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.
2019
Abstract
No abstract has been registered
Abstract
Edible seaweed biomass is a valuable alternative feed ingredient for livestock. The composition of seaweeds is highly variable, with large differences in proteins, minerals, lipids and carbohydrates. Species, season, harvesting year, habitat, and prevailing proximate environmental conditions account for this variation. Using seaweeds as a protein source for production animals is of interest. Studies suggest that some seaweed species may have bioactive compounds with antimethanogenic properties. To investigate the effect of the red seaweed Porphyra ssp on enteric methane produced by sheep an in vivo study was carried out with 24 Norwegian White ewes. The ewes were allocated into four groups receiving a control diet or one of three supplemented diets. All groups were fed grass silage ad libitum, crushed oat and mineral pellets; the three supplemented diets included a protein source where dried and powdered Porphyra ssp. was compared with white clover silage or pelleted soybean meal. The ewes were fed their respective diets for a two-week adaptation period and a 72-h experimental period during which methane was measured individually using open-circuit respiration chambers. Weight changes and methane production (L CH4/kg DM intake) were analysed using the GLM procedure with diet as fixed effect. No differences in weight changes and methane production between diets were found. Diet did not affect weight changes and methane production but DM intake was higher (P<0.001) for diets including soybean and macroalgae than white clover. Feeding red macroalgae showed no reduction in enteric methane production compared to the control diet.
Abstract
In this study, a brown macroalgae species, Saccharina latissima, processed to increase its protein concentration, and a red macroalgae species, Porphyra spp., were used to evaluate their in vivo digestibility, rumen fermentation and blood amino acid concentrations. Four castrated rams were used, whose diets were supplemented with a protein-rich fraction of S. latissima, a commercial Porphyra spp. and soybean meal (SBM). Our results show that the protein digestibility of a diet with S. latissima extract was lower (0.55) than those with Porphyra spp. (0.64) and SBM (0.66). In spite of the higher nitrogen (N) intake of diets containing Porphyra spp. and SBM (20.9 and 19.8 g N/day, respectively) than that with S. latissima (18.6 g N/day), the ratio of N excreted in faeces to total N intake was significantly higher in the diet with S. latissima than those with Porphyra spp. and SBM. This reflects that the utilization of protein in S. latissima was impaired, possibly due to reduced microbial activity. The latter statement is corroborated by lower volatile fatty acid composition (25.6, 54.8 and 100 mmol/l for S. latissima, Porphyra spp. and SBM, respectively) and a non-significant tendency for lower ammonia concentration observed in diets with S. latissima and Porphyra spp. compared to SBM. It is important to note that the S. latissima used in this trial was rinsed during processing to remove salt. This process potentially also removes other water-soluble compounds, such as free amino acids, and may have increased the relative fraction of protein resistant to rumen degradation and intestinal absorption. Furthermore, the phlorotannins present in macroalgae may have formed complexes with protein and fibre, further limiting their degradability in rumen and absorption in small intestines. We recommend that further studies explore the extent to which processing of macroalgae affects its nutritive properties and rumen degradability, in addition to studies to measure the intestinal absorption of these macroalgae species
Authors
Steffen AdlerAbstract
No abstract has been registered
Abstract
Minimising outputs of waste and pollution by recycling and efficient utilisation of renewable resources is of common interest for organic agriculture and the concepts of circular and bioeconomy. However, in practice, many efforts to increase recycling of various biological materials in organic agriculture are hampered because standards for certified organic production and processing tend to prefer natural products while avoiding processing and especially chemical processes. This creates several dilemmas and weakens the position of organic agriculture as a spear head in the development of a better resource utilisation which will reduce environmental impacts from food production. Based on practical examples derived from projects aimed at better utilisation of residual materials in various food chains, this paper presents some of these dilemmas. Our aim is to initiate a discussion among organic agriculture stakeholders about the regulations for organic production, how they restrict recycling and a better utilisation of valuable resources, and how this can be overcome.
Abstract
No abstract has been registered
Authors
Xiao Huang Chaoqing Yu Tongbi Tu Shaoqiang Ni ShengChao Qiao Jim W Hall Mats Höglind Hanna Marika SilvennoinenAbstract
In the past decade, China imported massive quantities of soybean from the international market to meet its increasing domestic demand for protein[1]. However, China’s soybean imports from US decreased from 32.86 Mt (Million tons, 34% of the total 95.54 Mt) in 2017 to 16.64 Mt (19% of the total 88.03 Mt) in 2018[2] due to the China-US trade war. To reduce China’s reliance on imports, the Chinese government has been making policy incentive, e.g. higher subsidies, to encourage farmers for soybean cultivation. Traditionally Northeast China is the key production area for soybean. Soybean cultivation is tightly linked to the regional climate and environment. On the one hand, the local soybean growth is vulnerable[3] to the frequent meteorological hazards (e.g. droughts, floods) in the Northeast China[4]. The meteorological risks for soybean production in this area still remain unknown. On the other hand, albeit with relatively high production cost[5] and low water use efficiency[6], the local soybean cultivation is expected to effectively improve the nitrogen use efficiency and therefore alleviate the growing environment pollutions in this region[7]. Yet so far there are few quantitative research being reported on this environmental issue. Our research aims to explore both the meteorological risks and environmental costs of the policy-driven soybean expansion. We have developed a new version of the soybean growth algorithms within the DNDC (DeNitrification-DeComposition) model including nitrogen biogeochemical processes and performed regional simulations for soybean-related cropping systems in Northeast China. We will present the following results by combining model outputs and observations: (i) potential yield and the meteorological risks of soybean cultivation; (ii) fertilizer reduction in different crop rotation systems and the corresponding benefits to water ecosystem; and (iii) consequences of different policy scenarios (e.g. change in subsidy, GMO permission) to soybean production and environment.
Abstract
Pastures are botanically diverse and difficult to characterize. Digital modeling of pasture biomass and quality by non-destructive methods can provide highly valuable support for decision-making. This study aimed to evaluate aerial and on-ground methods to characterize grass ley fields, estimating plant height, biomass and volume, using digital grass models. Two fields were sampled, one timothy-dominant and the other ryegrass-dominant. Both sensing systems allowed estimation of biomass, volume and plant height, which were compared with ground truth, also taking into consideration basic economical aspects. To obtain ground-truth data for validation, 10 plots of 1 m2 were manually and destructively sampled on each field. The studied systems differed in data resolution, thus in estimation capability. There was a reasonably good agreement between the UAV-based, the RGB-D-based estimates and the manual height measurements on both fields. RGB-D-based estimation correlated well with ground truth of plant height (R 2 > 0.80) for both fields, and with dry biomass (R 2 = 0.88), only for the timothy field. RGB-D-based estimation of plant volume for ryegrass showed a high agreement (R 2 = 0.87). The UAV-based system showed a weaker estimation capability for plant height and dry biomass (R 2 < 0.6). UAV-systems are more affordable, easier to operate and can cover a larger surface. On-ground techniques with RGB-D cameras can produce highly detailed models, but with more variable results than UAV-based models. On-ground RGB-D data can be effectively analysed with open source software, which is a cost reduction advantage, compared with aerial image analysis. Since the resolution for agricultural operations does not need fine identification the end-details of the grass plants, the use of aerial platforms could result a better option in grasslands.
Abstract
This study aimed at identifying optimal sward conditions for successful establishment of red clover (Trifolium pratense L.) through sod-seeding two typical Norwegian grassland systems dominated by timothy (Phleum pratense L.) and perennial ryegrass (Lolium perenne L.), respectively. A total of four sod-seeding trials were implemented, two in late summer (SUM) and two in spring (SPR), one for each sward type and time point for reseeding. The sward coverage status was the basis for threshold definition, and image analysis techniques were used for objective coverage estimation of living plants, dead material and bare soil. Plots with different coverage levels (0–100% of the soil covered by vegetation) were created by spraying a broad-spectrum herbicide (glyphosate) in a spot-wise pattern, mimicking common types of patchiness caused by stressful weather events, e.g., frost or mechanical damage from wheels or hoofs. Seed germination and emergence started similarly in all coverage ranges. However, as time progressed clover seedlings started to die at a coverage dependent rate, and at the final harvest red clover dry matter (RCDM) was the lowest on plots with the highest pre-seeding coverage level. Dose-response curves explained these relationships and allowed estimating the effective-coverage ( ECov80 ), being the initial sward coverage at which 80% of all established red clover plants contributed significantly to the total biomass. Above 2500 kg ha−1 RCDM were produced on timothy ( ECov80 : 15–50%) in SUM, while less than 1000 kg ha−1 RCDM were produced on ryegrass ( ECov80:±10% ), indicating better conditions for clover establishment in timothy compared with ryegrass. In SPR, an ECov80 : 10–15% allowed a good red clover estabishment in ryegrass at cut 3, while RCDM was important and significant in timothy even between ECov80 20 and 60%, at cut 2 and cut 3, respectively. These thresholds for sod-seeding mark the challenges to introduce red clover in dense swards and could be applicable for grassland renovation with other desirable legume and grasses species. Our findings represent particular soil and climatic characteristics of the study site, thus should be taken with caution. Due to the lack of experimentally and sytematically determined thresholds for reseeding, future studies could benefit from our experimental approach, as a base for more complex, multi-site and multi-seasonal investigations, and farmers could use these thresholds for decision making on successful grassland renovation, to avoid wasting seed resources and yield loses.
Abstract
No abstract has been registered