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
No abstract has been registered
Abstract
An annual sheep production system in Norway incorporates grazing natural pastures for five months. Yet no measurements of enteric methane emissions from grazing sheep have been performed under Norwegian conditions. A pilot study was conducted with 12 Norwegian White ewes to test the feasibility of using the sulphur hexafluoride (SF6) tracer technique under Norwegian conditions. The ewes were split onto one of two pastures, mixed grass (Bromus inermis dominated, Poa pratensis, Festuca pratensis) or white clover (Trifolium repens). After five days adaptation to pastures, breathe samples were collected into evacuated one L PVC canisters over three consecutive days where capillary tubes (0.38 to 0.42 mL/min initial flow) restricted flow. Gas samples were analysed by gas chromatography. Feed intakes were not recorded. Average live weights were 64 kg and 66 kg for ewes on grass and clover pastures, respectively. Methane emissions were 23.9 g/d from sheep on mixed grass and 28.2 g/d for sheep on white clover. Methane emissions were not correlated (p=0.33) to ewe live weight. One explanation for the 15% difference in methane emission could be differences in feed intake. The few days of sample collection could also explain some of the observed difference since the technique is recommended to be used over five days to reduce errors in observations. This pilot study shows that using the SF6-technique is a feasible method for future research. More experiments measuring enteric methane emission over a longer period from grazing sheep and cattle under Norwegian conditions are planned for the future.
Abstract
The aim of this study was to investigate the use and capacity of electronic feed stations (EFS) on commercial sheep farms. The study was conducted on four commercial farms and the numbers of pregnant ewes per EFS were 36, 70, 72 and 80, respectively. Each farm was visited once and behavioural observations were carried out. In addition the date and time for both entering and leaving the EFS and the amount of concentrates dispensed at each visit for extracted. The vast majority of the ewes used the EFS regularly. The number of rewarded visits per ewe per day varied from 3.2 to 5.9, whereas the number of unrewarded visits ranged from 6.0 to 21.5 per ewe per day. We conclude that feeding concentrates to groups of pregnant ewes in EFS function satisfactory, but the design of the entrance and exit gate still have to be improved considerably.
Abstract
Horses use human-made shelters actively during inclement weather, but the costs of building shelters may be high and owners use blankets or rugs on horses instead. The aim of the study was to investigate how wearing a blanket might affect the shelter seeking behaviour of horses under coastal arctic winter conditions. Could blankets make shelters redundant? During different winter weather conditions, seventeen horses had a full-neck blanket of their size put on and were released in a test paddock. There, horses were given free choice between staying outdoors, going into a heated shelter compartment or into a non-heated shelter compartment. An observer scored horse’s location and behaviour using instantaneous sampling every minute for 1 h. Each horse was tested 2–12 days but only once per day. Detailed weather data (precipitation, wind and temperature) were continuously recorded by a weather station at the site. In general, horses with blankets still used the shelter and were observed inside in (mean per horse) 20.6% of total observations. Horses spent more time inside shelters on days with rain and wind (39.7% of tot obs) compared to on days with wind only (11.8% of tot obs, P = 0.05). Small coldblood horses were more active, spending more time in movement than large coldblood and large warmblood horses (P = 0.01). In conclusion, wearing blankets reduced the impact of inclement weather, but did not make the shelter redundant for horses, under Nordic winter conditions.
Abstract
Nitrous oxide (N2O) emissions from cultivated soils correlate positively with the amount of N-fertilizer applied, but a large proportion of the annual N2O emission occurs outside the cropping season, potentially blurring this correlation. We measured the effect of split-N application (total N addition varying from 0 to 220 kg N ha−1) on N2O emissions in a spring wheat plot trial in SE Norway from the time of split-N application until harvest, and during the following winter and spring thaw period. N2O emissions were largest in the two highest N-levels, whereas yield-scaled emission (N2O intensity) was highest in the 0 N treatment. Nitrogen yield increased by 23% when adding 80 kg N ha−1 compared to adding 40 kg N ha−1 as split application, while corresponding N2O emissions were reduced by 16%. No differences in measured emissions between the N-fertilization levels were observed during the winter period or during spring thaw. Measurements of soil air composition below the snow pack revealed that N2O production continued throughout winter as the concentration in the soil air increased from 0.37 to 30.0 µL L−1 N2O over the 3 months period with continuous snow cover. However, only 7–28% of the N2O emitted during spring thaw could be ascribed to accumulated N2O, indicating de novo production of N2O in the thawing soil. The direct effect of split-N fertilizer rate on N2O emissions in sub-boreal cereal cropping was limited to the first 15–21 days after N-addition.
Authors
Gillian Butler Sokratis Stergiadis Eleni Chatzidimitriou Enrica Franceschin Hannah R. Davis Carlo Leifert Håvard SteinshamnAbstract
Dairy products are often considered challenging for health due to their saturated fatty acid content, yet they also provide beneficial nutrients, some unique to ruminants. The degree of fat saturation is influenced by cows’ diets; grazing pasture enhances unsaturated fatty acids in milk compared with conserved forages. These benefits can be partially mimicked by feeding oilseeds and here we consider the impact on milk composition in a 2 × 2 trial, feeding rapeseed to both conventional and organic cows, finding very differing lipid metabolism in the 4 experimental groups. For milk fat, benefits of organic rather than conventional management (+39% PUFA, +24% long chain omega-3 and +12% conjugated linoleic acid (CLA)) appear complementary to those from feeding rape (+43% MUFA, +10% PUFA, +40% CLA), combining to produce milk 16% lower SFA and higher in MUFA (43%), PUFA (55%) and CLA (59%). Organic and rape feeding provide less omega-3 PUFA than the conventional and control diets, yet contrary to expectations, together they almost doubled (+94%) the omega-3 concentration in milk, implying a 3.8 fold increase in net transfer from diet into milk. Organic and rape feeding also gave lower trace-elements and antioxidants in milk. Greater understanding of these phenomena might enhance the sustainability of dairying.
Abstract
Two short-term grazing experiments were conducted with Norwegian Red cows. In Exp 1, 24 cows were randomly assigned to one of the following three pasture allocation methods (PAM): weekly pasture allowance (7RG), grazing 1/7 of 7RG each day (1SG), or grazing as 1SG but had access to grazed part of the paddock within one week (1FG). In Exp 2, 7RG was shortened to 5 days (5RG). We hypothesized that PAM will affect sward quality, quantity, intake and production differently. Pasture chemical composition changed with advancing grazing days but were not different between treatments. Pasture intake, milk yield, and methane emission were not affected by PAM. In Exp 1, 7RG cows spent less time on grazing, whereas in Exp 2, 1FG cows spent longer on grazing than others. Patterns observed in sward quality, and behavioural and physiological adaptations of cows to short-term changes in nutrient supply may explain the observed effects.
Authors
Håvard SteinshamnAbstract
No abstract has been registered
Authors
A Schmitt I Pertot V Verrastro Jakob Magid B Moeskops K Möller Spiridoula Athanasiadou C Experton Håvard Steinshamn F Leiber Veronika Maurer EK Bunemann J Herforth-Rahme Lucius TammAbstract
No abstract has been registered