed expression of EDIII antigen-encoding genes. EDIII protein accumulation levels varied for the different recombinant EDIII proteins and the different expression systems, and reached between 0.8 and 1.6 % of total cellular protein. Our study demonstrates the suitability of the chloroplast compartment as a production site for an EDIII-based vaccine candidate against dengue fever and presents a GatewayÒ plastid transformation vector for inducible transgene expression.
Authors
Habtamu AlemAbstract
No abstract has been registered
Abstract
Effects of wilting rate and fermentation stimulators and inhibitors on protein characteristics of forages typ- ical for organic production were assessed using tradi- tional analytical methods and a gas production in vitro assay. The hypotheses were that the proportion of the crude protein (CP) fraction that was soluble would be lowest, and the protein feed value highest, under rapid wilting and restricted fermentation. The solubil- ity of the CP fraction varied according to treatments and between a first and a second cut, with moderate and high content of clover respectively. It was, how- ever, of minor importance for the protein value, both calculated as amino acids absorbed in the small intes- tine (AAT 20 ) and estimated as effective utilizable crude protein (uCP 04 ) by the in vitro assay. In ensiled her- bage, AAT 20 was highest in rapidly wilted and restrict- edly fermented silages made from a first cut dominated by highly digestible grasses. Silages from the second cut dominated by red clover were far lower in AAT 20 . The in vitro assay did not separate silages according to herbage composition or wilting rate, but ranked restrictedly fermented above extensively fer- mented with regard to protein supply. The assay might still have caught the characteristics that determine the true protein value in vivo.