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.
2006
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Three continuous production experiments and three short term cross over experiments were carried out in Northern Norway to investigate different feeding strategies for dairy cows in organic farming. This paper focuses on the effects on sensoric milk quality. Half of the 32 Norwegian red dairy cows in the production experiments were fed 40% (HC) concentrates (on energy basis per year) and the other half 10% (LC). Twelve cows (HC) participated in the short term cross over experiments. The experimental factors in the continuous production experiments were barley preservation method (P1), grass silage maturity (P2) and type of protein supplement (P3), and in the short term cross over experiments barley preservation method (C1), type of protein supplement (C2) and time for fishmeal feeding (C3). In all experiments the cows were offered grass silage ad libitum, restricted amounts of cereals and protein feeds, and mineral and vitamin supplements. The sensoric quality of milk was in general high. In the production experiments, milk from cows in HC had slightly higher quality than from cows in LC (significant in P2, p = 0.04). Neither the preservation method of barley (dried or ensiled with molasses), maturity of grass silage or type of protein supplement (fishmeal or peameal) influenced the sensoric milk quality significantly. Also in the cross over experiments no effect of the studied factors was found in milk flavour and odour. Early harvested grass silage gave significantly lower FFA contents than grass silage cut at normal time (P2) and FM gave significantly lower FFA concentrations than peameal (P3). These results indicate that organic farmers with different feeding regimes can produce milk of first class sensoric quality. Also the content of FFA has been low in all experiments (except C1). However, feeding regimes containing low levels of concentrates may reduce milk taste slightly.
Forfattere
Steffen Adler Åshild T. RandbySammendrag
Three continuous production experiments and three short term cross over experiments were carried out in Northern Norway to investigate different feeding strategies for dairy cows in organic farming. This paper focuses on the effects on sensoric milk quality. Half of the 32 Norwegian red dairy cows in the production experiments were fed 40% (HC) concentrates (on energy basis per year) and the other half 10% (LC). Twelve cows (HC) participated in the short term cross over experiments. The experimental factors in the continuous production experiments were barley preservation method (P1), grass silage maturity (P2) and type of protein supplement (P3), and in the short term cross over experiments barley preservation method (C1), type of protein supplement (C2) and time for fishmeal feeding (C3). In all experiments the cows were offered grass silage ad libitum, restricted amounts of cereals and protein feeds, and mineral and vitamin supplements. The sensoric quality of milk was in general high. In the production experiments, milk from cows in HC had slightly higher quality than from cows in LC (significant in P2, p = 0.04). Neither the preservation method of barley (dried or ensiled with molasses), maturity of grass silage or type of protein supplement (fishmeal or peameal) influenced the sensoric milk quality significantly. Also in the cross over experiments no effect of the studied factors was found in milk flavour and odour. Early harvested grass silage gave significantly lower FFA contents than grass silage cut at normal time (P2) and FM gave significantly lower FFA concentrations than peameal (P3). These results indicate that organic farmers with different feeding regimes can produce milk of first class sensoric quality. Also the content of FFA has been low in all experiments (except C1). However, feeding regimes containing low levels of concentrates may reduce milk taste slightly.
Sammendrag
Three multiparous cannulated dairy cows were used to test the effect of including 0, 23 % and 46 % red clover (RC) on dry matter (DM) basis in timothy (T) silage on nitrogen (N) intake, utilization and excretion. The cows were offered a fixed ration; 13 kg silage and 7 kg concentrate DM. The N intake and urine N excretion increased with increasing silage clover proportion. Milk yield was higher in the clover containing silages than in the pure grass silage, probably due to higher organic matter digestibility in RC containing silages. The efficiency in converting feed N into milk N, however, was higher in cows fed the timothy silage than in cows offered grass/clover silages. The efficiency in microbial protein synthesis in the rumen and the proportion of microbial N of the total N flow to duodenum was higher on the T diet than on the RC containing diets. However, the clover diets gave a slightly higher proportion of bypass N originating from the feed. So, the total flow of N to duodenum was the same for all three diets. In conclusion, increased proportion of RC in T silage did not improve the N utilization.
Forfattere
Svein Øivind Solberg Steinar DraglandSammendrag
Varius plastic mulch, fiber mulch and paper mulch were examined in four perennial herb crops in a field experiment during a three-year period in Norway. Over-wintering, total yield, herbs nutrient content, soil temperatur, and soil nitrogen were examined.
Sammendrag
Ærfugl er en karakteristisk og relatrivt vanlig art langs kysten av Skandinavia. Den har hatt en viktig økonomisk betydning for folk langs kysten gjennom flere hundrede år som en klide til mat og dun, en utnyttelse som i dag har opphørt. På grunn av en kontinuerlig nedgang i ærfuglpopulasjonen på øya Tautra i Trondheimsfjorden siden slutten av 1970 åra har flere ulike bevaringstiltak vært satt i verk, uten at en til nå har lykkest med å snu utviklingen. Denne artikkelen presenterer forsøkene på å bevare en minkende ærfuglpopulasjon som en case-studie på utfordringene knyttet til bevaring av kulturlandskap, og illustrerer de komplekse forbindelsene mellom menneskelig bruk av biologiske ressurser og skaping av habitat i det førindustrielle jordbruket. På Tautra har jordbrukets utnytting av utmark og utmarksressursene tilført landskapet habitat som er viktige for ærfuglbestanden. Artikkelen synliggjør hvorledes forvaltingsregimet har å fokusert på enkelttiltak ensidig rettet mot enkeltarter og unnlatt å oppdage og inkorporere flere dimensjoner med betydning for forming og vedlikehold av habitat for arten. For å lykkes med å bevare biologiske verdier og forstå den økologiske dynamikken mellom habitat og populasjoner i kulturlandskap må de historiske aspektene knytta til resursutnyttingen involveres. Siden biodiversitet og økologisk dynamikk i et habitat er relatert til andre habitat, er det nødvendig å inkludere mosaikken mellom forskjellige habitat i den langsiktige forvaltingen av slike områder.
Foredrag – The fate of glyphosate in Norwegian soils
Marit Almvik, Ole Martin Eklo, Randi Bolli, ...
Forfattere
Marit Almvik Ole Martin Eklo Randi Bolli Marianne Stenrød Jens Kværner Tore Sveistrup Espen HauglandSammendrag
Det er ikke registrert sammendrag
Sammendrag
Presentasjon av en analyse av hydrologien i to nedbørsfelter i Estland og Norge. Analysen aer basert på flashiness indeks. Det er store forskjeller i flashiness indeks mellom Norske og Estiske felt. Analysen kan være et bidrag i forklaringen av forskjeller i næringsstofftap og erosjon. Samtidig kan det gi et bidrag i utformingen av prøvetakingsrutiner.
Sammendrag
An analysis of runoff measurements can reveal a great deal about the hydrological character of a catchment. There are different ways to carry out such a hydrological characterization. In this paper, characterisation of the hydrological behaviour of catchments is carried out by describing the flashiness of the runoff. Flashiness in this case is meant to express the variation in runoff over short periods. A modified flashiness index has been calculated for small agricultural catchments in Estonia and Norway respectively, based on hourly recorded discharges and a comparison has been made with results obtained from a flashiness index, which is based on average daily discharge values. The comparison revealed large differences between the two index values for the Norwegian catchments, indicating large variations in discharge values over short periods or a "flashy" nature in runoff. Only small differences were found for the Estonian catchments. Large differences were found when comparing the Norwegian and Estonian catchments. Although the flashiness index does not a-priori give information about the flow processes, it might be helpful in explaining differences in nutrient and soil losses between catchments.
Forfattere
Hege Hvattum Divon Carmit Ziv Olga Davydov Oded Yarden Robert Fluhr Hege DivonSammendrag
Fusarium oxysporum is a soil-borne pathogen that infects plants through the roots and uses the vascular system for host ingress. Specialized for this route of infection, F. oxysporum is able to adapt to the scarce nutrient environment in the xylem vessels. Here we report the cloning of the F. oxysporum global nitrogen regulator, Fnr1, and show that it is one of the determinants for fungal fitness during in planta growth. The Fnr1 gene has a single conserved GATA-type zinc finger domain and is 96% and 48% identical to AREA-GF from Gibberella fujikuroi, and NIT2 from Neurospora crassa, respectively. Fnr1 cDNA, expressed under a constitutive promoter, was able to complement functionally an N. crassa nit-2(RIP) mutant, restoring the ability of the mutant to utilize nitrate. Fnr1 disruption mutants showed high tolerance to chlorate and reduced ability to utilize several secondary nitrogen sources such as amino acids, hypoxanthine and uric acid, whereas growth on favourable nitrogen sources was not affected. Fnr1 disruption also abolished in vitro expression of nutrition genes, normally induced during the early phase of infection. In an infection assay on tomato seedlings, infection rate of disruption mutants was significantly delayed in comparison with the parental strain. Our results indicate that FNR1 mediates adaptation to nitrogen-poor conditions in planta through the regulation of secondary nitrogen acquisition, and as such acts as a determinant for fungal fitness during infection.