Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2024
Forfattere
Ellen ElverlandSammendrag
Det er ikke registrert sammendrag
Forfattere
Ellen ElverlandSammendrag
Det er ikke registrert sammendrag
Forfattere
Mohammad Tirgariseraji A. Pouyan Nejadhashemi Yaghoob Jafari Tomas Persson Mahmood Sabouhi Sabouni Alisher Mirzabaev Alireza Nikouei Naser Shahnoushi FroshaniSammendrag
The nitrogen regulatory policy (NRP) solution is introduced as a mitigation measure against environmental nitrogen losses and keeps food production in the Safe Operating Space of the Nitrogen Planetary Boundary. Meanwhile, scientific research shows that steps taken to reduce environmental harm can increase the unpredictability of calorie production from crops. This study sought to investigate the impact of NRP solutions on the level of risk of accessibility to calorie sources from domestic production, the variations in calorie sources by livestock and non-livestock diet components, and the responses of different dietary preferences, namely, poor, medium, and rich livestock protein diets, against NRP solutions in the Zayandeh-Rud River basin, Iran. We developed the aggregate household food security index (AHFSI) and combined it with outputs of crop simulation model to examine how changes in dietary energy supplies under three NRP scenarios—low, moderate, and high nitrogen fertilizer application—affect the stability of three regional dietary preferences. The comparison of NRP scenarios movements realized that increases (or decreases) in nitrogen fertilizer rates contradicted the stability in AHFSI. Additionally, a one-unit change in the average calories from non-livestock sources, such as wheat and potatoes, results in greater fluctuations in the standard deviations of produced calories compared to changes in meat and dairy production. We proposed that in order to prevent adverse effects of NRP solutions on food security, mitigation strategies addressing the NRP solution should be structured based on (i) regional heterogeneities, (ii) type of crops, that is, food and feed crops, (iii) the range of nitrogen rates movement; (iv) and the socioeconomic background related to dietary preferences or economic deciles of food expenditure.
Sammendrag
Manure spreading often leads to nutrient losses with negative environmental impacts, especially in cold climates where harsh winters can affect grass sward density. Nutrient efficiency in cattle slurry depends on the plant coverage at the start of the growing season. To simulate winter damage variation, random mechanical disturbance was applied to a grass field. Aerial images were obtained and analysed using the Grasision® tool to estimate plant cover. Three fixed treatments with uniform cattle slurry and N fertilizer application across all plots, and two treatments adjusting slurry and N fertilizer based on autumn or spring plant coverage were tested. Above-ground yield was measured post-first and second cut. Adjusting N rates based on spring plant coverage or using a low N rate resulted in similar agronomic N use efficiency as high N application rates, albeit with lower dry matter yield.
Sammendrag
Interest in dairy cow-calf contact (CCC) systems is growing, yet limited research had been focused on CCC in a pasture setting. Our study aimed to evaluate the performance of pastured dairy cows and calves with or without CCC through machine milk yield and composition, cow body condition score (BCS) and body weight (BW) decrease, and calf body weight gain (BWG). We also examined calf intake of concentrates, artificially reared calves’ milk intake, and the health of both cows and calves. Conducted on a commercial dairy freestall farm and summer farm in Norway from May to August 2021, the study included twenty cow-calf pairs: 17 Norwegian Red (NRF) and three NRF × Holstein crossbreeds. They were divided into two treatments: cow-calf contact (CC, n = 10) or early separation (ES, n = 10), each with two groups of five cow-calf pairs. CC pairs had full CCC on pasture until 6 weeks postpartum and part-time contact in weeks 7 and 8 (weaning). ES pairs were separated 1–3 h after birth, kept on separate pastures with no contact between ES cows and calves. ES calves’ received daily milk allowances of 12–14 L (weeks 0–6), reduced to 8 L (week 7) and further to 4 L (week 8). From week 9, all calves were denied access to any milk (ES) or cows (CC). During weeks 0–6, CC cows had a daily machine milk yield 23.7 kg lower/cow than ES cows. The difference was likely affected by nursing and other factors (parity and inhibited milk ejection), and persisted during weaning, with CC cows delivering 8.3 kg less/cow/day in weeks 10 and 11 postpartum. Fat and protein content in machine milk showed no significant difference, while lactose content was lower in milk from CC cows than ES cows (week 5 postpartum). CC cows had a lower BW decrease compared to ES cows (CC: 913 g/day, ES: 1415 g/day from pasture day one through week 9). ES calves had an average milk intake of 10.7 L/calf/day (weeks 0–6), and consumed more concentrates than CC calves. Calves’ daily BWG did not differ between treatments in weeks 0–6 (CC: 1340 and ES: 1250 g/day) and decreased for both treatments during weaning (CC: 1050 g/day, ES: 920 g/day in weeks 6–9). Inhibited milk ejection during machine milking was a challenge in CC cows, prompting oxytocin injections to prevent mastitis. Allowing calves full CCC or providing whole milk near ad libitum can result in similar BWG and health in calves. Further research should explore strategies to enhance milk ejection in pastured CCC cows.
Forfattere
Sigridur DalmannsdottirSammendrag
Det er ikke registrert sammendrag
Forfattere
Thomas Georges A Bawin Marte Marie Fossum Ranvik Sigridur Dalmannsdottir Egle Norkeviciene Rita Armonienė Erik Alexandersson Laura Elina JaakolaSammendrag
Climate change is increasingly affecting agricultural systems, impacting the productivity and digestibility of forage crops that are essential for livestock feed. Understanding how forage crops respond to temperature is crucial for optimizing growth and nutritional value. Remote sensing technologies offer promising tools for monitoring plant health and predicting forage quality. As part of the project UPSCALE, this study examines the growth and spectral response of Northern and Southern cultivars under different temperature regimes. Two red clover (ʻGandalfʼ from Norway and ʻVytisʼ from Lithuania) and two timothy (ʻNorengʼ from Norway and ʻJauniaiʼ from Lithuania) cultivars were grown at controlled temperatures of 12, 15, and 18°C. A total of 168 pots (10L, ~30 plants per pot) were maintained in climate-controlled chambers at The Climate Laboratory, UiT, Tromsø. Plant growth was monitored using the PlantEye F600, providing 3D models, biomass, height, leaf area index, and stress indices (NDVI, NPCI, PSRI). Destructive sampling was conducted at three stages: pre-flowering, post-flowering, and at the end of the experiment. Leaves were scanned using Specim FX10e (VNIR) and FX17e (SWIR) hyperspectral cameras before drying for chemical analysis. Results showed distinct growth differences among the cultivars. Clovers increased in height and biomass with rising temperatures, though ʻGandalfʼ consistently yielded less biomass. Timothy ʻJauniaiʼ followed a similar trend to the clovers, while cultivar ʻNorengʼ had optimal growth at 15°C. Spectral indices did not reveal significant contrasts; ongoing hyperspectral analysis may provide further insights. The upcoming chemical analysis will integrate with hyperspectral data to identify lignin signatures for assessing forage digestibility. These findings contribute to a deeper understanding of how forage crops respond to temperature variations, to select cultivars with optimal growth and digestibility in the face of climate change.
Forfattere
Sigridur DalmannsdottirSammendrag
Det er ikke registrert sammendrag
Forfattere
Thomas Georges A Bawin Marte Marie Fossum Ranvik Sigridur Dalmannsdottir Egle Norkeviciene Rita Armonienė Erik Alexandersson Laura Elina JaakolaSammendrag
Det er ikke registrert sammendrag
Forfattere
Synnøve RivedalSammendrag
Det er ikke registrert sammendrag