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.
2011
Forfattere
May Bente Brurberg Abdelhameed Elameen Vinh Hong Le Ragnhild Nærstad Arne Hermansen Ari Lehtinen Asko Hannukkala Bent Nielsen Jens Hansen Björn Andersson Jonoathan YuenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
I løpet av de siste hundre åra har skogarealet økt med over 50 prosent. Det forventes å øke betydelig i årene framover, spesielt i kyst- og fjellregionene, noe som får store konsekvenser for deler av turistnæringen som lever av utsikten til vårt fantastiske natur- og kulturlandskap.
Forfattere
Abdelhameed Elameen Arild Larsen Sonja Klemsdal Siri Fjellheim Leif Sundheim Susan Msolla Esther Masumba Odd Arne RognliSammendrag
Det er ikke registrert sammendrag
Forfattere
Arne Fjellberg Arne FjellbergSammendrag
Spretthaler (Collemboler) er en gruppe med små dyr som lever i vegetasjonen, i strølaget og nedover i selve jorda til ca 15 cm dyp. De er viktige omdannere og nedbrytere av dødt plantemateriale og bidrar vesentlig til sirkulering av næringsstoffer. Navnet kommer av en «hoppegaffel» (furca) på bakkroppen. Denne er vanligvis foldet inn under dyret, men når den løses ut, spretter dyret opp i lufta og langt bortover bakken. Spretthalene kan hoppe mer enn 50 ganger sin egen kroppslengde i ett hopp.
Sammendrag
On small dairy farms, high investment costs and lack of investment capital may delay the modernising of facilities. The aim of this study was to investigate the importance of economics of scale in building costs of barns compared to other sources of variation in costs. The study includes 44 farms with a mean herd size of 49.5 ± 15.1 cows, built between year 1999 and 2006 and with a mean total area in the barns of 896 ± 454 m2. Building cost data were obtained from farmers and merged with construction, mechanisation and layout data from the same barns. Construction costs decreased up to approximately 1250 m2 while mechanisation costs and total building costs decreased up to approximately 1000 m2. A further increase in building area had only limited effect on the building costs per m2. Models including explanatory variables showed that milking and service area was significantly more expensive than other areas. AMS-barns were all together not significantly more expensive than other barns, since the increased mechanisation cost is offset by a lower requirement for milking area. Farmers remodelling their barns were able to realise a modernised building for a certain herd size for a lower cost compared to a completely new building. The use of their own effort varied considerably between projects. In many cases, farmers would be able to find alternative income sources with a higher hourly rate than the value of their own effort suggested by the model.
Forfattere
Jack D´Arcy E. Dunaevskaya Richard Fitzgerald Jim W. Treasurer Oddvar Ottesen Julie Maguire Celine Rebours Nina Zhuravleva Åsbjørn KarlsenSammendrag
The use of wrasse (F. Labridae) as biological cleaner-fish in the control of salmon lice has been demonstrated in a number of studies and they are successfully used on a large scale, with over two million wrasse being caught and stocked annually, in commercial salmon farms in Norway. Increasingly, efforts are being made to produce commercial stocks of wrasse for use on farms and an EU Northern Periphery Project entitled "Ecofish" has been established to develop the technologies for spawning and rearing the most promising cleaner fish, ballan wrasse, in captivity with dedicated production hatcheries will be established in Ireland, Norway and Scotland. This project will also look into the management of ballan wrasse in salmon cages in order to achieve the effective removal of lice. As part of the Ecofish work programme, this study examined the embryonic development of Ballan wrasse using material from a series of spawnings in Ireland and Norway. The overall development from fertilization to hatch was monitored and recorded and a standardized series of developmental stages are assigned, from zygote through cleavage, blastulation, gastrulation, segmentation to hatching: each with specific morphological landmarks. This standardization and the synchronization of the developmental stages will facilitate future studies with the species as we may be better able to compare the development rate of different geographic stocks and under different environmental conditions. The developing embryo was also staged at three different incubation temperatures; 10.5oC, 12.9 oC, and 16.5 oC with 50% hatched occurring at 171, 121 ands 96 hours post fertilisation respectively.
Sammendrag
Abstract Due to difficulties in tracing engineered nanoparticles (ENPs) in complex media, there are few data on the exposure of soil biota to ENPs. This study used neutron activated cobalt (Co NPs) and silver (Ag NPs) nanoparticles, as well as soluble cobalt and silver salts, to assess the uptake, excretion and biodistribution in the earthworm Eisenia fetida. Concentrations of cobalt in worms after four weeks exposure reached 88% and 69% of the Co ions and Co NPs concentrations in food, respectively, while corresponding values for Ag ions and Ag NPs were 2.3% and 0.4%. Both Ag ions and Ag NPs in earthworms were excreted rapidly, while only 32% of the cobalt accumulated from Co ions and Co NPs were excreted within four months. High accumulation of cobalt was found in blood and in the digestive tract. Metal characterization in the exposure medium was assessed by sequential extraction and ultrafiltration. The Co NPs showed significant dissolution and release of ions, while Ag ions and particularly Ag NPs were more inert.
Forfattere
grete h m jørgensenSammendrag
Paddock size and enrichment - the effects on horse behavior Grete H.M. Jørgensen1 and Knut E. Bøe2 1Bioforsk Norwegian Institute for Agricultural and Environmental Research, 8860 Tjøtta 2Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, UMB, 1430 ås Corresponding author: +47 40 76 67 69 e-mail grete.jorgensen@bioforsk.no New regulations for horse keeping in 2005 suggested a paddock size of at least 300 m2 per horse and that every horse should have at least 2 hours turnout per day. Some of this time could however be replaced with forced exercise if the horse was kept in a box and not in a tie-stall. Whether this paddock size is large enough and how exercise affects horse behavior and activity during turnout has not been studied in detail. Horses are very motivated for social contact and several stereotypic behaviours like waving and pacing could be related to frustration and the wish for contact with conspecifics. Many commercial products for environmental enrichments are now available, both with the aim to reduce boredom and to keep horses occupied in harmless activities when kept individually. How horses use such "toys" is however scarcely studied. We performed several studies to investigate issues related to paddocks and turnout. Our results show that horses were more active in large paddocks (10 x 45m), spending less time standing and more time walking, exploring and eating grass from under the fence than in small (10 x 15m) and medium sized paddocks (10 x 30m). Horses in the large paddocks also travelled a longer distance than in the small and medium paddock size. When kept in individual paddocks, the dominating behaviours during turnout were standing (51.5% of tot obs) and eating grass from under the fence (27.1%). Horses that were exercised daily for 45 minutes in a walking pace became more passive, spending more time standing (52.9%) and less time walking (5.1%) during turnout, compared to when not exercised (standing: 44.4%; walking: 9.2%). When kept in groups the same horses spent only 5.3% of their time standing and 74.4% of their time eating grass from under the fence. This is probably an effect of social facilitation. Very few incidents of aggressive interactions were recorded when the horses were kept in social groups, but bouts of social grooming were observed. The items that were edible (straw, ball filled with concentrates, branches) received the most attention from the horses regardless of being kept individually or in groups. Straw and a ball filled with concentrates were the most popular items. Peat, a plastic ball and a cone were investigated less than 0.5% of total observations. A scratching pole was used (1.7 - 2.2% of tot obs), but due to horses using it in rather short intervals, it was difficult to catch all events with our recording methods. The ability to eat grass was more important for reducing passive standing than the access to items, both for horses kept individually (correlation between eating grass and passive standing R=-0.97; P
Forfattere
Snorre Stuen Lise Grøva Erik Georg Granquist Karin Sandstedt Ingrid Olesen Håvard SteinshamnSammendrag
A comparative study of clinical manifestations, haematological and serological responses after experimental infection with Anaplasma phagocytophilum in two Norwegian sheep breeds Background: It has been questioned if the old native Norwegian sheep breed, Old Norse Sheep (also called Norwegian Feral Sheep), normally distributed on coastal areas where ticks are abundant, is more protected against tick-borne infections than other Norwegian breeds due to a continuously high selection pressure on pasture. The aim of the present study was to test this hypothesis in an experimental infection study. Methods: Five-months-old lambs of two Norwegian sheep breeds, Norwegian White (NW) sheep and Old Norse (ON) sheep, were experimentally infected with a 16S rRNA genetic variant of Anaplasma phagocytophilum (similar to GenBank accession number M73220). The experiment was repeated for two subsequent years, 2008 and 2009, with the use of 16 lambs of each breed annually. Ten lambs of each breed were inoculated intravenously each year with 0.4 ml A. phagocytophilum-infected blood containing approximately 0.5x106 infected neutrophils/ml. Six lambs of each breed were used as uninfected controls. Half of the primary inoculated lambs in each breed were re-challenged with the same infectious dose at nine (2008) and twelve (2009) weeks after the first challenge. The clinical, haematological and serological responses to A. phagocytophilum infection were compared in the two sheep breeds. Results: The present study indicates a difference in fever response and infection rate between breeds of Norwegian sheep after experimental infection with A. phagocytophilum. Conclusion: Although clinical response seems to be less in ON-lambs compared to NWlambs, further studies including more animals are needed to evaluate if the ON-breed is more protected against tick-borne infections than other Norwegian breeds.