| 1. |
- Arvidsson Segerkvist, Katarina, et al.
(författare)
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Effects of conservation method on fatty acid composition of silage
- 2009
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Ingår i: Animal Feed Science and Technology. - : Elsevier BV. - 0377-8401 .- 1873-2216. ; 148, s. 241-252
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Tidskriftsartikel (refereegranskat)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.
(författare)
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Fatty acids in forages: A comparison of different pre-treatments prior to analysis
- 2009
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Ingår i: Animal Feed Science and Technology. - : Elsevier BV. - 0377-8401 .- 1873-2216. ; 151, s. 143-152
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Tidskriftsartikel (refereegranskat)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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| 3. |
- Arvidsson Segerkvist, Katarina, et al.
(författare)
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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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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 6, s. 1178-1186
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Tidskriftsartikel (refereegranskat)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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| 4. |
- Bernes, Gun, et al.
(författare)
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Baljväxtensilage till får
- 2010
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Ingår i: Nytt från Institutionen för norrländsk jordbruksvetenskap. Ekologisk odling. - 1401-7741.
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Annan publikation (populärvet., debatt m.m.)
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| 5. |
- Bernes, Gun, et al.
(författare)
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Baljväxtensilage till får
- 2011
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Ingår i: Fårskötsel. - 1650-2426. ; , s. 20-23
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 6. |
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| 7. |
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| 9. |
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| 10. |
- Karlsson, Linda, et al.
(författare)
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Dietary influence on the m. longissimus dorsi fatty acid composition of lambs in relation to protein source
- 2012
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Ingår i: Meat Science. - : Elsevier BV. - 0309-1740 .- 1873-4138. ; 91, s. 472-477
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Tidskriftsartikel (refereegranskat)abstract
- Dietary lipid effect, as a consequence of protein supplement, on lamb m. longissimus dorsi fatty acid composition was investigated, with emphasis on biohydrogenation intermediates. Crossbred lambs (White Swedish Landrace x Texel) were fed a barley-based diet without (CON) or with protein supplements including peas (PEA), rapeseed cake (RC) or hempseed cake (HC). The HC diet resulted in the highest muscle 22:6n-3 proportion, with the RC diet being similar (P < 0.05). Protein supplement did not affect the c9,t11 conjugated linoleic acid (CLA) proportion, however the HC diet increased some minor CIA isomers, including t10,c12 CIA (P < 0.05). The t10-18:1 and total trans-18:1 were lowest for the RC diet (P < 0.05). likely relating to rumen conditions and precursor availability. The saturated, monounsaturated and branched-chain fatty acids were largely unaffected by protein supplement. In conclusion, feeding the RC diet lowered the t10-18:1 and total trans-18:1 in meat, and modestly increased 22:6n-3 content. The direction of these changes would be beneficial, making the RC diet the preferred protein supplement; however the magnitude of the changes in the present experiment may not be sufficient to have an impact on human health. (C) 2012 Elsevier Ltd. All rights reserved.
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