Sainfoin(Onobrychis viciifolia)silage in dairy cow rations reduces ruminal biohydrogenation and increases transfer efficiencies of unsaturated fatty acids from feed to milk

• 来源期刊: 动物营养（英文版）
• 年，卷（期）: 2020,（3）
• 所属期刊栏目: RUMINANT AND HERBIVORE NUTRITION
• 页码范围: 333-341
• 页数: 9页
• 语种: 英文

摘要

The effects of replacing grass silage by sainfoin silage in a total mixed ration(TMR)based diet on fatty acid(FA)reticular inflow and milk FA profile of dairy cows was investigated.The experiment followed a crossover design with 2 dietary treatments.The control diet consisted of grass silage,corn silage,concentrate and linseed.In the sainfoin diet,half of the grass silage was replaced by a sainfoin silage.Six rumen cannulated lactating multiparous dairy cows with a metabolic body weight of 132.5 ± 3.6 kg BW0.75,214 ± 72 d in milk and an average milk production of 23.1 ± 2.8 kg/d were used in the exper-iment Cows were paired based on parity and milk production.Within pairs,cows were randomly assigned to either the control diet or the sainfoin diet for 2 experimental periods(29 d per period).In each period,the first 21 d,cows were housed individually in tie-stalls for adaptation,then next 4 d cows were housed individually in climate-controlled respiration chambers to measure CH4.During the last 4 d,cows were housed individually in tie stalls to measure milk FA profile and determine FA reticular inflow using the reticular sampling technique with Cr-ethylenediaminetetraacetic acid disodium salt dihydrate(EDTA)and Yb-acetate used as digesta flow markers.Although the dietary C18:3n-3 intake was lower(P = 0.025)in the sainfoin diet group,the mono-unsaturated FA reticular inflow was greater(P = 0.042)in cows fed the sainfoin diet The reticular inflow of trans-9,trans-12-C18:2 and cis-12,trans-10 C18:2 was greater(P ≤ 0.024)in the sainfoin diet group.The cows fed sainfoin diet had a lower(P ≤ 0.038)apparent ruminal biohydrogenation of cis-9-C18:1 and C18:3n-3,compared to the cows fed the control diet The sainfoin diet group had greater(P ≤ 0.018)C18:3n-3 and cis-9,cis-12-C18:2 proportions in the milk FA profile compared to the control diet group.Transfer efficiencies from feed to milk of C18:2,C18:3n-3 and unsaturated FA were greater(P ≤ 0.0179)for the sainfoin diet Based on the results,it could be concluded that replacing grass silage by sainfoin silage in dairy cow rations reduces ruminal C18:3n-3 biohydrogenation and improves milk FA profile.