| 1. |
- Arvidsson Segerkvist, Katarina, et al.
(author)
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Effects of conservation method on fatty acid composition of silage
- 2009
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In: Animal Feed Science and Technology. - : Elsevier BV. - 0377-8401 .- 1873-2216. ; 148, s. 241-252
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Journal article (peer-reviewed)abstract
- This experiment was conducted to investigate effects of willing and additives on the fatty acid (FA) composition of grass silage. The crop used was timothy (Phelum pratense L., cv. Grindstad), and the additives were Proens (TM) (formic acid and propionic acid, 60-66 g/100 g and 25-30 g/100 g, respectively), the bacterial inoculant Silofenn (R) Plus (Pediococcus acidilactici and Lactobacillus plantarum) and water (control). The wilted material reached a dry matter (DM) content of 336 g/kg at the first cut and 350 g/kg at the second cut. Neither wilting nor the additives had any major effect on the FA proportions, with the only differences in the concentrations of C16:0 and C 18:3. Silage treated with bacterial inoculant contained a higher proportion of C16:0 (P<0.05) than silage treated with acid, and a lower (P<0.05) concentration of C 18:3 than silage treated with either of the other two additives. In the silages, there were lower (P<0.05) proportions of C:16:0, C 18:0, C 18:1 and C 18:3, and higher (.P<0.05) proportions of C 16: 1, C 19:2 and other identified FAs, than in the fresh material. A wilting process shorter than 24 h. to it DM content of 330-350 g/kg, did not have my effect on the proportions of FAs in P. pratense L., cv. Grindstad. Since the different additives and wilting strategies tested in this study did not affect the proportions of FAs in silage to a major extent, the results indicate that such it process offers a robust means to avoid losses of FAs that can occur during wilting, while retaining the positive effects of wilting, such its reduced losses of nutrients through effluents. (C) 2008 Elsevier B.V. All rights reserved.
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| 2. |
- Arvidsson Segerkvist, Katarina, et al.
(author)
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Fatty acid concentrations in timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.): Effects of seasonal variations at different nitrogen fertilization levels
- 2013
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In: Acta Agriculturae Scandinavica, Section B - Soil and Plant Science. - : Informa UK Limited. - 0906-4710 .- 1651-1913. ; 63, s. 314-321
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Journal article (peer-reviewed)abstract
- Timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.) were subjected to three different nitrogen (N) fertilization regimes (30+30, 90+90, and 120+90 kg N ha(1); N-30, N-90, and N-120 treatments, respectively) and harvested at three different stages of maturity during spring growth and at two different maturity stages during summer growth. In addition, N-90 plots were sampled on one additional occasion during spring growth and two additional occasions during summer growth. Total fatty acid concentrations and concentrations of the four major fatty acids (C16:0, C18:1n-9, C18:2n-6, and C18:3n-3), which account for 9094 g 100 g(1) of the total fatty acid contents of both grasses, declined over time during both growth periods in both grass species (p < 0.001), irrespective of N-fertilization level. Moreover, the relative proportions of the four fatty acids were affected by the harvest date (p < 0.001); C16:0, C18:1n-9, and C18:2n-6 increased in abundance at later harvest dates, while the opposite was true for C18:3n-3. There were differences (p < 0.05) between timothy and meadow fescue in terms of the concentrations of C16:0, C18:1n-9, C18:2n-6, and C18:3n-3, and in the relative proportions (p < 0.001) of C16:0, C18:2n-6, and C18:3n-3. Meadow fescue contained higher concentrations of C16:0, C18:1n-9, and C18:3n-3, while timothy contained higher concentrations of C18:2n-6. However, the total fatty acid concentrations for both species were similar. The N-fertilization level did not directly affect (p > 0.05) the concentrations or relative proportions of the different fatty acids, but positive linear relationships (p < 0.001) were identified between the concentrations of fatty acids and crude protein. Consequently, there is a scope for adjusting the fatty acid profile and content of forage by changing the grass species used and the time of harvest, with the latter having the greatest influence.
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| 3. |
- Arvidsson Segerkvist, Katarina, et al.
(author)
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Fatty acids in forages: A comparison of different pre-treatments prior to analysis
- 2009
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In: Animal Feed Science and Technology. - : Elsevier BV. - 0377-8401 .- 1873-2216. ; 151, s. 143-152
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Journal article (peer-reviewed)abstract
- The objective of this study was to compare the merits of various possible pre-treatments of samples of grass prior to fatty acid (FA) analysis. Initially, samples of both first and second cuts of a timothy ley (Phleum pratense L., cv. Grindstad) were subjected to ten different pre-treatments, including freezing with liquid N, freezing at -20°C and drying in an air-forced oven, then storage for eight to nine months. Their fatty acid contents were then determined, as fatty acid methyl esters, by gas chromatography. There were no distinct between-treatment differences in the determinations of total FA concentrations for either cut. However, there were treatment differences in the measured proportions of C16:0 and C18:0 (P < 0.01) for both cuts. There were also a few small differences (P < 0.05) in the proportions of C18:3 found in samples from both cuts, but not in their proportions of either C18:1 or C18:2. In subsequent experiments, samples from the first cut frozen at -20°C or dried in an air-forced oven were subjected to further treatments to investigate the effects of grinding and freeze-drying.. Samples of a second cut of red clover (Trifolium pratense L., cv. Betty) were also included in these experiments. There were no major between-preparation differences in the acquired data on FA composition for either the grass or clover samples. Notably, grinding had no significant effects on either the FA proportions or crude fat concentrations in the grass samples, although slightly higher (P < 0.01) proportions of C18:2 were found in the clover samples, and freeze-drying affected the FA proportions to some extent. In grass, freeze-drying resulted in lower (P < 0.05) concentrations of C18:0 and C18:1 compared to freezing alone (-20°C). If samples have to be stored for prolonged periods (such as the eight to nine months in this study) before analysis, drying seems to be a better treatment than freezing at -20°C. Freezing with liquid N was not essential, at least for the examined forages, to obtain apparently reliable information on their FA profiles. Thus, the widely used method of preparing samples prior to analysis, i.e. freeze drying and grinding, appears to be satisfactory, but drying samples seems to be as good or even better in some cases for analysing FA proportions.
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| 4. |
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| 5. |
- Arvidsson Segerkvist, Katarina, et al.
(author)
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Ger kvävegödsling eller inblandning av rödklöver i vallen någon effekt på mjölkens fettsyrasammansättning?
- 2014
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In: Report from the Department of Crop Production Ecology (VPE). - 1653-5375. ; , s. 117-119
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Book chapter (other academic/artistic)abstract
- Ett positivt samband mellan koncentrationen av råprotein och fettsyror har påvisats i en rad olika arter. Syftet med denna studie var att undersöka om detta samband kunde användas för att påverka mjölkens fettsyrasammansättning. Följaktligen gödslades en timotejvall med tre olika nivåer av kväve: 30, 90 och 120 kg N/ha till förstaskörd för att åstadkomma tre ensilage med olika råproteinkoncentration. Ett fjärde ensilage bestående av rödklöver och timotej (60 respektive 40 % på ts-basis) inkluderades också. Studien genomfördes under typiska produktionsbetingelser, dvs. med samma typer och mängder av kraftfoder som på en kommersiell gård. De uppnådda skillnaderna i fettsyrakoncentrationer mellan ensilagen påverkade dock inte mjölken, vilket visar att ökad kvävegödsling, eller inbladning av rödklöver, inte nödvändigtvis leder till högre koncentrationer av fleromättade fettsyror i mjölk vid en foderstat bestående av 60% vallfoder och 40% kraftfoder.
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| 6. |
- Arvidsson Segerkvist, Katarina, et al.
(author)
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The effect of N-fertilisation rate or inclusion of red clover to timothy leys on fatty acid composition in milk of dairy cows fed a commercial silage: concentrate ratio
- 2012
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In: Animal. - 1751-7311 .- 1751-732X. ; 6, s. 1178-1186
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Journal article (peer-reviewed)abstract
- The aim of this experiment was to, under typical Swedish production conditions, evaluate the effects of grass silages subjected to different N-fertilisation regimes fed to dairy cows on the fatty acid (FA) composition of their milk, and to compare the grass silages in this respect to red clover-dominated silage. Grass silages made from first year Phleum pratense L. leys subjected to three N-fertilisation regimes (30, 90 and 120 kg N/ha, designated G-30, G-90 and G-120, respectively) and a mixed red clover grass silage (Trifolium pratense L. and P. pratense L; 60/40 on dry matter (DM) basis, designated RC G) were produced. The experiment was conducted as a change-over design, including 24 primiparous and multiparous dairy cows of the Swedish Red breed, each of which was allocated to three of the four diets. The cows were offered 11 kg DM of silage and 7 kg concentrates. The silages had similar DM and energy concentrations. The CP concentration increased with increase in N-fertilisation level. There was a linear increase in DM intake of the different silages with increased N fertilisation. There were also differences in concentrations of both individual and total FAs amongst silages. The daily milk production (kg/day) did not significantly differ between treatments, but G-30 silage resulted in higher concentrations of 18:2n-6 in the milk compared with the other two grass silages. The highest concentrations of 18:3n-3 and cis-9, trans-11 18:2 were found in milk from cows offered the RC G silage. The G-30 diet resulted in higher concentration of 18:2n-6 and the same concentration of 18:3n-3 in the milk as the other grass silages, despite lower intake levels of these FAs. The apparent recoveries of 18:3n-3 from feed to milk were 5.74%, 4.27%, 4.10% and 5.31% for G-30, G-90, G-120 and RC G, respectively. A higher recovery when red clover is included in the diet confirms previous reports. The higher apparent recovery of 18:3n-3 on the G-30 treatment may be related to the lower silage DM intake, which led to a higher relative proportion of ingested FAs originating from concentrates compared with the G-90 and G-120 diets. With the rates and types of concentrates used in this study, the achieved differences in FA composition among the silages were not enough to influence the concentrations of unsaturated FAs in milk.
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| 7. |
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| 8. |
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| 9. |
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| 10. |
- Bernes, Gun, et al.
(author)
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Phytoestrogen concentration in red clover (Trifolium pratense L.) varieties
- 2016
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In: Grassland Science in Europe. ; 21, s. 254-256
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Conference paper (peer-reviewed)abstract
- Phytoestrogens (PE) are hormone-like plant substances that, when fed, may cause fertility problems, especially noticed in sheep. The aim of the study was to evaluate differences in PE concentration in red clover varieties. Two experiments were performed; Exp 1 with regrowth of 8 red clover varieties harvested at budding and at flowering and Exp 2 with regrowth of 12 varieties harvested at early flowering. There were significant differences between varieties for most PE. In Exp 1, when harvested on the same dates, Peggy, Ilte and SW Torun had higher mean concentration of formononetin, a potent PE, compared to SWA RK95097. When considering differences in maturity, Peggy, Ilte and LO RK9735 seemed to have a higher content than e.g. SW Ares. In Exp 2, Fregata had high concentration of total PE but the lowest content of formononetin. SW Betty and Ilte had high concentrations of both formononetin and coumestrol. Later harvest (Exp 1) gave decreased concentrations of most of the observed PE. The significant content of coumestrol that was found has not been previously reported for red clover.
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| 11. |
- Bernes, Gun, et al.
(author)
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Vårrybs - en intressant gröda i norr
- 2016
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In: Nytt / Sveriges lantbruksuniversitet, Institutionen för norrländsk jordbruksvetenskap.
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Other publication (pop. science, debate, etc.)
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| 12. |
- Frankow-Lindberg, Bodil, et al.
(author)
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Ecosystem function enhanced by combining four functional types of plant species in intensively managed grassland mixtures: a 3-year continental-scale field experiment
- 2013
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In: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 50, s. 365-375
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Journal article (peer-reviewed)abstract
- A coordinated continental-scale field experiment across 31 sites was used to compare the biomass yield of monocultures and four species mixtures associated with intensively managed agricultural grassland systems. To increase complementarity in resource use, each of the four species in the experimental design represented a distinct functional type derived from two levels of each of two functional traits, nitrogen acquisition (N2-fixing legume or nonfixing grass) crossed with temporal development (fast-establishing or temporally persistent). Relative abundances of the four functional types in mixtures were systematically varied at sowing to vary the evenness of the same four species in mixture communities at each site and sown at two levels of seed density. Across multiple years, the total yield (including weed biomass) of the mixtures exceeded that of the average monoculture in >97% of comparisons. It also exceeded that of the best monoculture (transgressive overyielding) in about 60% of sites, with a mean yield ratio of mixture to best-performing monoculture of 1 center dot 07 across all sites. Analyses based on yield of sown species only (excluding weed biomass) demonstrated considerably greater transgressive overyielding (significant at about 70% of sites, ratio of mixture to best-performing monoculture=1 center dot 18). Mixtures maintained a resistance to weed invasion over at least 3years. In mixtures, median values indicate <4% of weed biomass in total yield, whereas the median percentage of weeds in monocultures increased from 15% in year 1 to 32% in year 3. Within each year, there was a highly significant relationship (P<0 center dot 0001) between sward evenness and the diversity effect (excess of mixture performance over that predicted from the monoculture performances of component species). At lower evenness values, increases in community evenness resulted in an increased diversity effect, but the diversity effect was not significantly different from the maximum diversity effect across a wide range of higher evenness values. The latter indicates the robustness of the diversity effect to changes in species' relative abundances. Across sites with three complete years of data (24 of the 31 sites), the effect of interactions between the fast-establishing and temporal persistent trait levels of temporal development was highly significant and comparable in magnitude to effects of interactions between N2-fixing and nonfixing trait levels of nitrogen acquisition. Synthesis and applications. The design of grassland mixtures is relevant to farm-level strategies to achieve sustainable intensification. Experimental evidence indicated significant yield benefits of four species agronomic mixtures which yielded more than the highest-yielding monoculture at most sites. The results are relevant for agricultural practice and show how grassland mixtures can be designed to improve resource complementarity, increase yields and reduce weed invasion. The yield benefits were robust to considerable changes in the relative proportions of the four species, which is extremely useful for practical management of grassland swards.
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| 13. |
- Frankow-Lindberg, Bodil, et al.
(author)
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Major shifts in species' relative abundance in grassland mixtures alongside positive effects of species diversity in yield: a continental-scale experiment
- 2017
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In: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 105, s. 1210-1222
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Journal article (peer-reviewed)abstract
- 1. Increased species diversity promotes ecosystem function; however, the dynamics of multi-species grassland systems over time and their role in sustaining higher yields generated by increased diversity are still poorly understood. We investigated the development of species' relative abundances in grassland mixtures over 3 years to identify drivers of diversity change and their links to yield diversity effects.2. A continental-scale field experiment was conducted at 31 sites using 11 different four-species mixtures each sown at two seed abundances. The four species consisted of two grasses and two legumes, of which one was fast establishing and the other temporally persistent. We modelled the dynamics of the four-species mixtures, and tested associations with diversity effects on yield.3. We found that species' dynamics were primarily driven by differences in the relative growth rates (RGRs) of competing species, and secondarily by density dependence and climate. The temporally persistent grass species typically had the highest RGRs and hence became dominant over time. Density dependence sometimes induced stabilising processes on the dominant species and inhibited shifts to monoculture. Legumes persisted at most sites at low or medium abundances and persistence was improved at sites with higher annual minimum temperature.4. Significant diversity effects were present at the majority of sites in all years and the strength of diversity effects was improved with higher legume abundance in the previous year. Observed diversity effects, when legumes had declined, may be due to (i) important effects of legumes even at low abundance, (ii) interaction between the two grass species or (iii) a store of N because of previous presence of legumes.5. Synthesis. Alongside major compositional changes driven by RGR differences, diversity effects were observed at most sites, albeit at reduced strength as legumes declined. This evidence strongly supports the sowing of multi-species mixtures that include legumes over the long-standing practice of sowing grass monocultures. Careful and strategic selection of the identity of the species used in mixtures is suggested to facilitate the maintenance of species diversity and especially persistence of legumes over time, and to preserve the strength of yield increases associated with diversity.
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| 14. |
- Frankow-Lindberg, Bodil, et al.
(author)
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The agrodiversity experiment : three years of data from a multisite study in intensively managed grasslands
- 2014
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In: Ecology. - : Wiley. - 0012-9658 .- 1939-9170. ; 95, s. 2680-
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Other publication (peer-reviewed)abstract
- Intensively managed grasslands are globally prominent ecosystems. We investigated whether experimental increases in plant diversity in intensively managed grassland communities can increase their resource use efficiency. This work consisted of a coordinated, continental-scale 33-site experiment. The core design was 30 plots, representing 15 grassland communities at two seeding densities. The 15 communities comprised four monocultures (two grasses and two legumes) and 11 four-species mixtures that varied in the relative abundance of the four species at sowing. There were 1028 plots in the core experiment, with another 572 plots sown for additional treatments. Sites followed a protocol and employed the same experimental methods with certain plot management factors, such as seeding rates and number of cuts, determined by local practice. The four species used at a site depended on geographical location, but the species were chosen according to four functional traits: a fast-establishing grass, a slow-establishing persistent grass, a fast-establishing legume, and a slow-establishing persistent legume. As the objective was to maximize yield for intensive grassland production, the species chosen were all highyielding agronomic species. The data set contains species-specific biomass measurements (yield per species and of weeds) for all harvests for up to four years at 33 sites. Samples of harvested vegetation were also analyzed for forage quality at 26 sites. These data should be of interest to ecologists studying relationships between diversity and ecosystem function and to agronomists interested in sustainable intensification. The large spatial scale of the sites provides opportunity for analyses across spatial (and temporal) scales. The database can also complement existing databases and meta-analyses on biodiversity– ecosystem function relationships in natural communities by focusing on those same relationships within intensively managed agricultural grasslands.
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| 15. |
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| 16. |
- Gustavsson, Anne-Maj
(author)
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A developmental scale for perennial forage grasses based on the decimal code framework
- 2011
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In: Grass and Forage Science. - : Wiley. - 0142-5242 .- 1365-2494. ; 66, s. 93-108
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Journal article (peer-reviewed)abstract
- Accurate descriptions of developmental stages in perennial forage grasses are important for management decisions during the growing season. It would be advantageous to have a scale and index equivalent to those for other grasses such as cereals. Similar scales would simplify the activities of people working with several crops and facilitate comparisons between perennial forage grasses and related crops (e.g. whole-crop cereals). The objective of this paper is to develop a ‘forage grass decimal scale’, by adapting the universal decimal code framework already understood and used by many agricultural personnel. Furthermore, to improve harvest timing for high-quality silage, new definitions, based on stem development, are used to improve upon the morphological precision of the universal code for the pre- and post-booting periods. The code is adapted to describe individual tillers, while approaches to describe whole stands of forage grasses are also evaluated
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| 17. |
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| 18. |
- Gustavsson, Anne-Maj
(author)
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Benefits of mixing grasses and legumes for herbage yield and nutritive value in Northern Europe and Canada
- 2014
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In: Grass and Forage Science. - : Wiley. - 0142-5242 .- 1365-2494. ; 69, s. 229-240
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Journal article (peer-reviewed)abstract
- Increased biodiversity may improve ecosystem services, including herbage yield. A mixture experiment was carried out at five sites in Northern Europe and one in Canada to investigate whether mixtures of grasses and legumes would give higher herbage yield than monocultures. Resistance of the mixtures to weed invasion and nutritive value of the herbage were also investigated. The experimental layout followed a simplex design, where four species differing in specific functional traits, timothy (Phleum pratense L.), smooth meadow grass (Poa pratensis L.), red clover (Trifolium pratense L.) and white clover (Trifolium repens L.), were grown in monocultures and eleven different mixtures with systematically varying proportions of the four species. Positive diversity effects (DE) were observed, leading to greater herbage dry-matter (DM) yield in mixtures than expected from species sown in monocultures. For centroid mixtures, the DE generated on average an additional 32, 25 and 21% of the DM yield than would be expected from the monocultures in the first, second and third year respectively. On average, the mixtures were 9, 15 and 7% more productive than the most productive monoculture (transgressive overyielding) in the first, second and third year respectively. These benefits persisted over the three harvest years of the experiment and were consistent among most sites. This positive effect was not accompanied by a reduction in herbage digestibility and crude protein concentration that is usually observed with increased DM yield. Mixtures also reduced the invasion of weeds to <5% of herbage yield compared to monocultures (10-60% of herbage yield).
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| 19. |
- Gustavsson, Anne-Maj, et al.
(author)
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Concentrations of micro-nutrients in forage legumes and grasses harvested at different sites
- 2015
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In: Grassland Science in Europe. ; 20, s. 425-427
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Conference paper (peer-reviewed)abstract
- Forage is a major source of micronutrients for dairy cows. This study examined the concentrations of micronutrients in birdsfoot trefoil (Bf ), red clover (Rc), timothy (Ti) and meadow fescue (Mf ) at different sites, years and cutting dates. Mixtures of Bf+Ti, Rc+Ti and Rc+Mf were established at Skara (58°21'N; 13°08'E) and Umeå (63°45'N; 20°17'E) in Sweden. First-year leys (Umeå 2005, Skara 2005 and 2007) were cut on three occasions in spring relative to the maturity stage of timothy: one week before heading, at heading and one week after heading. Summer growth was cut six weeks after each of the three occasions in spring growth. The results show that there was a need for Cu supplementation in all treatments because of low Cu concentration. The relatively high Mo concentrations compared to the Cu concentration in both grasses at Skara, in Mf in second cut at Umeå, and in Bt in the second cut at Skara may further increase the demand for Cu supplementation in dairy cow rations because there is a risk that Cu can be bound to a sulphate-Mo-complex in the rumen. The Zn concentration was lower than required for dairy cows, except for the mixture with Ti and Rc in the second cut at Umeå. For Mn and Fe, concentration levels were appropriate for expected dairy cow requirements for all treatments.
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| 20. |
- Gustavsson, Anne-Maj
(author)
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Effect of silage botanical composition on ruminal biohydrogenation and transfer of fatty acids to milk in dairy cows
- 2013
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In: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 96, s. 1135-1147
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Journal article (peer-reviewed)abstract
- Ruminal biohydrogenation and transfer of fatty acids (FA) to milk were determined for 4 silages with different botanical compositions using 4 multiparous Norwegian Red dairy cows [(mean +/- SD) 118 +/- 40.9 d in milk, 22.5 +/- 2.72 kg of milk/d, 631 +/- 3.3 kg of body weight, 3.3 +/- 0.40 points on body condition score at the start of the experiment] fitted with rumen cannulas. Treatments consisted of 4 experimental silages: a mix of the first and third cut of organically managed short-term grass-land with timothy (Phleum pratense L.) and red clover (Trifolium pratense L.; 2 yr old; ORG-SG); organically managed long-term grassland with a high proportion of unsown species (6 yr old; ORG-LG); conventionally managed ley with perennial ryegrass (Lolium perenne L.; CON-PR); and conventionally managed ley with timothy (CON-TI). The herbages were cut, wilted, and preserved with additive in round bales and fed at 0.90 of ad libitum intake. A barley (Hordeum vulgare L.) concentrate constituted 300 g/kg of dry matter of the total feed offered. A Latin square design (4 x 4) with 3-wk periods and the last week in each period used for sampling was implemented. Omasal flows of FA were measured using Yb acetate, Cr-EDTA, and the indigestible neutral detergent fiber fraction as indigestible markers. The composition of FA was analyzed in feed, omasal digesta, and milk. Compared with ORG-LG, ORG-SG had a higher herbage proportion of red clover (0.36 vs. 0.01) and lower proportions of timothy (0.42 vs. 0.18), smooth meadowgrass (Poa pratensis L.), meadow fescue (Festuca pratensis Huds.), white clover (Trifolium repens L.), dandelion (Taraxacum spp.), and creeping buttercup (Ranunculus repens L.). The silages were well preserved. The concentration of neutral detergent fiber was higher and the concentration of Kjeldahl-N was lower for CON-TI than for the othersilages. Silage type had no effect on dry matter intake, but milk yield was lower for CON-TI than for the other silages. Apparent biohydrogenation of C18:3n-3 was lower for ORG-SG (932 g/kg) than for ORG-LG (956 g/kg), CON-PR (959 g/kg), and CON-TI (958 g/kg). Compared with the grass-based silages, ORG-SG and ORG-LG resulted in higher omasal flows of C18:1 trans FA and higher milk fat proportions of C18:1 trans FA and C18:2 cis-9, trans-11. Apparent recovery of C18:3n-3 in milk was higher for ORG-SG (61 g/kg) than for ORG-LG (33 g/kg), CON-PR (34 g/kg), and CON-TI (38 g/kg), and milk fat proportion of C18:3n-3 was higher for ORG-SG than for CON-TI. Milk fat proportions of C16:0 were lower for ORG-SG and ORG-LG compared with those for CON-PR and CON-TI. It was concluded that high proportions of red clover and other dicotyledons in the silages affected ruminal biohydrogenation and increased milk fat proportions of beneficial FA.
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| 21. |
- Gustavsson, Anne-Maj, et al.
(author)
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Effects of morphological fractions on estimated milk yields in forage maize depending on growing site and plant maturity
- 2013
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In: Acta Agriculturae Scandinavica, Section A - Animal Science. - : Informa UK Limited. - 0906-4702 .- 1651-1972. ; 63, s. 131-142
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Journal article (peer-reviewed)abstract
- This study was undertaken to determine the effects of the morphological fractions of forage maize for milk production as predicted by the spread sheet model called MILK 2006. The plants were harvested at increasing maturities at three different sites in Sweden and separated into stems, leaves, kernels and cobs. Chemical and in vitro analyses of the plant fractions as specified in the MILK 2006 model for predicting estimated milk yields Milk Mg-1 dry matter (DM) and Milk ha(-1) were undertaken. Partial least squares regression analysis was used to evaluate the impact of the proportions and qualities of the fractions on Milk Mg-1 DM and Milk ha(-1). Estimated milk yields could not be predicted based on the proportions of the fractions and their nutritional values. The most important parameters for determining Milk ha(-1) was the DM yield, and for the estimated Milk Mg-1 were the concentrations of starch and the fibre digestibility of the whole crop.
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| 22. |
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| 23. |
- Gustavsson, Anne-Maj, et al.
(author)
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Evaluation of the LINGRA timothy model under Nordic conditions
- 2014
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In: Field Crops Research. - : Elsevier BV. - 0378-4290 .- 1872-6852. ; 161, s. 87-97
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Journal article (peer-reviewed)abstract
- Simulation models are frequently applied to determine the production potential of forage grasses under various scenarios, including climate change. Thorough calibrations and evaluations of forage grass models can help improve their applicability. This study evaluated the ability of the Light Interception and Utilization Simulator-GRAss (LINGRA) model to predict biomass yield of timothy (Phleum pratense L. cv. Grindstad) in the Nordic countries. Variety trial data for the first and second year after establishment were obtained for seven locations: Jokioinen, Finland (60 degrees 48 ' N; 23 degrees 29 ' E), Maaninka, Finland (63 degrees 09 ' N; 27 degrees 18 ' E), Korpa, Iceland (64 degrees 09 ' N; 21 degrees 45 ' W), Srheim, Norway (58 degrees 41 ' N; 5 degrees 39 ' E), Lillerud, Sweden (59 degrees 24' N; 13 degrees 16 ' E), Ostersund, Sweden (63 degrees 15 ' N; 14 degrees 34 ' E) and Ulna Sweden (63 degrees 49 ' N; 20 degrees 13 ' E) from 1992 to 2012. Two calibrations of the LINGRA model were carried out using Bayesian techniques. In the first of these (SRrheim calibration), data on biomass yield and underlying variables obtained from independent field trials at Srheim were used. In the second (Nordic calibration), biomass data from the other locations were used as well. The model was validated against the remaining set of biomass yields from all locations not included in the Nordic calibration. The observed total seasonal yield the first and second year after establishment was 913 and 991 g DM m(-2) respectively on average across the locations. The corresponding average simulated yield after the Srheim calibration was 1044 (root mean square error (RMSE) 258) and 1112 g DM m(-2) (RMSE 312), respectively. After the Nordic calibration, the simulated average total seasonal yield was 863 (RMSE 242) the first year and 927 g DM m(-2) (RMSE 271) the second year after establishment. The differences between the observed and simulated first cut yield followed the same patterns, whereas the prediction accuracy for second cut yield did not differ substantially between the calibration approaches..Using the parameter set from the Nordic region decreased the model predictability at Srheim compared with only using model parameters derived from this location. These results show that using biomass data from several locations, instead of only one specific location, in the calibration of the LINGRA model improved the overall prediction accuracy of first cut dry matter yield and total seasonal dry matter yield across an environmentally heterogeneous region. To further analyse the usefulness of including multi-site data in forage grass model calibrations, other forage grass models could be evaluated against the same dataset. (C) 2014 Elsevier B.V. All rights reserved.
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| 24. |
- Gustavsson, Anne-Maj
(author)
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Fatty acid composition, fat-soluble vitamin concentrations and oxidative stability in bovine milk produced on two pastures with different botanical composition
- 2013
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In: Livestock Science. - : Elsevier BV. - 1871-1413 .- 1878-0490. ; 154, s. 93-102
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Journal article (peer-reviewed)abstract
- Previous research has shown that grazing pastures compared to feeding preserved forages has large impact on milk fatty acid (FA) composition, but differences between grazing red clover (Trifolium pratense L) or white clover (Trifolium repens L) are small, whereas the herbage proportions of dicotyledon botanical families is positively correlated with the milk-fat proportions of total polyunsaturated FA when grazing pastures in the Alps. The objective of the present study was to investigate the influence of botanically different pastures on bovine milk composition and milk susceptibility to oxidation. Two groups of 8 multiparous Norwegian Red dairy cows [mean (standard deviation); 599 (45.1) kg body weight, 73 (15.0) d in milk, 29.9 (2.90) kg milk/d at experiment start] grazed either a short-term pasture (SP) or a long-term pasture (LP). Both pastures were organically managed, meaning that no artificial fertilizers or herbicides were applied. The SP was representative for pastures, which are frequently, i.e. at least every third year, renewed by soil tillage and seeding, whereas LP was representative for pastures, which are less frequently renewed. The SP contained mainly meadow fescue (Festuca pratensis Huds.), timothy (Phleum pratense L.) and red clover and LP contained smooth meadow grass (Poa pratensis L), white clover and a variety of unsown species. Sixteen cows were blocked according to milk yield, days in milk and sire, and randomly within block allocated to the 2 dietary treatments with a daily pasture allowance of 15-20 kg dry matter per cow, supplemented with 3.0 kg barley (Hordeum vulgare L) concentrate. Milk was sampled during the last week of 3 experimental periods and analysed for FA composition by gas chromatography, concentrations of fat-soluble vitamins by high performance liquid chromatography, and oxidative stability in a light-exposure experiment by measuring the formation of hydroperoxides and by front-face fluorescence spectroscopy. Pasture type had no effect on milk yield, milk gross composition, and only minor effects on milk FA composition. Milk from SP had higher concentration of a-tocopherol than LP. The formation of hydroperoxides in milk was lower for SP than LP after 24 h light
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| 25. |
- Gustavsson, Anne-Maj
(author)
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Gastrointestinal metabolism of phytoestrogens in lactating dairy cows fed silages with different botanical composition
- 2014
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In: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 97, s. 7735-7750
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Journal article (peer-reviewed)abstract
- Dietary phytoestrogens are metabolized or converted in the gastrointestinal tract of ruminants, only limited knowledge exists on the extent and location of this conversion in vivo. The objective of this study was to quantify the gastro-intestinal metabolism of phytoestrogens in lactating dairy cows fed silages with different botanical composition. Four lactating rumen cannulated Norwegian Red cattle were assigned to a 4 x 4 Latin square with 1 cow per treatment period of 3 wk. The 4 treatment silages were prepared from grass-lands with different botanical compositions: organically managed short-term timothy (Phleum pratense L.) and red clover (Trifolium pratense L.) ley (2 yr old: ORG-SG); organically managed long-term grassland with a high proportion of unsown species (6 yr old; ORG-LG); conventionally managed perennial ryegrass (Lolium perenne L.) ley (CON-PR); and conventionally managed timothy ley (CON-TI). The herbages were cut, wilted, and preserved with additive in round bales, fed as a mix of the first and third cut at 90% of ad libitum intake, and contributed to 70% of the total dry matter intake. Milk, feed, omasal digesta, urine, and feces were collected at the end of each period and analyzed for the concentrations of phytoestrogens by using a liquid chromatography tandem mass spectrometry technique. Concentration of total isoflavones was highest in ORG-SG and lowest in CON-TI silage, whereas the content of total lignans was highest in the grass silages. The isoflavones were extensively metabolized in the rumen on all diets, and the recovery of formononetin and daidzein in omasum, mainly as equol, averaged 0.11 mg/mg. The apparent intestinal metabolism was less severe as, on average, 0.29 mg/mg of the omasal flow was recovered in feces. The plant lignans were also strongly degraded in the rumen. However, the flow of lignans to omasum and excretion in feces were, on average, 7.2- and 5.2-fold higher, respectively, than the intake of the plant lignans matairesinol and secoisolariciresinol, known as precursors of mammalian lignans. Thus, excretion to milk could not be directly related to intake, implying that plant lignans other than matairesinol and secoisolariciresinol in forage are precursors for enterolactone production in the rumen and for its content in milk. Equol followed mainly the flow of large particles out of the rumen, whereas the mammalian lignans were distributed between phases proportional to dry matter flow. The main metabolism of phytoestrogens occurred in the rumen and the main route of excretion was through feces and urine, with only a small part being excreted in milk. The concentration of phytoestrogens in milk can be manipulated through intake but the intermediate transfer capacity to milk appears to be limited by saturation.
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| 26. |
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| 27. |
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| 28. |
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| 29. |
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| 30. |
- Gustavsson, Anne-Maj
(author)
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Key challenges and priorities for modelling European grasslands under climate change
- 2016
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In: Science of the Total Environment. - : Elsevier BV. - 0048-9697. ; 566-567, s. 851-864
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Research review (peer-reviewed)abstract
- Grassland-based ruminant production systems are integral to sustainable food production in Europe, converting plant materials indigestible to humans into nutritious food, while providing a range of environmental and cultural benefits. Climate change poses significant challenges for such systems, their productivity and the wider benefits they supply. In this context, grassland models have an important role in predicting and understanding the impacts of climate change on grassland systems, and assessing the efficacy of potential adaptation and mitigation strategies. In order to identify the key challenges for European grassland modelling under climate change, modellers and researchers from across Europe were consulted via workshop and questionnaire. Participants identified fifteen challenges and considered the current state of modelling and priorities for future research in relation to each. A review of literature was undertaken to corroborate and enrich the information provided during the horizon scanning activities. Challenges were in four categories relating to: 1) the direct and indirect effects of climate change on the sward 2) climate change effects on grassland systems outputs 3) mediation of climate change impacts by site, system and management and 4) cross-cutting methodological issues. While research priorities differed between challenges, an underlying theme was the need for accessible, shared inventories of models, approaches and data, as a resource for stakeholders and to stimulate new research. Developing grassland models to effectively support efforts to tackle climate change impacts, while increasing productivity and enhancing ecosystem services, will require engagement with stakeholders and policy-makers, as well as modellers and experimental researchers across many disciplines. The challenges and priorities identified are intended to be a resource 1) for grassland modellers and experimental researchers, to stimulate the development of new research directions and collaborative opportunities, and 2) for policy-makers involved in shaping the research agenda for European grassland modelling under climate change. (C) 2016 Elsevier B.V. All rights reserved.
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| 31. |
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| 32. |
- Gustavsson, Anne-Maj
(author)
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Modelling grass yields in northern climates - a comparison of three growth models for timothy
- 2018
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In: Field Crops Research. - : Elsevier BV. - 0378-4290 .- 1872-6852. ; 224, s. 37-47
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Journal article (peer-reviewed)abstract
- During the past few years, several studies have compared the performance of crop simulation models to assess the uncertainties in model-based climate change impact assessments and other modelling studies. Many of these studies have concentrated on cereal crops, while fewer model comparisons have been conducted for grasses. We compared the predictions for timothy grass (Phleum pratertse L.) yields for first and second cuts along with the dynamics of above-ground biomass for the grass simulation models BASGRA and CATIMO, and the soil -crop model STICS. The models were calibrated and evaluated using field data from seven sites across Northern Europe and Canada with different climates, soil conditions and management practices. Altogether the models were compared using data on timothy grass from 33 combinations of sites, cultivars and management regimes. Model performances with two calibration approaches, cultivar-specific and generic calibrations, were compared. All the models studied estimated the dynamics of above-ground biomass and the leaf area index satisfactorily, but tended to underestimate the first cut yield. Cultivar-specific calibration resulted in more accurate first cut yield predictions than the generic calibration achieving root mean square errors approximately one third lower for the cultivar-specific calibration. For the second cut, the difference between the calibration methods was small. The results indicate that detailed soil process descriptions improved the overall model performance and the model responses to management, such as nitrogen applications. The results also suggest that taking the genetic variability into account between cultivars of timothy grass also improves the yield estimates. Calibrations using both spring and summer growth data simultaneously revealed that processes determining the growth in these two periods require further attention in model development.
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| 33. |
- Gustavsson, Anne-Maj
(author)
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Phyto-oestrogens and their metabolites in milk produced on two pastures with different botanical compositions
- 2014
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In: Livestock Science. - : Elsevier BV. - 1871-1413 .- 1878-0490. ; 163, s. 62-68
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Journal article (peer-reviewed)abstract
- Phyto-oestrogens are a group of secondary plant metabolites that may bind to oestrogen receptors and exert oestrogenic or anti-oestrogenic effects in humans and can protect against cancer diseases. When ingested by dairy cows, phyto-oestrogens can be metabolised and transferred to the milk. The objective of this study was to assess the effects of grazing a recently established pasture containing red clover (Trifolium pratense L.) and an older pasture containing a variety of sown and unsown plant species on milk concentrations of phyto-oestrogens. Sixteen Norwegian Red dairy cows [mean (standard deviation); body weight 599 (45.1) kg, stage of lactation 73 (15.0) d in milk, milk yield 29.9 (2.90) kg/d at the start of the experiment] were divided into two groups and grazed either a short-term pasture (SP) or a long-term pasture (LP). The SP was representative of organically managed leys in Norway, which are frequently, approximately every third year, renewed by soil tillage and seeding, whereas LP was representative of organically managed grasslands that are less frequently renewed. The SP contained meadow fescue (Festuca pratensis Huds.) (mean 34%), timothy (Phleum pratense L) (mean 19%), red clover (mean 28%), shepherd's-purse (Capsella bursa-pastoris (L) Medik.) (mean 6%), pineappleweed (Matricaria matricarioides Porter ex Britton) (mean 5%) and scentless mayweed (Tripleurospermum perforatum (Merat) Lainz) (mean 4%), and LP contained mainly white clover (Trifolium repens L) (mean 21%), smooth meadowgrass (Poa pratensis L.) (mean 19%), timothy (mean 17%), meadow fescue (mean 15%), perennial ryegrass (Lolium perenne L) (mean 6%), tufted hairgrass (Deschampsia cespitosa (L) P. Beauv.) (mean 5%), northern dock (Rumex longifolius DC.) (mean 4%), common couch (Elytrigia repens (L) Desv. Ex Nevski) (mean 4%), red clover (mean 3%) and dandelion (Taraxacum spp.) (mean 3%). In addition to a daily pasture allowance of 20 kg dry matter per cow, supplements of 3.0 kg barley (Hordeum vulgare L.) concentrate were fed. Herbage, concentrates and milk was sampled during the last week of three experimental periods and analysed for phytooestrogens using LC-MS/MS technology. Herbage from SP had 19 times higher concentration of isoflavones than herbage from LP, whereas only small differences were found for lignans. Milk produced on SP had 14 times higher concentrations of the mammalian isoflavonoid equol, and the concentrations of equol were higher than found in most other studies. This study confirms that grazing pastures containing red clover increases concentrations of isoflavones and especially equol in bovine milk compared to grazing pastures with other botanical composition. The higher milk concentrations of the lignan metabolite enterodiol in milk from SP compared to LP could not be related to differences in intake of the analysed lignans and may therefore be related to unidentified lignans. (C) 2014 Elsevier B.V. All rights reserved.
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| 34. |
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| 35. |
- Gustavsson, Anne-Maj
(author)
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Simulation of timothy nutritive value: A comparison of three process-based models
- 2019
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In: Field Crops Research. - : Elsevier BV. - 0378-4290 .- 1872-6852. ; 231, s. 81-92
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Journal article (peer-reviewed)abstract
- Different forage grass models are used to simulate forage yield and nutritive attributes, but these models are seldom compared, particularly those for timothy (Phlewn pratense L.), a widely grown forage grass species in agricultural regions with a cold temperate climate. We compared the models BASGRA, CATIMO and STICS for their predictions of timothy crude protein (CP) concentration, neutral detergent fibre (NDF) concentration and NDF digestibility (dNDF), three important forage nutritive attributes. Data on CP and NDF concentrations, and dNDF and the associated weather and soil data for seven cultivars, taken from eight field experiments in Canada, Finland, Norway, and Sweden, were divided into calibration and validation datasets. Model parameters were estimated for each cultivar separately (cultivar-specific calibration) and for all cultivars together (generic calibration), using different methods for the three models. Normalized root mean square error (RMSE) in prediction of CP concentration varied between 16 and 26% for BASGRA, 45 and 101% for CATIMO and 23 and 40% for STICS across the two calibration methods and the calibration and validation datasets. Normalised RMSE in prediction of NDF concentration varied between 8 and 13% for BASGRA, 14 and 21% for CATIMO and 8 and 12% for STICS, while for dNDF it varied between 7 and 22% for BASGRA, 7 and 38% for CATIMO and 5 and 6% for STICS. Cultivar-specific calibration improved the performance of CATIMO and STICS, but not BASGRA, compared with generic calibration. The prediction accuracy for NDF concentration and dNDF with the three models was within the same range or better than that for forage dry matter (DM) yield of timothy. Overall, the three models performed well in predicting some nutritive attributes and yield in Northern Europe and Canada, but improvements are required, particularly to increase the prediction accuracy of CP concentration.
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| 36. |
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| 37. |
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| 38. |
- Gustavsson, Anne-Maj, et al.
(author)
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Vallar, beten och grönfoderväxter
- 2015
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In: Vår mat- odling av åker- och trädgårdsgrödor. - 9789144092805 ; , s. 353-386
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Book chapter (pop. science, debate, etc.)
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| 39. |
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| 40. |
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| 41. |
- Gustavsson, Anne-Maj
(author)
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Variation in rate of phenological development and morphology between red clover varieties: Implications for clover proportion and feed quality in mixed swards
- 2019
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In: Grass and Forage Science. - : Wiley. - 0142-5242 .- 1365-2494. ; 74, s. 403-414
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Journal article (peer-reviewed)abstract
- Red clover (Trifolium pratense) grown in mixtures with grasses often constitutes a lower proportion of total yield in spring than in summer growth. A more even red clover proportion between the harvests would benefit forage quality and management at feeding. We investigated whether inclusion of early versus late-maturing red clover varieties could reduce this disproportionality. In a two-year field trial harvested three times per season, each of six red clover varieties was grown in two grass mixtures. Rate of phenological development did not differ during spring growth, but did so in regrowth after first and second cuts. Here, the earliest varieties constituted the highest proportion. At all harvests, the early varieties had lower crude protein concentrations and a higher content of neutral detergent fibre (NDF) and indigestible NDF than the late varieties. Clover proportion was higher in swards with a mixture of timothy and meadow fescue than in swards with perennial ryegrass during the first year and lower in the second year. It is concluded that developmental rate should be explored further as a key character for red clover competiveness in spring growth of rapidly elongating grasses.
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| 42. |
- Gustavsson, Anne-Maj
(author)
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Weed suppression greatly increased by plant diversity in intensively managed grasslands: A continental-scale experiment
- 2018
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In: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 55, s. 852-862
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Journal article (peer-reviewed)abstract
- 1. Grassland diversity can support sustainable intensification of grassland production through increased yields, reduced inputs and limited weed invasion. We report the effects of diversity on weed suppression from 3 years of a 31-site continental-scale field experiment.2. At each site, 15 grassland communities comprising four monocultures and 11 four-species mixtures based on a wide range of species' proportions were sown at two densities and managed by cutting. Forage species were selected according to two crossed functional traits, "method of nitrogen acquisition" and "pattern of temporal development".3. Across sites, years and sown densities, annual weed biomass in mixtures and monocultures was 0.5 and 2.0 t DM ha(-1) (7% and 33% of total biomass respectively). Over 95% of mixtures had weed biomass lower than the average of monocultures, and in two-thirds of cases, lower than in the most suppressive monoculture (transgressive suppression). Suppression was significantly transgressive for 58% of site-years. Transgressive suppression by mixtures was maintained across years, independent of site productivity.4. Based on models, average weed biomass in mixture over the whole experiment was 52% less (95% confidence interval: 30%-75%) than in the most suppressive monoculture. Transgressive suppression of weed biomass was significant at each year across all mixtures and for each mixture.5. Weed biomass was consistently low across all mixtures and years and was in some cases significantly but not largely different from that in the equiproportional mixture. The average variability (standard deviation) of annual weed biomass within a site was much lower for mixtures (0.42) than for monocultures (1.77).6. Synthesis and applications. Weed invasion can be diminished through a combination of forage species selected for complementarity and persistence traits in systems designed to reduce reliance on fertiliser nitrogen. In this study, effects of diversity on weed suppression were consistently strong across mixtures varying widely in species' proportions and over time. The level of weed biomass did not vary greatly across mixtures varying widely in proportions of sown species. These diversity benefits in intensively managed grasslands are relevant for the sustainable intensification of -agriculture and, importantly, are achievable through practical farm-scale actions.
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| 43. |
- Hetta, Mårten, et al.
(author)
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Effects of hybrid and maturity on performance and nutritive characteristics of forage maize at high latitudes, estimated using the gas production technique
- 2012
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In: Animal Feed Science and Technology. - : Elsevier BV. - 0377-8401 .- 1873-2216. ; 171, s. 20-30
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Journal article (peer-reviewed)abstract
- We evaluated effects of hybrid and advancing plant maturity on performance, chemical composition, and nutritional characteristics of whole plant forage maize as well as the relative contributions of its plant fractions at high latitudes. Three maize hybrids, Avenir (FAO 180), Isberi (FAO 190) and Burli (FAO 210), were grown in southern Sweden in a field experiment with a replicated complete randomized block design. Plants were harvested four times during maturation, and dry matter (DM) yield and DM as a proportion of fresh weight were recorded. Whole plants were separated into four morphological fractions representing stems, leaves, kernels and cobs and the contribution of each fraction to the DM of the whole plant was estimated. Plant material was subjected to chemical analysis followed by measurement of in vitro gas production (GP) in buffered rumen fluid and finally, by calculation of in vitro true digestibility of organic matter (OM) and neutral detergent fibre (aNDFom). The GP profiles were fitted to a first order kinetic model with a discrete lag. Parameters describing the GP profiles were used in a recently developed mechanistic two compartment rumen degradation model to estimate in vivo OM digestibility (OMD) and first order rate of degradation in the rumen. Hybrids were compared and effects of maturity were assessed by analysis of variance using DM concentration as covariate. There were differences (P<0.05) among the hybrids in DM yield and relative contributions of the plant fractions. Differences (P<0.05) in modelled in vivo digestibility of OM and rates of degradation also occurred among hybrids. Increased maturity caused a reduction in in vitro digestibility of aNDFom in all plant fractions (P<0.05), but increased the rate of rumen degradation of OM in the whole plant as evaluated from GP results. The DM yield had a quadratic relationship with increasing maturity, with maximum yield at a DM concentration of about 370 g/kg. In vitro GP can describe the nutritive characteristics of forage maize in relation to advancing maturity and increased maturity affected agronomic performance and plant composition as well as the nutritive characteristics of hybrids. (C) 2011 Elsevier B.V. All rights reserved.
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| 44. |
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| 45. |
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| 46. |
- Höjer, Annika, et al.
(author)
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Effects of feeding dairy cows different legume-grass silages on milk phytoestrogen concentration
- 2012
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In: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 95, s. 4526-4540
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Journal article (peer-reviewed)abstract
- Phytoestrogens are hormone-like substances in plants that can substantially influence human health (positively or negatively), and when fed to dairy cows are partly transferred to their milk. The aim of this study was to investigate the effects of varying the botanical composition and regrowth interval of legume-grass silage on phytoestrogen intake and milk phytoestrogen concentrations. In one experiment, 15 Swedish Red dairy cows were fed 2- or 3-cut red clover-grass silage, or 2-cut birdsfoot trefoil-grass silage. In a second experiment, 16 Norwegian Red dairy cows were fed short-term ley silage with red clover or long-term ley silage with white clover, and the effects of supplementation with a-tocopherol were also tested. High concentrations of formononetin and biochanin A were found in all silage mixtures with red clover. The milk concentration of equol was highest for cows on the 2-cut red clover-grass silage diet (1,494 mu g/kg of milk). Because of the metabolism of biochanin A, genistein, and prunetin, their concentrations in milk and the apparent recovery were low. Coumestrol was detected in only short-term and long-term ley silage mixtures, and its milk concentration was low. Concentrations of secoisolariciresinol and matairesinol were higher in 2-cut birdsfoot trefoil-grass and long-term ley silage mixtures, those with legume species other than red clover, and the highest grass proportions. The 2-cut birdsfoot trefoil-grass silage diet also resulted in higher enterolactone concentration than the other diets (226 mu g/kg of milk). Lengthening the regrowth interval increased the intake of secoisolariciresinol and decreased the recovery of lignans. Feeding long-term ley silage resulted in higher milk lignan concentrations but lower milk isoflavone concentrations than feeding short-term ley silage. The apparent recovery of all phytoestrogens except prunetin was highest on the 2-cut birdsfoot trefoil-grass silage diet. No effect of alpha-tocopherol supplementation was observed on milk concentrations of any of the measured phytoestrogens. Variations were observed 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, but questions regarding phytoestrogen metabolism remain to be answered.
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| 47. |
- Höjer, Annika, et al.
(author)
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Fytoöstrogener i foder och mjölk
- 2013
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In: Nytt / Sveriges lantbruksuniversitet, Institutionen för norrländsk jordbruksvetenskap.
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Other publication (pop. science, debate, etc.)
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| 48. |
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| 49. |
- Höjer, Annika, et al.
(author)
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Fytoöstrogener – senaste nytt
- 2012
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In: Rapport / SLU, Institutionen för norrländsk jordbruksvetenskap. ; , s. 16-17
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Conference paper (other academic/artistic)
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| 50. |
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