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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.

2009

Sammendrag

Utegangarsauen av gamal norrøn rase (Ovis brachyura) er nøysam og tilpassa heilårsbeiting i kystlynghei. Sauen beiter allsidig. Variasjonen i fòrtilgang gjennom året avteiknar seg i produksjon og levandevekt hjå utegangarsauen.

Sammendrag

Etter 1950 har det skjedd store endringar i landbruket, og mange tradisjonelle og ekstensive driftsformer har fått mindre omfang eller gått ut av bruk. Når beitebruken i område med kystlynghei fell bort, opphøyrer også sviing og andre skjøtselstiltak. I Noreg har ein klart å ta vare på ein gammal husdyrrase, norrøn stuttrompa sau (Ovis aries), i dei ytre kyststroka. Sauen er nøysam og godt tilpassa heilårsbeiting. Han er korthala, lettbygd og høgføtt, og finst i fleire fargevariantar. Denne sauen dominerte sauehaldet i Noreg til siste halvdel på 1800-talet.

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Sammendrag

Diversity of clovers in grass-clover swards may contribute to greater herbage yields and stability of yield. This possible effect was evaluated in an experiment carried out over three harvest years at two contrasting sites, differing in precipitation and soil composition, using mixed swards containing either one, two or three clover species sown together with timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis L.). The clover species were red clover (Trifolium pratense L.), white clover (Trifolium repens L.) and alsike clover (Trifolium hybridum L.) sown in various proportions in a total of ten treatments. All swards were fertilized with nitrogen with amounts that increased from year to year, and three harvests were taken in three consecutive years. There was a significant interaction between site and species mixture on total dry matter (DM) yields (range 27-32 tonnes ha-1) and DM yields of clovers (range 5-15 tonnes ha-1); red clover as a single species or in a mixture was superior at the dry site while multi-clover species mixtures were superior at the wet site. Alsike clover was the least productive species of clover. Stability of yield of clovers was generally higher by including white and red clover in the seed mixture but total DM yield was not.

Sammendrag

In Norway, the goal of 15% organic food production within 2015 is too ambitious if the current growth rate of organic farmland is continued. Hence, a study of bottlenecks within organic farming systems in Northern Norway, and farmer"s preconditions to convert was conducted in spring 2007. A questionnaire was sent to certified and former certified organic farmers, and a control group of conventional farmers. For organic farmers the most important bottlenecks were public regulations and organic price premiums. Conventional farmers feared yield decrease, restricted forage availability and extra work. In 2008, interviews with selected farmers and officials in local municipalities were conducted to explore the reasons for large differences between certified organic farmland.

Sammendrag

Nitrogen (N) er kvantitativt det viktigste næringsstoff for vekst og reproduksjon. Nitrogenfikserende planter er avgjørende for å forsyne andre planter med N og for at fôr skal bli en bedre proteinkilde. Hvilke faktorer påvirker potensialet for biologisk nitrogenfiksering og hvordan overlever kløveren den lange nordnorske vinteren?

Sammendrag

Nitrogen (N) er kvantitativt det viktigste næringsstoff for vekst og reproduksjon. Nitrogenfikserende planter er avgjørende for å forsyne andre planter med N og for at fôr skal bli en bedre proteinkilde. Hvilke faktorer påvirker potensialet for biologisk nitrogenfiksering og hvordan overlever kløveren den lange nordnorske vinteren?

Sammendrag

Omlagt areal i 2008 (inkludert areal i karens) varierte fra 0 % til 24 % mellom de ulike kommunene i Nordland fylke. Derfor ble det undersøkt hvilke faktorer som ligger bak og som kan bidra til å forklare disse ulikhetene. Det ble valgt ut kommuner med lite (< 2.5 %) eller mye (> 10 %) omlagt økologisk areal og gjennomført telefonintervju med to til tre informanter fra hver kommune. De viktigste sammenhenger synes å være mellom omlagt areal og kommunal innsats; og øko-miljø i kommunen (smitteeffekt/naboeffekt); og holdning/interesse for økologisk landbruk blant bønder, lokale organisasjoner og myndigheter; og tilgang til ledig areal i kommunen.

Sammendrag

The general aim of this thesis was to gain more knowledge on how the sensory profile and fatty acid composition of meat from lambs were affected when lambs were finished on concentrate and roughage or different types of pastures. The different types of pastures were mountain pastures, cultivated pastures, ryegrass pastures and semi-natural pastures. The effect of gender on meat quality was examined as well. To evaluate the effects of these factors, three studies were performed.In the first study (Paper I) the sensory profile and fatty acid composition in meat from lambs slaughtered directly from unimproved mountain pastures was compared with meat from lambs raised on unimproved mountain pastures and fattened on biodiverse cultivated pastures for 26, 39 and 42 days, respectively, before slaughter. This experiment was conducted at two different locations in Norway in 2006 and 2007, with a total of 124 Norwegian White Sheep (NWS) lambs. Loin samples of M. Longissimus dorsi from lambs above a live body weight of 40 kg were selected and analysed for sensory attributes, and fatty acid composition was determined in the subcutaneous fat over the Longissimus dorsi. Significant differences were found in the sensory attributes of hardness, tenderness, fattiness, metallic and rancid flavour, and in the polyunsaturated fatty acid content between the two treatments.The effects of the different production systems on sensory attributes and fatty acid composition were examined in the second study (Paper II). 150 NWS lambs grazed on the same semi-natural lowland pasture with their dams for three months or more. The effect of pre-slaughter fattening on meat quality was compared using a control group of lambs slaughtered directly from the pasture. Four pre-slaughter treatments were established: weaning and indoor-feeding on concentrate and grass silage for either 44 or 24 days before slaughtering (Conc44, Conc24), and grazing on ryegrass pasture for the same periods (Rye44, Rye24). Loin samples of M. Longissimus dorsi including the subcutaneous fat over the muscle from 15 carcasses from each treatment were analysed for sensory attributes and fatty acid composition. A lower intensity of acid taste was observed in meat from lambs in treatment Conc44 compared with meat from lambs in the control treatment. A higher content of the fatty acids C16:0, C18:1n-9 and C18:2n-6 and the n-6/n-3 ratios was related to meat from lambs fed concentrate, while a higher content of the fatty acids C18:0, C18:1t-11 and C18:3n-3 was found in meat from grazing lambs. In the third study (Paper III), the effect of gender and feeding on the fatty acid composition and sensory profile of meat from NWS lambs was investigated. Lambs from the 2006 treatment in Northern Norway in Study I were used in the first experiment including 22 female and 22 male lambs. In addition, all lambs from Study II, including 46 female and 29 male lambs, were used in the second experiment. Loin samples of M. Longissimus dorsi were analyzed for sensory profile and fatty acid composition. All lambs were slaughtered in September. There were no significant differences in sensory profile between lambs in experiment 1, while in experiment 2, meat from male lambs had higher scores for cloying and rancid flavour and lower scores for sour and sweet taste compared to meat from female lambs. The main conclusions from the present study are that finishing lambs on cultivated pastures can alter the sensory profile and fatty acid composition acquired on mountain pastures to a small degree. Finishing lambs indoors on concentrate and roughage can also alter the fatty acid composition in the meat compared to meat from lambs that graze on semi-natural pastures during the summer. The differences in sensory profile between genders in favour of the meat from female lambs indicate that females may be prioritised over males and off-season fresh meat should preferably be produced from female lambs. Furthermore, male lambs should be given the optimum conditions to be prepared for slaughter early in the season thereby reducing the risk of quality problems. Meat from lambs that is not ready for slaughter when gathered from natural and semi-natural pastures in the autumn should be marketed separately.