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.
2008
Sammendrag
A 2 x 2 factorial continuous experiment was conducted with 28 Norwegian Red dairy cows in early lactation to compare milk content of phytoestrogens when feeding ad libitum white clover (WCS) or red clover (RCS) grass silages prepared from the second and third cut without and with 10 kg/d supplementation of a standard concentrate. The cows were offered either RCS or WCS for 88 d (period 1) and thereafter a mixed red clover-white clover-grass silage for 48 d (period 2). Total dry matter intake and milk yield were not affected by forage type but increased with concentrate supplementation. Intake of isoflavones was several times greater in RCS than in WCS, whereas intake of lignans was greater in WCS. Concentrate supplementation reduced the intake of most phytoestrogens. Compared with WCS, RCS diets yielded milk with a greater content of flavonoids, whereas milk from WCS diets had greater contents of the mammalian lignans enterodiol and enterolactone. The content of the isoflavan equol was particularly high in RCS diets. There was no apparent carryover effect of clover type on milk phytoestrogen content because there was no difference in content between the silage treatments 3 wk after the cows were transferred to the same silage diet (period 2). Concentrate supplementation reduced the milk contents of the flavonoids equol, biochanin A, and daidzein and increased the content of mammalian lignans. The effects of silage type and concentrate supplementation on milk contents of the individual phytoestrogens were related to the intake of the compound or its precursor, except for the effect of concentrate on mammalian lignans, for which the intake of the known precursors was also reduced. Overall, this study shows that feeding cows with silage containing red clover increases the milk content of flavonoids at both low and high concentrate supplementation levels, and decreases the content of nonflavonoids such as mammalian lignans, when compared with silage containing white clover. The increased content of phytoestrogens in milk may be important when the health benefits of milk are studied.
Sammendrag
Dikalvproduktion på skogs- och fjällbete kan ge lika stor tillväxt och slaktvikt som motsvaransde produktion på gödslat bete nära gården. Båda betestyperna gav hög slaktvikt och köttkvalitet. Fem gårdar i Lillehammerregionen i Norge deltog i studien. [Diekalvproduksjon på utmarksbeite kan gi like stor tilvekst og slaktevekt som tilsvarende produksjon på innmarksbeite. Begge beitetypene gav meget god kjøttkvalitet, med kun små forskjeller mellom kjøtt produsert på inn- og utmark. Prosjektet er gjennomført av Nortura og Bioforsk med besetninger av forskjellige storferaser fra Lillehammer, Gausdal, Øyer og Ås. ]
Forfattere
Håvard Steinshamn Mats Høglind Øystein Havrevoll Kristin Saarem Inger Helene Lombnæs Asgeir SvendsenSammendrag
Målet med arbeidet var å granske effekten av fjellbeite på vekst og kjøttkvalitet hos ammekalvar. Ammekalvar med sine mødre gikk anten på innmarksbeite (I) ved garden eller på fjell-/skogsbeite (F) på fire (2006) og fem (2007) gardar. F-beita var ulike vegtasjonstypar frå opne, grasdominerte områder til skog med gras, urter og busker. Alle kalvane vart slakta rett etter beitesesongen då dei var i gjennomsnitt 203 (2006) og 193 (2007) dagar gamle. I gjennomsnitt var det ingen effekt av beitetype på produkskjon bortsett frå at slakta frå F vart klassifisert som feitare enn dei som kom frå I. I 2006 var den daglege tilveksten og slaktevekta signifikant høgare hos kalvane i frå I, medan det motsatte resultatet vart funne i 2007. Kjemiske analysar er ferdig berre for 2006. Totalt feittinnhald i ytrefileten var signifikant høgare hos kalvane på M (12 vs 14 g/kg, P < 0.05). Det var elles ingen skilnad mellom forsøksledda i kjøttkvalitet.
Forfattere
Håvard SteinshamnSammendrag
Gjennomganmg i utfordringane i økologisk mjølkeprodukjson
Forfattere
Håvard SteinshamnSammendrag
Samanstilling av kløveren sin viktige rolle i økologisk produksjon
Forfattere
Håvard SteinshamnSammendrag
Sammanetilling av egne og andre sine forsking på sammenheng mellom driftsopplegg og mjøkekvalitet
Sammendrag
Kvitkløver egnar seg godt i slåtteng også i Noreg. Samanlikna med raudkløvergraseng, gav kvitkløvergraseng like stor avling og same mjølkeproduksjon. Raudkløver i surfôret gav høgare innhald av fleirumetta feitt og mykje høgare innhald av planteøstrogen i mjølka enn kvitkløver.
Forfattere
Håvard SteinshamnSammendrag
Grassland legumes are essential in organic ruminant livestock production due to their ability to fix atmospheric nitrogen (N), providing high yields of high feeding value without N fertilization. White clover (Trifolium repens L.) and red clover (Trifolium pratense L.) are the most important legumes of temperate grasslands with white clover as the most widely used. New research has reviled new properties of red clover that may affect animal performance and product quality significantly. Red clover containing diets have increased the production of milk and meat (compared with grasses) and the content of beneficial fatty acids in milk and meat (compared with grasses and other legumes), improved the efficiency of feed N utilization (compared with Medicago sativa L.), and increased the milk content of isoflavones (compared with grass and white clover). Red clover contains high levels of the enzyme polyphenol oxidase that might reduce the extent of lipolysis and proteolysis. The paper presents a review on resent results from own and others" research on the use of red clover in the diet of ruminants and the likely mechanisms by which red clover affects production and product quality
Sammendrag
Red (RC) or white (WC) clover were grown in mixture with grasses, ensiled and offered to dairy cows in early lactation over two successive years (48 cows per year) to compare grassland yield, feed intake, milk production and milk quality. The crops were ensiled in round bales and proportional mixtures of the second and third cut prepared each year were used to ensure that the silage treatments were representative of the crop. In addition to silage type, concentrate supplementation, without and with (10 kg/day), was included as a factor in a 2 X 2 factorial, continuous experiment. Total dry matter (DM) yield, silage chemical composition and total DM intake was hardly affected by silage type. There was no effect of silage type on milk yield and milk constituents either, except for higher milk protein content (P < 0.05) on WC and higher milk fat content of C18:3n-3 (P < 0.001), C18:2n-6 (P < 0.05) fatty acids (FAs) and sum of polyunsaturated FA (P < 0.001) and lower n-6/n-3 FA ratio (P < 0.01) on RC. Concentrate supplementation increased total DM, N and net energy intakes (P < 0.001), milk yield (P < 0.001), milk fat (P < 0.01) and protein (P < 0.001) content, decreased the milk urea content (P < 0.001), and increased the milk fat content of short- and medium-chained FAs (< C16, P < 0.001), C18:0 (P < 0.01) and C18:2n-6 (P < 0.001), decreased the content of C16:0 (P < 0.05), C18:1t11 (P < 0.001) and C 18:3n-3 (P < 0.001), and increased then 6/n-3 FA ratio (P < 0.001). The effect of concentrate supplementation was not affected by silage type, except for milk protein content where the positive effect of supplementation was stronger on WC than on RC diets (P < 0.05). This study illustrates that the white- and red clover-grass mixtures investigated were widely similar with regard to their effects on grassland yield, silage intake and milk production and milk constituents, except for a higher milk fat content of C18:3n-3 and C18:2n-6 and lower n-6/n-3 FA ratio on red clover diets. Our findings also show that N conversion efficiency from feed to milk on pure forage diets is more sensitive to changes in dietary protein intake than silage diets containing cereal based concentrates. (C) 2008 Elsevier B.V. All rights reserved.
Forfattere
Martha Ebbesvik Sissel Hansen Anne Kjersti Bakken Turid Strøm Espen Govasmark Håvard SteinshamnSammendrag
Innholdet av råprotein i en stor del av graset fra førsteslåtten på økologiske ku- og sauegårder var lavt. Innholdet i andreslåtten var høyere. Kløverandelen i engavlinga forklarte en stor andel av variasjonen i proteininnholdet.