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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.

2025

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Abstract

VKM has assessed the risk of introduction and spread of bovine tuberculosis in Norway and cannot rule out that the disease still exists in Norway. There is a low risk of the disease being reintroduced with imported cattle, but the import of llamas and alpacas poses a greater risk. If the disease were to establish in Norway, there is a high risk of spread both among domestic animals and to wildlife. These are the main conclusions The Norwegian Scientific Committee for Food and Environment (VKM) has made in a risk assessment commissioned by the Norwegian Food Safety Authority. Background Following the outbreak of bovine tuberculosis in 2022, VKM was asked to investigate the risk of introduction as well as the risk of spread and establishment of the disease in Norway. The disease primarily affects cattle, but other animals and humans can also be affected. Bovine tuberculosis is a chronic disease that is difficult to diagnose. Therefore, it may take months or years before infected animals are detected. This makes it challenging to eradicate the disease. Conclusions With today's very limited import, VKM concludes it is unlikely that bovine tuberculosis will be introduced to Norway with cattle. Since neighboring countries Sweden and Finland are free from the disease, migration of wildlife will not pose a risk of introduction. However, as the source of the 2022 outbreak has not been identified, it cannot be determined if the disease is still present in Norway. “Alpacas and llamas pose a greater risk. These species are particularly susceptible to the disease, and animals have been imported to Norway, also from countries where the bacterium is common in the cattle population. It is therefore likely that the bacterium could be introduced to Norway with these species if imports continue”, says Eystein Skjerve, Scientific leader of the project team. There is significant trade and transportation of live animals (cattle, alpacas, and llamas) within Norway. If bovine tuberculosis were to establish here, such movements would pose a significant risk of spreading the bacterium. Furthermore, manure from infected herds could pose a risk of spreading to livestock and wild animals. Additionally, contact between livestock and wild animals, such as badgers, wild boars, and various deer species, could lead to the spread of the disease to the wild population. If bovine tuberculosis is established in Norway, a control and eradication strategy would require considerable time and resources. If the disease is introduced to-, and established in wild animal populations, experience from other countries indicates that it will be very challenging to eradicate the disease. “The risk of transmission of bovine tuberculosis to humans is generally low. Veterinarians, farmers, and slaughterhouse workers have an increased risk of infection. If the disease is established in Norway, the greatest risk of transmission to humans is through the consumption of both unpasteurised milk and dairy products”, Skjerve says. Risk-Reducing Measures VKM was also asked to identify several measures that could reduce the risk of introduction and establishment of bovine tuberculosis in Norway: Avoid importing animals from countries and regions where bovine tuberculosis is present in livestock. Avoid importing roughage to Norway from countries and regions with bovine tuberculosis. Increase testing requirements for the trade and movement of alpacas and llamas inside Norway. In the event of an outbreak of bovine tuberculosis, reduce contact between livestock and wild animals and routinely test wild animals (badgers, wild boars, and deer species). (...)

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Abstract

Plant secondary metabolites (PSMs) may improve gastrointestinal health by exerting immunomodulatory, anti-inflammatory and/or antiparasitic effects. Bark extracts from coniferous tree species have previously been shown to reduce the burden of a range of parasite species in the gastrointestinal tract, with condensed tannins as the potential active compounds. In the present study, the impact of an acetone extract of pine bark (Pinus sylvestris) on the resistance, performance and tolerance of genetically diverse mice (Mus musculus) was assessed. Mice able to clear an infection quickly (fast responders, BALB/c) or slowly (slow responders, C57BL/6) were infected orally with 200 infective third-stage larvae (L3) of the parasitic nematode Heligmosomoides bakeri or remained uninfected (dosed with water only). Each infection group of mice was gavaged for 3 consecutive days from day 19 post-infection with either bark extract or dimethyl sulphoxide (5%) as vehicle control. Oral administration of pine bark extract did not have an impact on any of the measured parasitological parameter. It did, however, have a positive impact on the performance of infected, slow-responder mice, through an increase in body weight (BW) and carcase weight and reduced feed intake by BW ratio. Importantly, bark extract administration had a negative impact on the fast responders, by reducing their ability to mediate the impact of parasitism through reducing their performance and tolerance. The results indicate that the impact of PSMs on parasitized hosts is affected by host's genetic susceptibility, with susceptible hosts benefiting more from bark extract administration compared to resistant ones.

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Abstract

To evaluate the environmental impact across multiple dairy farms cost-effectively, the methodological frame- work for environmental assessments may be redefined. This article aims to assess the ability of various statistical tools to predict impact assessment made from a Life Cyle Assessment (LCA). The different models predicted estimates of Greenhouse Gas (GHG) emissions, Energy (E) and Nitrogen (N) intensity. The functional unit in the study was defined as 2.78 MJMM human-edible energy from milk and meat. This amount is equivalent to the edible energy in one kg of energy-corrected milk but includes energy from milk and meat. The GHG emissions (GWP100) were calculated as kg CO2-eq per number of FU delivered, E intensity as fossil and renewable energy used divided by number of FU delivered, and N intensity as kg N imported and produced divided by kg N delivered in milk or meat (kg N/kg N). These predictions were based on 24 independent variables describing farm characteristics, management, use of external inputs, and dairy herd characteristics. All models were able to moderately estimate the results from the LCA calculations. However, their precision was low. Artificial Neural Network (ANN) was best for predicting GHG emissions on the test dataset, (RMSE = 0.50, R2 = 0.86), followed by Multiple Linear Regression (MLR) (RMSE = 0.68, R2 = 0.74). For E intensity, the Supported Vector Machine (SVM) model was performing best, (RMSE = 0.68, R2 = 0.73), followed by ANN (RMSE = 0.55, R2 = 0.71,) and Gradient Boosting Machine (GBM) (RMSE = 0.55, R2 = 0.71). For N intensity predictions the Multiple Linear Regression (MLR) (RMSE = 0.36, R2 = 0.89) and Lasso regression (RMSE = 0.36, R2 = 0.88), followed by the ANN (RMSE = 0.41, R2 = 0.86,). In this study, machine learning provided some benefits in prediction of GHG emission, over simpler models like Multiple Linear Regressions with backward selection. This benefit was limited for N and E intensity. The precision of predictions improved most when including the variables “fertiliser import nitrogen” (kg N/ha) and “proportion of milking cows” (number of dairy cows/number of all cattle) for predicting GHG emission across the different models. The inclusion of “fertiliser import nitrogen” was also important across the different models and prediction of E and N intensity.

2024

Abstract

This study investigates cow behaviour when visiting two GreenFeed Emission Monitoring (GEM) units within a Part-Time Grazing (PTG) system. Two separate PTG systems were assessed in Sweden and Norway, involving Nordic Red and Norwegian Red dairy cows, respectively. In Sweden, 24 cows were allocated to treatments with restricted access to pasture, either daytime or nighttime grazing. Meanwhile, the Norwegian PTG involved 33 cows with free pasture access, categorized by varying training levels (Partially or Fully). In both PTG systems, cows were exposed to GEM units positioned indoors (Indoor) and in the grazing pastures (Pasture), with individual visitations recorded. Significant variations in visitation patterns were observed. In the restricted access PTG, Nighttime grazing access cows exhibited reduced visits to the Indoor GEM unit but increased visits to the Pasture GEM unit compared to Daytime grazing. Conversely, within the free access PTG, fully trained cows demonstrated elevated visits to the pasture GEM unit and total visits compared to their partially trained counterparts. These findings highlight the influence of temporal conditions and training levels on cow-visiting behaviour within PTG systems.

Abstract

Presentation of preliminary findings from a feed trial conducted winter 2024, where the effect of feeding lactating dairy cows a 100% ensiled grass pulp diet was measured on production parameters, GHG-emissions, behaviour and metabolic markers, compared to regular whole plant silage from the same ley and harvest dates