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- ItemAssessment of continuous vaginal logger-based temperature monitoring in fever-induced gilts(Dubai : Science Publications, 2013) Schmidt, Mariana; Ammon, Christian; Schon, Peter; Manteuffel, Christian; Hoffmann, GundulaThe aim of this study was to identify a low risk method to induce fever in gilts and to evaluate vaginal sensors for temperature monitoring. Therefore, a rhinitis atrophicans vaccine was used to induce fever to evaluate sensors and behavioral patterns. During 11 trials, two of four animals were injected with 2 mL of the vaccine Porcilis AR-T DF (Intervet) and the other two animals were treated with 2 mL of 0.9% NaCl as controls. A temperature logger (TRIX-8, LogTag Recorders, Auckland, New Zealand) was used to continuously monitor the vaginal temperature. Additionally, rectal temperatures were measured four times daily. The water consumption, food intake and locomotion behaviors of the animals were analysed one day before treatment and during the day of the treatment. The vaccine induced fever in all gilts, which occurred approximately 5.87 h after vaccination. The vaginal logger temperatures and the rectal temperatures showed a linear correlation in 21 vaccinated gilts (r = 0.86; p<0.0001) and 22 non-vaccinated gilts (r = 0.65; P<0.0001). The vaginal logger can be continuously used to measure the core temperature. Water intake decreased (p<0.0001) in the gilts with fever, whereas food intake did not change (p = 0.9411). The vaccinated gilts spent 79±16 more minutes per day lying after the vaccination (p<0.001) in comparison to the day before the vaccination. Treatment with this vaccine provides the opportunity to induce fever over a short time period (5.13 h) and mild sickness behavior in gilts to investigate disease indicators.
- ItemHydrothermal carbonization (HTC): Near infrared spectroscopy and partial least-squares regression for determination of selective components in HTC solid and liquid products derived from maize silage(Amsterdam : Elsevier, 2014) Reza, M. Toufiq; Becker, Wolfgang; Sachsenheimer, Kerstin; Mumme, JanNear-infrared (NIR) spectroscopy was evaluated as a rapid method of predicting fiber components (hemicellulose, cellulose, lignin, and ash) and selective compounds of hydrochar and corresponding process liquor produced by hydrothermal carbonization (HTC) of maize silage. Several HTC reaction times and temperatures were applied and NIR spectra of both HTC solids and liquids were obtained and correlated with concentration determined from van-Soest fiber analysis, IC, and UHPLC. Partial least-squares regression was applied to calculate models for the prediction of selective substances. The model developed with the spectra had the best performance in 3–7 factors with a correlation coefficient, which varied between 0.9275–0.9880 and 0.9364–0.9957 for compounds in solid and liquid, respectively. Calculated root mean square errors of prediction (RMSEP) were 0.42–5.06 mg/kg. The preliminary results indicate that NIR, a widely applied technique, might be applied to determine chemical compounds in HTC solid and liquid.
- ItemThe MiLA tool: Modeling greenhouse gas emissions and cumulative energy demand of energy crop cultivation in rotation(Amsterdam : Elsevier, 2016) Peter, Christiane; Specka, Xenia; Aurbacher, Joachim; Peter Kornatz, Peter Kornatz; Herrmann, Christiane; Heiermann, Monika; Müller, Janine; Nendel, ClaasCrop rotations are part of current agricultural practice, since they and their effects can contribute to a sustainable agricultural cropping system. However, in current Life Cycle Assessment (LCA) studies, crop rotation effects are insufficiently considered, since these effects are difficult to measure. LCA studies from crop production typically take only one vegetation period into account. As a result, the consideration of how the assessed crop is influenced by the previous crop (crop rotation effects) including: (1) nutrient carryover, (2) reduction in operational requirements and (3) different intensity and timing of farming activities, is outside of the system boundary. However, ignoring these effects may lead to incorrect interpretation of LCA results and consequently to poor agricultural management as well as poor policy decisions. A new LCA tool called the “Model for integrative Life Cycle Assessment in Agriculture (MiLA)” is presented in this work. MiLA has been developed to assess GHG emissions and cumulative energy demands (CED) of cropping systems by taking the characteristics of crop cultivation in rotation into account. This tool enables the user to analyze cropping systems at farm level in order to identify GHG mitigation options and energy-efficient cropping systems. The tool was applied to a case study, including two crop rotations in two different regions in Germany with the goal of demonstrating the effectiveness of this tool on LCA results. Results show that including crop rotation effects can influence the GHG emission result of the individual crop by − 34% up to + 99% and the CED by − 16 up to + 89%. Expanding the system boundary by taking the whole crop rotation into account as well as providing the results based on different functional units improves LCA of energy crop production and helps those making the assessment to draw a more realistic picture of the interactions between crops while increasing the reliability of the LCA results.
- ItemRisk efficiency of irrigation to cereals in northeast Germany with respect to nitrogen fertilizer(Amsterdam : Elsevier, 2016) Meyer-Aurich, Andreas; Gandorfer, Markus; Trost, Benjamin; Ellmer, Frank; Baumecker, MichaelThe potential role of irrigation of cereals as a response to climate change is under debate. Especially under temperate continental conditions empirical evidence of crop yield response to irrigation in interaction with nitrogen fertilizer supply is rare. Besides mean yield effects, irrigation reduces yield variance, which may be an incentive for farmers to use irrigation. This paper investigates the risk-efficiency of irrigation in cereal production in a temperate continental climate, based on data from a long term field experiment on a sandy soil. Irrigation and no irrigation of winter rye (Secale cereale) and winter barley (Hordeum vulgare) were investigated in three different nitrogen (N) fertilizer levels. Crop yield response data (1995–2010) to irrigation and N fertilizer were used to calculate net returns, certainty equivalents (CE) for different levels of risk aversion and the conditional value at risk (CVaR) as a downside risk indicator in two price scenarios. The scenarios were calculated with a total cost and a partial budget approach. Irrigation was found to be profit-maximizing in all partial budget calculations, which sometimes required higher N input to be profit-maximizing. Irrigation and N fertilizer reduction were identified as risk mitigation strategies, even though their impact was limited. Irrigation reduced the downside risk only in the partial budget calculations. The analysis based on the CE did not show improved risk efficiency with irrigated management options. In contrast, reduced fertilizer input proved to be risk efficient at specific levels of risk aversion. The price expectations of winter rye and winter barley had a much higher impact on the ranking of the management options than risk aversion based on the crop yield variances. At low crop prices for all levels of risk aversion, irrigation of winter barley and winter rye was only economically justified if fixed costs for irrigation were not taken into account. At high crop prices, irrigation of winter barley was also justified based on the total cost calculation. However, this advantage was only given at a very low level of risk aversion. With increasing levels of risk aversion irrigation was not efficient based on the CE in the total cost accounting scenario. In conclusion, irrigation of cereals can contribute to downside risk mitigation and increased profits, if fixed costs for irrigation are covered. However, this conclusion holds only when irrigation is combined with an increased N intensity. If total costs need to be accounted for, irrigation in cereals is not an appropriate risk reduction strategy and a reduction of N input is more effective.
- ItemModeling the water demand on farms(München : European Geopyhsical Union, 2012) Drastig, K.; Prochnow, A.; Kraatz, S.; Libra, J.; Krauß, M.; Döring, K.; Müller, D.; Hunstock, U.The decreasing availability of water caused by depletion and climate change combined with a growing world population requires the productive use of water now and in the future. The young researcher group "AgroHyd" at the Leibniz-Institute for Agricultural Engineering Potsdam-Bornim (ATB) is currently modeling the water demand for agricultural processes at the farm scale and developing indicators to link the hydrological and agricultural perspectives. The aim of the group is to increase productivity in agriculture by raising water productivity in plant production and livestock farming. The effects of various agronomic measures, individual and in combination, on water productivity are assessed using several indicators. Scenarios of agricultural measures, climate and diets are used to test to what extent the water demand for food production will increase due to growing global change in different regions of the world.
- ItemQuantification of nitrogen balance components in a commercial broiler barn(Prague : ČSAZV, 2013) von Bobrutzki, K.; Ammon, S.; Berg, W.; Fiedler, M.Characterizing the respective nitrogen (N) use efficiency requires understanding the N flow of inputs and outputs from a commercial broiler barn. In this study, an N mass balance was performed for one entire growing cycle. The objectives were to quantify, sample, and analyze all N components entering and leaving the barn. The N from feed, chickens, and bedding material was considered as inputs, the outputs included the N accretion in mature broilers, the total N emissions (NTNE), the N accumulation in litter, and the N of mortality. Of particular relevance was the determination of an appropriate method to mirror the heterogenic texture of the litter. Litter samples were collected weekly according to a defined procedure. The major N input was feed N, accounting for 99% of the total N input. After the 36-day growing cycle, the N outputs were portioned as follows: 59% (1741.3 kg N) in mature broilers, 37% (1121.3 kg N) accumulated in litter, and 4% in NTNE (114.3 kg N). The N accumulations in broiler tissue and litter agree well with other studies. The measured emissions were consistently lower compared to other references, due to the fact that these references were mainly based on studies where broilers were raised on built-up litter. In contrast to in situ quantified N emissions in this study, other published values were assumed to be the difference of N between inputs and outputs. This study illustrates that extensive sampling of litter is a prerequisite for calculating litter masses. The accurate specification of the litter texture proved to be crucial within the mass balance approach. With this information, the feasible improvements within management practices can be identified.
- ItemA brief dataset on the model-based evaluation of the growth performance of Bacillus coagulans and l-lactic acid production in a lignin-supplemented medium(Amsterdam : Elsevier, 2017) Glaser, Robert; Venus, JoachimThe data presented in this article are related to the research article entitled “Model-based characterization of growth performance and l-lactic acid production with high optical purity by thermophilic Bacillus coagulans in a lignin-supplemented mixed substrate medium (R. Glaser and J. Venus, 2016) [1]”. This data survey provides the information on characterization of three Bacillus coagulans strains. Information on cofermentation of lignocellulose-related sugars in lignin-containing media is given. Basic characterization data are supported by optical-density high-throughput screening and parameter adjustment to logistic growth models. Lab scale fermentation procedures are examined by model adjustment of a Monod kinetics-based growth model. Lignin consumption is analyzed using the data on decolorization of a lignin-supplemented minimal medium.
- ItemAgricultural Water Management in Brandenburg(Berlin : Gesellschaft für Erdkunde, 2011) Drastig, Katrin; Prochnow, Annette; Baumecker, Michael; Berg, Werner; Brunsch, ReinerThe present study explores whether regional water resources can be used more efficiently by Brandenburg’s agricultural systems. A systematic analysis of measures to raise the water efficiency follows the description of agriculture in Brandenburg today. Brandenburg’s agricultural systems are separated into three sections: soils, plant production and livestock farming. Within these sections measures to increase water efficiency are listed and analysed with reference to five objective criteria for raising water use efficiency. In the soil section the measures soil tillage and humus conservation management are assigned to the criteria. The following fields in the plant production section are similarly investigated: breeding, seeding, fertilisation, tactically chosen crops, avoidance of competition by herbicide use and efficient irrigation practices as well as watersaving storage and cleaning of field crops. In livestock farming the supply of drinking water and cleaning and cooling processes are analysed. In view of the complexity of the agricultural farming systems in Brandenburg, general measures to raise water use efficiency could not be derived. Sitespecific tillage practices and crop patterns adjusted to the recent weather conditions may reflect the specific diversity of Brandenburg more efficiently.
- ItemEffects of storage conditions and duration on physicochemical and microbial quality of the flour of two cassava cultivars (TME 419 and UMUCASS 36)(Milton Park : Taylor & Francis, 2015) Uchechukwu-Agua, Amarachi D.; Caleb, Oluwafemi J.; Manley, Marena; Opara, Umezuruike LinusThis study investigated the effects of storage conditions: cool (15 ± 1°C, 90% relative humidity (RH)), ambient (23 ± 2°C, 60% RH) and higher (38 ± 2°C, 60% RH) on changes in physicochemical quality attributes of two cassava flour cultivars (TME 419 and UMUCASS 36) packaged in paper bags and stored for 12 weeks. Physicochemical and microbial qualities were studied at weeks 0, 4, 8 and 12. Moisture content decreased from 12.0% to 7.1% and 9.8% to 6.8% in cultivars ‘TME 419’ and ‘UMUCASS 36’, respectively. Carotenoid content was higher in cultivar (cv.) ‘UMUCASS 36’ (2.5 ± 0.10 mg/g) compare to cv. ‘TME 419’ (1.8 ± 0.11 mg/g). Colour indices of the cassava flour were significantly influenced by storage duration. A slight decrease in microbial load from 5.4 to 4.8 log CFU/g was observed, with increase in temperature from 15°C to 38°C at the end of storage. The ambient storage condition best maintained nutritional and physicochemical quality.
- ItemEnzyme-based lignocellulose hydrolyzation – Brief data survey for cellulase performance characterization on behalf of the Sauter mean diameter of raw material particles(Amsterdam : Elsevier, 2015) Glaser, RobertThe data presented here supports the informational background of enzyme-based lignocellulose hydrolyzation, cellulase characterization, and sugar yield prediction for the work “Enzyme-based lignocellulose hydrolyzation – Sauter mean diameter of raw materials as a basis for cellulase performance characterization and yield prediction” by Glaser [1]. Glucose yields from the enzymatic hydrolysis of the raw materials were shown as a function of cellulase enzyme loading as well as of particle size with different solid loading. The data for the proposed methods of the determination of enzyme activity in inhomogeneous samples of lignocellulosic raw materials are presented. The data of the empirical model that was developed for the prediction of hydrolysis yields for different enzyme concentrations, substrate specific particle size, and solid loadings, are given. Data are also given in relation of terms of scale-up opportunities.