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.
2012
Authors
Margarita Novoa-Garrido Lise Aanensen Hans Jørgen S. Larsen Søren Krogh Jensen Håvard SteinshamnAbstract
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Authors
Margarita Novoa-Garrido Lise Aanensen Vibeke Lind Hans Jørgen S. Larsen Søren Krogh Jensen Espen Govasmark Håvard SteinshamnAbstract
No abstract has been registered
Authors
Steffen AdlerAbstract
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Authors
Annika Höjer Steffen Adler Kjell Martinsson Søren K. Jensen Håvard Steinshamn Erling Thuen Anne-Maj GustavssonAbstract
Two feeding experiments were performed to study the effects of silage botanical composition, regrowth interval and α-tocopherol supplementation on the fatty acid (FA) composition and α-tocopherol, β-carotene and retinol concentrations of milk. In Exp. 1, 24 Swedish Red dairy cows were fed two- or three-cut red clover–grass silages (R2 and R3, respectively) or two-cut birdsfoot trefoil–grass silage (B2). In Exp. 2, 16 Norwegian Red dairy cows were fed short-term ley silage with red clover (S3) or long-term ley silage with white clover (L3) in combination with the supplementation of RRR-α-tocopheryl acetate (1600 mg/day). The FA proportions in the milk and the recoveries of C18:2n-6 and C18:3n-3 were higher on the red clover diets R2 and S3 than on B2 and L3, respectively, and the n-6/n-3 FA ratio was also higher on the red clover diets. Shorter regrowth interval increased both the concentrations of FA in silage and the proportions of unsaturated FA in milk. Intakes of α-tocopherol, β-carotene and lutein were higher on B2 than on R2 due to higher silage intake on B2. However, the highest intake was seen on diet R3 due to the higher concentrations in the silage mixture. In Exp. 2, intakes of α-tocopherol, β-carotene and lutein were higher on L3. However, not all of these differences affected the milk, since the only significant differences related to silage diet in the two experiments were a higher milk α-tocopherol concentration on L3 than on S3 and a slightly lower β-carotene concentration on B2 than on R2. Supplementation with α-tocopherol increased milk α-tocopherol concentrations from 0.77 to 1.05 and from 1.07 to 1.24 mg/kg milk for S3 and L3, respectively, but did not affect milk FA composition. A higher concentration of antioxidants in the feed could be beneficial as a larger proportion of the animal's vitamin requirements would be met by the forage and the need for supplementation might decrease.
Authors
Annika Höjer Steffen Adler Stig Purup Hansen-Møller Jens Martinsson Kjell Håvard Steinshamn Anne-Maj GustavssonAbstract
Phytoestrogens are hormone-like substances in plants that can substantially influence human health (positively or negatively), and when fed to dairy cows are transferred to their milk. The aim of this study was to investigate effects of varying the botanical composition and regrowth interval of legume-grass silage on silage and phytoestrogen intake and milk phytoestrogen concentrations. In one experiment, 15 Swedish Red dairy cows were fed two- or three-cut red clover-grass silage (designated R2 and R3, respectively), or two-cut birdsfoot trefoil-grass silage (B2). In a second experiment, 16 Norwegian Red dairy cows were fed short-term ley silage with red clover (S3) or long-term ley silage with white clover (L3), and the effects of supplementation with α-tocopherol were also tested. There were high concentrations of formononetin and biochanin A in all silage mixtures with red clover (R2, R3, and S3). The milk concentration of equol was highest on diet R2 (1,494 μg/kg milk). Due to metabolism of biochanin A, genistein and prunetin, their concentrations in milk and the apparent recovery were low. Coumestrol was only detected in silage mixtures S3 and L3, and its milk concentration was low. Concentrations of secoisolariciresinol and matairesinol were higher in silage mixtures B2 and L3, those with legume species other than red clover and the highest grass proportions. B2 also resulted in higher enterolactone concentration than the other diets (226 μg/kg milk). Lengthening the regrowth interval increased the intake of secoisolariciresinol and decreased recovery of lignans. Feeding long-term ley silage resulted in higher lignan milk concentrations, but lower isoflavone milk concentrations than feeding short-term ley silage. The apparent recovery of all phytoestrogens except prunetin was highest on B2, indicating that condensed tannins (present in the birdsfoot trefoil) affect rumen metabolism. There was no effect of α-tocopherol supplementation on milk concentrations of any of the measured phytoestrogens. There were variations in milk concentrations of phytoestrogens, especially of equol, among cows, which could not be explained by variations in diet composition or phytoestrogen intake. The results show that milk phytoestrogen concentration is strongly influenced by silage botanical composition and management, but questions regarding phytoestrogen metabolism remain to be answered.
Authors
Laura Parducci Tina Jørgensen Mari Mette Tollefsrud Ellen Elverland Torbjørn Alm Sonia L. Fontana Keith D. Bennett James Haile Irina Matetovici Yoshihisa Suyama Mary E. Edwards Kenneth Andersen Morten Rasmussen Sanne Boessenkool Eric Coissac Christian Brochmann Pierre Taberlet Michael Houmark-Nielsen Nicolaj K. Larsen Ludovic Orlando M. Thomas P. Gilbert Kurt H. Kjær Inger Greve Alsos Eske WillerslevAbstract
No abstract has been registered
Abstract
In order to detect the efficiency of the nitrogen (N2) fixation in clover-grass leys in northern climate conditions, we studied how soil compaction affects growth and N2 -fixation of white clover (Trifolium repens L.) under contrasting growth conditions. A pot experiment was carried out under controlled climatic conditions in the phytotron at Holt (Tromsø). Sandy soil was compacted to two levels, 60% and 85% of the standard degree of compactness (SDC). Four seedlings of white clover plants or timothy (Phleum pratense L.) were carefully planted in each pot. Timothy was used as reference plant. The plants were placed at 15 ºC for twelve weeks and subjected to 18 or 24 h daylight. The 15N isotope dilution method was used to assess N2 -fixation. Results suggest that 24 h daylight increased white clover biomass production as compared to 18 h daylight and favoured leaf and stolon production significantly more at 85% of SDC than at 60% of SDC. However, for white clover plants grown at 18 h day length higher compactness reduced the root development. On average, white clover derived 44-58% of its total N from N2 -fixation grown at 60% of SDC and 46-47% at 85% of SDC, regardless of light conditions. The N2 -fixation was somewhat higher at 24 h day length only under the low soil compaction level.